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Sample records for head scatter factors

  1. Linac head scatter factor for asymmetric radiation field

    NASA Astrophysics Data System (ADS)

    Soubra, Mazen Ahmed

    1997-11-01

    The head scatter factor, Sh is an important dosimetric quantity used in radiation therapy dose calculation. It is empirically determined and its field size dependence reflects changes in photon scatter from components in the linac treatment head. In this work a detailed study of the physical factors influencing the determination of Sh was performed with particular attention given to asymmetric field geometries. Ionization measurements for 6 and 18 MV photon beams were made to examine the factors which determine Sh. These include: phantom size and material, collimator backscatter, non-lateral electronic equilibrium (LEE) conditions, electron contamination, collimator-exchange, photon energy, flattening filter and off-axis distance (OAD). Results indicated that LEE is not required for Sh measurements if electron contamination is minimized. Brass caps or polystyrene miniphantoms can both be used in Sh measurements provided the phantom thickness is large enough to stop contaminant electrons. Backscatter radiation effects into the monitor chamber were found to be negligible for the Siemens linac. It was found that the presence and shape of the flattening filter had a significant effect on the empirically determined value of Sh was also shown to be a function of OAD, particularly for small fields. For fields larger than 12×12 cm2/ Sh was independent of OAD. A flattening filter mass model was introduced to explain qualitatively the above results. A detailed Monte Carlo simulation of the Siemens KD2 linac head in 6 MV mode was performed to investigate the sources of head scatter which contribute to the measured Sh. The simulated head components include the flattening filter, the electron beam stopper, the primary collimator, the photon monitor chamber and the secondary collimators. The simulations showed that the scatter from the head of the Siemens linac is a complex function of the head components. On the central axis the flattening filter played the dominant role in

  2. Measurement and comparison of head scatter factor for 7 MV unflattened (FFF) and 6 MV flattened photon beam using indigenously designed columnar mini phantom

    PubMed Central

    Ashokkumar, Sigamani; Nambiraj, Arunai; Sinha, Sujit Nath; Yadav, Girigesh; Raman, Kothanda; Bhushan, Manindra; Thiyagarajan, Rajesh

    2015-01-01

    Aim To measure and compare the head scatter factor for 7 MV unflattened and 6 MV flattened photon beam using a home-made designed mini phantom. Background The head scatter factor (Sc) is one of the important parameters for MU calculation. There are multiple factors that influence the Sc values, like accelerator head, flattening filter, primary and secondary collimators. Materials and methods A columnar mini phantom was designed as recommended by AAPM Task Group 74 with high and low atomic number material for measurement of head scatter factors at 10 cm and dmax dose water equivalent thickness. Results The Sc values measured with high-Z are higher than the low-Z mini phantoms observed for both 6MV-FB and 7MV-UFB photon energies. Sc values of 7MV-UFB photon beams were smaller than those of the 6MV-FB photon beams (0.6–2.2% (Primus), 0.2–1.4% (Artiste) and 0.6–3.7% (Clinac iX (2300CD))) for field sizes ranging from 10 cm × 10 cm to 40 cm × 40 cm. The SSD had no influence on head scatter for both flattened and unflattened beams. The presence of wedge filters influences the Sc values. The collimator exchange effects showed that the opening of the upper jaw increases Sc irrespective of FF and FFF. Conclusions There were significant differences in Sc values measured for 6MV-FB and unflattened 7MV-UFB photon beams over the range of field sizes from 10 cm × 10 cm to 40 cm × 04 cm. Different results were obtained for measurements performed with low-Z and high-Z mini phantoms. PMID:25949220

  3. Comparison of Head Scatter Factor for 6MV and 10MV flattened (FB) and Unflattened (FFF) Photon Beam using indigenously Designed Columnar Mini Phantom

    PubMed Central

    Ashokkumar, Sigamani; Nambi Raj, N Arunai; Sinha, Sujit Nath; Yadav, Girigesh; Thiyagarajan, Rajesh; Raman, Kothanda; Mishra, Manindra Bhushan

    2014-01-01

    To measure and compare the head scatter factor for flattened (FB) and unflattened (FFF) of 6MV and 10MV photon beam using indigenously designed mini phantom. A columnar mini phantom was designed as recommended by AAPM Task Group 74 with low and high atomic number materials at 10 cm (mini phantom) and at approximately twice the depth of maximum dose water equivalent thickness (brass build-up cap). Scatter in the accelerator (Sc) values of 6MV-FFF photon beams are lesser than that of the 6MV-FB photon beams (0.66-2.8%; Clinac iX, 2300CD) and (0.47-1.74%; True beam) for field sizes ranging from 10 × 10 cm2 to 40 × 40 cm2. Sc values of 10MV-FFF photon beams are lesser (0.61-2.19%; True beam) than that of the 10MV-FB photons beams for field sizes ranging from 10 × 10 cm2 to 40 × 40 cm2. The SSD had no influence on head scatter for both flattened and unflattened beams and irrespective of head design of the different linear accelerators. The presence of field shaping device influences the Sc values. The collimator exchange effect reveals that the opening of the upper jaw increases Sc irrespective of FB or FFF photon beams and different linear accelerators, and it is less significant in FFF beams. Sc values of 6MV-FB square field were in good agreement with that of AAPM, TG-74 published data for Varian (Clinac iX, 2300CD) accelerator. Our results confirm that the removal of flattening filter decreases in the head scatter factor compared to flattened beam. This could reduce the out-of-field dose in advanced treatment delivery techniques. PMID:25190997

  4. Quantitative Analysis of the Head Scatter and Jaw Transmission Correction Factor for Commissioning of Enhanced Dynamic Wedge Fields Using a MapCHECK 2 Diode Array

    NASA Astrophysics Data System (ADS)

    Dickerson, Edward C.

    Quality assurance in radiation oncology treatment planning requires independent verification of dose to be delivered to a patient through "second check" calculations for simple plans as well as planar dose fluence measurements for more complex treatments, such as intensity modulated radiation treatments (IMRT). Discrepancies between treatment planning system (TPS) and second check calculations created a need for treatment plan verification using a two dimensional diode array for Enhanced Dynamic Wedge (EDW) fields. While these measurements met clinical standards for treatment, they revealed room for improvement in the EDW model. The purpose of this study is to analyze the head scatter and jaw transmission effects of the moving jaw in EDW fields by measuring dose profiles with a two dimensional diode array in order to minimize differences between the manufacturer provided fluence table (Golden Segmented Treatment Table) and actual machine output. The jaw transmission effect reduces the dose gradient in the wedge direction due to transmission photons adding dose to the heel region of the field. The head scatter effect also reduces the gradient in the dose profile due to decreased accelerator output at increasingly smaller field sizes caused by the moving jaw. The field size continuously decreases with jaw motion, and thus the toe region of the wedge receives less dose than anticipated due to less head scatter contribution for small field sizes. The Golden Segmented Treatment Table (GSTT) does not take these factors into account since they are specific to each individual machine. Thus, these factors need to be accounted for in the TPS to accurately model the gradient of the wedge. The TPS used in this clinic uses one correction factor (transmission factor) to account for both effects since both factors reduce the dose gradient of the wedge. Dose profile measurements were made for 5x5 cm2, 10x10 cm2, and 20x20 cm2 field sizes with open fields and 10°, 15°, 20°, 25

  5. Inelastic Scattering Form Factors

    Energy Science and Technology Software Center (ESTSC)

    1992-01-01

    ATHENA-IV computes form factors for inelastic scattering calculations, using single-particle wave functions that are eigenstates of motion in either a Woods-Saxon potential well or a harmonic oscillator well. Two-body forces of Gauss, Coulomb, Yukawa, and a sum of cut-off Yukawa radial dependences are available.

  6. An FDTD model of scattering from meteor head plasma

    NASA Astrophysics Data System (ADS)

    Marshall, R. A.; Close, S.

    2015-07-01

    We have developed a three-dimensional finite difference time domain (FDTD) model of scattering of radar waves from meteor head plasma. The model treats the meteor head plasma as a cold, collisional, and magnetized plasma, and solves Maxwell's equations and the Langevin equation simultaneously and self-consistently in and around the plasma. We use this model to investigate scattering of radar waves from a meteor head (the "head echo") under a range of plasma densities, meteor scale sizes, and wave frequencies. In this way we relate the radar cross section (RCS) to these variable parameters. We find that computed RCS disagrees with previous analytical theory at certain meteor sizes and densities, in some cases by over an order of magnitude. We find that the calculated meteor head RCS is monotonically related to the "overdense area" of the meteor, defined as the cross-section area of the part of the meteor where the plasma frequency exceeds the wave frequency. These results provides a physical measure of the meteor size and density that can be inferred from measured RCS values from ground-based radars. Meteoroid mass can then be inferred from the meteor plasma distribution using established methods.

  7. Analysing collimator structure effects in head-scatter calculations for IMRT class fields using scatter raytracing.

    PubMed

    Naqvi, S A; Sarfaraz, M; Holmes, T; Yu, C X; Li, X A

    2001-07-01

    The frequent blocking of the irradiated volume in intensity modulated radiation therapy (IMRT) makes the head-scatter fraction of the incident photon fluence more significant than that in conventional therapy with open fields. On the other hand. certain collimator configurations block scatter photons directed to a given observation point while allowing primary photons to be transmitted. The 'anomalous blocking' makes the primary field a poor indicator of the scatter fluence. Since large MU-to-cGy ratios in IMRT can magnify head-scatter uncertainties, it becomes necessary to accurately model both the effective scatter source and the collimator structure that limits the scatter reaching the irradiated volume. First we obtain a dual-source model, using a Taylor series expansion to derive the effective scatter source distribution from the data measured for the Elekta SL20 linac equipped with a multi-leaf collimator (MLC). Then, using a raytracing algorithm, we calculate the transmission of scatter rays from the effective scatter source plane to points in the patient plane. The method can account for the anomalous blocking of scatter by the MLC leaves and the backup diaphragms. For a variety of collimator settings tested, the calculations agree with measurements to an accuracy of 0.002psi10 x 10, where psi10 x 10 is the total (primary + scatter) photon fluence of an open 10 x 10 cm2 field for the same MU delivered. Although the significance of collimator structure in IMRT depends strongly on fields shapes employed for the delivery, potential cumulative errors on the order of a few per cent can be avoided in fluence calculations if the proposed method is used. PMID:11474941

  8. Scatter factor and reliability of aircraft structures

    NASA Technical Reports Server (NTRS)

    Schueller, G. I.; Freudenthal, A. M.

    1972-01-01

    The concept of time to first failure is utilized to perform a parameter study of scatter factors of aircraft structures. The Weibull distribution is used for estimation of characteristic and certifiable lives. Scatter factors for various Weibull-shaped parameters, fleet sizes and level of reliabilities are calculated. It is concluded that the currently used range of scatter factors (2 through 4) is too narrow for the estimation of a safe life and that a safe and economical design for structural materials with shape parameters less than 2 does not seem feasible except for very small fleet sizes and low levels of reliability.

  9. Finite source depolarization factors for circumstellar scattering

    NASA Technical Reports Server (NTRS)

    Brown, John C.; Carlaw, Vivette A.; Cassinelli, Joseph P.

    1989-01-01

    A single scattering theory is used to directly derive the D(r) result of Cassinelli et al (1987) and to investigate the extent to which it can be generalized to nonuniform spherical light sources, nonspherical light sources, arbitrary spatial distributions of scattering electrons, and scattering particles other than electrons. Expressions are also obtained for the factor by which the total scattered (as well as polarized) intensity is modified by finite size light sources, which is relevant to the case where the much stronger direct unpolarized starlight is eclipsed.

  10. Relativistic Thomson Scatter from Factor Calculation

    Energy Science and Technology Software Center (ESTSC)

    2009-11-01

    The purpose of this program is calculate the fully relativistic Thomson scatter from factor in unmagnetized plasmas. Such calculations are compared to experimental diagnoses of plasmas at such facilities as the Jupiter laser facility here a LLNL.

  11. Scatter factor induces blood vessel formation in vivo.

    PubMed Central

    Grant, D S; Kleinman, H K; Goldberg, I D; Bhargava, M M; Nickoloff, B J; Kinsella, J L; Polverini, P; Rosen, E M

    1993-01-01

    Scatter factor (also known as hepatocyte growth factor) is a glycoprotein secreted by stromal cells that stimulates cell motility and proliferation. In vitro, scatter factor stimulates vascular endothelial cell migration, proliferation, and organization into capillary-like tubes. Using two different in vivo assays, we showed that physiologic quantities of purified native mouse scatter factor and recombinant human hepatocyte growth factor induce angiogenesis (the formation of new blood vessels). The angiogenic activity was blocked by specific anti-scatter factor antibodies. Scatter factor induced cultured microvascular endothelial cells to accumulate and secrete significantly increased quantities of urokinase, an enzyme associated with development of an invasive endothelial phenotype during angiogenesis. We further showed that immunoreactive scatter factor is present surrounding sites of blood vessel formation in psoriatic skin. These findings suggest that scatter factor may act as a paracrine mediator in pathologic angiogenesis associated with human inflammatory disease. Images Fig. 1 Fig. 2 Fig. 3 Fig. 5 PMID:7680481

  12. Avoidable factors contributing to death of children with head injury.

    PubMed Central

    Sharples, P M; Storey, A; Aynsley-Green, A; Eyre, J A

    1990-01-01

    OBJECTIVE--To assess the incidence of potentially avoidable complications contributing to death of children with head injuries. DESIGN--Retrospective review of children who died with head injuries from 1979 to 1986 from data of the Office of Population Censuses and Surveys, Hospital Activity Analyses, case notes, coroners' records, and necropsy reports. SETTING--District general hospitals and two regional neurosurgical centres in Northern region. RESULTS--255 Children died from head injury in the region, the mortality being 5.3 per 100,000 children per year. Head injury was the single most important cause of death in children aged greater than 1 year, accounting for 15% of deaths in children aged 1-15 years and a quarter for those aged 5-15 years. 121 Potentially avoidable factors possibly or probably contributing to death occurred in 81 children (32%). Half the children (125) died before admission, 27 of whom (22%) had potentially avoidable factors possibly or probably contributing to death, and 130 died after admission, 54 of whom (42%) had 93 such factors, which included failure of diagnosis or delayed recognition of intracranial haemorrhage or associated injury, inadequate management of the airways, and poor management of the transfer between hospitals. IMPLICATIONS--Regions should revise urgently their guidelines for optimal management and indications for neurosurgical referral to include children with severe head injuries and audit their systems of care for all patients with head injuries. PMID:2105782

  13. Scattering characteristics of high-resolution meteor head echoes detected at multiple frequencies

    NASA Astrophysics Data System (ADS)

    Close, S.; Oppenheim, M.; Hunt, S.; Dyrud, L.

    2002-10-01

    Meteor data collected at the Kwajalein Missile Range (KMR) during the peak of the 1998 Leonid storm comprise the only simultaneous observations of meteor head echoes and trails using seven frequencies (very high frequency (VHF), ultrahigh frequency (UHF), L-, S-, C-, Ka-, and W-band spanning 160 MHz to 95 GHz). The primary sensor was the ARPA Long-Range Tracking and Instrumentation Radar (ALTAIR) radar operating at 160 MHz with 30 m range resolution and 422 MHz with 7.5 m range resolution, including both interferometric and polarization capabilities. This paper presents an analysis of this high-resolution data set with the following results: First, these observations support the theory that head echo scattering arises from an ionized region with a density sufficiently high that its plasma frequency exceeds the radar frequency (overdense reflection). Second, radar cross section (RCS) decreases rapidly with decreasing wavelength because higher frequencies must penetrate further into the increasing density of the plasma surrounding the meteoroid to reach its reflection point. Third, head echo angle measurements indicate that most of the observed meteors are sporadics not originating from the Leonid radiant. Fourth, polarization ratios showed that head echo reflections result from plasmas with a circular cross section. Fifth, the highest RCS values are detected near 105 km altitude, where the meteoroid gives up the most kinetic energy during its decent. This paper presents the first analyses of a three-frequency head echo as well as the polarization ratios and RCS characteristics from numerous two-frequency head echoes, which will allow us to develop a better understanding of meteor physics.

  14. Factors Influencing Light Scattering in the Eye

    NASA Astrophysics Data System (ADS)

    Ikaunieks, G.; Ozolinsh, M.; Stepanovs, A.; Lejiete, V.; Reva, N.

    2009-01-01

    Our vision in the twilight or dark is strongly affected by the intraocular light scattering (straylight). Of especial importance is to assess this phenomenon in view of the night driving. The authors have studied the spectral dependence of retinal stray-light and estimated the possibility to reduce it with yellow filters and small apertures. For the measurements the direct compensation flicker method was used. The results show that this spectral dependence is close to Rayleigh's scattering (∝λ-4). As could be expected from the known data, the yellow filter should reduce retinal straylight, especially for blue light. However, in the experiments this scattering was not removed with such a filter but instead slightly increased. The optical apertures reduced light scattering in the eye, especially for red color.

  15. Uncertainties and correction methods when modeling passive scattering proton therapy treatment heads with Monte Carlo

    PubMed Central

    Bednarz, Bryan; Lu, Hsiao-Ming; Engelsman, Martijn; Paganetti, Harald

    2011-01-01

    Monte Carlo models of proton therapy treatment heads are being used to improve beam delivery systems and to calculate the radiation field for patient dose calculations. The achievable accuracy of the model depends on the exact knowledge of the treatment head geometry and time structure, the material characteristics, and the underlying physics. This work aimed at studying the uncertainties in treatment head simulations for passive scattering proton therapy. The sensitivities of spread-out Bragg peak (SOBP) dose distributions on material densities, mean ionization potentials, initial proton beam energy spread and spot size were investigated. An improved understanding of the nature of these parameters may help to improve agreement between calculated and measured SOBP dose distributions and to ensure that the range, modulation width, and uniformity are within clinical tolerance levels. Furthermore, we present a method to make small corrections to the uniformity of spread-out Bragg peaks by utilizing the time structure of the beam delivery. In addition, we re-commissioned the models of the two proton treatment heads located at our facility using the aforementioned correction methods presented in this paper. PMID:21478569

  16. Scattered radiation from dental metallic crowns in head and neck radiotherapy.

    PubMed

    Shimozato, T; Igarashi, Y; Itoh, Y; Yamamoto, N; Okudaira, K; Tabushi, K; Obata, Y; Komori, M; Naganawa, S; Ueda, M

    2011-09-01

    We aimed to estimate the scattered radiation from dental metallic crowns during head and neck radiotherapy by irradiating a jaw phantom with external photon beams. The phantom was composed of a dental metallic plate and hydroxyapatite embedded in polymethyl methacrylate. We used radiochromic film measurement and Monte Carlo simulation to calculate the radiation dose and dose distribution inside the phantom. To estimate dose variations in scattered radiation under different clinical situations, we altered the incident energy, field size, plate thickness, plate depth and plate material. The simulation results indicated that the dose at the incident side of the metallic dental plate was approximately 140% of that without the plate. The differences between dose distributions calculated with the radiation treatment-planning system (TPS) algorithms and the data simulation, except around the dental metallic plate, were 3% for a 4 MV photon beam. Therefore, we should carefully consider the dose distribution around dental metallic crowns determined by a TPS. PMID:21813962

  17. Examining Protective Factors and Risk Factors in Urban and Rural Head Start Preschoolers

    ERIC Educational Resources Information Center

    Bender, Stacy L.; Fedor, Megan C.; Carlson, John S.

    2011-01-01

    This study examined a comprehensive screening model within children attending Head Start programs from urban (n = 232) and rural (n = 231) communities. The Devereux Early Childhood Assessment (DECA; LeBuffe & Naglieri, 1999) was used to measure social-emotional protective factors (i.e., Total Protective Factors [TPF]) and risk factors (i.e.,…

  18. Scattering form factors for self-assembled network junctions

    NASA Astrophysics Data System (ADS)

    Foster, T.; Safran, S. A.; Sottmann, T.; Strey, R.

    2007-11-01

    The equilibrium microstructures in microemulsions and other self-assembled systems show complex, connected shapes such as symmetric bicontinuous spongelike structures and asymmetric bicontinuous networks formed by cylinders interconnected at junctions. In microemulsions, these cylinder network microstructures may mediate the structural transition from a spherical or globular phase to the bicontinuous microstructure. To understand the structural and statistical properties of such cylinder network microstructures as measured by scattering experiments, models are needed to extract the real-space structure from the scattering data. In this paper, we calculate the scattering functions appropriate for cylinder network microstructures. We focus on such networks that contain a high density of network junctions that connect the cylindrical elements. In this limit, the network microstructure can be regarded as an assembly of randomly oriented, closed packed network junctions (i.e., the cylinder scattering contributions are neglected). Accordingly, the scattering spectrum of the network microstructure can be calculated as the product of the junction number density, the junction form factor, which describes the scattering from the surface of a single junction, and a structure factor, which describes the local correlations of different junctions due to junction interactions (including their excluded volume). This approach is applied to analyze the scattering data from a bicontinuous microemulsion with equal volumes of water and oil. In a second approach, we included the cylinder scattering contribution in the junction form factor by calculating the scattering intensity of Y junctions to which three rods with spherical cross section are attached. The respective theoretical predictions are compared with results of neutron scattering measurements on a water-in-oil microemulsion with a connected microstructure.

  19. The separation of the head and phantom scatter components from a phase space description

    NASA Astrophysics Data System (ADS)

    Esteban Sanz, Darío; Enrico Nelli, Flavio

    2004-09-01

    The formalism based on phantom and collimator scatter factors for high energy photon beams is deduced using a phase space description. The phantom scatter factors (Sp) depend on the field size and shape at the level of the phantom and are generally considered independent of the collimation details used to form the desired field provided the effect of contaminant electrons can be neglected. As demonstrated in this work, this behaviour leads to the applicability of the Clarkson method in irregular fields. However, for a given field formed with a tertiary collimator it is not a priori clear that the variations of extrafocal radiation due to secondary collimator setting do not affect the phantom scatter correction factors. In fact, the extrafocal radiation has a lower mean energy than that of unscattered photons, and this radiation can reach points well outside the radiation field increasing the irradiated phantom volume. Besides, transmission through the blocks contributes to phantom scatter. Therefore, for a given block-defined field, the associated phantom scatter dose, per unit of fluence in air on the central axis, should in principle increase when enlarging the secondary collimator field. To confirm this, isocentric Sp data for 6 MV photons were measured at 10 cm depth in water, reducing with cerrobend blocks several fields formed with the secondary collimators. In particular, when a 30 × 30 cm2 collimator field is reduced with blocks to a 7 × 7 cm2 field, the dose per unit of fluence in air is 1.4% higher than that of the square collimator field equating the given block field. Our calculations indicate that in this case the block transmission accounts for only 0.2% of this increment, showing that the remaining effect is due to extrafocal radiation. As a concluding remark, this work contributes to a better understanding of the classical Clarkson method for irregular fields giving, additionally, a formal interpretation of the commonly used quantities.

  20. X-Ray Form Factor, Attenuation and Scattering Tables

    National Institute of Standards and Technology Data Gateway

    SRD 66 X-Ray Form Factor, Attenuation and Scattering Tables (Web, free access)   This database collects tables and graphs of the form factors, the photoabsorption cross section, and the total attenuation coefficient for any element (Z <= 92).

  1. Scatter estimation and removal of anti-scatter grid-line artifacts from anthropomorphic head phantom images taken with a high resolution image detector

    NASA Astrophysics Data System (ADS)

    Rana, R.; Jain, A.; Shankar, A.; Bednarek, D. R.; Rudin, S.

    2016-03-01

    In radiography, one of the best methods to eliminate image-degrading scatter radiation is the use of anti-scatter grids. However, with high-resolution dynamic imaging detectors, stationary anti-scatter grids can leave grid-line shadows and moiré patterns on the image, depending upon the line density of the grid and the sampling frequency of the x-ray detector. Such artifacts degrade the image quality and may mask small but important details such as small vessels and interventional device features. Appearance of these artifacts becomes increasingly severe as the detector spatial resolution is improved. We have previously demonstrated that, to remove these artifacts by dividing out a reference grid image, one must first subtract the residual scatter that penetrates the grid; however, for objects with anatomic structure, scatter varies throughout the FOV and a spatially differing amount of scatter must be subtracted. In this study, a standard stationary Smit-Rontgen X-ray grid (line density - 70 lines/cm, grid ratio - 13:1) was used with a high-resolution CMOS detector, the Dexela 1207 (pixel size - 75 micron) to image anthropomorphic head phantoms. For a 15 x 15cm FOV, scatter profiles of the anthropomorphic head phantoms were estimated then iteratively modified to minimize the structured noise due to the varying grid-line artifacts across the FOV. Images of the anthropomorphic head phantoms taken with the grid, before and after the corrections, were compared demonstrating almost total elimination of the artifact over the full FOV. Hence, with proper computational tools, antiscatter grid artifacts can be corrected, even during dynamic sequences.

  2. Analytical evaluation of atomic form factors: Application to Rayleigh scattering

    SciTech Connect

    Safari, L.; Santos, J. P.; Amaro, P.; Jänkälä, K.; Fratini, F.

    2015-05-15

    Atomic form factors are widely used for the characterization of targets and specimens, from crystallography to biology. By using recent mathematical results, here we derive an analytical expression for the atomic form factor within the independent particle model constructed from nonrelativistic screened hydrogenic wave functions. The range of validity of this analytical expression is checked by comparing the analytically obtained form factors with the ones obtained within the Hartee-Fock method. As an example, we apply our analytical expression for the atomic form factor to evaluate the differential cross section for Rayleigh scattering off neutral atoms.

  3. An effective field theory for forward scattering and factorization violation

    NASA Astrophysics Data System (ADS)

    Rothstein, Ira Z.; Stewart, Iain W.

    2016-08-01

    Starting with QCD, we derive an effective field theory description for forward scattering and factorization violation as part of the soft-collinear effective field theory (SCET) for high energy scattering. These phenomena are mediated by long distance Glauber gluon exchanges, which are static in time, localized in the longitudinal distance, and act as a kernel for forward scattering where | t| ≪ s. In hard scattering, Glauber gluons can induce corrections which invalidate factorization. With SCET, Glauber exchange graphs can be calculated explicitly, and are distinct from graphs involving soft, collinear, or ultrasoft gluons. We derive a complete basis of operators which describe the leading power effects of Glauber exchange. Key ingredients include regulating light-cone rapidity singularities and subtractions which prevent double counting. Our results include a novel all orders gauge invariant pure glue soft operator which appears between two collinear rapidity sectors. The 1-gluon Feynman rule for the soft operator coincides with the Lipatov vertex, but it also contributes to emissions with ≥ 2 soft gluons. Our Glauber operator basis is derived using tree level and one-loop matching calculations from full QCD to both SCETII and SCETI. The one-loop amplitude's rapidity renormalization involves mixing of color octet operators and yields gluon Reggeization at the amplitude level. The rapidity renormalization group equation for the leading soft and collinear functions in the forward scattering cross section are each given by the BFKL equation. Various properties of Glauber gluon exchange in the context of both forward scattering and hard scattering factorization are described. For example, we derive an explicit rule for when eikonalization is valid, and provide a direct connection to the picture of multiple Wilson lines crossing a shockwave. In hard scattering operators Glauber subtractions for soft and collinear loop diagrams ensure that we are not sensitive to

  4. Modulation of Factors Affecting Optic Nerve Head Astrocyte Migration

    PubMed Central

    Miao, Haixi; Crabb, Andrea W.; Hernandez, M. Rosario

    2010-01-01

    Purpose. The authors investigated the role of myosin light chain kinase (MYLK) and transforming growth factor beta (TGFβ) receptor pathways in optic nerve head (ONH) astrocyte migration. They further investigated how the expression of these genes is altered by elevated hydrostatic pressure (HP). Methods. PCR was used to determine the isoforms of MYLK expressed in ONH astrocytes. siRNAs against MYLK (all isoforms) and TGFβ receptor 2 (TGFBR2) were prepared and tested for effects on the migration of cultured ONH astrocytes. Finally, the effects of elevated HP (24–96 hours) on the expression of MYLK isoforms and selected TGFβ pathway components were measured. Results. Multiple isoforms of MYLK are present in ONH astrocytes from Caucasian (CA) and African American (AA) donors. Both populations express the short form (MYLK-130) and the long form (MYLK-210) of MYLK and a splicing variant within MYLK-210. MYLK-directed siRNA decreased MYLK expression and cell migration compared with control siRNA. siRNA directed against TGFβ receptor 2 also decreased cell migration compared with control and decreased extracellular matrix genes regulated by TGFβ signaling. Elevated HP increased the expression of MYLK-130 and MYLK-210 in both populations of astrocytes. However, TGFβ2 was uniquely upregulated by exposure to elevated HP in CA compared with AA astrocytes. Conclusions. Differential expression of TGFβ pathway genes and MYLK isoforms observed in populations of glaucomatous astrocytes applies to the elevated HP model system. MYLK may be a new target for intervention in glaucoma to alter reactive astrocyte migration in the ONH. PMID:20375339

  5. Ranking Medical Subject Headings using a factor graph model

    PubMed Central

    Wei, Wei; Demner-Fushman, Dina; Wang, Shuang; Jiang, Xiaoqian; Ohno-Machado, Lucila

    2015-01-01

    Automatically assigning MeSH (Medical Subject Headings) to articles is an active research topic. Recent work demonstrated the feasibility of improving the existing automated Medical Text Indexer (MTI) system, developed at the National Library of Medicine (NLM). Encouraged by this work, we propose a novel data-driven approach that uses semantic distances in the MeSH ontology for automated MeSH assignment. Specifically, we developed a graphical model to propagate belief through a citation network to provide robust MeSH main heading (MH) recommendation. Our preliminary results indicate that this approach can reach high Mean Average Precision (MAP) in some scenarios. PMID:26306236

  6. Socioeconomic status, family background and other key factors influence the management of head lice in Norway.

    PubMed

    Rukke, Bjørn Arne; Soleng, Arnulf; Lindstedt, Heidi Heggen; Ottesen, Preben; Birkemoe, Tone

    2014-05-01

    How head lice infestations are managed by households is an important but generally neglected issue in head lice research. In the present study, we investigate actions taken against head lice by Norwegian households in association with socioeconomic status, family background, school-related variables and other key factors. Repeat questionnaires distributed to caretakers of the same elementary school children during a 2-year period enabled us to study both previous head lice management and any changes in this management through time. Households from 12 schools spanning the main socioeconomic variation found in Norway participated in the study. All students with active head lice infestation were treated in the four investigated periods. Most caretakers used a thorough head lice checking technique and informed others of own infestation. Checking frequency was low as most children were inspected less than monthly. The best determinant of increased checking frequency and thoroughness was personal experience with head lice. The increased awareness, however, seemed to be somewhat short-lived, as there was a decrease in checking frequency and thoroughness within 1 year after infestation. Personal experience with head lice also increased general knowledge related to the parasite. Parents born in developing countries checked their children for head lice more frequently, although less thoroughly, informed fewer contacts when infested, used pediculicides preventively more often and knew less about head lice than parents born in developed countries. Households with highly educated mothers had a lower checking frequency, but their knowledge and willingness to inform others was high. Single parents were more concerned about economic costs and kept children home from school longer while infested than other parents. As head lice management varied among socioeconomic groups and with parental background, differentiated advice should be considered in the control of head lice. The

  7. Wide Angle Compton Scattering within the SCET factorization Framework

    NASA Astrophysics Data System (ADS)

    Kivel, Nikolay

    2016-03-01

    Existing data for the electromagnetic proton form factors and for the cross section of the wide angle Compton scattering (WACS) show that the hard two-gluon exchange mechanism (collinear factorization) is still not applicable in the kinematical region where Mandelstam variables s ~ -t ~ -u are about few GeV2. On the other hand these observables can be described in phenomenological models where spectator quarks are soft which assumes a large contribution due to the soft-overlap mechanism. It turns out that the simple QCD factorization picture is not complete and must also include the soft-overlap contribution which can be described as a certain matrix element in the soft collinear effective theory (SCET). Then the leading power contribution to WACS amplitude is described as a sum of the hard- and soft-spectator contributions. The existing experimental data allows one to check certain conclusions based on the assumption about dominant role of the soft-spectator mechanism.

  8. SU-E-T-08: A Convolution Model for Head Scatter Fluence in the Intensity Modulated Field

    SciTech Connect

    Chen, M; Mo, X; Chen, Y; Parnell, D; Key, S; Olivera, G; Galmarini, W; Lu, W

    2014-06-01

    Purpose: To efficiently calculate the head scatter fluence for an arbitrary intensity-modulated field with any source distribution using the source occlusion model. Method: The source occlusion model with focal and extra focal radiation (Jaffray et al, 1993) can be used to account for LINAC head scatter. In the model, the fluence map of any field shape at any point can be calculated via integration of the source distribution within the visible range, as confined by each segment, using the detector eye's view. A 2D integration would be required for each segment and each fluence plane point, which is time-consuming, as an intensity-modulated field contains typically tens to hundreds of segments. In this work, we prove that the superposition of the segmental integrations is equivalent to a simple convolution regardless of what the source distribution is. In fact, for each point, the detector eye's view of the field shape can be represented as a function with the origin defined at the point's pinhole reflection through the center of the collimator plane. We were thus able to reduce hundreds of source plane integration to one convolution. We calculated the fluence map for various 3D and IMRT beams and various extra-focal source distributions using both the segmental integration approach and the convolution approach and compared the computation time and fluence map results of both approaches. Results: The fluence maps calculated using the convolution approach were the same as those calculated using the segmental approach, except for rounding errors (<0.1%). While it took considerably longer time to calculate all segmental integrations, the fluence map calculation using the convolution approach took only ∼1/3 of the time for typical IMRT fields with ∼100 segments. Conclusions: The convolution approach for head scatter fluence calculation is fast and accurate and can be used to enhance the online process.

  9. SU-E-I-55: The Contribution to Skin Dose Due to Scatter From the Patient Table and the Head Holder During Fluoroscopy

    SciTech Connect

    Islam, N; Xiong, Z; Vijayan, S; Rudin, S; Bednarek, D

    2015-06-15

    Purpose: To determine contributions to skin dose due to scatter from the table and head holder used during fluoroscopy, and also to explore alternative design material to reduce the scatter dose. Methods: Measurements were made of the primary and scatter components of the xray beam exiting the patient table and a cylindrical head holder used on a Toshiba Infinix c-arm unit as a function of kVp for the various beam filters on the machine and for various field sizes. The primary component of the beam was measured in air with the object placed close to the x-ray tube with an air gap between it and a 6 cc parallel-plate ionization chamber and with the beam collimated to a size just larger than the chamber. The primary plus scatter radiation components were measured with the object moved to a position in the beam next to the chamber for larger field sizes. Both sets of measurements were preformed while keeping the source-to-chamber distance fixed. The scatter fraction was estimated by taking the ratio of the difference between the two measurements and the reading that included both primary and scatter. Similar measurements were also made for a 2.3 cm thick Styrofoam block which could substitute for the patient support. Results: The measured scatter fractions indicate that the patient table as well as the head holder contributes an additional 10–16% to the patient entrance dose depending on field size. Forward scatter was reduced with the Styrofoam block so that the scatter fraction was about 4–5%. Conclusion: The results of this investigation demonstrated that scatter from the table and head holder used in clinical fluoroscopy contribute substantially to the skin dose. The lower contribution of scatter from Styrofoam suggests that there is an opportunity to redesign patient support accessories to reduce the skin dose. Partial support from NIH grant R01EB002873 and Toshiba Medical Systems Corporation Equipment Grant.

  10. Altered sensory-motor control of the head as an etiological factor in space-motion sickness

    NASA Technical Reports Server (NTRS)

    Lackner, J. R.; DiZio, P.

    1989-01-01

    Mechanical unloading during head movements in weightlessness may be an etiological factor in space-motion sickness. We simulated altered head loading on Earth without affecting vestibular stimulation by having subjects wear a weighted helmet. Eight subjects were exposed to constant velocity rotation about a vertical axis with direction reversals every 60 sec. for eight reversals with the head loaded and eight with the head unloaded. The severity of motion sickness elicited was significantly higher when the head was loaded. This suggests that altered sensory-motor control of the head is also an etiological factor in space-motion sickness.

  11. Longitudinal electron scattering form factors for 54,56Fe

    NASA Astrophysics Data System (ADS)

    Salman, A. D.; Kadhim, D. R.

    2014-09-01

    In this paper, inelastic longitudinal electron scattering form factors for C2 transition have been studied in 54Fe and 56Fe with the aid of shell model calculations. The GX1 effective interaction for the fp-shell is used with the nucleon-nucleon realistic interaction Michigan three-range Yukawa and Modified surface delta interaction as a two-body interactions. The core polarization effects is taken into account through the first-order perturbation theory with the effective charge, which is taken to the proton and the neutron. The effective charge along with the core effects up to 6 ℏw enhanced the calculation very well and improving good agreement with the experimental data.

  12. Strange vector form factors from parity-violating electron scattering

    SciTech Connect

    Kent Paschke, Anthony Thomas, Robert Michaels, David Armstrong

    2011-06-01

    The simplest models might describe the nucleon as 3 light quarks, but this description would be incomplete without inclusion of the sea of glue and qbar q pairs which binds it. Early indications of a particularly large contribution from strange quarks in this sea to the spin and mass of the nucleon motivated an experimental program examining the role of these strange quarks in the nucleon vector form factors. The strangeness form factors can be extracted from the well-studied electromagnetic structure of the nucleon using parity-violation in electron-nuclear scattering to isolate the effect of the weak interaction. With high luminosity and polarization, and a very stable beam due to its superconducting RF cavities, CEBAF at Jefferson Lab is a precision instrument uniquely well suited to the challenge of measurements of the small parity-violating asymmetries. The techniques and results of the two major Jefferson Lab experimental efforts in parity-violation studies, HAPPEX and G0, as well as efforts to describe the strange form factors in QCD, will be reviewed.

  13. Incidence of Etiologic Factors in Squamous Cell Carcinoma of Head and Neck in Ahvaz

    PubMed Central

    Nikakhlagh, Soheila; Saki, Nader; shoar, Mahmood Hekmat; Sartipipor, Amin; Saki, Sara

    2012-01-01

    Introduction: Squamous cell carcinoma (SCC) is the most common head and neck malignancy. Smoking, alcohol consumption, viral infections, exposure, oral hygiene, and dietary, genetic, and occupational factors are the most important etiologic factors. The aim of this study was determining the incidence of etiologic factors in head and neck SCC. Materials and Methods: This is a cross-sectional survey study for the determination of the etiologic factors of head and neck squamous cell carcinoma over a five-year period in the Otolaryngology Department of the Imam Khomeini & Golestan hospitals in Ahwaz. Results: 176 patients, comprising 151(85.8%) men and 25(14.2%) women, were studied. Overall mean age was 67.2 years. 148 (84.1%) patients were smokers. prolong exposure to chemical fertilizer in 101 (57.4%) patients, Sun exposure in 21 (11.9%) patients, Low socioeconomic status in 124 (70.5%) patients, poor oral hygiene in 128 (72.7%) patients, high intake of hot tea drinking in 84 (47.7%) patients and malignancies in family in 12 (6.8%) patients were the most frequent risk factors. 17 (9.6%) patients have had opioid addiction and HPV was positive in 7 (3.9%) patients by PCR. Conclusion: According to this study, tobacco smoking was the most important etiologic factor and had a strong effect on risk of head and neck squamous cell carcinoma. Other factors are also important and need more research study. PMID:24303391

  14. A dynamic factor modeling framework for analyzing multiple groundwater head series simultaneously

    NASA Astrophysics Data System (ADS)

    Berendrecht, W. L.; van Geer, F. C.

    2016-05-01

    In this paper we present an approach in which we combine a dynamic factor model (DFM) and predefined response functions to analyze a set of groundwater head series simultaneously. Each groundwater head series is decomposed into: (a) one or more deterministic components as a response to known driving forces, (b) one or more common dynamic factors, representing spatial patterns not related to any of the input series and (c) one specific dynamic factor for each groundwater head series, describing unique variation for that series. The approach reduces the degrees of freedom for each response function, enables the application to irregular observed data, and exploits the correlation between residual series of a set of groundwater head series. The common dynamic factors may be interpreted as spatial patterns due to e.g. limitations in the model specification or concept, spatially correlated errors in input variables, or driving forces which have not been included in the model. In the latter case the model can be applied in the context of an alarming system, e.g. to monitor regional trends. The specific dynamic factor depicts the variation of a particular groundwater head series that cannot be related to any other time series of the set nor to any input series. Therefore the specific dynamic factor is suitable for analyzing local variations and detecting incidental measurement errors, for example in a quality control procedure. The DFM framework is illustrated with a set of 8 groundwater head series and applied for filling gaps in time series, reconstructing high-frequency data, and detecting outliers.

  15. Characterisation of hydraulic head changes and aquifer properties in the London Basin using Persistent Scatterer Interferometry ground motion data

    NASA Astrophysics Data System (ADS)

    Bonì, R.; Cigna, F.; Bricker, S.; Meisina, C.; McCormack, H.

    2016-09-01

    In this paper, Persistent Scatterer Interferometry was applied to ERS-1/2 and ENVISAT satellite data covering 1992-2000 and 2002-2010 respectively, to analyse the relationship between ground motion and hydraulic head changes in the London Basin, United Kingdom. The integration of observed groundwater levels provided by the Environment Agency and satellite-derived displacement time series allowed the estimation of the spatio-temporal variations of the Chalk aquifer storage coefficient and compressibility over an area of ∼1360 km2. The average storage coefficient of the aquifer reaches values of 1 × 10-3 and the estimated average aquifer compressibility is 7.7 × 10-10 Pa-1 and 1.2 × 10-9 Pa-1 for the periods 1992-2000 and 2002-2010, respectively. Derived storage coefficient values appear to be correlated with the hydrogeological setting, where confined by the London Clay the storage coefficient is typically an order of magnitude lower than where the chalk is overlain by the Lambeth Group. PSI-derived storage coefficient estimates agree with the values obtained from pumping tests in the same area. A simplified one-dimensional model is applied to simulate the ground motion response to hydraulic heads changes at nine piezometers. The comparison between simulated and satellite-observed ground motion changes reveals good agreement, with errors ranging between 1.4 and 6.9 mm, and being 3.2 mm on average.

  16. Total scatter factors of small beams: A multidetector and Monte Carlo study

    PubMed Central

    Francescon, Paolo; Cora, Stefania; Cavedon, Carlo

    2008-01-01

    The scope of this study was to estimate total scatter factors (sc,p) of the three smallest collimators of the Cyberknife radiosurgery system (5–10 mm in diameter), combining experimental measurements and Monte Carlo simulation. Two microchambers, a diode, and a diamond detector were used to collect experimental data. The treatment head and the detectors were simulated by means of a Monte Carlo code in order to calculate correction factors for the detectors and to estimate total scatter factors by means of a consistency check between measurement and simulation. Results for the three collimators were: sc,p(5 mm)=0.677±0.004, sc,p(7.5 mm)=0.820±0.008, sc,p(10 mm)=0.871±0.008, all relative to the 60 mm collimator at 80 cm source-to-detector distance. The method also allows the full width at half maximum of the electron beam to be estimated; estimations made with different collimators and different detectors were in excellent agreement and gave a value of 2.1 mm. Correction factors to be applied to the detectors for the measurement of sc,p were consistent with a prevalence of volume effect for the microchambers and the diamond and a prevalence of scattering from high-Z material for the diode detector. The proposed method is more sensitive to small variations of the electron beam diameter with respect to the conventional method used to commission Monte Carlo codes, i.e., by comparison with measured percentage depth doses (PDD) and beam profiles. This is especially important for small fields (less than 10 mm diameter), for which measurements of PDD and profiles are strongly affected by the type of detector used. Moreover, this method should allow sc,p of Cyberknife systems different from the unit under investigation to be estimated without the need for further Monte Carlo calculation, provided that one of the microchambers or the diode detector of the type used in this study are employed. The results for the diamond are applicable only to the specific detector

  17. Total scatter factors of small beams: A multidetector and Monte Carlo study

    SciTech Connect

    Francescon, Paolo; Cora, Stefania; Cavedon, Carlo

    2008-02-15

    The scope of this study was to estimate total scatter factors (s{sub c,p}) of the three smallest collimators of the Cyberknife radiosurgery system (5-10 mm in diameter), combining experimental measurements and Monte Carlo simulation. Two microchambers, a diode, and a diamond detector were used to collect experimental data. The treatment head and the detectors were simulated by means of a Monte Carlo code in order to calculate correction factors for the detectors and to estimate total scatter factors by means of a consistency check between measurement and simulation. Results for the three collimators were: s{sub c,p}(5 mm)=0.677{+-}0.004, s{sub c,p}(7.5 mm)=0.820{+-}0.008, s{sub c,p}(10 mm)=0.871{+-}0.008, all relative to the 60 mm collimator at 80 cm source-to-detector distance. The method also allows the full width at half maximum of the electron beam to be estimated; estimations made with different collimators and different detectors were in excellent agreement and gave a value of 2.1 mm. Correction factors to be applied to the detectors for the measurement of s{sub c,p} were consistent with a prevalence of volume effect for the microchambers and the diamond and a prevalence of scattering from high-Z material for the diode detector. The proposed method is more sensitive to small variations of the electron beam diameter with respect to the conventional method used to commission Monte Carlo codes, i.e., by comparison with measured percentage depth doses (PDD) and beam profiles. This is especially important for small fields (less than 10 mm diameter), for which measurements of PDD and profiles are strongly affected by the type of detector used. Moreover, this method should allow s{sub c,p} of Cyberknife systems different from the unit under investigation to be estimated without the need for further Monte Carlo calculation, provided that one of the microchambers or the diode detector of the type used in this study are employed. The results for the diamond are

  18. Electromagnetic Form Factors of the Nucleon and Compton Scattering

    SciTech Connect

    Charles Hyde-Wright; Cornelis De Jager

    2004-12-01

    We review the experimental and theoretical status of elastic electron scattering and elastic low-energy photon scattering (with both real and virtual photons) from the nucleon. As a consequence of new experimental facilities and new theoretical insights, these subjects are advancing with unprecedented precision. These reactions provide many important insights into the spatial distributions and correlations of quarks in the nucleon.

  19. Factors affecting the aluminium content of human femoral head and neck.

    PubMed

    Zioła-Frankowska, Anetta; Dąbrowski, Mikołaj; Kubaszewski, Łukasz; Rogala, Piotr; Frankowski, Marcin

    2015-11-01

    Tissues for the study were obtained intraoperatively during hip replacement procedures from 96 patients. In all the cases, the indication for this treatment was primary or secondary degenerative changes in the hip joint. The subject of the study was the head and neck of the femur, resected in situ. Aluminium concentrations measured in femoral head and neck samples from patients aged between 25 and 91 were varied. Statistical methods were applied to determine the variations in relation to the parameters from the background survey. Significant differences in the aluminium content of femoral head samples were observed between patients under and over 60 years of age. Based on the results, it was confirmed that the aluminium accumulates in bones over a lifetime. The study showed that the content of aluminium in the head and neck of the femur depends on the factors such as: type of medicines taken, contact with chemicals at work, differences in body anatomy and sex. The study on the levels of aluminium in bones and the factors affecting its concentration is a valuable source of information for further research on the role of aluminium in bone diseases. Based on the investigations, it was found that the GF-AAS technique is the best analytical tool for routine analysis of aluminium in complex matrix samples. The use of femoral heads in the investigations was approved by the Bioethics Committee of the University of Medical Sciences in Poznań (Poland). PMID:26341598

  20. Epidemiology of Pediatric Closed Head Injury: Incidence, Clinical Characteristics, and Risk Factors.

    ERIC Educational Resources Information Center

    Goldstein, Felicia C.; Levin, Harvey S.

    1987-01-01

    The paper reviews the epidemiology of pediatric closed head injury. Incidence rates, etiologic/pathophysiologic correlates, and associated risk factors are discussed. Suggestions offered for future research concern relationships among age, etiology, and pathophysiology in outcome studies and premorbid measures of personality/intellectual…

  1. Individual Factors Associated with Professional Development Training Outcomes of the Head Start REDI Program

    ERIC Educational Resources Information Center

    Domitrovich, Celene E.; Gest, Scott D.; Gill, Sukhdeep; Jones, Damon; DeRousie, Rebecca Sanford

    2009-01-01

    Research Findings: This study examined factors associated with process and content outcomes of the training provided in the context of Head Start REDI (Research based Developmentally Informed), a preschool curriculum designed to enhance the quality of interactions (social-emotional and language-literacy) between teachers and children. REDI…

  2. Assessment of Factors Resulting in Abuse Evaluations in Young Children with Minor Head Trauma

    ERIC Educational Resources Information Center

    Anderst, James D.

    2008-01-01

    Objective: The primary objective was to determine which of the examined factors prompted physicians to initiate a further abuse evaluation in young children with minor head injury. The recording of important historical elements in the charts of these patients was also evaluated. Methods: Charts of 349 children less than 3 years of age with minor…

  3. Factors that Impact West Virginia Head Start Parental Involvement in Early Literacy

    ERIC Educational Resources Information Center

    Clausell, Arlene Midget

    2010-01-01

    The research problem is: Many parents are not involved in their children's early literacy education. Some Head Start parents experience issues that keep them from teaching their children early literacy skills. The research questions were: What are the factors for parental involvement in the support of early literacy skill development for their…

  4. Family Risks and Protective Factors: Pathways to Early Head Start Toddlers' Social-Emotional Functioning

    ERIC Educational Resources Information Center

    Vick Whittaker, Jessica E.; Harden, Brenda Jones; See, Heather M.; Meisch, Allison D.; Westbrook, T'Pring R.

    2011-01-01

    Early Head Start children may be more likely to exhibit difficulties with social-emotional functioning due to the high-risk environments in which they live. However, positive parenting may serve as a protective factor against the influence of risk on children's outcomes. The current study examines the effects of contextual and proximal risks on…

  5. Factors Associated with Head Start Staff Participation in Classroom-Based Professional Development

    ERIC Educational Resources Information Center

    Trivette, Carol M.; Raab, Melinda; Dunst, Carl J.

    2014-01-01

    Factors associated with Head Start staff participation in a classroom-based professional development project to promote their use of evidence-based child learning opportunity practices and evidence-based responsive teaching procedures were examined in a study of 36 teachers and teacher assistants in 19 different classrooms. The factors…

  6. Surgical site infection in clean-contaminated head and neck cancer surgery: risk factors and prognosis.

    PubMed

    Hirakawa, Hitoshi; Hasegawa, Yasuhisa; Hanai, Nobuhiro; Ozawa, Taijiro; Hyodo, Ikuo; Suzuki, Mikio

    2013-03-01

    Since new treatment strategies, such as chemoradiotherapy, have been introduced for head and neck cancer, a higher number of unknown factors may be involved in surgical site infection in clean-contaminated head and neck cancer surgery. The aim of the present study was to clarify the risk factors of surgical site infection in clean-contaminated surgery for head and neck cancer and the prognosis of patients with surgical site infection. Participants were 277 consecutive patients with head and neck cancer who underwent clean-contaminated surgery for primary lesions at the Aichi Cancer Center over a 60-month period. A total of 22 putative risk factors were recorded in each patient and statistically analyzed to elucidate surgical site infection related factors. Surgical site infection was observed in 92 (32.1 %) of 277 cases. Univariate analysis indicated that alcohol consumption, T classification, neck dissection, reconstructive procedure, and chemoradiotherapy were significantly associated with surgical site infection. Multiple logistic regression analysis identified two independent risk factors for surgical site infection: reconstructive surgery (p = 0.04; odds ratio (OR) 1.77) and chemoradiotherapy (p = 0.01; OR 1.93). In spite of surgical site infection, the five-year overall survival rate of patients with surgical site infection was not significantly different from those without surgical site infection. Although surgical site infection did not impact the overall survival of patients with surgical procedures, head and neck surgeons should pay attention to patients with previous chemoradiotherapy as well as to those with a high risk of surgical site infection requiring reconstructive surgery. PMID:22865106

  7. Practical and adequate approach to modeling light propagation in an adult head with low-scattering regions by use of diffusion theory.

    PubMed

    Koyama, Tatsuya; Iwasaki, Atsushi; Ogoshi, Yosuke; Okada, Eiji

    2005-04-10

    A practical and adequate approach to modeling light propagation in an adult head with a low-scattering cerebrospinal fluid (CSF) region by use of diffusion theory was investigated. The diffusion approximation does not hold in a nonscattering or low-scattering regions. The hybrid radiosity-diffusion method was adopted to model the light propagation in the head with a nonscattering region. In the hybrid method the geometry of the nonscattering region is acquired as a priori information. In reality, low-level scattering occurs in the CSF region and may reduce the error caused by the diffusion approximation. The partial optical path length and the spatial sensitivity profile calculated by the finite-element method agree well with those calculated by the Monte Carlo method in the case in which the transport scattering coefficient of the CSF layer is greater than 0.3 mm(-1). Because it is feasible to assume that the transport scattering coefficient of a CSF layer is 0.3 mm(-1), it is practical to adopt diffusion theory to the modeling of light propagation in an adult head as an alternative to the hybrid method. PMID:15835358

  8. Practical and adequate approach to modeling light propagation in an adult head with low-scattering regions by use of diffusion theory

    NASA Astrophysics Data System (ADS)

    Koyama, Tatsuya; Iwasaki, Atsushi; Ogoshi, Yosuke; Okada, Eiji

    2005-04-01

    A practical and adequate approach to modeling light propagation in an adult head with a low-scattering cerebrospinal fluid (CSF) region by use of diffusion theory was investigated. The diffusion approximation does not hold in a nonscattering or low-scattering regions. The hybrid radiosity-diffusion method was adopted to model the light propagation in the head with a nonscattering region. In the hybrid method the geometry of the nonscattering region is acquired as a priori information. In reality, low-level scattering occurs in the CSF region and may reduce the error caused by the diffusion approximation. The partial optical path length and the spatial sensitivity profile calculated by the finite-element method agree well with those calculated by the Monte Carlo method in the case in which the transport scattering coefficient of the CSF layer is greater than 0.3 mm^-1. Because it is feasible to assume that the transport scattering coefficient of a CSF layer is 0.3 mm^-1, it is practical to adopt diffusion theory to the modeling of light propagation in an adult head as an alternative to the hybrid method.

  9. Robustness of the fractal regime for the multiple-scattering structure factor

    NASA Astrophysics Data System (ADS)

    Katyal, Nisha; Botet, Robert; Puri, Sanjay

    2016-08-01

    In the single-scattering theory of electromagnetic radiation, the fractal regime is a definite range in the photon momentum-transfer q, which is characterized by the scaling-law behavior of the structure factor: S(q) ∝ 1 /q df. This allows a straightforward estimation of the fractal dimension df of aggregates in Small-Angle X-ray Scattering (SAXS) experiments. However, this behavior is not commonly studied in optical scattering experiments because of the lack of information on its domain of validity. In the present work, we propose a definition of the multiple-scattering structure factor, which naturally generalizes the single-scattering function S(q). We show that the mean-field theory of electromagnetic scattering provides an explicit condition to interpret the significance of multiple scattering. In this paper, we investigate and discuss electromagnetic scattering by three classes of fractal aggregates. The results obtained from the TMatrix method show that the fractal scaling range is divided into two domains: (1) a genuine fractal regime, which is robust; (2) a possible anomalous scaling regime, S(q) ∝ 1 /qδ, with exponent δ independent of df, and related to the way the scattering mechanism uses the local morphology of the scatterer. The recognition, and an analysis, of the latter domain is of importance because it may result in significant reduction of the fractal regime, and brings into question the proper mechanism in the build-up of multiple-scattering.

  10. Purification of scatter factor, a fibroblast-derived basic protein that modulates epithelial interactions and movement.

    PubMed Central

    Gherardi, E; Gray, J; Stoker, M; Perryman, M; Furlong, R

    1989-01-01

    Scatter factor is a fibroblast-derived protein that causes separation of contiguous epithelial cells and increased local mobility of unanchored cells. Highly purified scatter factor has been obtained by a combination of ion-exchange and reverse-phase chromatography from serum-free medium conditioned by a ras-transformed clone (D4) of mouse NIH 3T3 fibroblasts. Under nonreducing conditions scatter factor has a pI of approximately 9.5 and migrates in SDS/polyacrylamide gels as a single band at approximately 62 kDa from which epithelial scatter activity can be recovered. Treatment with reducing agents destroys biological activity and is associated with the appearance of two major bands at approximately 57 and approximately 30 kDa. Whether both the 57-kDa and 30-kDa polypeptides are required for biological activity remains to be established. All the activities observed in crude medium conditioned by cells producing scatter factor are retained by highly purified preparations of scatter factor. These include (i) increased local movement, modulation of morphology, and inhibition of junction formation by single epithelial cells and (ii) disruption of epithelial interactions and cell scattering from preformed epithelial sheets. These changes occur with picomolar concentrations of purified scatter factor and without an effect on cell growth. Images PMID:2527367

  11. Comparing the quality of passively-scattered proton and photon tomotherapy plans for brain and head and neck disease sites

    NASA Astrophysics Data System (ADS)

    Kainz, Kristofer; Firat, Selim; Wilson, J. Frank; Schultz, Christopher; Siker, Malika; Wang, Andrew; Olson, Dan; Li, X. Allen

    2015-03-01

    We compare the quality of photon IMRT (helical tomotherapy) with classic proton plans for brain, head and neck tumors, in terms of target dose uniformity and conformity along with organ-at-risk (OAR) sparing. Plans were created for twelve target volumes among eight cases. All patients were originally planned and treated using helical tomotherapy. Proton plans were generated using a passively-scattered beam model with a maximum range of 32 g cm-2 (225 MeV), range modulation in 0.5 g cm-2 increments and range compensators with 4.8 mm milling tool diameters. All proton plans were limited to two to four beams. Plan quality was compared using uniformity index (UI), conformation number (CN) and a EUD-based plan quality index (fEUD). For 11 of the 12 targets, UI was improved for the proton plan; on average, UI was 1.05 for protons versus 1.08 for tomotherapy. For 7 of the 12 targets, the tomotherapy plan exhibited more favorable CN. For proximal OARs, the improved dose conformity to the target volume from tomotherapy led to a lower maximum dose. For distal OARs, the maximum dose was much lower for proton plans. For 6 of the 8 cases, near-total avoidance for distal OARs provided by protons leads to improved fEUD. However, if distal OARs are excluded in the fEUD calculation, the proton plans exhibit better fEUD in only 3 of the 8 cases. The distal OAR sparing and target dose uniformity are generally better with passive-scatter proton planning than with photon tomotherapy; proton therapy may be preferred if the clinician deems those attributes critical. However, tomotherapy may serve equally as well as protons for cases where superior target dose conformity from tomotherapy leads to plan quality nearly identical to or better than protons and for cases where distal OAR sparing is not concerning.

  12. Aspirin as a risk factor for hemorrhage in patients with head injuries.

    PubMed

    Reymond, M A; Marbet, G; Radü, E W; Gratzl, O

    1992-01-01

    The role of aspirin as a risk factor in the occurrence of intracranial bleeding following head injury was investigated. Chronic subdural hematoma appears to be a suitable model for the evaluation of risk factors in the development of hemorrhage. The most common risk factors found in our study were, apart from age, chronic alcohol abuse (28%), consumption of cumarin-derivates (21%), aspirin (13%), and heparin (5%). A patient undergoing aspirin treatment must be considered at risk of development of chronic subdural hematoma. Aspirin should not be prescribed to patients with post-traumatic headaches. PMID:1584433

  13. Endothelial derived factors inhibit anoikis of head and neck cancer stem cells

    PubMed Central

    Campos, Marcia S.; Neiva, Kathleen G.; Meyers, Kristy A.; Krishnamurthy, Sudha; Nör, Jacques E.

    2011-01-01

    Recent evidence demonstrated that cancer stem cells reside in close proximity to blood vessels in human head and neck squamous cell carcinomas (HNSCC). These findings suggest the existence of a supporting perivascular niche for cancer stem cells. Objective The purpose of this study was to evaluate the effect of endothelial cell-secreted factors on the behavior of head and neck cancer stem-like cells (HNCSC). Materials and methods HNCSC were identified by sorting UM-SCC-22A (cell line derived from a primary squamous cell carcinoma of the oropharynx) and UM-SCC-22B (derived from the metastatic lymph node of the same patient) for CD44 expression and ALDH (aldehyde dehydrogenase) activity. HNCSC (ALDH+CD44+) and control (ALDH−CD44−) cells were cultured in ultra-low attachment plates in presence of conditioned medium from primary human endothelial cells. Results ALDH+CD44+ generated more orospheres than control cells when cultured in suspension. The growth factor milieu secreted by endothelial cells protected HNCSC against anoikis. Mechanistic studies revealed that endothelial cell-secreted vascular endothelial growth factor (VEGF) induces proliferation of HNCSC derived from primary UM-SCC-22A, but not from the metastatic UM-SCC-22B. Likewise, blockade of VEGF abrogated endothelial cell-induced Akt phosphorylation in HNCSC derived from UM-SCC-22A while it had a modest effect in Akt phosphorylation in HNCSC from UM-SCC-22B. Conclusion This study revealed that endothelial cells initiate a crosstalk that protect head and neck cancer stem cells against anoikis, and suggest that therapeutic interference with this crosstalk might be beneficial for patients with head and neck cancer. PMID:22014666

  14. Experimental Determination of Dual-Wavelength Mie Lidar Geometric form Factor Combining Side-Scatter and Back-Scatter Signals

    NASA Astrophysics Data System (ADS)

    Wang, Zhenzhu; Tao, Zongming; Liu, Dong; Xie, Chenbo; Wang, Yingjian

    2016-06-01

    In theory, lidar overlap factor can be derived from the difference between the particle backscatter coefficient retrieved from lidar elastic signal without overlap correction and the actual particle backscatter coefficient, which can be obtained by other measured techniques. The side-scatter signal using a CCD camera is testified to be a powerful tool to detect the particle backscatter coefficient in near ground layer during night time. In experiment, by combining side-scatter and backscatter signals the geometric form factor for vertically-pointing Mie lidar in 532 nm channel is determined successfully, which is corrected by an iteration algorithm combining the retrieved particle backscatter coefficient using CCD sidescatter method and Fernald method. In this study, the method will be expanded to 1064 nm channel in dual-wavelength Mie lidar during routine campaigns. The experimental results in different atmosphere conditions demonstrated that the method present in this study is available in practice.

  15. Scattering from phase-separated vesicles. I. An analytical form factor for multiple static domains

    SciTech Connect

    Heberle, Frederick A.; Anghel, Vinicius N. P.; Katsaras, John

    2015-08-18

    This is the first in a series of studies considering elastic scattering from laterally heterogeneous lipid vesicles containing multiple domains. Unique among biophysical tools, small-angle neutron scattering can in principle give detailed information about the size, shape and spatial arrangement of domains. A general theory for scattering from laterally heterogeneous vesicles is presented, and the analytical form factor for static domains with arbitrary spatial configuration is derived, including a simplification for uniformly sized round domains. The validity of the model, including series truncation effects, is assessed by comparison with simulated data obtained from a Monte Carlo method. Several aspects of the analytical solution for scattering intensity are discussed in the context of small-angle neutron scattering data, including the effect of varying domain size and number, as well as solvent contrast. Finally, the analysis indicates that effects of domain formation are most pronounced when the vesicle's average scattering length density matches that of the surrounding solvent.

  16. The Role of Prothrombotic Factors in the Ocular Manifestations of Abusive and Non-Abusive Head Trauma: A Feasibility Study

    ERIC Educational Resources Information Center

    Yu, Anna; Stephens, Derek; Feldman, Brian M.; Parkin, Patricia C.; Kahr, Walter H. A.; Brandao, Leonardo R.; Shouldice, Michelle; Levin, Alex V.

    2012-01-01

    Objectives: Retinal hemorrhage is a cardinal manifestation of abusive head injury. Thrombophilia is relatively common in the general population and in adults can be associated with retinal hemorrhage. The specificity of retinal hemorrhage for abusive head trauma in the presence of prothrombotic factors, in particular following non-abusive head…

  17. Comment on ``Spectroscopic factors for bound s-wave states derived from neutron scattering lengths''

    NASA Astrophysics Data System (ADS)

    Barker, F. C.

    1997-12-01

    The procedure proposed by Mohr et al. [Phys. Rev. C 55, 1591 (1997)] for extracting the spectroscopic factor for a bound s-wave neutron state from the scattering length appears to be of doubtful validity and accuracy.

  18. Comparison of risk factors for cervical spine, head, serious, and fatal injury in rollover crashes.

    PubMed

    Funk, James R; Cormier, Joseph M; Manoogian, Sarah J

    2012-03-01

    Previous epidemiological studies of rollover crashes have focused primarily on serious and fatal injuries in general, while rollover crash testing has focused almost exclusively on cervical spine injury. The purpose of this study was to examine and compare the risk factors for cervical spine, head, serious, and fatal injury in real world rollover crashes. Rollover crashes from 1995-2008 in the National Automotive Sampling System-Crashworthiness Data System (NASS-CDS) were investigated. A large data set of 6015 raw cases (2.5 million weighted) was generated. Nonparametric univariate analyses, univariate logistic regression, and multivariate logistic regression were conducted. Complete or partial ejection, a lack of seatbelt use, a greater number of roof inversions, and older occupant age significantly increased the risk of all types of injuries studied (p<0.05). Far side seating position increased the risk of fatal, head, and cervical spine injury (p<0.05), but not serious injury in general. Higher BMI was associated with an increased risk of fatal, serious, and cervical spine injury (p<0.05), but not head injury. Greater roof crush was associated with a higher rate of fatal and cervical spine injury (p<0.05). Vehicle type, occupant height, and occupant gender had inconsistent and generally non-significant effects on injury. This study demonstrates both common and unique risk factors for different types of injuries in rollover crashes. PMID:22269486

  19. Factors Associated With External and Internal Lymphedema in Patients With Head-and-Neck Cancer

    SciTech Connect

    Deng Jie; Ridner, Sheila H.; Dietrich, Mary S.; Wells, Nancy; Wallston, Kenneth A.; Sinard, Robert J.; Cmelak, Anthony J.; Murphy, Barbara A.

    2012-11-01

    Purpose: The purpose of this study was to examine factors associated with the presence of secondary external and internal lymphedema in patients with head-and-neck cancer (HNC). Methods and Materials: The sample included 81 patients {>=}3 months after HNC treatment. Physical and endoscopic examinations were conducted to determine if participants had external, internal, and/or combined head-and-neck lymphedema. Logistic regression analysis was used to examine the factors associated with the presence of lymphedema. Results: The following factors were statistically significantly associated with presence of lymphedema: (1) location of tumor associated with presence of external (P=.009) and combined lymphedema (P=.032); (2) time since end of HNC treatment associated with presence of external (P=.004) and combined lymphedema (P=.005); (3) total dosage of radiation therapy (P=.010) and days of radiation (P=.017) associated with the presence of combined lymphedema; (4) radiation status of surgical bed was associated with the presence of internal lymphedema, including surgery with postoperative radiation (P=.030) and (salvage) surgery in the irradiated field (P=.008); and (5) number of treatment modalities associated with external (P=.002), internal (P=.039), and combined lymphedema (P=.004). No demographic, health behavior-related, or comorbidity factors were associated with the presence of lymphedema in the sample. Conclusions: Select tumor and treatment parameters are associated with increased occurrence of lymphedema in patients with HNC. Larger and longitudinal studies are needed to identify adjusted effects and causative risk factors contributing to the development of lymphedema in patients with HNC.

  20. Scattering coefficients and gray-body factor for 1D BEC acoustic black holes: Exact results

    NASA Astrophysics Data System (ADS)

    Fabbri, Alessandro; Balbinot, Roberto; Anderson, Paul R.

    2016-03-01

    A complete set of exact analytic solutions to the mode equation is found in the region exterior to the acoustic horizon for a class of 1D Bose-Einstein condensate acoustic black holes. From these, analytic expressions for the scattering coefficients and gray-body factor are obtained. The results are used to verify previous predictions regarding the behaviors of the scattering coefficients and gray-body factor in the low-frequency limit.

  1. Influence of length and conformation of saccharide head groups on the mechanics of glycolipid membranes: Unraveled by off-specular neutron scattering.

    PubMed

    Yamamoto, Akihisa; Abuillan, Wasim; Burk, Alexandra S; Körner, Alexander; Ries, Annika; Werz, Daniel B; Demé, Bruno; Tanaka, Motomu

    2015-04-21

    The mechanical properties of multilayer stacks of Gb3 glycolipid that play key roles in metabolic disorders (Fabry disease) were determined quantitatively by using specular and off-specular neutron scattering. Because of the geometry of membrane stacks deposited on planar substrates, the scattered intensity profile was analyzed in a 2D reciprocal space map as a function of in-plane and out-of-plane scattering vector components. The two principal mechanical parameters of the membranes, namely, bending rigidity and compression modulus, can be quantified by full calculation of scattering functions with the aid of an effective cut-off radius that takes the finite sample size into consideration. The bulkier "bent" Gb3 trisaccharide group makes the membrane mechanics distinctly different from cylindrical disaccharide (lactose) head groups and shorter "bent" disaccharide (gentiobiose) head groups. The mechanical characterization of membranes enriched with complex glycolipids has high importance in understanding the mechanisms of diseases such as sphingolipidoses caused by the accumulation of non-degenerated glycosphingolipids in lysosomes or inhibition of protein synthesis triggered by the specific binding of Shiga toxin to Gb3. PMID:25903910

  2. Influence of length and conformation of saccharide head groups on the mechanics of glycolipid membranes: Unraveled by off-specular neutron scattering

    SciTech Connect

    Yamamoto, Akihisa E-mail: tanaka@uni-heidelberg.de; Tanaka, Motomu E-mail: tanaka@uni-heidelberg.de; Abuillan, Wasim; Körner, Alexander; Burk, Alexandra S.; Ries, Annika; Werz, Daniel B.; Demé, Bruno

    2015-04-21

    The mechanical properties of multilayer stacks of Gb3 glycolipid that play key roles in metabolic disorders (Fabry disease) were determined quantitatively by using specular and off-specular neutron scattering. Because of the geometry of membrane stacks deposited on planar substrates, the scattered intensity profile was analyzed in a 2D reciprocal space map as a function of in-plane and out-of-plane scattering vector components. The two principal mechanical parameters of the membranes, namely, bending rigidity and compression modulus, can be quantified by full calculation of scattering functions with the aid of an effective cut-off radius that takes the finite sample size into consideration. The bulkier “bent” Gb3 trisaccharide group makes the membrane mechanics distinctly different from cylindrical disaccharide (lactose) head groups and shorter “bent” disaccharide (gentiobiose) head groups. The mechanical characterization of membranes enriched with complex glycolipids has high importance in understanding the mechanisms of diseases such as sphingolipidoses caused by the accumulation of non-degenerated glycosphingolipids in lysosomes or inhibition of protein synthesis triggered by the specific binding of Shiga toxin to Gb3.

  3. Influence of length and conformation of saccharide head groups on the mechanics of glycolipid membranes: Unraveled by off-specular neutron scattering

    NASA Astrophysics Data System (ADS)

    Yamamoto, Akihisa; Abuillan, Wasim; Burk, Alexandra S.; Körner, Alexander; Ries, Annika; Werz, Daniel B.; Demé, Bruno; Tanaka, Motomu

    2015-04-01

    The mechanical properties of multilayer stacks of Gb3 glycolipid that play key roles in metabolic disorders (Fabry disease) were determined quantitatively by using specular and off-specular neutron scattering. Because of the geometry of membrane stacks deposited on planar substrates, the scattered intensity profile was analyzed in a 2D reciprocal space map as a function of in-plane and out-of-plane scattering vector components. The two principal mechanical parameters of the membranes, namely, bending rigidity and compression modulus, can be quantified by full calculation of scattering functions with the aid of an effective cut-off radius that takes the finite sample size into consideration. The bulkier "bent" Gb3 trisaccharide group makes the membrane mechanics distinctly different from cylindrical disaccharide (lactose) head groups and shorter "bent" disaccharide (gentiobiose) head groups. The mechanical characterization of membranes enriched with complex glycolipids has high importance in understanding the mechanisms of diseases such as sphingolipidoses caused by the accumulation of non-degenerated glycosphingolipids in lysosomes or inhibition of protein synthesis triggered by the specific binding of Shiga toxin to Gb3.

  4. Vehicle Related Factors that Influence Injury Outcome in Head-On Collisions

    PubMed Central

    Blum, Jeremy J.; Scullion, Paul; Morgan, Richard M.; Digges, Kennerly; Kan, Cing-Dao; Park, Shinhee; Bae, Hanil

    2008-01-01

    This study specifically investigated a range of vehicle-related factors that are associated with a lower risk of serious or fatal injury to a belted driver in a head-on collision. This analysis investigated a range of structural characteristics, quantities that describes the physical features of a passenger vehicle, e.g., stiffness or frontal geometry. The study used a data-mining approach (classification tree algorithm) to find the most significant relationships between injury outcome and the structural variables. The algorithm was applied to 120,000 real-world, head-on collisions, from the National Highway Traffic Safety Administration’s (NHTSA’s) State Crash data files, that were linked to structural attributes derived from frontal crash tests performed as part of the USA New Car Assessment Program. As with previous literature, the analysis found that the heavier vehicles were correlated with lower injury risk to their drivers. This analysis also found a new and significant correlation between the vehicle’s stiffness and injury risk. When an airbag deployed, the vehicle’s stiffness has the most statistically significant correlation with injury risk. These results suggest that in severe collisions, lower intrusion in the occupant cabin associated with higher stiffness is at least as important to occupant protection as vehicle weight for self-protection of the occupant. Consequently, the safety community might better improve self-protection by a renewed focus on increasing vehicle stiffness in order to improve crashworthiness in head-on collisions. PMID:19026230

  5. Head and Neck Cancer Pain: Systematic Review of Prevalence and Associated Factors

    PubMed Central

    Wirth, Tanja; Ranasinghe, Sriyani; Ah-See, Kim W.; Renny, Nick; Hurman, David

    2012-01-01

    ABSTRACT Objectives Pain is a major symptom in patients with cancer; however information on head and neck cancer related pain is limited. The aim of this review was to investigate the prevalence of pain and associated factors among patients with HNC. Material and Methods The systematic review used search of MEDLINE, EMBASE and CINAHL databases to December 2011. Cancers of the oral mucosa, oropharynx, hypopharynx and larynx were included in this review with pain as main outcome. The review was restricted to full research reports of observational studies published in English. A checklist was used to assess the quality of selected studies. Results There were 82 studies included in the review and most of them (84%) were conducted in the past ten years. Studies were relatively small, with a median of 80 patients (IQR 44, 154). The quality of reporting was variable. Most studies (77%) used self-administered quality of life questionnaires, where pain was a component of the overall scale. Only 33 studies reported pain prevalence in HNC patients (combined estimate from meta-analysis before (57%, 95% CI 43% - 70%) and after (42%, 95% CI 33% - 50%) treatment. Only 49 studies (60%) considered associated factors, mostly tumour- or treatment-related. Conclusions The study has shown high levels of pain prevalence and some factors associated with higher levels of pain. There is a need for higher quality studies in a priority area for the care of patients with head and neck cancer. PMID:24422003

  6. Targeting epidermal growth factor receptor for head and neck squamous cell carcinoma: still lost in translation?

    PubMed Central

    Chapman, Christopher H.; Saba, Nabil F.

    2016-01-01

    The epidermal growth factor receptor (EGFR) is preferentially expressed in head and neck squamous cell carcinoma (HNSCC), and is a promising therapeutic target. Yet other than cetuximab, no agent targeting EGFR has been approved for this disease, and none has shown benefit over the standard of care. Several randomized trials of antibody and small molecule agents have found no new indication for these agents, despite their initial promise. In this review, we examine the major clinical evidence and discuss potential future developments of translational science in this area, including use of these agents in risk-stratified subgroups, inhibition of downstream/parallel targets, and combination with immunotherapy. PMID:27004227

  7. The Proton Coulomb Form Factor from Polarized Inclusive e-p Scattering

    SciTech Connect

    Chris Harris

    2001-08-01

    The proton form factors provide information on the fundamental properties of the proton and provide a test for models based on QCD. In 1998 at Jefferson Lab (JLAB) in Newport News, VA, experiment E93026 measured the inclusive e-p scattering cross section from a polarized ammonia (15NH3) target at a four momentum transfer squared of Q2 = 0.5 (GeV/c)2. Longitudinally polarized electrons were scattered from the polarized target and the scattered electron was detected. Data has been analyzed to obtain the asymmetry from elastically scattered electrons from hydrogen in 15NH3. The asymmetry, Ap, has been used to determine the proton elastic form factor GEp. The result is consistent with the dipole model and data from previous experiments. However, due to the choice of kinematics, the uncertainty in the measurement is large.

  8. Measurement of the neutron electric form factor GEn in quasielastic scattering

    SciTech Connect

    Donal Day

    2003-07-15

    We have measured the electric form factor of the neutron, GEn, at two momentum transfers (Q2= 0.5 and Q2= 1.0 GeV/c2) through quasielastic scattering in Jefferson Lab's Hall C. Longitudinally polarized electrons scattered from polarized deuterated ammonia and GEn was extracted from the beam-target asymmetry AVed which, in quasielastic kinematics, is particularly sensitive to GEn and insensitive to MEC and FSI.

  9. Towards the estimation of the scattered energy spectra reaching the head of the medical staff during interventional radiology: A Monte Carlo simulation study

    NASA Astrophysics Data System (ADS)

    Zagorska, A.; Bliznakova, K.; Buchakliev, Z.

    2015-09-01

    In 2012, the International Commission on Radiological Protection has recommended a reduction of the dose limits to the eye lens for occupational exposure. Recent studies showed that in interventional rooms is possible to reach these limits especially without using protective equipment. The aim of this study was to calculate the scattered energy spectra distribution at the level of the operator's head. For this purpose, an in-house developed Monte Carlo-based computer application was used to design computational phantoms (patient and operator), the acquisition geometry as well as to simulate the photon transport through the designed system. The initial spectra from 70 kV tube voltage and 8 different filtrations were calculated according to the IPEM Report 78. An experimental study was carried out to verify the results from the simulations. The calculated scattered radiation distributions were compared to the initial incident on the patient spectra. Results showed that there is no large difference between the effective energies of the scattered spectra registered in front of the operator's head obtained from simulations of all 8 incident spectra. The results from the experimental study agreed well to simulations as well.

  10. Dysregulation of epidermal growth factor receptor expression in premalignant lesions during head and neck tumorigenesis.

    PubMed

    Shin, D M; Ro, J Y; Hong, W K; Hittelman, W N

    1994-06-15

    The development of head and neck cancer, believed to result from field cancerization and a multistep process of tumorigenesis, is often associated with an accumulation of genotypic and phenotypic alterations. The phenotypic changes could be the result of dysregulation of growth control genes such as epidermal growth factor receptor (EGFR). With the goal of identifying a potential biomarker of the multistep process of tumorigensis, we studied specimens of 36 head and neck squamous cell carcinomas from 5 different sites that contained normal epithelia and/or premalignant lesions adjacent to the tumors. Almost all of the individuals from whom these specimens were obtained had been exposed to first-hand smoking and/or alcohol consumption. Using a monoclonal anti-EGFR antibody for immunohistochemical analysis on paraffin-embedded sections with attached 886 cells for internal control, the levels of EGFR expression were assessed by image analysis. The relative staining intensity of EGFR in normal epithelia adjacent to tumors was 2-fold higher than that in normal control epithelium (P = 0.021), suggesting that, even in histologically normal epithelium, EGFR was already up-regulated in tissues surrounding tumors. These findings supported the theory of field cancerization in head and neck tumorigenesis. As tissue progressed from normal tissue adjacent to tumor to hyperplasia and to dysplasia, EGFR expression remained elevated. However, in the step from dysplasia to squamous cell carcinoma, EGFR expression was further and dramatically up-regulated (P = 0.01). Therefore, these results indicate that EGFR dysregulation happens in two steps, the moderate up-regulation of EGFR expression in normal epithelium adjacent to tumor and the further up-regulation of EGFR expression in the change from dysplasia to squamous cell carcinoma. In summary, the studies presented here indicate that EGFR dysregulation might be a useful marker for identifying individuals at risk of tumor development

  11. Risk factors of recipient site infection in head and neck cancer patients undergoing pectoralis major myocutaneous flap reconstruction.

    PubMed

    Wang, Chao-Hsien; Wong, Yong-Kie; Wang, Ching-Ping; Wang, Chen-Chi; Jiang, Rong-San; Lai, Chih-Sheng; Liu, Shih-An

    2015-11-01

    The aim of this study was to investigate the factors associated with infection at the recipient site of pectoralis major myocutaneous flap (PMMF) of head and neck cancer patients. We retrospectively reviewed head and neck cancer patients who underwent PMMF reconstruction and identified those with recipient site infection. Variables of patients with and without infection were compared and associated factors were investigated by logistic regression model. A total of 478 patients were included in the final analysis and 183 patients (38.3%) developed recipient site infection. Lower margin of skin island, concurrent tracheotomy, diabetes mellitus, mandibular plate reconstruction, prior radiation, and peri-operative blood transfusion were independent factors associated with recipient site infection of PMMF. Skin island of PMMF beyond the eighth intercostal space markedly increased the risk of recipient site infection after major head and neck cancer surgery. Recognition of relevant factors associated with infection may help surgeons to identify those at risk. PMID:25359197

  12. The Risk Factors for Hydrocephalus and Subdural Hygroma after Decompressive Craniectomy in Head Injured Patients

    PubMed Central

    Ki, Hee Jong; Lee, Hong-Jae; Yi, Jin-Seok; Yang, Ji-Ho; Lee, Il-Woo

    2015-01-01

    Objective The present study aims to investigate 1) the risk factors for hydrocephalus and subdural hygroma (SDG) occurring after decompressive craniectomy (DC), and 2) the association between the type of SDG and hydrocephalus. Methods We retrospectively reviewed the clinical and radiological features of 92 patients who underwent DC procedures after severe head injuries. The risk factors for developing post-traumatic hydrocephalus (PTH) and SDG were analyzed. Types of SDGs were classified according to location and their relationship with hydrocephalus was investigated. Results Ultimately, 26.09% (24/92) of these patients developed PTH. In the univariate analyses, hydrocephalus was statically associated with large bone flap diameter, large craniectomy area, bilateral craniectomy, intraventricular hemorrhage, contralateral or interhemisheric SDGs, and delayed cranioplasty. However, in the multivariate analysis, only large craniectomy area (adjusted OR=4.66; p=0.0239) and contralateral SDG (adjusted OR=6.62; p=0.0105) were significant independent risk factors for developing hydrocephalus after DC. The incidence of overall SDGs after DC was 55.43% (51/92). Subgroup analysis results were separated by SDG types. Statistically significant associations between hydrocephalus were found in multivariate analysis in the contralateral (adjusted OR=5.58; p=0.0074) and interhemispheric (adjusted OR=17.63; p=0.0113) types. Conclusion For patients who are subjected to DC following severe head trauma, hydrocephalus is associated with a large craniectomy area and contralateral SDG. For SDGs after DC that occur on the interhemispherical or controlateral side of the craniectomy, careful follow-up monitoring for the potential progression into hydrocephalus is needed. PMID:26539270

  13. In-vivo Optical Tomography of Small Scattering Specimens: time-lapse 3D imaging of the head eversion process in Drosophila melanogaster

    PubMed Central

    Arranz, Alicia; Dong, Di; Zhu, Shouping; Savakis, Charalambos; Tian, Jie; Ripoll, Jorge

    2014-01-01

    Even though in vivo imaging approaches have witnessed several new and important developments, specimens that exhibit high light scattering properties such as Drosophila melanogaster pupae are still not easily accessible with current optical imaging techniques, obtaining images only from subsurface features. This means that in order to obtain 3D volumetric information these specimens need to be studied either after fixation and a chemical clearing process, through an imaging window - thus perturbing physiological development -, or during early stages of development when the scattering contribution is negligible. In this paper we showcase how Optical Projection Tomography may be used to obtain volumetric images of the head eversion process in vivo in Drosophila melanogaster pupae, both in control and headless mutant specimens. Additionally, we demonstrate the use of Helical Optical Projection Tomography (hOPT) as a tool for high throughput 4D-imaging of several specimens simultaneously. PMID:25471694

  14. In-vivo optical tomography of small scattering specimens: time-lapse 3D imaging of the head eversion process in Drosophila melanogaster.

    PubMed

    Arranz, Alicia; Dong, Di; Zhu, Shouping; Savakis, Charalambos; Tian, Jie; Ripoll, Jorge

    2014-01-01

    Even though in vivo imaging approaches have witnessed several new and important developments, specimens that exhibit high light scattering properties such as Drosophila melanogaster pupae are still not easily accessible with current optical imaging techniques, obtaining images only from subsurface features. This means that in order to obtain 3D volumetric information these specimens need to be studied either after fixation and a chemical clearing process, through an imaging window--thus perturbing physiological development -, or during early stages of development when the scattering contribution is negligible. In this paper we showcase how Optical Projection Tomography may be used to obtain volumetric images of the head eversion process in vivo in Drosophila melanogaster pupae, both in control and headless mutant specimens. Additionally, we demonstrate the use of Helical Optical Projection Tomography (hOPT) as a tool for high throughput 4D-imaging of several specimens simultaneously. PMID:25471694

  15. Factors that affect response to chemotherapy and survival of patients with advanced head and neck cancer.

    PubMed

    Amer, M H; Al-Sarraf, M; Vaitkevicius, V K

    1979-06-01

    A review of 164 patients with far advanced head and neck cancer, treated by a cytotoxic chemotherapy over a ten year period, at WAyne State University, Detroit, Michigan, was done in an attempt to determine factors that may influence the response to chemotherapy and subsequent survival. Response rate to methotrexate was 28%, 5-FU 31%, and porfiromycin 13%. Improved responses were noted with combination chemotherapy. Patients who failed to first line therapy rarely responded to other single agent or combination chemotherapy. Those who did not have prior surgery and/or radiotherapy had better results from drug therapy. Patients with good performance status at the time of initial chemotherapy, had better response to treatment (32% vs. 13% PR & CR) and longer survival (28 weeks vs. 9 weeks, p = 0.01) when compared to those with poor status. Patients who responded to chemotherapy have better survival compared to nonresponders (29 weeks vs. 16 weeks, p = 0.002). This information may prove helpful in future planning of multidisciplinary approach in the treatment of patients with head and neck cancer. PMID:455217

  16. Foam dressing with epidermal growth factor for severe radiation dermatitis in head and neck cancer patients.

    PubMed

    Lee, Jihyo; Lee, Sang-Wook; Hong, Joon Pio; Shon, Myeong Wha; Ryu, Seung-Hee; Ahn, Seung Do

    2016-06-01

    This study was conducted to evaluate the effects of foam dressing with human recombinant human epidermal growth factor (rhEGF) on the healing process in head and neck cancer patients who experience radiation-induced dermatitis (RID). Seven patients, including three with oropharyngeal, two with nasopharyngeal and one each with hypopharyngeal and laryngeal carcinoma, who underwent radiotherapy (RT) for head and neck cancer at the Asan Medical Center from March to December 2008 were prospectively included in this study. Patients who showed severe RID (more than wet desquamation) on the supraclavicular fossa or neck areas were treated by wound cleaning and debridement of granulation tissue, followed by daily rhEGF spray and foam dressing. Median time to stop exudates and reepithelialisation was 4 days. Within 14 days (median 8 days), all patients showed complete healing of RID and no longer required dressings. This new method of treatment with dressing containing rhEGF may have the potential to accelerate the healing process in patients with RID. A case-control study is needed to confirm this finding. PMID:24947011

  17. An analytical formalism to calculate phantom scatter factors for flattening filter free (FFF) mode photon beams

    NASA Astrophysics Data System (ADS)

    Chung, Heeteak; Prado, Karl L.; Yi, Byong Yong

    2014-02-01

    Phantom Scatter Factors, Sp in the Khan formalism (Khan et al 1980 J. Radiat. Oncol. Biol. Phys. 6 745-51) describe medium-induced changes in photon-beam intensity as a function of size of the beam. According to the British Journal of Radiology, Supplement 25, megavoltage phantom scatter factors are invariant as a function of photon-beam energy. However, during the commissioning of an accelerator with flattening filter free (FFF) photon beams (Varian TrueBeamTM 6-MV FFF and 10-MV FFF), differences were noted in phantom scatter between the filtered beams and FFF-mode beams. The purpose of this work was to evaluate this difference and provide an analytical formalism to explain the phantom scatter differences between FFF-mode and the filtered mode. An analytical formalism was devised to demonstrate the source of phantom scatter differences between the filtered and the FFF-mode beams. The reason for the differences in the phantom scatter factors between the filtered and the FFF-mode beams is hypothesized to be the non-uniform beam profiles of the FFF-mode beams. The analytical formalism proposed here is based on this idea, taking the product of the filtered phantom scatter factors and the ratio of the off-axis ratio between the FFF-mode and the filtered beams. All measurements were performed using a Varian TrueBeamTM linear accelerator with photon energies of 6-MV and 10-MV in both filtered and FFF-modes. For all measurements, a PTW Farmer type chamber and a Scanditronix CC04 cylindrical ionization were used. The in-water measurements were made at depth dose maximum and 100 cm source-to-axis distance. The in-air measurements were done at 100 cm source-to-axis distance with appropriate build-up cap. From these measurements, the phantom scatter factors were derived for the filtered beams and the FFF-mode beams for both energies to be evaluated against the phantoms scatter factors calculated using the proposed algorithm. For 6-MV, the difference between the measured and

  18. An analytical formalism to calculate phantom scatter factors for flattening filter free (FFF) mode photon beams.

    PubMed

    Chung, Heeteak; Prado, Karl L; Yi, Byong Yong

    2014-02-21

    Phantom Scatter Factors, Sp in the Khan formalism (Khan et al 1980 J. Radiat. Oncol. Biol. Phys. 6 745-51) describe medium-induced changes in photon-beam intensity as a function of size of the beam. According to the British Journal of Radiology, Supplement 25, megavoltage phantom scatter factors are invariant as a function of photon-beam energy. However, during the commissioning of an accelerator with flattening filter free (FFF) photon beams (Varian TrueBeam(TM) 6-MV FFF and 10-MV FFF), differences were noted in phantom scatter between the filtered beams and FFF-mode beams. The purpose of this work was to evaluate this difference and provide an analytical formalism to explain the phantom scatter differences between FFF-mode and the filtered mode. An analytical formalism was devised to demonstrate the source of phantom scatter differences between the filtered and the FFF-mode beams. The reason for the differences in the phantom scatter factors between the filtered and the FFF-mode beams is hypothesized to be the non-uniform beam profiles of the FFF-mode beams. The analytical formalism proposed here is based on this idea, taking the product of the filtered phantom scatter factors and the ratio of the off-axis ratio between the FFF-mode and the filtered beams. All measurements were performed using a Varian TrueBeam(TM) linear accelerator with photon energies of 6-MV and 10-MV in both filtered and FFF-modes. For all measurements, a PTW Farmer type chamber and a Scanditronix CC04 cylindrical ionization were used. The in-water measurements were made at depth dose maximum and 100 cm source-to-axis distance. The in-air measurements were done at 100 cm source-to-axis distance with appropriate build-up cap. From these measurements, the phantom scatter factors were derived for the filtered beams and the FFF-mode beams for both energies to be evaluated against the phantoms scatter factors calculated using the proposed algorithm. For 6-MV, the difference between the measured

  19. Head-up displays and their automotive application: an overview of human factors issues affecting safety.

    PubMed

    Ward, N J; Parkes, A

    1994-12-01

    In response to the recent innovations to use head-up displays (HUDs) in vehicles, this paper discusses the relevant human factors issues arising from this display format and the potential safety implications. A review is made of the relevant HUD literature, primarily from the aviation field. The primary issues for automotive HUDs relevant to system performance and safety in the driving task involve interference from background scene complexity, system novelty, user perceptual style, cognitive disruption, and perceptual tunnelling. Basic research is necessary to investigate the extent of these issues as well as to resolve fundamental design specifications (e.g. HUD size, shape, placement, information content). It is suggested that the introduction of HUDs into vehicles be carefully considered. This will necessitate not only the reconsideration what constitutes an in-vehicle display, but also what constitutes the information to be conveyed. PMID:7857487

  20. Scattering from phase-separated vesicles. I. An analytical form factor for multiple static domains

    DOE PAGESBeta

    Heberle, Frederick A.; Anghel, Vinicius N. P.; Katsaras, John

    2015-08-18

    This is the first in a series of studies considering elastic scattering from laterally heterogeneous lipid vesicles containing multiple domains. Unique among biophysical tools, small-angle neutron scattering can in principle give detailed information about the size, shape and spatial arrangement of domains. A general theory for scattering from laterally heterogeneous vesicles is presented, and the analytical form factor for static domains with arbitrary spatial configuration is derived, including a simplification for uniformly sized round domains. The validity of the model, including series truncation effects, is assessed by comparison with simulated data obtained from a Monte Carlo method. Several aspects ofmore » the analytical solution for scattering intensity are discussed in the context of small-angle neutron scattering data, including the effect of varying domain size and number, as well as solvent contrast. Finally, the analysis indicates that effects of domain formation are most pronounced when the vesicle's average scattering length density matches that of the surrounding solvent.« less

  1. Accurate measurement of the x-ray coherent scattering form factors of tissues

    NASA Astrophysics Data System (ADS)

    King, Brian W.

    The material dependent x-ray scattering properties of tissues are determined by their scattering form factors, measured as a function of the momentum transfer argument, x. Incoherent scattering form factors, Finc, are calculable for all values of x while coherent scattering form factors, Fcoh, cannot be calculated except at large C because of their dependence on long range order. As a result, measuring Fcoh is very important to the developing field of x-ray scatter imaging. Previous measurements of Fcoh, based on crystallographic techniques, have shown significant variability, as these methods are not optimal for amorphous materials. Two methods of measuring F coh, designed with amorphous materials in mind, are developed in this thesis. An angle-dispersive technique is developed that uses a polychromatic x-ray beam and a large area, energy-insensitive detector. It is shown that Fcoh can be measured in this system if the incident x-ray spectrum is known. The problem is ill-conditioned for typical x-ray spectra and two numerical methods of dealing with the poor conditioning are explored. It is shown that these techniques work best with K-edge filters to limit the spectral width and that the accuracy degrades for strongly ordered materials. Measurements of width Fcoh for water samples are made using 50, 70 and 92 kVp spectra. The average absolute relative difference in Fcoh between our results and the literature for water is approximately 10-15%. Similar measurements for fat samples were made and found to be qualitatively similar to results in the literature, although there is very large variation between the literature values in this case. The angle-dispersive measurement is limited to low resolution measurements of the coherent scattering form factor although it is more accessible than traditional measurements because of the relatively commonplace equipment requirements. An energy-dispersive technique is also developed that uses a polychromatic x-ray beam and an

  2. Determination of scatter factor parameters and electron disequilibrium for monoenergetic photon beams.

    PubMed

    McDonough, J; Bloch, P; Bjärngard, B E

    1999-02-01

    The tissue-phantom-ratio (TPR) is expressed as the product of the phantom scatter factor (SF), an electron disequilibrium factor, and an attenuation factor, equal to the zero-area TPR. The scatter factor, as a function of depth d and field size s, has been described by two parameters a and w, SF(d,s) = 1 + asd/(ws + d). We have determined the parameters a and w for 20 monoenergetic photon beams between 1 and 20 MeV. Pencil-beam energy-deposition kernels were obtained using Monte Carlo simulations. The kernels were used to calculate broad-beam depth-dose data, which were converted to TPR and fitted to the equation above using an iterative search over a-w space. The parameter a is nearly equal to the attenuation coefficient for all energies while the parameter w increases with energy. The resulting a and w compare favorably to values determined for clinical photon beams, as a function of the measured attenuation coefficient. With the scatter factor determined, we isolated the electron disequilibrium factor for each monoenergetic beam. It can be characterized as a quadratic function of the depth. The coefficients of the quadratic function can be related to the range of the most energetic secondary electron produced. PMID:10076974

  3. Bidirectional scattering distribution function measurements from volume diffusers: correction factors and associated uncertainties.

    PubMed

    Germer, Thomas A

    2016-09-01

    We consider the effect of volume diffusion on measurements of the bidirectional scattering distribution function when a finite distance is used for the solid angle defining aperture. We derive expressions for correction factors that can be used when the reduced scattering coefficients and the index of refraction are known. When these quantities are not known, the expressions can be used to guide the assessment of measurement uncertainty. We find that some measurement geometries reduce the effect of volume diffusion compared to their reciprocal geometries. PMID:27607273

  4. Stepwise Progress in Epidermal Growth Factor Receptor/Radiation Studies for Head and Neck Cancer

    SciTech Connect

    Harari, Paul M.

    2007-10-01

    The U.S. Food and Drug Administration approval of four new epidermal growth factor receptor (EGFR) inhibitors for cancer therapy (cetuximab, panitumumab, gefitinib, and erlotinib) over the last 3 years is a remarkable milestone in oncology. Indeed, molecular inhibition of EGFR signaling represents one of the most promising current arenas for the development of molecular-targeted cancer therapies. Epidermal growth factor receptor inhibitors from both the monoclonal antibody and tyrosine kinase inhibitor class have demonstrated clinical activity in the treatment of a broad spectrum of common human malignancies. For the discipline of radiation oncology, the 2006 report of a phase III trial demonstrating a survival advantage for advanced head and neck cancer patients with the addition of weekly cetuximab during a 7-week course of radiation is particularly gratifying. Indeed, this is the first phase III trial to confirm a survival advantage with the addition of a molecular-targeted agent to radiation. Furthermore, this result seems to have been achieved with only a modest increment in overall treatment toxicity and with very high compliance to the prescribed treatment regimen. Nevertheless, much remains to be learned regarding the rational integration of EGFR inhibitors into cancer treatment regimens, as well as methods to optimize the selection of patients most likely to benefit from EGFR inhibitor strategies.

  5. Risk factors associated with retinal hemorrhage in suspected abusive head trauma

    PubMed Central

    Burkhart, Zachary N.; Thurber, Clinton J.; Chuang, Alice Z.; Kumar, Kartik S.; Davis, Garvin H.; Kellaway, Judianne

    2015-01-01

    Purpose To determine risk factors associated with retinal hemorrhage (RH) in pediatric abusive head trauma (AHT) suspects. Methods Records of children aged 0–3 years hospitalized for suspected AHT from January 2007 to November 2011 were retrospectively reviewed in this case–control study. Children were classified into case and control groups based on RH presence. Medical history, presenting symptoms, reasons, and characteristics of injury were recorded. Logistic regression analysis was performed to identify risk factors. Results A total of 168 children (104 males) were included. Of these, 103 were classified as cases and 65 as controls. The mean age (with standard deviation) was 9.3 ± 8.3 months (range, 1 day-36 months). Of the 103 cases, 22 (21%) had subretinal hemorrhage, 9 (9%) had retinoschisis, and 1 (1%) had vitreous hemorrhage. Children presenting with lethargy or altered mental status (P < 0.0001), subdural hemorrhage (P < 0.0001), and other radiologic findings (eg, cerebral ischemia, diffuse axonal injury, hydrocephalus, or solid organ injury; P = 0.01546) were likely to have RH. All 23 children with skull or nonskull fracture without intracranial hemorrhage did not have RH (P < 0.0001 both categories). Conclusions Retinal hemorrhages were almost never found in the absence of intracranial hemorrhage and not found in the setting of fracture without intracranial hemorrhage. PMID:25828822

  6. X-ray coherent scattering form factors of tissues, water and plastics using energy dispersion

    NASA Astrophysics Data System (ADS)

    King, B. W.; Landheer, K. A.; Johns, P. C.

    2011-07-01

    A key requirement for the development of the field of medical x-ray scatter imaging is accurate characterization of the differential scattering cross sections of tissues and phantom materials. The coherent x-ray scattering form factors of five tissues (fat, muscle, liver, kidney, and bone) obtained from butcher shops, four plastics (polyethylene, polystyrene, lexan (polycarbonate), nylon), and water have been measured using an energy-dispersive technique. The energy-dispersive technique has several improvements over traditional diffractometer measurements. Most notably, the form factor is measured on an absolute scale with no need for scaling factors. Form factors are reported in terms of the quantity x = λ-1sin (θ/2) over the range 0.363-9.25 nm-1. The coherent form factors of muscle, liver, and kidney resemble those of water, while fat has a narrower peak at lower x, and bone is more structured. The linear attenuation coefficients of the ten materials have also been measured over the range 30-110 keV and parameterized using the dual-material approach with the basis functions being the linear attenuation coefficients of polymethylmethacrylate and aluminum.

  7. Parity-Violating Electron Scattering and the Electric and Magnetic Strange Form Factors of the Nucleon

    SciTech Connect

    Armstrong, David S.; McKeown, Robert

    2012-11-01

    Measurement of the neutral weak vector form factors of the nucleon provides unique access to the strange quark content of the nucleon. These form factors can be studied using parity-violating electron scattering. A comprehensive program of experiments has been performed at three accelerator laboratories to determine the role of strange quarks in the electromagnetic form factors of the nucleon. This article reviews the remarkable technical progress associated with this program, describes the various methods used in the different experiments, and summarizes the physics results along with recent theoretical calculations.

  8. Calculation of inelastic electron-nucleus scattering form factors of 29Si

    NASA Astrophysics Data System (ADS)

    Salman, A. D.; Al-Dahan, N.; Sharrad, F. I.; Hossain, I.

    2014-08-01

    Inelastic electron scattering form factors for 29Si nucleus with total angular momentum and positive parity (Jπ) and excited energy (3/2+, 1.273 MeV; 5/2+, 2.028 MeV; 3/2+, 2.425 MeV and 7/2+, 4.079 MeV) have been calculated using higher energy configurations outside the sd-shell. The calculations of inelastic form factors up to the first- and second-order with and without core-polarization (CP) effects were compared with the available experimental data. The calculations of inelastic electron scattering form factors up to the first-order with CP effects are in agreement with the experimental data, excepted for states 3/2+(1.273 MeV) and 5/2+(2.028 MeV) and without this effect are failed for all states. Furthermore, the calculations of inelastic electron scattering form factors up to the second-order with CP effects are in agreement with the experimental data for 3/2+(1.273 MeV) and 5/2+(2.028 MeV).

  9. Risk factors for chronic subdural hematoma after a minor head injury in the elderly: a population-based study.

    PubMed

    Tseng, Jen-Ho; Tseng, Ming-Yuan; Liu, Ann-Jeng; Lin, Wen-Hsiung; Hu, Hsiao-Yun; Hsiao, Sheng-Huang

    2014-01-01

    Chronic subdural hematoma (CSDH) is one of the major comorbidities in elderly resulting in disability and death. Early recognition of CSDH is important for early management. However, manifestations of CSDH are nonspecific and subtle. Therefore, identification of risk factors of CSDH can offer clinical follow-up strategies for patients after episodes of head injury. The purpose of the study aimed at identifying risk factors of CSDH of Taiwanese. Analysis of data from the National Health Insurance provides important information on predictive factors influencing the early diagnosis of CSDH in elderly patients following minor head injuries. The current study is the first nationwide population-based study in Taiwan, showing that old age (≥75 years), male gender, and coexisting hydrocephalus are significantly predictive factors, irrespective to their medical comorbidities. PMID:25295251

  10. [Human papilloma viruses: other risk factor of head and neck carcinoma].

    PubMed

    Woto-Gaye, G; M'Farrej, M K; Doh, K; Thiam, I; Touré, S; Diop, R; Dial, C

    2016-08-01

    Head and neck carcinoma (HNC) occupy the sixth place as the most frequent type of cancer worldwide. Next to alcohol and tobacco intoxication, other risk factors (RF) are suspected, including the human papilloma viruses (HPVs). The aim of this study was to highlight the prevalence of HPVs and histo-epidemiological characteristics of HNC HPV+ in Senegal. This is a prospective, multicenter preliminary study of 18 months (January 1, 2012-June 30, 2014). The cases of HNC histologically confirmed in Senegal were then sent to the bio-pathology department of the Curie Institute in Paris to search HPVs. In the 90 included cases, the PCR technique was successful in 54 cases (60%). HPVs were found in seven cases, that is, a prevalence of 13%. HPVs were associated with 5 cases of hypopharyngeal carcinoma and 2 cases of carcinoma of the oral cavity. Patients with HNC HPV+ had a median age of 42 years against 49 years for HPV-patients. Three patients (42.8%) with HPV+ carcinomas were smokers. Of the 47 HPV-patients, 40 patients (87.1%) had alcohol intoxication and/or smoking. The concept of oral sex was refuted by all our patients. Squamous cell carcinoma was the only histological type found. HPV+ cell carcinoma showed no specific histological appearance. HPVs are another certain RF of HNC in Senegal. The major therapeutic and prognostic impact of HPVinduced cancers requires the systematic search of the viruses by the PCR technique. PMID:27325173

  11. Test of factorization in diffractive deep inelastic scattering and photoproduction at HERA

    SciTech Connect

    Polifka, Richard

    2015-04-10

    The QCD factorization theorem in diffraction is tested by comparing diffractive jet production data to QCD predictions based on fits to inclusive diffractive cross section data. H1 measured dijet production with a leading proton detected in the Very Forward Proton Spectrometer (VFPS), both in deep-inelastic scattering and in photoproduction. The DIS measurements are complemented by measurements of dijet production with an associated rapidity gap and in a data sample selected with a leading proton in the Forward Proton Spectrometer (FPS)

  12. Is MDM2 SNP309 Variation a Risk Factor for Head and Neck Carcinoma?

    PubMed Central

    Zhuo, Xianlu; Ye, Huiping; Li, Qi; Xiang, Zhaolan; Zhang, Xueyuan

    2016-01-01

    Abstract Murine double minute-2 (MDM2) is a negative regulator of P53, and its T309G polymorphism has been suggested as a risk factor for a variety of cancers. Increasing evidence has shown the association of MDM2 T309G polymorphism with head and neck carcinoma (HNC) risk. However, the results are inconsistent. Thus, we performed a meta-analysis to elucidate the association. The meta-analysis retrieved studies published up to August 2015, and essential information was extracted for analysis. Separate analyses on ethnicity, source of controls, sample size, detection method, and cancer types were also conducted. Odds ratios (ORs) and their 95% confidence intervals (CIs) were used to estimate the association. Pooled data from 16 case–control studies including 4625 cases and 6927 controls failed to indicate a significant association. However, in the subgroup analysis of sample sizes, an increased risk was observed in the largest sample size group (>1000) under a recessive model (OR = 1.52; 95% CI = 1.08–2.13). Increased risks were also found in the nasopharyngeal cancer in the subgroup analysis of cancer types (GG vs TT: OR = 2.07; 95% CI = 1.38–3.12; dominant model: OR = 1.48; 95% CI = 1.13–1.93; recessive model: OR = 1.76; 95% CI = 1.17–2.65). The results suggest that homozygote GG alleles of MDM2 SNP309 may be a low-penetrant risk factor for HNC, and G allele may confer nasopharyngeal cancer susceptibility. PMID:26945408

  13. Head injuries in the female football player: incidence, mechanisms, risk factors and management

    PubMed Central

    Dvorak, Jiri; McCrory, Paul; Kirkendall, Donald T

    2007-01-01

    Although all injuries in sports are a concern for participants, head injuries are particularly troublesome because of the potential for long‐term cognitive deficits. To prevent any specific injury, it is important to understand the basic frequency and incidence of injury and then the mechanism of injury. Once these are established, prevention programmes can be tested to see if the rate of injury changes. A primary problem with head injuries is recognising that the injury has occurred. Many athletes are not aware of the seriousness of concussive injury, thus this type of injury is probably under‐reported. Once the diagnosis of a concussion is made, the next difficult decision is when to return a player to the game. These two management issues dominate the continuing development of understanding of concussive head injury. This paper explores the known gender differences between head injuries and highlights the areas that need to be considered in future research. PMID:17496069

  14. Tumor Necrosis Factor Inhibition and Head and Neck Cancer Recurrence and Death in Rheumatoid Arthritis

    PubMed Central

    Phillips, Christopher; Zeringue, Angelique L.; McDonald, Jay R.; Eisen, Seth A.; Ranganathan, Prabha

    2015-01-01

    The objective of this retrospective cohort study was to determine the effect of tumor necrosis factor inhibitor (TNFi) therapy on the risk of head and neck cancer (HNC) recurrence or HNC-attributable death in patients with rheumatoid arthritis (RA). RA patients with HNC were assembled from the US national Veterans’ Affairs (VA) administrative databases, and diagnoses confirmed and data collected by electronic medical record review. The cohort was divided into those treated with non-biologic disease-modifying anti-rheumatic drugs (nbDMARDs) versus TNF inhibitors (TNFi) after a diagnosis of HNC. Likelihood of a composite endpoint of recurrence or HNC-attributable death was determined by Cox proportional hazards regression. Of 180 patients with RA and HNC, 31 were treated with TNFi and 149 with nbDMARDs after the diagnosis of HNC. Recurrence or HNC-attributable death occurred in 5/31 (16.1%) patients in the TNFi group and 44/149 (29.5%) patients in the nbDMARD group (p = 0.17); it occurred in 2/16 (13%) patients who received TNFi in the year prior to HNC diagnosis but not after. Overall stage at diagnosis (p = 0.03) and stage 4 HNC (HR 2.49 [CI 1.06–5.89]; p = 0.04) were risk factors for recurrence or HNC-attributable death; treatment with radiation or surgery was associated with a lower risk (HR 0.35 [CI 0.17–0.74]; p = 0.01 and HR 0.39 [CI 0.20–0.76]; p = 0.01 respectively). Treatment with TNFi was not a risk factor for recurrence or HNC-attributable death (HR 0.75; CI 0.31–1.85; p = 0.54). We conclude that treatment with TNFi may be safe in patients with RA and HNC, especially as the time interval between HNC treatment and non-recurrence increases. In this study, TNF inhibition was not associated with an increase in recurrence or HNC-attributable death. PMID:26599370

  15. Towards a Resolution of the Proton Form Factor Problem: New Electron and Positron Scattering Data

    NASA Astrophysics Data System (ADS)

    Adikaram, D.; Rimal, D.; Weinstein, L. B.; Raue, B.; Khetarpal, P.; Bennett, R. P.; Arrington, J.; Brooks, W. K.; Adhikari, K. P.; Afanasev, A. V.; Amaryan, M. J.; Anderson, M. D.; Anefalos Pereira, S.; Avakian, H.; Ball, J.; Battaglieri, M.; Bedlinskiy, I.; Biselli, A. S.; Bono, J.; Boiarinov, S.; Briscoe, W. J.; Burkert, V. D.; Carman, D. S.; Careccia, S.; Celentano, A.; Chandavar, S.; Charles, G.; Colaneri, L.; Cole, P. L.; Contalbrigo, M.; Crede, V.; D'Angelo, A.; Dashyan, N.; De Vita, R.; De Sanctis, E.; Deur, A.; Djalali, C.; Dodge, G. E.; Dupre, R.; Egiyan, H.; El Alaoui, A.; El Fassi, L.; Elouadrhiri, L.; Eugenio, P.; Fedotov, G.; Fegan, S.; Filippi, A.; Fleming, J. A.; Fradi, A.; Garillon, B.; Gilfoyle, G. P.; Giovanetti, K. L.; Girod, F. X.; Goetz, J. T.; Gohn, W.; Golovatch, E.; Gothe, R. W.; Griffioen, K. A.; Guegan, B.; Guidal, M.; Guo, L.; Hafidi, K.; Hakobyan, H.; Hanretty, C.; Harrison, N.; Hattawy, M.; Hicks, K.; Holtrop, M.; Hughes, S. M.; Hyde, C. E.; Ilieva, Y.; Ireland, D. G.; Ishkhanov, B. S.; Jenkins, D.; Jiang, H.; Jo, H. S.; Joo, K.; Joosten, S.; Kalantarians, N.; Keller, D.; Khandaker, M.; Kim, A.; Kim, W.; Klein, A.; Klein, F. J.; Koirala, S.; Kubarovsky, V.; Kuhn, S. E.; Livingston, K.; Lu, H. Y.; MacGregor, I. J. D.; Markov, N.; Mattione, P.; Mayer, M.; McKinnon, B.; Mestayer, M. D.; Meyer, C. A.; Mirazita, M.; Mokeev, V.; Montgomery, R. A.; Moody, C. I.; Moutarde, H.; Movsisyan, A.; Camacho, C. Munoz; Nadel-Turonski, P.; Niccolai, S.; Niculescu, G.; Osipenko, M.; Ostrovidov, A. I.; Park, K.; Pasyuk, E.; Peña, C.; Pisano, S.; Pogorelko, O.; Price, J. W.; Procureur, S.; Prok, Y.; Protopopescu, D.; Puckett, A. J. R.; Ripani, M.; Rizzo, A.; Rosner, G.; Rossi, P.; Roy, P.; Sabatié, F.; Salgado, C.; Schott, D.; Schumacher, R. A.; Seder, E.; Sharabian, Y. G.; Simonyan, A.; Skorodumina, I.; Smith, E. S.; Smith, G. D.; Sober, D. I.; Sokhan, D.; Sparveris, N.; Stepanyan, S.; Stoler, P.; Strauch, S.; Sytnik, V.; Taiuti, M.; Tian, Ye; Trivedi, A.; Ungaro, M.; Voskanyan, H.; Voutier, E.; Walford, N. K.; Watts, D. P.; Wei, X.; Wood, M. H.; Zachariou, N.; Zana, L.; Zhang, J.; Zhao, Z. W.; Zonta, I.; CLAS Collaboration

    2015-02-01

    There is a significant discrepancy between the values of the proton electric form factor, GEp, extracted using unpolarized and polarized electron scattering. Calculations predict that small two-photon exchange (TPE) contributions can significantly affect the extraction of GEp from the unpolarized electron-proton cross sections. We determined the TPE contribution by measuring the ratio of positron-proton to electron-proton elastic scattering cross sections using a simultaneous, tertiary electron-positron beam incident on a liquid hydrogen target and detecting the scattered particles in the Jefferson Lab CLAS detector. This novel technique allowed us to cover a wide range in virtual photon polarization (ɛ ) and momentum transfer (Q2) simultaneously, as well as to cancel luminosity-related systematic errors. The cross section ratio increases with decreasing ɛ at Q2=1.45 GeV2 . This measurement is consistent with the size of the form factor discrepancy at Q2≈1.75 GeV2 and with hadronic calculations including nucleon and Δ intermediate states, which have been shown to resolve the discrepancy up to 2 - 3 GeV2 .

  16. Proton form factors and two-photon exchange in elastic electron-proton scattering

    SciTech Connect

    Nikolenko, D. M.; Arrington, J.; Barkov, L. M.; Vries, H. de; Gauzshtein, V. V.; Golovin, R. A.; Gramolin, A. V.; Dmitriev, V. F.; Zhilich, V. N.; Zevakov, S. A.; Kaminsky, V. V.; Lazarenko, B. A.; Mishnev, S. I.; Muchnoi, N. Yu.; Neufeld, V. V.; Rachek, I. A.; Sadykov, R. Sh.; Stibunov, V. N.; Toporkov, D. K.; Holt, R. J.; and others

    2015-05-15

    Proton electromagnetic form factors are among the most important sources of information about the internal structure of the proton. Two different methods for measuring these form factors, the method proposed by Rosenbluth and the polarization-transfer method, yield contradictory results. It is assumed that this contradiction can be removed upon taking into account the hard part of the contribution of two-photon exchange to the cross section for elastic electron-proton scattering. This contribution can measured experimentally via a precision comparison of the cross sections for the elastic scattering of positrons and electrons on protons. Such a measurement, performed at the VEPP-3 storage ring in Novosibirsk at the beam energies of 1.6 and 1.0 GeV for positron (electron) scattering angles in the ranges of θ{sub e} = 15°–25° and 55°–75° in the first case and in the range of θ{sub e} = 65°–105° in the second case is described in the present article. Preliminary results of this experiment and their comparison with theoretical predictions are described.

  17. Towards a Resolution of the Proton Form Factor Problem: New Electron and Positron Scattering Data

    SciTech Connect

    Adikaram, D.; Rimal, D.; Weinstein, L. B.; Raue, B.; Khetarpal, P.; Bennett, R. P.; Arrington, J.; Brooks, W. K.; Adhikari, K. P.; Afanasev, A. V.; Dupre, R.; El Alaoui, A.; El Fassi, L.; Hafidi, K.; Moody, C. I.

    2015-02-10

    There is a significant discrepancy between the values of the proton electric form factor, G(E)(p), extracted using unpolarized and polarized electron scattering. Calculations predict that small two-photon exchange (TPE) contributions can significantly affect the extraction of G(E)(p). from the unpolarized electron-proton cross sections. We determined the TPE contribution by measuring the ratio of positron-proton to electron-proton elastic scattering cross sections using a simultaneous, tertiary electron-positron beam incident on a liquid hydrogen target and detecting the scattered particles in the Jefferson Lab CLAS detector. This novel technique allowed us to cover a wide range in virtual photon polarization (epsilon) and momentum transfer (Q(2)) simultaneously, as well as to cancel luminosity-related systematic errors. The cross section ratio increases with decreasing epsilon at Q(2) = 1.45 GeV2. This measurement is consistent with the size of the form factor discrepancy at Q(2) approximate to 1.75 GeV2 and with hadronic calculations including nucleon and Delta intermediate states, which have been shown to resolve the discrepancy up to 2-3 GeV2.

  18. Towards a Resolution of the Proton Form Factor Problem: New Electron and Positron Scattering Data

    SciTech Connect

    Adikaram, D.; Rimal, D.; Weinstein, L. B.; Raue, B.; Khetarpal, P.; Bennett, R.; Arrington, J.; Brooks, W.; Adhikari, K.; Afanasev, A.; Amaryan, M.; Anderson, M.; Anefalos Pereira, S.; Avakian, H.; Ball, J.; Battaglieri, M.; Bedlinskiy, I.; Biselli, A.; Bono, J.; Boiarinov, S.; Briscoe, W.; Burkert, V.; Carman, D.; Careccia, S.; Celentano, A.; Chandavar, S.; Charles, G.; Colaneri, L.; Cole, P.; Contalbrigo, M.; Crede, V.; D'Angelo, A.; Dashyan, N.; De Vita, R.; De Sanctis, E.; Deur, A.; Djalali, C.; Dodge, G.; Dupre, R.; Egiyan, H.; El Alaoui, A.; El Fassi, L.; Elouadrhiri, L.; Eugenio, P.; Fedotov, G.; Fegan, S.; Filippi, A.; Fleming, J.; Fradi, A.; Garillon, B.; Gilfoyle, G.; Giovanetti, K.; Girod, F.; Goetz, J.; Gohn, W.; Golovatch, E.; Gothe, R.; Griffioen, K.; Guegan, B.; Guidal, M.; Guo, L.; Hafidi, K.; Hakobyan, H.; Hanretty, C.; Harrison, N.; Hattawy, M.; Hicks, K.; Holtrop, M.; Hughes, S.; Hyde, C. E.; Ilieva, Y.; Ireland, D.; Ishkhanov, B.; Jenkins, D.; Jiang, H.; Jo, H.; Joo, K.; Joosten, S.; Kalantarians, N.; Keller, D.; Khandaker, M.; Kim, A.; Kim, W.; Klein, A.; Klein, F.; Koirala, S.; Kubarovsky, V.; Kuhn, S.; Livingston, K.; Lu, H.; MacGregor, I.; Markov, N.; Mattione, P.; Mayer, M.; McKinnon, B.; Mestayer, M.; Meyer, C.; Mirazita, M.; Mokeev, V.; Montgomery, R.; Moody, C.; Moutarde, H.; Movsisyan, A.; Camacho, C. Munoz; Nadel-Turonski, P.; Niccolai, S.; Niculescu, G.; Osipenko, M.; Ostrovidov, A.; Park, K.; Pasyuk, E.; Pisano, S.; Pogorelko, O.; Price, J.; Procureur, S.; Prok, Y.; Protopopescu, D.; Puckett, A.; Ripani, M.; Rizzo, A.; Rosner, G.; Rossi, P.; Roy, P.; Sabati, F.; Salgado, C.; Schott, D.; Schumacher, R.; Seder, E.; Sharabian, Y.; Simonyan, A.; Skorodumina, I.; Smith, E.; Smith, G.; Sober, D.; Sokhan, D.; Sparveris, N.; Stepanyan, S.; Stoler, P.; Strauch, S.; Sytnik, V.; Taiuti, M.; Tian, Ye; Trivedi, A.; Ungaro, M.; Voskanyan, H.; Voutier, E.; Walford, N.; Watts, D.; Wei, X.; Wood, M.; Zachariou, N.; Zana, L.; Zhang, J.; Zhao, Z.; Zonta, I.

    2015-02-10

    There is a significant discrepancy between the values of the proton electric form factor, GpE, extracted using unpolarized and polarized electron scattering. Calculations predict that small two-photon exchange (TPE) contributions can significantly affect the extraction of GpE from the unpolarized electron-proton cross sections. We determined the TPE contribution by measuring the ratio of positron-proton to electron-proton elastic scattering cross sections using a simultaneous, tertiary electron-positron beam incident on a liquid hydrogen target and detecting the scattered particles in the Jefferson Lab CLAS detector. This novel technique allowed us to cover a wide range in virtual photon polarization (epsilon) and momentum transfer (Q2) simultaneously, as well as to cancel luminosity-related systematic errors. The cross section ratio increases with decreasing ε at Q2=1.45 GeV2. This measurement is consistent with the size of the form factor discrepancy at Q2≈1.75 GeV2 and with hadronic calculations including nucleon and Delta intermediate states, which have been shown to resolve the discrepancy up to 2-3 GeV2.

  19. Towards a Resolution of the Proton Form Factor Problem: New Electron and Positron Scattering Data

    DOE PAGESBeta

    Adikaram, D.; Rimal, D.; Weinstein, L. B.; Raue, B.; Khetarpal, P.; Bennett, R.; Arrington, J.; Brooks, W.; Adhikari, K.; Afanasev, A.; et al

    2015-02-10

    There is a significant discrepancy between the values of the proton electric form factor, GpE, extracted using unpolarized and polarized electron scattering. Calculations predict that small two-photon exchange (TPE) contributions can significantly affect the extraction of GpE from the unpolarized electron-proton cross sections. We determined the TPE contribution by measuring the ratio of positron-proton to electron-proton elastic scattering cross sections using a simultaneous, tertiary electron-positron beam incident on a liquid hydrogen target and detecting the scattered particles in the Jefferson Lab CLAS detector. This novel technique allowed us to cover a wide range in virtual photon polarization (epsilon) and momentummore » transfer (Q2) simultaneously, as well as to cancel luminosity-related systematic errors. The cross section ratio increases with decreasing ε at Q2=1.45 GeV2. This measurement is consistent with the size of the form factor discrepancy at Q2≈1.75 GeV2 and with hadronic calculations including nucleon and Delta intermediate states, which have been shown to resolve the discrepancy up to 2-3 GeV2.« less

  20. Towards a resolution of the proton form factor problem: new electron and positron scattering data.

    PubMed

    Adikaram, D; Rimal, D; Weinstein, L B; Raue, B; Khetarpal, P; Bennett, R P; Arrington, J; Brooks, W K; Adhikari, K P; Afanasev, A V; Amaryan, M J; Anderson, M D; Anefalos Pereira, S; Avakian, H; Ball, J; Battaglieri, M; Bedlinskiy, I; Biselli, A S; Bono, J; Boiarinov, S; Briscoe, W J; Burkert, V D; Carman, D S; Careccia, S; Celentano, A; Chandavar, S; Charles, G; Colaneri, L; Cole, P L; Contalbrigo, M; Crede, V; D'Angelo, A; Dashyan, N; De Vita, R; De Sanctis, E; Deur, A; Djalali, C; Dodge, G E; Dupre, R; Egiyan, H; El Alaoui, A; El Fassi, L; Elouadrhiri, L; Eugenio, P; Fedotov, G; Fegan, S; Filippi, A; Fleming, J A; Fradi, A; Garillon, B; Gilfoyle, G P; Giovanetti, K L; Girod, F X; Goetz, J T; Gohn, W; Golovatch, E; Gothe, R W; Griffioen, K A; Guegan, B; Guidal, M; Guo, L; Hafidi, K; Hakobyan, H; Hanretty, C; Harrison, N; Hattawy, M; Hicks, K; Holtrop, M; Hughes, S M; Hyde, C E; Ilieva, Y; Ireland, D G; Ishkhanov, B S; Jenkins, D; Jiang, H; Jo, H S; Joo, K; Joosten, S; Kalantarians, N; Keller, D; Khandaker, M; Kim, A; Kim, W; Klein, A; Klein, F J; Koirala, S; Kubarovsky, V; Kuhn, S E; Livingston, K; Lu, H Y; MacGregor, I J D; Markov, N; Mattione, P; Mayer, M; McKinnon, B; Mestayer, M D; Meyer, C A; Mirazita, M; Mokeev, V; Montgomery, R A; Moody, C I; Moutarde, H; Movsisyan, A; Camacho, C Munoz; Nadel-Turonski, P; Niccolai, S; Niculescu, G; Osipenko, M; Ostrovidov, A I; Park, K; Pasyuk, E; Peña, C; Pisano, S; Pogorelko, O; Price, J W; Procureur, S; Prok, Y; Protopopescu, D; Puckett, A J R; Ripani, M; Rizzo, A; Rosner, G; Rossi, P; Roy, P; Sabatié, F; Salgado, C; Schott, D; Schumacher, R A; Seder, E; Sharabian, Y G; Simonyan, A; Skorodumina, I; Smith, E S; Smith, G D; Sober, D I; Sokhan, D; Sparveris, N; Stepanyan, S; Stoler, P; Strauch, S; Sytnik, V; Taiuti, M; Tian, Ye; Trivedi, A; Ungaro, M; Voskanyan, H; Voutier, E; Walford, N K; Watts, D P; Wei, X; Wood, M H; Zachariou, N; Zana, L; Zhang, J; Zhao, Z W; Zonta, I

    2015-02-13

    There is a significant discrepancy between the values of the proton electric form factor, G(E)(p), extracted using unpolarized and polarized electron scattering. Calculations predict that small two-photon exchange (TPE) contributions can significantly affect the extraction of G(E)(p) from the unpolarized electron-proton cross sections. We determined the TPE contribution by measuring the ratio of positron-proton to electron-proton elastic scattering cross sections using a simultaneous, tertiary electron-positron beam incident on a liquid hydrogen target and detecting the scattered particles in the Jefferson Lab CLAS detector. This novel technique allowed us to cover a wide range in virtual photon polarization (ϵ) and momentum transfer (Q(2)) simultaneously, as well as to cancel luminosity-related systematic errors. The cross section ratio increases with decreasing ϵ at Q(2)=1.45  GeV(2). This measurement is consistent with the size of the form factor discrepancy at Q(2)≈1.75  GeV(2) and with hadronic calculations including nucleon and Δ intermediate states, which have been shown to resolve the discrepancy up to 2-3  GeV(2). PMID:25723209

  1. Patterns, aetiology and risk factors of intimate partner violence-related injuries to head, neck and face in Chinese women

    PubMed Central

    2014-01-01

    Background Intimate partner violence (IPV) related injuries have been recognized among health care professionals. However, few studies have provided detailed information on injuries to the head, neck and face regions in Chinese women. As abused Chinese women are generally unwilling to disclose IPV and there are differences in socio-demographic characteristics, societal norms and behaviours, the women may exhibit different patterns, aetiology and risk factors of IPV-related HNF injuries. This study aims to examine the patterns of head, neck and face injuries presenting to Accident and Emergency departments, including the anatomical regions, types, severity, aetiology and demographic and non-demographic risk factors of injuries inflicted by intimate partners in Chinese context. Methods Medical charts of 223 women presented to the Accident and Emergency departments of two regional hospitals in Hong Kong between January 2010 and December 2011 were reviewed independently by two reviewers. Results Head, neck and face injuries remained the most common injuries found in abused Chinese women (77.6%), and punching with a fist was the most common aetiology (60.2%). In particular, punching with a fist was significantly associated on the upper third of the maxillofacial region (p = .01) and the back part of the head (p = .03). Moreover, cohabiting and separated women were more likely to have multiple injuries than those who were married (OR = 3.3, 95% CI = 1.4, 7.8; OR = 2.1, 95% CI = .4, 11.9). Conclusions The findings enhance the understanding of head, neck and face injuries and inform clinicians about the linkage among injuries and risks in abused Chinese women. PMID:24410868

  2. Correction: Towards improved precision in the quantification of surface-enhanced Raman scattering (SERS) enhancement factors: a renewed approach.

    PubMed

    Sivanesan, Arumugam; Adamkiewicz, Witold; Kalaivani, Govindasamy; Kamińska, Agnieszka; Waluk, Jacek; Hołyst, Robert; Izake, Emad L

    2015-01-21

    Correction for 'Towards improved precision in the quantification of surface-enhanced Raman scattering (SERS) enhancement factors: a renewed approach' by Arumugam Sivanesan et al., Analyst, 2015, DOI:10.1039/c4an01778a PMID:25453040

  3. Sensor and Display Human Factors Based Design Constraints for Head Mounted and Tele-Operation Systems

    PubMed Central

    Harrison, Andre; Mullins, Linda; Etienne-Cummings, Ralph

    2011-01-01

    For mobile imaging systems in head mounted displays and tele-operation systems it is important to maximize the amount of visual information transmitted to the human visual system without exceeding its input capacity. This paper aims to describe the design constraints on the imager and display systems of head mounted devices and tele-operated systems based upon the capabilities of the human visual system. We also present the experimental results of methods to improve the amount of visual information conveyed to a user when trying to display a high dynamic range image on a low dynamic range display. PMID:22319370

  4. Keratinocyte growth factor and hepatocyte growth factor/scatter factor are heparin-binding growth factors for alveolar type II cells in fibroblast-conditioned medium.

    PubMed Central

    Panos, R J; Rubin, J S; Csaky, K G; Aaronson, S A; Mason, R J

    1993-01-01

    Epithelial-mesenchymal interactions mediate aspects of normal lung growth and development and are important in the restoration of normal alveolar architecture after lung injury. To determine if fibroblasts are a source of soluble growth factors for alveolar type II cells, we investigated the effect of fibroblast-conditioned medium (CM) on alveolar type II cell DNA synthesis. Serum-free CM from confluent adult human lung fibroblasts was concentrated fivefold by lyophilization. Type II cells were isolated from adult rats by elastase dissociation and incubated with [3H]thymidine and varying dilutions of concentrated CM and serum from day 1 to 3 of culture. Stimulation of type II cell DNA synthesis by fibroblast-CM was maximal after 48 h of conditioning and required the presence of serum. The activity of the CM was eliminated by boiling and by treatment with trypsin, pepsin, or dithiothreitol and was additive with saturating concentrations of acidic fibroblast growth factor, epidermal growth factor, and insulin. The growth factor activity bound to heparin-Sepharose and was eluted with 0.6 and 1.0 M NaCl. Neutralizing antibody studies demonstrated that the primary mitogens isolated in the 0.6 and 1.0 M NaCl fractions were keratinocyte growth factor (KGF, fibroblast growth factor 7) and hepatocyte growth factor/scatter factor (HGF/SF), respectively. HGF/SF was demonstrated in the crude CM and KGF was detected in the 0.6 M NaCl eluent by immunoblotting. Northern blot analysis confirmed that the lung fibroblasts expressed both KGF and HGF/SF transcripts. Human recombinant KGF and HGF/SF induced a concentration- and serum-dependent increase in rat alveolar type II cell DNA synthesis. We conclude that adult human lung fibroblasts produce at least two soluble heparin-binding growth factors, KGF and HGF/SF, which promote DNA synthesis and proliferation of rat alveolar type II cells in primary culture. KGF and HGF/SF may be important stimuli for alveolar type II cell

  5. Four-jet production in single- and double-parton scattering within high-energy factorization

    NASA Astrophysics Data System (ADS)

    Kutak, Krzysztof; Maciula, Rafal; Serino, Mirko; Szczurek, Antoni; van Hameren, Andreas

    2016-04-01

    We perform a first study of 4-jet production in a complete high-energy factorization (HEF) framework. We include and discuss contributions from both single-parton scattering (SPS) and double-parton scattering (DPS). The calculations are performed for kinematical situations relevant for two experimental measurements (ATLAS and CMS) at the LHC. We compare our results to those reported by the ATLAS and CMS collaborations for different sets of kinematical cuts. The results of the HEF approach are compared with their counterparts for collinear factorization. For symmetric cuts the DPS HEF result is considerably smaller than the one obtained with collinear factorization. The mechanism leading to this difference is of kinematical nature. We conclude that an analysis of inclusive 4-jet production with asymmetric p T -cuts below 50 GeV would be useful to enhance the DPS contribution relative to the SPS contribution. In contrast to the collinear approach, the HEF approach nicely describes the distribution of the Δ S variable, which involves all four jets and their angular correlations.

  6. Resolving the Proton Form Factor Problem with Positron-Proton Scattering

    NASA Astrophysics Data System (ADS)

    Weinstein, Lawrence

    2012-10-01

    The proton electromagnetic form factors are essential pieces of our knowledge of nucleon structure. However, Rosenbluth separation measurements of the proton electric form factor, GE(Q^2), differ from polarization transfer measurements by a factor of three at Q^2 = 5.6 (GeV/c)^2. This discrepancy must be resolved. One possible resolution is to include the contribution of hard two-photon exchange (TPE) contributions. These contributions are very difficult to calculate. However, we can directly determine the TPE effect by measuring the ratio of the positron-proton to electron-proton elastic scattering cross sections, R=σ(e^+p)/σ(e^-p), because the TPE amplitude has the same sign as the e^+p born amplitude and the opposite sign as the e^-p born amplitude. We have measured R over a wide range of momentum transfer, 0.2 <=Q^2 <=2 GeV^2, and virtual photon polarization, 0.1 <=ɛ<=0.9, using a mixed identical beam of electrons and positrons in Hall B at Jefferson Lab. This talk will describe the experimental techniques used to produce this beam, the analysis techniques to identify elastic scattering events, and some preliminary results.

  7. Scatter factor influences the formation of prostate epithelial cell colonies on bone marrow stroma in vitro.

    PubMed

    Lang, S H; Clarke, N W; George, N J; Testa, N G

    1999-06-01

    Prostate cancer metastases form selectively in the bone marrow. Previously we demonstrated motility was important for the formation of primary prostatic epithelial cell colonies in bone marrow stroma (BMS) co-culture. In this study we looked at the influence of motility factors on the colony formation of epithelial cells derived from benign (bPEC) or malignant (mPEC) prostate tissue. After 7 days co-culture we found that anti-scatter factor consistently inhibited prostate epithelial cell colony formation on BMS (7/7 mPEC and 4/7 bPEC samples showed significant inhibition). Antibodies against bFGF and 5T4 did not significantly affect colony formation. Addition of fibroblast conditioned media (derived from benign prostates) to co-cultures stimulated the colony formation of bPEC (170%) and mPEC (252%). This stimulation was eliminated by depletion of SF from the conditioned media. Immunohistochemical staining found c-Met expression in 5/6 bPEC cultures and 7/9 mPEC cultures. When grown in BMS co-culture expression of c-Met was positive in 3/6 bPEC and 2/7 mPEC samples. In conclusion, scatter factor influences the in vitro formation of prostate epithelial cell colonies on BMS co-culture. PMID:10545020

  8. DetOx: a program for determining anomalous scattering factors of mixed-oxidation-state species.

    PubMed

    Sutton, Karim J; Barnett, Sarah A; Christensen, Kirsten E; Nowell, Harriott; Thompson, Amber L; Allan, David R; Cooper, Richard I

    2013-01-01

    Overlapping absorption edges will occur when an element is present in multiple oxidation states within a material. DetOx is a program for partitioning overlapping X-ray absorption spectra into contributions from individual atomic species and computing the dependence of the anomalous scattering factors on X-ray energy. It is demonstrated how these results can be used in combination with X-ray diffraction data to determine the oxidation state of ions at specific sites in a mixed-valance material, GaCl(2). PMID:23254676

  9. Parity-Violating Electron Deuteron Scattering and the Proton's Neutral Weak Axial Vector Form Factor

    SciTech Connect

    Ito, Takeyasu; Averett, Todd; Barkhuff, David; Batigne, Guillaume; Beck, Douglas; Beise, Elizabeth; Blake, A.; Breuer, Herbert; Carr, Robert; Clasie, Benjamin; Covrig, Silviu; Danagoulian, Areg; Dodson, George; Dow, Karen; Dutta, Dipangkar; Farkhondeh, Manouchehr; Filippone, Bradley; FRANKLIN, W.; Furget, Christophe; Gao, Haiyan; Gao, Juncai; Gustafsson, Kenneth; Hannelius, Lars; Hasty, R.; Allen, Alice; Herda, M.C.; Jones, CE; King, Paul; Korsch, Wolfgang; Kowalski, Stanley; Kox, Serge; Kramer, Kevin; Lee, P.; Liu, Jinghua; Martin, Jeffery; McKeown, Robert; Mueller, B.; Pitt, Mark; Plaster, Bradley; Quemener, Gilles; Real, Jean-Sebastien; Ritter, J.; Roche, Julie; Savu, V.; Schiavilla, Rocco; Seely, Charles; Spayde, Damon; Suleiman, Riad; Taylor, S.; Tieulent, Raphael; Tipton, Bryan; Tsentalovich, E.; Wells, Steven; Yang, Bin; Yuan, Jing; Yun, Junho; Zwart, Townsend

    2004-03-01

    We report on a new measurement of the parity-violating asymmetry in quasielastic electron scattering from the deuteron at backward angles at Q2 = 0.038 (GeV/c)2. This quantity provides a determination of the neutral weak axial vector form factor of the nucleon, which can potentially receive large electroweak corrections. The measured asymmetry A = z3.51±0.57 (stat)±0.58 (syst) ppm is consistent with theoretical predictions. We also report on updated results of the previous experiment at Q2 = 0.091 (GeV/c)2, which are also consistent with theoretical predictions.

  10. A modification of the factorization method for the classical acoustic inverse scattering problems

    NASA Astrophysics Data System (ADS)

    Kirsch, Andreas; Liu, Xiaodong

    2014-03-01

    It is well-known that sampling type methods for solving inverse scattering problems fail if the wave number is an eigenvalue of a corresponding interior eigenvalue problem. By adding the far field patterns corresponding to an artificial ball lying within the obstacle and imposing an impedance boundary condition on the boundary of this ball we propose a modification of the factorization method which provides the characterization of the unknown obstacle for all wave numbers. Some numerical experiments are presented to demonstrate the feasibility and effectiveness of our method.

  11. X-ray Intermolecular Structure Factor (XISF): separation of intra- and intermolecular interactions from total X-ray scattering data

    SciTech Connect

    Mou, Q.; Benmore, C. J.; Yarger, J. L.

    2015-06-01

    XISF is a MATLAB program developed to separate intermolecular structure factors from total X-ray scattering structure factors for molecular liquids and amorphous solids. The program is built on a trust-region-reflective optimization routine with the r.m.s. deviations of atoms physically constrained. XISF has been optimized for performance and can separate intermolecular structure factors of complex molecules.

  12. Early Head Start: Factors Associated with Caregiver Knowledge of Child Development, Parenting Behavior, and Parenting Stress

    ERIC Educational Resources Information Center

    Belcher, Harolyn M. E.; Watkins, Katara; Johnson, Elizabeth; Ialongo, Nicholas

    2007-01-01

    This study investigates the role of socioeconomic status, parental mental health, and knowledge of child development on parenting styles and perceived parenting stress in caregivers of children, ages 3 months to 3 years, enrolled in Early Head Start (EHS). Caregivers of EHS students were interviewed using the Knowledge of Infant Development…

  13. Factors Leading to Variability of Emission Factors, Single Scattering Albedo, and Elemental Carbon Fraction from Biofuel Emissions

    NASA Astrophysics Data System (ADS)

    Roden, C. A.; Bond, T. C.; Conway, S.; Osorto Pinel, B.; Maccarty, N.

    2006-12-01

    In a three-year study of field and laboratory emissions of traditional and improved biofuel cookstoves, we found that field measured particulate emissions of actual cooking events average 2.5 times those of reproduced lab emissions. Emission factors are highly dependent on the care and skill of the operator, and the resulting combustion; these do not appear to be accurately reproduced in the lab. The single scatter albedo (SSA) of the emissions is very low in both lab and field measurements, averaging about 0.3 for lab tests and around 0.5 for field tests, indicating that the primary particles are climate warming. In Honduras, improved stoves generally had lower emission factors than traditional stoves. Over the course of 3 summers we have measured field emissions from traditional cookstoves, relatively-new improved cookstoves, and "broken-in" improved cookstoves. For improved stoves, the presence of a chimney generally resulted in lower emission factors but left the SSA unaffected. Traditional cookstoves had an average PM emission factor of 8.5 g/kg significantly larger than previous studies. Particulate emission factors for improved cookstoves without and with chimneys averaged about 5.7 g/kg and 3.5 g/kg respectively. The elemental carbon (EC) fraction of PM varied significantly between individual tests, but averaged about 25% for each of the categories. Wood type affects on the PM emission factor, the SSA of the emissions and EC fraction. During our 2006 field measurements, we performed multiple emission measurements on the same stove while varying the fuel. Pine wood generally produced more PM than oak per kilogram of fuel. Additionally, Ocote, a resinous pitch pine often used in Central America for lighting fires, produces emissions which have a very low SSA and high EC fraction. We present the elemental carbon fraction and mass emission factors for different type of stoves and testing conditions. We summarize the characteristics of the particles emitted

  14. Derivation of factors for estimating the scatter of diagnostic x-rays from walls and ceiling slabs.

    PubMed

    Martin, C J; Sutton, D G; Magee, J; McVey, S; Williams, J R; Peet, D

    2012-12-01

    Computed tomography (CT) scanning rooms and interventional x-ray facilities with heavy workloads may require the installation of shielding to protect against radiation scattered from walls or ceiling slabs. This is particularly important for the protection of those operating x-ray equipment from within control cubicles who may be exposed to radiation scattered from the ceiling over the top of the protective barrier and round the side if a cubicle door is not included. Data available on the magnitude of this tertiary scatter from concrete slabs are limited. Moreover, there is no way in which tertiary scatter levels can be estimated easily for specific facilities. There is a need for a suitable method for quantification of tertiary scatter because of the increases in workloads of complex x-ray facilities. In this study diagnostic x-ray air kerma levels scattered from concrete and brick walls have been measured to verify scatter factors. The results have been used in a simulation of tertiary scatter for x-ray facilities involving summation of scatter contributions from elements across concrete ceiling slabs. The majority of the ceiling scatter air kerma to which staff behind a barrier will be exposed arises from the area between the patient/x-ray tube and the staff. The level depends primarily on the heights of the ceiling and protective barrier. A method has been developed to allow tertiary scatter levels to be calculated using a simple equation based on a standard arrangement for rooms with different ceiling and barrier heights. Coefficients have been derived for a CT facility and an interventional suite to predict tertiary scatter levels from the workload, so that consideration can be given to the protection options available. PMID:23006642

  15. Electron-scattering form factors for 6Li in the ab initio symmetry-guided framework

    NASA Astrophysics Data System (ADS)

    Dytrych, T.; Hayes, A. C.; Launey, K. D.; Draayer, J. P.; Maris, P.; Vary, J. P.; Langr, D.; Oberhuber, T.

    2015-02-01

    We present an ab initio symmetry-adapted no-core shell-model description for 6Li. We study the structure of the ground state of 6Li and the impact of the symmetry-guided space selection on the charge density components for this state in momentum space, including the effect of higher shells. We accomplish this by investigating the electron scattering charge form factor for momentum transfers up to q ˜4 fm-1 . We demonstrate that this symmetry-adapted framework can achieve significantly reduced dimensions for equivalent large shell-model spaces while retaining the accuracy of the form factor for any momentum transfer. These new results confirm the previous outcomes for selected spectroscopy observables in light nuclei, such as binding energies, excitation energies, electromagnetic moments, E 2 and M 1 reduced transition probabilities, as well as point-nucleon matter rms radii.

  16. Near-infrared spectroscopy of the adult head: effect of scattering and absorbing obstructions in the cerebrospinal fluid layer on light distribution in the tissue.

    PubMed

    Dehghani, H; Delpy, D T

    2000-09-01

    Previous modeling of near-infrared (NIR) light distribution in models of the adult head incorporating a clear nonscattering cerebrospinal fluid (CSF) layer have shown the latter to have a profound effect on the resulting photon measurement density function (PMDF). In particular, the presence of the CSF limits the PMDF largely to the outer cortical gray matter with little signal contribution from the deeper white matter. In practice, the CSF is not a simple unobstructed clear layer but contains light-scattering membranes and is crossed by various blood vessels. Using a radiosity-diffusion finite-element model, we investigated the effect on the PMDF of introducing intrusions within the clear layer. The results show that the presence of such obstructions does not significantly increase the light penetration into the brain tissue, except immediately adjacent to the obstruction and that its presence also increases the light sampling of the adjacent skull tissues, which would lead to additional contamination of the NIR spectroscopy signal by the surface tissue layers. PMID:18350064

  17. Mouse Y-Encoded Transcription Factor Zfy2 Is Essential for Sperm Head Remodelling and Sperm Tail Development

    PubMed Central

    Vernet, Nadege; Mahadevaiah, Shantha K.; Decarpentrie, Fanny; Longepied, Guy; de Rooij, Dirk G.; Burgoyne, Paul S.; Mitchell, Michael J.

    2016-01-01

    A previous study indicated that genetic information encoded on the mouse Y chromosome short arm (Yp) is required for efficient completion of the second meiotic division (that generates haploid round spermatids), restructuring of the sperm head, and development of the sperm tail. Using mouse models lacking a Y chromosome but with varying Yp gene complements provided by Yp chromosomal derivatives or transgenes, we recently identified the Y-encoded zinc finger transcription factors Zfy1 and Zfy2 as the Yp genes promoting the second meiotic division. Using the same mouse models we here show that Zfy2 (but not Zfy1) contributes to the restructuring of the sperm head and is required for the development of the sperm tail. The preferential involvement of Zfy2 is consistent with the presence of an additional strong spermatid-specific promotor that has been acquired by this gene. This is further supported by the fact that promotion of sperm morphogenesis is also seen in one of the two markedly Yp gene deficient models in which a Yp deletion has created a Zfy2/1 fusion gene that is driven by the strong Zfy2 spermatid-specific promotor, but encodes a protein almost identical to that encoded by Zfy1. Our results point to there being further genetic information on Yp that also has a role in restructuring the sperm head. PMID:26765744

  18. Effect of the pair-structure factor of a particulate medium on scalar wave scattering in the first Born approximation.

    PubMed

    Sahin, Serkan; Korotkova, Olga

    2009-06-15

    Using scattering matrices and the angular spectrum representation of waves, we develop the analytical theory of scattering of random scalar waves from random collections of particles, valid under the first Born approximation. We demonstrate that in the calculation of far-field statistics, such as the spectral density and the spectral degree of coherence, the knowledge of the pair-structure factor of the collection is crucial. We illustrate our analytical approach by considering a numerical example involving scattering of two partially correlated plane waves from a random distribution of spheres. PMID:19529695

  19. Factors Associated With Long-Term Dysphagia After Definitive Radiotherapy for Locally Advanced Head-and-Neck Cancer

    SciTech Connect

    Caudell, Jimmy J.; Schaner, Philip E.; Meredith, Ruby F.; Locher, Julie L.; Nabell, Lisle M.; Carroll, William R.; Magnuson, J. Scott; Spencer, Sharon A.; Bonner, James A.

    2009-02-01

    Purpose: The use of altered fractionation radiotherapy (RT) regimens, as well as concomitant chemotherapy and RT, to intensify therapy for locally advanced head-and-neck cancer can lead to increased rates of long-term dysphagia. Methods and Materials: We identified 122 patients who had undergone definitive RT for locally advanced head-and-neck cancer, after excluding those who had been treated for a second or recurrent head-and-neck primary, had Stage I-II disease, developed locoregional recurrence, had <12 months of follow-up, or had undergone postoperative RT. The patient, tumor, and treatment factors were correlated with a composite of 3 objective endpoints as a surrogate for severe long-term dysphagia: percutaneous endoscopic gastrostomy tube dependence at the last follow-up visit; aspiration on a modified barium swallow study or a clinical diagnosis of aspiration pneumonia; or the presence of a pharyngoesophageal stricture. Results: A composite dysphagia outcome occurred in 38.5% of patients. On univariate analysis, the primary site (p = 0.01), use of concurrent chemotherapy (p = 0.01), RT schedule (p = 0.02), and increasing age (p = 0.04) were significantly associated with development of composite long-term dysphagia. The use of concurrent chemotherapy (p = 0.01), primary site (p = 0.02), and increasing age (p = 0.02) remained significant on multivariate analysis. Conclusion: The addition of concurrent chemotherapy to RT for locally advanced head-and-neck cancer resulted in increased long-term dysphagia. Early intervention using swallowing exercises, avoidance of nothing-by-mouth periods, and the use of intensity-modulated RT to reduce the dose to the uninvolved swallowing structures should be explored further in populations at greater risk of long-term dysphagia.

  20. Reply to ``Comment on `Spectroscopic factors for bound s-wave states derived from neutron scattering lengths' ''

    NASA Astrophysics Data System (ADS)

    Mohr, P.; Herndl, H.; Oberhummer, H.; Staudt, G.

    1997-12-01

    In a recent comment Barker [Phys. Rev. C 56, 3423 (1997), the preceding paper] criticized our procedure for the extraction of spectroscopic factors from neutron scattering lengths [Phys. Rev. C 55, 1591 (1997)]. In this reply we compare the R-matrix analysis by Barker to our potential model calculation, and we discuss the applicability of both models for the extraction of spectroscopic factors.

  1. The role of multiple scattering in twilight zenith sky observations of atmospheric absorbers: Diurnal photochemistry and airmass factors

    NASA Astrophysics Data System (ADS)

    Perliski, Lori Mac

    The ability to properly interpret UV-visible twilight absorption measurements of atmospheric chemical constituents is dependent on how well the optical path, or airmass factor, of light collected by the spectrometer is understood. In the case of direct light measurement, the airmass factor may be calculated from simple geometrical considerations for a spherical atmosphere. In the case of scattered light, a spherical radiative transfer model must be used. A simple single scattering model and a Monte Carlo radiative transfer scheme were developed to study the effects of multiple scattering, aerosol scattering, albedo and refraction on scattered light airmass factors. Stratospheric airmass factors are found to be relatively insensitive to multiple scattering, albedo, refraction and aerosol scattering by background aerosols at fairly short visible wavelengths (about 450 nm). Tropospheric airmass factors, on the other hand, are very sensitive to these processes. Ground albedo, refraction, multiple scattering and aerosol scattering are also important in determining photolysis rates of atmospheric species. It is found that one-dimensional photochemical model calculations of vertical column abundances of several stratospheric chemical constituents are relatively insensitive to changes in photolysis rates due to albedo, refraction and background aerosol scattering, although they are sensitive to multiple scattering. Following the June 1991 eruption of Mt. Pinatubo, OClO and BrO were observed at Fritz Peak Observatory for the first time every. The radiative and photochemical effects of the presence of Pinatubo volcanic aerosols are examined using a one-dimensional photochemical model coupled to a spherical matrix inversion radiative transfer model. Although the heterogeneous removal of NO(x) is not explicitly considered in the photochemical model, the photochemical effects of NO(x) removal may be studied by prescribing the amount of NO(x) removed by heterogeneous chemistry

  2. Hall scattering factors in p-type 4H-SiC with various doping concentrations

    NASA Astrophysics Data System (ADS)

    Asada, Satoshi; Okuda, Takafumi; Kimoto, Tsunenobu; Suda, Jun

    2016-04-01

    The Hall scattering factor (γH) in p-type 4H-SiC with various aluminum doping concentrations of 5.8 × 1014-7.1 × 1018 cm-3 was investigated from 300 to 900 K. γH was determined by comparing the Hall coefficient with the theoretical carrier concentration derived from acceptor and donor concentrations obtained from secondary ion mass spectrometry and capacitance-voltage measurements. γH decreased with increasing temperature or doping concentration; γH = 1-0.4 for the doping concentration of 5.8 × 1014 cm-3 and γH = 0.5-0.2 for the doping concentration of 7.1 × 1018 cm-3. The dependence might be caused by the anisotropic and nonparabolic valence band structure of 4H-SiC.

  3. Evaluation of time-resolved multi-distance methods to retrieve absorption and reduced scattering coefficients of adult heads in vivo: Optical parameters dependences on geometrical structures of the models used to calculate reflectance

    NASA Astrophysics Data System (ADS)

    Tanifuji, T.

    2016-03-01

    Time-resolved multi-distance measurements are studied to retrieve absorption and reduced scattering coefficients of adult heads, which have enough depth sensitivity to determine the optical parameters in superficial tissues and brain separately. Measurements were performed by putting the injection and collection fibers on the left semi-sphere of the forehead, with the injection fiber placed toward the temporal region, and by moving the collection fiber between 10 and 60 mm from the central sulcus. It became clear that optical parameters of the forehead at all collection fibers were reasonably determined by selecting the appropriate visibility length of the geometrical head models, which is related to head surface curvature at each position.

  4. Vascular endothelial growth factor -634G/C polymorphism associated with osteonecrosis of the femoral head in a Chinese population.

    PubMed

    Liu, Bin; Cao, Yang; Wang, Dawei; Yao, Guijun; Bi, Zhenggang

    2012-07-01

    An impeded blood flow through the femoral head is incriminated in the etiopathogenesis of osteonecrosis of the femoral head (ONFH). Vascular endothelial growth factor (VEGF) is a strong angiogenic protein and also plays a role in the formation of cartilage and bone. The aim of this study was to evaluate the association of VEGF -634G/C polymorphism with ONFH in a Chinese population. A total of 220 unrelated patients with nontraumatic ONFH and 220 unrelated control subjects were consecutively enrolled in a hospital-based case-control study. A polymerase chain reaction-restriction fragment length polymorphism analysis was used to detect the VEGF -634G/C genotype. Patients with ONFH had a significantly higher frequency of the CC genotype (odds ratio=1.64, 95% confidence interval=1.03, 2.60; p=0.04) than controls. There were no significant associations between any genotypes and the cause of ONFH. Our results support the hypothesis that the VEGF -634CC genotype is a risk factor of ONFH in the Chinese population. However, current results should be validated prospectively in larger cohorts. PMID:22612467

  5. Factors affecting breeding season survival of Red-Headed Woodpeckers in South Carolina.

    SciTech Connect

    Kilgo, John, C.; Vukovich, Mark

    2011-11-18

    Red-headed woodpecker (Melanerpes erythrocephalus) populations have declined in the United States and Canada over the past 40 years. However, few demographic studies have been published on the species and none have addressed adult survival. During 2006-2007, we estimated survival probabilities of 80 radio-tagged red-headed woodpeckers during the breeding season in mature loblolly pine (Pinus taeda) forests in South Carolina. We used known-fate models in Program MARK to estimate survival within and between years and to evaluate the effects of foliar cover (number of available cover patches), snag density treatment (high density vs. low density), and sex and age of woodpeckers. Weekly survival probabilities followed a quadratic time trend, being lowest during mid-summer, which coincided with the late nestling and fledgling period. Avian predation, particularly by Cooper's (Accipiter cooperii) and sharp-shinned hawks (A. striatus), accounted for 85% of all mortalities. Our best-supported model estimated an 18-week breeding season survival probability of 0.72 (95% CI = 0.54-0.85) and indicated that the number of cover patches interacted with sex of woodpeckers to affect survival; females with few available cover patches had a lower probability of survival than either males or females with more cover patches. At the median number of cover patches available (n = 6), breeding season survival of females was 0.82 (95% CI = 0.54-0.94) and of males was 0.60 (95% CI = 0.42-0.76). The number of cover patches available to woodpeckers appeared in all 3 of our top models predicting weekly survival, providing further evidence that woodpecker survival was positively associated with availability of cover. Woodpecker survival was not associated with snag density. Our results suggest that protection of {ge}0.7 cover patches per ha during vegetation control activities in mature pine forests will benefit survival of this Partners In Flight Watch List species.

  6. Heads Up

    MedlinePlus

    ... Juvenil HEADS UP to School Sports Online Concussion Training Coaches Parents Athletes Sports Officials HEADS UP to Schools School Nurses Teachers, Counselors, and School Professionals Parents HEADS UP ...

  7. Factors for inconsistent aerosol single scattering albedo between SKYNET and AERONET

    NASA Astrophysics Data System (ADS)

    Khatri, P.; Takamura, T.; Nakajima, T.; Estellés, V.; Irie, H.; Kuze, H.; Campanelli, M.; Sinyuk, A.; Lee, S.-M.; Sohn, B. J.; Pandithurai, G.; Kim, S.-W.; Yoon, S. C.; Martinez-Lozano, J. A.; Hashimoto, M.; Devara, P. C. S.; Manago, N.

    2016-02-01

    SKYNET and Aerosol Robotic Network (AERONET) retrieved aerosol single scattering albedo (SSA) values of four sites, Chiba (Japan), Pune (India), Valencia (Spain), and Seoul (Korea), were compared to understand the factors behind often noted large SSA differences between them. SKYNET and AERONET algorithms are found to produce nearly same SSAs for similarity in input data, suggesting that SSA differences between them are primarily due to quality of input data due to different calibration and/or observation protocols as well as difference in quality assurance criteria. The most plausible reason for high SSAs in SKYNET is found to be underestimated calibration constant for sky radiance (ΔΩ). The disk scan method (scan area: 1° × 1° area of solar disk) of SKYNET is noted to produce stable wavelength-dependent ΔΩ values in comparison to those determined from the integrating sphere used by AERONET to calibrate sky radiance. Aerosol optical thickness (AOT) difference between them can be the next important factor for their SSA difference, if AOTs between them are not consistent. Inconsistent values of surface albedo while analyzing data of SKYNET and AERONET can also bring SSA difference between them, but the effect of surface albedo is secondary. The aerosol nonsphericity effect is found to be less important for SSA difference between these two networks.

  8. Dosimetric Factors Associated With Long-Term Dysphagia After Definitive Radiotherapy for Squamous Cell Carcinoma of the Head and Neck

    SciTech Connect

    Caudell, Jimmy J.; Schaner, Philip E.; Desmond, Renee A.; Meredith, Ruby F.; Spencer, Sharon A.; Bonner, James A.

    2010-02-01

    Purpose: Intensification of radiotherapy and chemotherapy for head-and-neck cancer may lead to increased rates of dysphagia. Dosimetric predictors of objective findings of long-term dysphagia were sought. Methods and Materials: From an institutional database, 83 patients were identified who underwent definitive intensity-modulated radiotherapy for squamous cell carcinoma of the head and neck, after exclusion of those who were treated for a second or recurrent head-and-neck primary lesion, had locoregional recurrence at any time, had less than 12 months of follow-up, or had postoperative radiotherapy. Dosimetric parameters were analyzed relative to three objective endpoints as a surrogate for severe long-term dysphagia: percutaneous endoscopic gastrostomy (PEG) tube dependence at 12 months, aspiration on modified barium swallow, or pharyngoesophageal stricture requiring dilation. Results: Mean dose greater than 41 Gy and volume receiving 60 Gy (V{sub 60}) greater than 24% to the larynx were significantly associated with PEG tube dependence and aspiration. V{sub 60} greater than 12% to the inferior pharyngeal constrictor was also significantly associated with increased PEG tube dependence and aspiration. V{sub 65} greater than 33% to the superior pharyngeal constrictor or greater than 75% to the middle pharyngeal constrictor was associated with pharyngoesophageal stricture requiring dilation. Conclusions: Doses to the larynx and pharyngeal constrictors predicted long-term swallowing complications, even when controlled for other clinical factors. The addition of these structures to intensity-modulated radiotherapy optimization may reduce the incidence of dysphagia, although cautious clinical validation is necessary.

  9. Scattering cross-section emission factors for visibility and radiative transfer applications: military vehicles traveling on unpaved roads.

    PubMed

    Moosmüller, Hans; Varma, Ravi; Arnott, W Patrick; Kuhns, Hampden D; Etyemezian, Vicken; Gillies, John A

    2005-11-01

    Emission factors for particulate matter (PM) are generally reported as mass emission factors (PM mass emitted per time or activity) as appropriate for air quality standards based on mass concentration. However, for visibility and radiative transfer applications, scattering, absorption, and extinction coefficients are the parameters of interest, with visibility standards based on extinction coefficients. These coefficients (dimension of inverse distance) equal cross-section concentrations, and, therefore, cross-section emission factors are appropriate. Scattering cross-section emission factors were determined for dust entrainment by nine vehicles, ranging from light passenger vehicles to heavy military vehicles, traveling on an unpaved road. Each vehicle made multiple passes at multiple speeds while scattering and absorption coefficients, wind velocity and dust plume profiles, and additional parameters were measured downwind of the road. Light absorption of the entrained PM was negligible, and the light extinction was primarily caused by scattering. The resulting scattering cross-section emission factors per vehicle kilometer traveled (vkt) range from 12.5 m2/vkt for a slow (16 km/ hr), light (1176 kg) vehicle to 3724 m2/vkt for a fast (64 km/hr), heavy (17,727 kg) vehicle and generally increase with vehicle speed and mass. The increase is approximately linear with speed, yielding emission factors per vkt and speed ranging from 4.2 m2/(vkt km/hr) to 53 m2/(vkt km/hr). These emission factors depend approximately linearly on vehicle mass within the groups of light (vehicle mass < or =3100 kg) and heavy (vehicle mass >8000 kg) vehicles yielding emission factors per vkt, speed, and mass of 0.0056 m2/(vkt km/hr kg) and 0.0024 m2/(vkt km/hr kg), respectively. Comparison of the scattering cross-section and PM mass emission factors yields average mass scattering efficiencies of 1.5 m2/g for the light vehicles and of 0.8 m2/g for the heavy vehicles indicating that the heavy

  10. Simulation of the shape of chaperonins using the small-angle x-ray scattering curves and torus form factor

    SciTech Connect

    Amarantov, S. V.; Naletova, I. N.; Kurochkina, L. P.

    2011-08-15

    The inverse scattering problem has been solved for protein complexes whose surfaces can be described by a set of the simplest doubly connected surfaces in the uniform approximation (a scattering potential inside the molecule is a constant). Solutions of two proteins-well-known GroEL bacterial chaperonin and poor-studied bacteriophage chaperonin, which is a product of 146 gene (gp146)-were taken for the experiment. The shapes of protein complexes have been efficiently reconstructed from the experimental scattering curves. The shell method, the method of the rotation of amino acid sequences with the use of the form factor of an amino acid, and the method of seeking the model parameters of a protein complex with the preliminarily obtained form factor of the model have been used to reconstruct the shape of these particles.

  11. Periodontal disease and mouthwash use are risk factors for head and neck squamous cell carcinoma

    PubMed Central

    Eliot, Melissa N.; Michaud, Dominique S.; Langevin, Scott M.; McClean, Michael D.; Kelsey, Karl T.

    2013-01-01

    Purpose The purpose of this study was to examine associations between oral hygiene, including history of periodontal disease and mouthwash use, and risk of head and neck squamous cell carcinoma (HNSCC). Methods We measured history of oral hygiene and dental care on 513 HNSCC cases and 567 controls from a population-based study of HNSCC. Logistic regression was used to estimate odds ratios (ORs) and 95% confidence intervals (95% CI). Results Periodontal disease was associated with a slightly elevated risk of HNSCC (OR = 1.09, 95% CI: 1.02, 1.16). Using any type of mouthwash at least once per day was associated with increased risk compared to never using mouthwash (OR = 1.11, 95% CI: 1.02, 1.20). HNSCC was associated with frequent use of nonalcoholic mouthwash compared to using any kind of mouthwash rarely or never (OR = 1.24, 95% CI: 1.05, 1.47). Conclusions Our results support an association between periodontal disease and HNSCC. Our data suggest that mouthwash use is associated with HNSCC, but we noted no difference between the effects of alcohol-containing and nonalcoholic mouthwashes. PMID:23568534

  12. Dysphagia in Head and Neck Cancer Patients: Pretreatment Evaluation, Predictive Factors, and Assessment during Radio-Chemotherapy, Recommendations

    PubMed Central

    Merlano, Marco C.; Russi, Elvio G.

    2013-01-01

    Progress in head and neck cancer (HNC) therapies has improved tumor response, loco-regional control, and survival. However, treatment intensification also increases early and late toxicities. Dysphagia is an underestimated symptom in HNC patients. Impairment of swallowing process could cause malnutrition, dehydration, aspiration, and pneumonia. A comprehensive literature review finalized in May 2012 included searches of electronic databases (Medline, Embase, and CAB abstracts) and scientific societies meetings materials (American Society of Clinical Oncology, Associazione Italiana Radioterapia Oncologica, Associazione Italiana di Oncologia Cervico-Cefalica, American Head and Neck Society, and European Society for Medical Oncology). Hand-searches of HNC journals and reference lists were carried out. Approximately one-third of dysphagia patients developed pneumonia requiring treatment. Aspiration pneumonia associated mortality ranged from 20% to 65%. Unidentified dysphagia caused significant morbidity, increased mortality, and decreased the quality of life. In this review we underline definition, causes, predictive factors of dysphagia and report on pretreatment and on-treatment evaluation, suggesting some key points to avoid underestimation. A multi-parameter assessment of swallowing problems may allow an earlier diagnosis. An appropriate evaluation might lead to a better treatment of both symptoms and cancer. PMID:24069513

  13. Heading and head injuries in soccer.

    PubMed

    Kirkendall, D T; Jordan, S E; Garrett, W E

    2001-01-01

    In the world of sports, soccer is unique because of the purposeful use of the unprotected head for controlling and advancing the ball. This skill obviously places the player at risk of head injury and the game does carry some risk. Head injury can be a result of contact of the head with another head (or other body parts), ground, goal post, other unknown objects or even the ball. Such impacts can lead to contusions, fractures, eye injuries, concussions or even, in rare cases, death. Coaches, players, parents and physicians are rightly concerned about the risk of head injury in soccer. Current research shows that selected soccer players have some degree of cognitive dysfunction. It is important to determine the reasons behind such deficits. Purposeful heading has been blamed, but a closer look at the studies that focus on heading has revealed methodological concerns that question the validity of blaming purposeful heading of the ball. The player's history and age (did they play when the ball was leather and could absorb significant amounts of water), alcohol intake, drug intake, learning disabilities, concussion definition and control group use/composition are all factors that cloud the ability to blame purposeful heading. What does seem clear is that a player's history of concussive episodes is a more likely explanation for cognitive deficits. While it is likely that the subconcussive impact of purposeful heading is a doubtful factor in the noted deficits, it is unknown whether multiple subconcussive impacts might have some lingering effects. In addition, it is unknown whether the noted deficits have any affect on daily life. Proper instruction in the technique is critical because if the ball contacts an unprepared head (as in accidental head-ball contacts), the potential for serious injury is possible. To further our understanding of the relationship of heading, head injury and cognitive deficits, we need to: learn more about the actual impact of a ball on the

  14. Conduct problems and level of social competence in Head Start children: prevalence, pervasiveness, and associated risk factors.

    PubMed

    Webster-Stratton, C; Hammond, M

    1998-06-01

    The purpose of the current project was to determine the prevalence of conduct problems, low social competence, and associated risk factors in a sample of 4-year-old low-income children (N = 426) from 64 Head Start classrooms in the Seattle area. Conduct problems and social competence were assessed based on a combination of teacher reports, parent reports, and independent observations of children interacting with peers in the classroom and with parents at home. We examined the relative contribution of a variety of risk factors, including maternal history and socioeconomic background, current levels of stress and social support, mothers' emotional state, and parenting competence in relation to "pervasive" (i.e., at home and school) and "nonpervasive" conduct problems and low social competence. Findings indicated similar risk factors for conduct problems and for low social competence, with an ordered increase in the number of risk factors from normal to "nonpervasive" to "pervasive" groups. Harshness of parenting style (i.e., slapping, hitting, yelling) significantly distinguished between the three groups for low social competence and conduct problems. Positive affect, praise, and physical warmth from mothers were positively related to social competence but unrelated to conduct problems. PMID:11324301

  15. Psychological Factors Associated with Head and Neck Cancer Treatment and Survivorship: Evidence and Opportunities for Behavioral Medicine

    PubMed Central

    Howren, M. Bryant; Christensen, Alan J.; Karnell, Lucy Hynds; Funk, Gerry F.

    2012-01-01

    Individuals diagnosed with head and neck cancer (HNC) face not only a potentially life-threatening diagnosis, but must endure treatment that often results in significant, highly visible disfigurement and disruptions of essential functioning, such as deficits or complications in eating, swallowing, breathing, and speech. Each year, approximately 650,000 new cases are diagnosed, making HNC the sixth most common type of cancer in the world. Despite this, however, HNC remains understudied in behavioral medicine. In this article, the authors review available evidence regarding several important psychosocial and behavioral factors associated with HNC diagnosis, treatment, and recovery, as well as various psychosocial interventions conducted in this patient population, before concluding with opportunities for behavioral medicine research and practice. PMID:22963591

  16. Covariant Spectator Theory of np scattering: Deuteron magnetic moment and form factors

    SciTech Connect

    Gross, Franz L.

    2014-06-01

    The deuteron magnetic moment is calculated using two model wave functions obtained from 2007 high precision fits to $np$ scattering data. Included in the calculation are a new class of isoscalar $np$ interaction currents which are automatically generated by the nuclear force model used in these fits. After normalizing the wave functions, nearly identical predictions are obtained: model WJC-1, with larger relativistic P-state components, gives 0.863(2), while model WJC-2 with very small $P$-state components gives 0.864(2) These are about 1\\% larger than the measured value of the moment, 0.857 n.m., giving a new prediction for the size of the $\\rho\\pi\\gamma$ exchange, and other purely transverse interaction currents that are largely unconstrained by the nuclear dynamics. The physical significance of these results is discussed, and general formulae for the deuteron form factors, expressed in terms of deuteron wave functions and a new class of interaction current wave functions, are given.

  17. Enhancement factor statistics of surface enhanced Raman scattering in multiscale heterostructures of nanoparticles.

    PubMed

    Zito, Gianluigi; Rusciano, Giulia; Sasso, Antonio

    2016-08-01

    Suitable metal nanostructures may induce surface-enhanced Raman scattering (SERS) enhancement factors (EFs) large-enough to reach single-molecule sensitivity. However, the gap hot-spot EF probability density function (PDF) has the character of a long-tail distribution, which dramatically mines the reproducibility of SERS experiments. Herein, we carry out electrodynamic calculations based on a 3D finite element method of two plasmonic nanostructures, combined with Monte Carlo simulations of the EF statistics under different external conditions. We compare the PDF produced by a homodimer of nanoparticles with that provided by a self-similar trimer. We show that the PDF is sensitive to the spatial distribution of near-field enhancement specifically supported by the nanostructure geometry. Breaking the symmetry of the plasmonic system is responsible for inducing particular modulations of the PDF tail resembling a multiple Poisson distribution. We also study the influence that molecular diffusion towards the hottest hot-spot, or selective hot-spot targeting, might have on the EF PDF. Our results quantitatively assess the possibility of designing the response of a SERS substrate so as to contain the intrinsic EF PDF variance and significantly improving, in principle, the reproducibility of SERS experiments. PMID:27497573

  18. Enhancement factor statistics of surface enhanced Raman scattering in multiscale heterostructures of nanoparticles

    NASA Astrophysics Data System (ADS)

    Zito, Gianluigi; Rusciano, Giulia; Sasso, Antonio

    2016-08-01

    Suitable metal nanostructures may induce surface-enhanced Raman scattering (SERS) enhancement factors (EFs) large-enough to reach single-molecule sensitivity. However, the gap hot-spot EF probability density function (PDF) has the character of a long-tail distribution, which dramatically mines the reproducibility of SERS experiments. Herein, we carry out electrodynamic calculations based on a 3D finite element method of two plasmonic nanostructures, combined with Monte Carlo simulations of the EF statistics under different external conditions. We compare the PDF produced by a homodimer of nanoparticles with that provided by a self-similar trimer. We show that the PDF is sensitive to the spatial distribution of near-field enhancement specifically supported by the nanostructure geometry. Breaking the symmetry of the plasmonic system is responsible for inducing particular modulations of the PDF tail resembling a multiple Poisson distribution. We also study the influence that molecular diffusion towards the hottest hot-spot, or selective hot-spot targeting, might have on the EF PDF. Our results quantitatively assess the possibility of designing the response of a SERS substrate so as to contain the intrinsic EF PDF variance and significantly improving, in principle, the reproducibility of SERS experiments.

  19. High triglyceride is a risk factor for silent osteonecrosis of the femoral head in systemic lupus erythematosus.

    PubMed

    Kuroda, Takeshi; Tanabe, Naohito; Wakamatsu, Ayako; Takai, Chinatsu; Sato, Hiroe; Nakatsue, Takeshi; Wada, Yoko; Nakano, Masaaki; Narita, Ichiei

    2015-12-01

    The purpose of this study was to clarify the factors related to silent osteonecrosis of the femoral head (ONFH) in patients with systemic lupus erythematosus (SLE). Seventy-eight patients with SLE were selected on the basis of having been newly diagnosed and requiring high-dose prednisolone, including pulse therapy with methylprednisolone, as the initial treatment. All the patients initially underwent MRI at 3 months after the start of corticosteroid treatment to detect any early changes in the femoral head. These examinations were then performed again 3 months later. Laboratory parameters were evaluated at the start of steroid treatment and at 1 month thereafter. By 3 months after the start of corticosteroid treatment, silent ONFH was diagnosed by MRI in 21 patients (26.9 %), being bilateral in 11 patients and unilateral in 10. The occurrence of silent ONFH was not related to SLE disease activity index, serological activity, or renal function; it was also unrelated to body mass index (BMI), body surface area (BSA), and the initial dose of prednisolone per unit body weight. However, the total cholesterol level at 4 weeks after the start of steroid treatment tended to be higher in patients with silent ONFH. Patients with a higher triglyceride level showed a significantly higher frequency of silent ONFH both before (p = 0.002) and 4 weeks after (p = 0.036) steroid initiation.A high triglyceride level is an important risk factor for silent ONFH in patients with SLE, and large-scale epidemiologic surveys of such early events are needed in this patient population. PMID:26384821

  20. Quality of life associated factors in head and neck cancer patients in a developing country using the FACT-H&N.

    PubMed

    Bilal, Sobia; Doss, Jennifer Geraldine; Cella, David; Rogers, Simon N

    2015-03-01

    Health-related quality of life (HRQoL) associated factors are vital considerations prior to treatment decision-making for head and neck cancer patients. The study aimed to identify potential socio-demographic and clinical prognostic value of HRQoL in head and neck cancer patients in a developing country. The Functional Assessment of Cancer Therapy-Head and Neck (FACT-H&N)-V4 in Urdu language was administered among 361 head and neck cancer patients. Data were statistically tested through multivariate analysis of variance (MANOVA) and regression modeling to identify the potentially associated factors. Treatment status, tumor stage and tumor site had the strongest negative impact on patients HRQoL, with a statistically significant decrement in FACT summary scales (effect size >0.15). Moderate associated factors of HRQoL included treatment type, marital status, employment status and age (effect size range 0.06-0.15). Weak associated factors of HRQoL with a small effect size (>0.01-0.06) included tumor size and type, gender, education level and ethnicity. This study reports 12 socio-demographic and clinical variables that have a significant impact on HRQoL of head, and neck cancer patients, and that should be considered during treatment decision-making by multidisciplinary teams and also in future HRQoL studies conducted in other developing countries. PMID:25555894

  1. Weak charge form factor and radius of 208Pb through parity violation in electron scattering

    DOE PAGESBeta

    Horowitz, C. J.; Ahmed, Z.; Jen, C. -M.; Rakhman, A.; Souder, P. A.; Dalton, M. M.; Liyanage, N.; Paschke, K. D.; Saenboonruang, K.; Silwal, R.; et al

    2012-03-26

    We use distorted wave electron scattering calculations to extract the weak charge form factor FW(more » $$\\bar{q}$$), the weak charge radius RW, and the point neutron radius Rn, of 208Pb from the PREX parity violating asymmetry measurement. The form factor is the Fourier transform of the weak charge density at the average momentum transfer $$\\bar{q}$$ = 0.475 fm-1. We find FW($$\\bar{q}$$) = 0.204 ± 0.028(exp) ± 0.001(model). We use the Helm model to infer the weak radius from FW($$\\bar{q}$$). We find RW = 5.826 ± 0.181(exp) ± 0.027(model) fm. Here the exp error includes PREX statistical and systematic errors, while the model error describes the uncertainty in RW from uncertainties in the surface thickness σ of the weak charge density. The weak radius is larger than the charge radius, implying a 'weak charge skin' where the surface region is relatively enriched in weak charges compared to (electromagnetic) charges. We extract the point neutron radius Rn = 5.751 ± 0.175 (exp) ± 0.026(model) ± 0.005(strange) fm, from RW. Here there is only a very small error (strange) from possible strange quark contributions. We find Rn to be slightly smaller than RW because of the nucleon's size. As a result, we find a neutron skin thickness of Rn-Rp = 0.302 ± 0.175 (exp) ± 0.026 (model) ± 0.005 (strange) fm, where Rp is the point proton radius.« less

  2. Parental Factors Correlated with Developmental Outcome in the Migrant Head Start Child.

    ERIC Educational Resources Information Center

    Siantz, Mary Lou de Leon; Smith, M. Shelton

    1994-01-01

    Examined parental factors correlated with developmental outcomes among 60 Mexican American migrant farmworker children. Found that maternal parenting style accounted for a significant amount of the variance in child behavior problems reported by the mothers, whereas maternal social support helped to explain the variance in peer acceptance reported…

  3. Is overexpression of TWIST, a transcriptional factor, a prognostic biomarker of head and neck carcinoma? Evidence from fifteen studies

    PubMed Central

    Zhuo, Xianlu; Luo, Huanli; Chang, Aoshuang; Li, Dairong; Zhao, Houyu; Zhou, Qi

    2015-01-01

    TWIST, a basic helix-loop-helix transcription factor, has been indicated to play a critical role in the progression of numerous malignant disorders. Published data on the significance of TWIST expression in head and neck carcinoma (HNC) risk have yielded conflicting results. Thus, we conducted a quantitative meta-analysis to obtain a precise estimate of this subject. After systematic searching and screening, a total of fifteen studies using immunohistochemistry for TWIST detection were included. The results showed that TWIST positive expression rate in HNC tissues was higher than that in normal tissues. TWIST expression might have a correlation with clinical features such as low differentiation, advanced clinical stage, presence of lymph node metastasis, distant metastasis and local recurrence (P < 0.05) , but not with age, gender, T stage and smoking as well as drinking (P > 0.05). In addition, over-expression of TWIST was a prognostic factor for HNC (HR = 1.92, 95% CI = 1.13–3.25). The data suggested that TWIST might play critical roles in cancer progression and act as a prognostic factor for HNC patients. PMID:26656856

  4. Lifestyle Factors in Cancer Survivorship: Where We Are and Where We Are Headed

    PubMed Central

    Vijayvergia, Namrata; Denlinger, Crystal S.

    2015-01-01

    Advances in early detection and curative therapies have led to an increased number of cancer survivors over the last twenty years. With this population comes the need to evaluate the late and long term effects of cancer treatment and develop recommendations about how to optimally care for these survivors. Lifestyle factors (diet, body weight, physical activity, and smoking) have been linked to a higher risk of many medical comorbidities (cardiovascular, metabolic, etc.). There is increasing evidence linking these factors to the risk of developing cancer and likely cancer-related outcomes. This link has been studied extensively in common cancers like breast, colon, prostate, and lung cancers through observational studies and is now being prospectively evaluated in interventional studies. Realizing that survivors are highly motivated to improve their overall health after a diagnosis of cancer, healthy lifestyle recommendations from oncology providers can serve as a strong tool to motivate survivors to adopt health behavior changes. Our article aims to review the evidence that links lifestyle factors to cancer outcomes and provides clinical recommendations for cancer survivors. PMID:26147495

  5. Investigation of static structure factor in dense suspensions by use of multiply scattered light.

    PubMed

    Shinde, R; Balgi, G; Richter, S; Banerjee, S; Reynolds, J; Pierce, J; Sevick-Muraca, E

    1999-01-01

    Near-infrared, frequency-domain photon migration measurements of phase shift are used to derive accurate values of isotropic scattering coefficients in concentrated, interacting suspensions of aqueous polystyrene microspheres with volume concentrations ranging from 1% to 45% by solids and mean diameters ranging from 135 to 500 nm. Under conditions of high ionic strength, the isotropic scattering coefficient can be quantitatively predicted by the Percus-Yevick model for hard-sphere interactions and Mie theory. In addition, the attractive interactions between scatterers arising from the addition of soluble poly(ethylene glycol) with molecular weights of 100 and 600 K cause hindered scattering. The increases in static structure and decreases in isotropic scattering coefficient agree with that predicted by Mie theory and the depletion interaction model developed by Asakura and Oosawa [J. Chem. Phys. 22, 1255 (1954)]. These results demonstrate the success of monitoring interaction between particles by use of multiple-scattered light and the necessity of incorporating models for these interactions when predicting scattering of dense, concentrated suspensions. PMID:18305603

  6. Ethnicity, location, age, and fluoridation factors in baby bottle tooth decay and caries prevalence of Head Start children.

    PubMed

    Barnes, G P; Parker, W A; Lyon, T C; Drum, M A; Coleman, G C

    1992-01-01

    Baby bottle tooth decay (BBTD) is a term applied to a specific form of rampant decay associated with inappropriate bottle or breast feeding of infants and young children. Although the prevalence of BBTD has been studied in individual ethnic groups, comparison studies are rare. Head Start children have frequently served as study subjects for assessing the prevalence of BBTD. The purpose of this study was to compare BBTD and caries prevalence among Head Start children who are members of four ethnic groups in five southwestern States. Age, residence, and fluoridation status were also compared for the total sample and ethnic categories. The sampling process was a stratified random site selection; it was used to obtain data on 1,230 children. This number constituted 3 percent of the children enrolled in Head Start in Public Health Service Region VI (Arkansas, Louisiana, New Mexico, Oklahoma, and Texas) where the study was conducted. The criterion for determining the presence of BBTD was based on the number of carious deciduous maxillary incisors observed. The severity of the condition was reported as two of four and three of four of the target teeth affected. Thus, two levels of severity are reported. BBTD was prevalent in approximately 24 percent and 15 percent of the total sample, depending on the severity criterion used. Native American children had a significantly higher (P less than 0.05) prevalence than Hispanic, white, and black subjects. Rural children had significantly higher (P less than 0.05) prevalence of BBTD than nonrural children for all ethnic groups except whites. The prevalence of decayed and filled (df) surfaces of primary dentition was significantly greater for all rural than for non rural groups (P< 0.05).Children attending centers showed no significant differences based on fluoride status for the total sample or other variables. BBTD and caries prevalence increased with age. Studies are needed to identify predisposing factors among the ethnic

  7. The Effect of Socioeconomic Factors on Quality of Life After Treatment in Patients With Head and Neck Cancer

    SciTech Connect

    Demiral, Ayse Nur Sen, Mehmet; Demiral, Yuecel; Kinay, Muenir

    2008-01-01

    Purpose: To determine the effect of socioeconomic factors on quality of life (QoL) after treatment in patients with head and neck carcinoma (HNC). Patients and Methods: The study population included 50 HNC patients seen in their control examinations after radiotherapy during a 2-month interval and who were willing to complete the Short-Form 36 QoL questionnaire. Socioeconomic, demographic, and tumor- and treatment-related factors were analyzed for their effect on physical component summary score (PCS) and mental component summary score (MCS) using the Mann-Whitney U test. Results: All patients received radiotherapy, and 33 patients (66%) underwent surgery for the primary tumor and/or neck disease. Chemotherapy was given in 9 patients (18%). Mean PCS and MCS were 47.9 (range, 24.8-59.3) and 46.7 (range, 22-63.3) for the whole patient population. There was no significant factor affecting PCS. Education level of 'middle school or higher,' perceived economic status of 'medium or higher,' social security status of not being 'absent or minimally covered,' and unilateral type of neck surgery were found to increase MCS significantly. According to separate linear regression analyses performed for three socioeconomic variables, the most significant factor for MCS was social security status compared with education level and perceived economic status. It was the only parameter that retained its significance when all five parameters were combined in a linear regression model. Conclusion: This study demonstrated that educational status, perceived economic status, and social security status showed a significant effect on the QoL of HNC patients after radiotherapy. When all variables were taken into account, only 'social security status' remained significant.

  8. Identification of chemoresistant factors by protein expression analysis with iTRAQ for head and neck carcinoma

    PubMed Central

    Nishimura, K; Tsuchiya, Y; Okamoto, H; Ijichi, K; Gosho, M; Fukayama, M; Yoshikawa, K; Ueda, H; Bradford, C R; Carey, T E; Ogawa, T

    2014-01-01

    Background: Cisplatin and other anticancer drugs are important in the treatment of head and neck squamous cell carcinoma; however, some tumours develop drug resistance. If chemoresistance could be determined before treatment, unnecessary drug administration would be avoided. Here, we investigated chemoresistance factors by comprehensive analyses at the protein level. Methods: Four human carcinoma cell lines were used: cisplatin-sensitive UM-SCC-23, UM-SCC-23-CDDPR with acquired cisplatin resistance, naturally cisplatin-resistant UM-SCC-81B, and UM-SCC-23/WR with acquired 5-fluorouracil resistance. Extracted proteins were labelled with iTRAQ and analysed by tandem mass spectrometry to identify resistance. Protein expression was confirmed by western blotting and functional analysis was carried out using siRNA. Results: Thirteen multiple-drug resistance proteins were identified, as well as seven proteins with specific resistance to cisplatin, including α-enolase. Differential expression of these proteins in cisplatin-resistant and -sensitive cell lines was confirmed by western blotting. Functional analysis for α-enolase by siRNA showed that cisplatin sensitivity significantly was increased in UM-SCC-81B and slightly in UM-SCC-23-CDDPR but not in UM-SCC-23/WR cells. Conclusions: We identified proteins thought to mediate anticancer drug resistance using recent proteome technology and identified α-enolase as a true cisplatin chemoresistance factor. Such proteins could be used as biomarkers for anticancer agent resistance and as targets of cancer therapy. PMID:25032734

  9. The Influence of Clinical and Demographic Risk Factors on the Establishment of Head and Neck Squamous Cell Carcinoma Cell Lines

    PubMed Central

    White, Jason S.; Weissfeld, Joel L.; Ragin, Camille C. R.; Rossie, Karen M.; Martin, Christa Lese; Shuster, Michele; Ishwad, Chandramohan S.; Law, John C.; Myers, Eugene N.; Johnson, Jonas T.; Gollin, Susanne M.

    2007-01-01

    The purpose of this study was to generate stable cell cultures from head and neck squamous cell carcinomas (HNSCC), and retrospectively analyze the factors associated with successful cell line establishment. Fifty-two HNSCC cell lines were isolated from a series of 199 tumors collected between 1992 and 1997 at the University of Pittsburgh Medical Center. Cell lines were characterized at the molecular and cellular level to determine the features associated with cell line formation. Successful cell line formation was dependent on multiple factors, including gene amplification involving chromosomal band 11q13, local and/or regional involvement of lymph nodes, and alcohol usage. The establishment of HNSCC cell lines enriches the resources available for cancer research. Our findings indicate that generation of stable cell lines from HNSCC is biased towards tumors with a poor prognosis. Our 52 stable lines comprise one of the largest series of HNSCC cell lines in the literature, with complete demographic, histopathologic, clinical, and survival data. PMID:17112776

  10. Crystal fields in YbInNi4 determined with magnetic form factor and inelastic neutron scattering

    NASA Astrophysics Data System (ADS)

    Severing, A.; Givord, F.; Boucherle, J.-X.; Willers, T.; Rotter, M.; Fisk, Z.; Bianchi, A.; Fernandez-Diaz, M. T.; Stunault, A.; Rainford, B. D.; Taylor, J.; Goremychkin, E.

    2011-04-01

    The magnetic form factor of YbInNi4 has been determined via the flipping ratios R with polarized neutron diffraction, and the scattering function S(Q,ω) was measured in an inelastic neutron scattering experiment. Both experiments were performed with the aim of determining the crystal-field scheme. The magnetic form factor clearly excludes the possibility of a Γ7 doublet as the ground state. The inelastic neutron data exhibit two almost equally strong peaks at 3.2 meV and 4.4 meV which points, in agreement with earlier neutron data, toward a Γ8 quartet ground state. Further possibilities such as a quasiquartet ground state are discussed.

  11. The prevalence of food insecurity and associated factors among households with children in Head Start programs in Houston, Texas and Birmingham, Alabama

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This study measured food security and hunger of households enrolled in Head Start in Houston, Texas, and Birmingham, Alabama and assessed factors that could affect food security. Interviewers collected data from primary caregivers on demographic characteristics, dietary intake, and the six-item US f...

  12. Ecological Contexts and Early Learning: Contributions of Child, Family, and Classroom Factors during Head Start, to Literacy and Mathematics Growth through First Grade

    ERIC Educational Resources Information Center

    Hindman, Annemarie H.; Skibbe, Lori E.; Miller, Alison; Zimmerman, Marc

    2010-01-01

    The current study investigated the extent to which child, family, and classroom factors during Head Start are related to children's literacy and mathematics skills at the beginning of preschool and through first grade. Children and families (n = 945) were participating in the Family and Child Experiences Survey (FACES), a large-scale data…

  13. TGF-β signaling deficient fibroblasts enhance Hepatocyte Growth Factor signaling in mammary carcinoma cells to promote scattering and invasion

    PubMed Central

    Cheng, Nikki; Chytil, Anna; Shyr, Yu; Joly, Alison; Moses, Harold L.

    2009-01-01

    Fibroblasts are major cellular components of the tumor microenvironment, regulating tumor cell behavior in part through secretion of extracellular matrix proteins, growth factors and angiogenic factors. In previous studies, conditional deletion of the type II TGF-β receptor in fibroblasts (Tgfbr2FspKO) was shown to promote mammary tumor metastasis in fibroblast: epithelial cell co-transplantation studies in mice, correlating with increased expression of HGF. Here, we advance our findings to show that Tgfbr2FspKO fibroblasts enhance HGF/c-Met and HGF/Ron signaling to promote scattering and invasion of mammary carcinoma cells. Blockade of c-Met and Ron by siRNA silencing and pharmacologic inhibitors significantly reduced mammary carcinoma cell scattering and invasion caused by Tgfbr2FspKO fibroblasts. Moreover, neutralizing antibodies to c-Met and Ron significantly inhibited HGF-induced cell scattering and invasion correlating with reduced Stat3 and p42/44MAPK phosphorylation. Investigation of the Stat3 and MAPK signaling pathways by pharmacologic inhibition and siRNA silencing revealed a cooperative interaction between the two pathways to regulate HGF- induced invasion, scattering and motility of mammary tumor cells. Furthermore, while c-Met was found to regulate both the Stat3 and MAPK signaling pathways, Ron was found to regulate Stat3, but not MAPK signaling in mammary carcinoma cells. These studies demonstrate a tumor suppressive role for TGF-β signaling in fibroblasts, in part by suppressing HGF signaling between mammary fibroblasts and epithelial cells. These studies characterize complex functional roles for HGF and TGF-β signaling in mediating tumor: stromal interactions during mammary tumor cell scattering and invasion, with important implications in the metastatic process. PMID:18922968

  14. Head circumference

    MedlinePlus

    ... a child's head circumference Normal ranges for a child's sex and age (weeks, months), based on values that experts have obtained for normal growth rates of infants' and children's heads Measurement of the head circumference is an ...

  15. Head Lice

    MedlinePlus

    Head lice are parasitic wingless insects. They live on people's heads and feed on their blood. An adult louse ... Children ages 3-11 and their families get head lice most often. Personal hygiene has nothing to ...

  16. Head Injuries

    MedlinePlus

    ... of head injuries include bicycle or motorcycle wrecks, sports injuries, falls from windows (especially among children who live ... to watch for? When can I start playing sports again after a head injury? How can brain damage from a head injury ...

  17. Head Lice

    MedlinePlus

    Head lice are parasitic wingless insects. They live on people's heads and feed on their blood. An adult ... Children ages 3-11 and their families get head lice most often. Personal hygiene has nothing to do ...

  18. Use of novel fibre-coupled radioluminescence and RADPOS dosimetry systems for total scatter factor measurements in small fields

    NASA Astrophysics Data System (ADS)

    Ploquin, N.; Kertzscher, G.; Vandervoort, E.; Cygler, J. E.; Andersen, C. E.; Francescon, P.

    2015-01-01

    A dosimetry system based on Al2O3:C radioluminescence (RL), and RADPOS, a novel 4D dosimetry system using microMOSFETs, were used to measure total scatter factors, ≤ft({{S}c,p}\\right)\\text{det}{{f\\text{clin}}}, for the CyberKnife robotic radiosugery system. New Monte Carlo calculated correction factors are presented and applied for the RL detector response for the 5, 7.5 and 10 mm collimators in order to correct for the detector geometry and increased photoelectric cross section of Al2O3:C relative to water. For comparison, measurements were also carried out using a micro MOSFET, PTW60012 diode and GAFCHROMIC® film (EBT and EBT2). Uncorrected ≤ft({{S}c,p}\\right)\\text{det}{{f\\text{clin}}}, were obtained by taking the ratio of the detector response for each collimator to that for the 60 mm diameter reference field. Published Monte Carlo calculated correction factors were applied to the RADPOS, microMOSFET and diode detector measurements to yield corrected field factors, Ω {{Q\\text{clin}},{{Q}\\text{msr}}}{{f\\text{clin}},{{f}\\text{msr}}}, following the terminology of a recent formalism introduced for small and composite field relative dosimetry. With corrections, the RL measured Ω {{Q\\text{clin}},{{Q}\\text{msr}}}{{f\\text{clin}},{{f}\\text{msr}}}, were 0.656  ±  0.002, 0.815  ±  0.002 and 0.865  ±  0.003 for the 5, 7.5 and 10 mm collimators, respectively. This was in good agreement with RADPOS corrected field factors of 0.650  ±  0.010, 0.816  ±  0.024 and 0.867  ±  0.010 for the 5, 7.5 and 10 mm collimators, respectively. Both RL and RADPOS total scatter factors agreed within approximately two standard deviations of the GAFCHROMIC film values (average of EBT and EBT2) of 0.640  ±  0.006, 0.806  ±  0.007 and 0.859  ±  0.09. Corrected total scatter factors for all dosimetry systems agreed within one standard deviation for collimator sizes 10-60 mm. Our study suggests that the micro

  19. Differential diagnostic value of computed tomography perfusion combined with vascular endothelial growth factor expression in head and neck lesions

    PubMed Central

    WANG, JIE; TANG, ZUOHUA; WANG, SHUYI; ZENG, WENJIAO; QIAN, WEN; WU, LINGJIE; WANG, WENZHONG; LUO, JIANFENG

    2016-01-01

    There are numerous types of head and neck lesions (HNLs), and conventional computed tomography (CT) has low specificity and sensitivity in the definitive and differential diagnosis of HNLs. The aim of the present study was to evaluate the value of perfusion CT (CTP) combined with vascular endothelial growth factor (VEGF) expression in the differentiation between malignant and benign HNLs. In total, 41 HNLs, which were pathologically confirmed, underwent CTP and VEGF expression analysis. All lesions were divided into three groups: Group A, benign hypovascular lesions; Group B, benign hypervascular lesions; and Group C, malignant lesions. Time density curve (TDC) and CTP parameters [maximum intensity projection (MIP), blood volume (BV), blood flow (BF), mean transit time and capillary permeability] were analyzed. The association between perfusion measurements and VEGF was assessed using Pearson's correlation. TDCs were classified into three types, and type I was more frequently identified in benign tumors (Groups A and B) compared with malignant tumors (Group C) (P=0.003). Malignant tumors primarily had a TDC of type II and III. MIP, BF and BV were all significantly higher in Groups B and C compared to Group A (P<0.01). VEGF expression of malignant tumors was significantly higher than benign tumors (P=0.007). No correlation was identified between VEGF and any CTP parameter. The present findings suggest that CTP combined with VEGF may differentiate between malignant and benign HNLs, and between benign hypovascular and hypervascular lesions. PMID:27123114

  20. Epidermal growth factor receptor variant III mediates head and neck cancer cell invasion via STAT3 activation

    PubMed Central

    Suzuki, Shinsuke; Morgan, Sarah E.; Thomas, Sufi M.; Sen, Malabika; Leeman-Neill, Rebecca J.; Kuan, Chien-Tsun; Bigner, Darrell; Gooding, William E.; Lai, Stephen Y.; Grandis, Jennifer R.

    2009-01-01

    Epidermal Growth Factor Receptor (EGFR) is frequently over-expressed in head and neck squamous cell carcinoma (HNSCC) where aberrant signaling downstream of this receptor contributes to tumor growth. EGFR variant III (EGFRvIII) is the most commonly altered form of EGFR and contains a truncated ligand-binding domain. We previously reported that EGFRvIII is expressed in up to 40% of HNSCC tumors where it is associated with increased proliferation, tumor growth and chemoresistance to anti-tumor drugs including the EGFR targeting monoclonal antibody cetuximab. Cetuximab was FDA-approved in 2006 for HNSCC but has not been shown to prevent invasion or metastasis. The present study was undertaken to evaluate the mechanisms of EGFRvIII-mediated cell motility and invasion in HNSCC. We found that EGFRvIII induced HNSCC cell migration and invasion in conjunction with increased STAT3 activation, which was not abrogated by cetuximab treatment. Further investigation demonstrated that EGF-induced expression of the STAT3 target gene HIF1-α, was abolished by cetuximab in HNSCC cells expressing wild-type EGFR under hypoxic conditions, but not in EGFRvIII-expressing HNSCC cells. These results suggest that EGFRvIII mediates HNSCC cell migration and invasion via increased STAT3 activation and induction of HIF1-α, which contribute to cetuximab resistance in EGFRvIII-expressing HNSCC tumors. PMID:20622897

  1. A Phenome-Based Functional Analysis of Transcription Factors in the Cereal Head Blight Fungus, Fusarium graminearum

    PubMed Central

    Min, Kyunghun; Park, Ae Ran; Lee, Jungkwan; Jin, Jian-Ming; Lin, Yang; Cao, Peijian; Hong, Sae-Yeon; Kim, Eun-Kyung; Lee, Seung-Ho; Cho, Aram; Lee, Seunghoon; Kim, Myung-Gu; Kim, Yongsoo; Kim, Jung-Eun; Kim, Jin-Cheol; Choi, Gyung Ja; Yun, Sung-Hwan; Lim, Jae Yun; Kim, Minkyun; Lee, Yong-Hwan; Choi, Yang-Do; Lee, Yin-Won

    2011-01-01

    Fusarium graminearum is an important plant pathogen that causes head blight of major cereal crops. The fungus produces mycotoxins that are harmful to animal and human. In this study, a systematic analysis of 17 phenotypes of the mutants in 657 Fusarium graminearum genes encoding putative transcription factors (TFs) resulted in a database of over 11,000 phenotypes (phenome). This database provides comprehensive insights into how this cereal pathogen of global significance regulates traits important for growth, development, stress response, pathogenesis, and toxin production and how transcriptional regulations of these traits are interconnected. In-depth analysis of TFs involved in sexual development revealed that mutations causing defects in perithecia development frequently affect multiple other phenotypes, and the TFs associated with sexual development tend to be highly conserved in the fungal kingdom. Besides providing many new insights into understanding the function of F. graminearum TFs, this mutant library and phenome will be a valuable resource for characterizing the gene expression network in this fungus and serve as a reference for studying how different fungi have evolved to control various cellular processes at the transcriptional level. PMID:22028654

  2. Epidermal growth factor-induced cyclooxygenase-2 enhances head and neck squamous cell carcinoma metastasis through fibronectin up-regulation

    PubMed Central

    Hsu, Jinn-Yuan; Chang, Kwang-Yu; Chen, Shang-Hung; Lee, Chung-Ta; Chang, Sheng-Tsung; Cheng, Hung-Chi; Chang, Wen-Chang; Chen, Ben-Kuen

    2015-01-01

    Epidermal growth factor receptor (EGFR) activation is a major cause of metastasis in many cancers, such as head and neck squamous cell carcinoma (HNSCC). However, whether the induction of cyclooxygenase-2 (COX-2) mediates EGF-enhanced HNSCC metastasis remains unclear. Interestingly, we found that EGF induced COX-2 expression mainly in HNSCC. The tumor cell transformation induced by EGF was repressed by COX-2 knockdown, and this repression was reversed by simultaneously treating the cells with EGF and prostaglandin E2 (PGE2). The down-regulation of COX-2 expression or inhibition of COX-2 activity significantly blocked EGF enhancement of cell migration and invasion, but the addition of PGE2 compensated for this inhibitory effect in COX-2-knockdown cells. COX-2 depletion inhibited EGF-induced matrix metalloproteinase (MMP)-1, MMP-2, MMP-3, MMP-9, and fibronectin expression and Rac1/cdc42 activation. The inhibitory effect of COX-2 depletion on MMPs and the fibronectin/Rac1/cdc42 axis were reversed by co-treatment with PGE2. Furthermore, depletion of fibronectin impeded the COX-2-enhanced binding of HNSCC cells to endothelial cells and tumor cells metastatic seeding of the lungs. These results demonstrate that EGF-induced COX-2 expression enhances HNSCC metastasis via activation of the fibronectin signaling pathway. The inhibition of COX-2 expression and activation may be a potential strategy for the treatment of EGFR-mediated HNSCC metastasis. PMID:25595899

  3. Predictive factors of head and neck squamous cell carcinoma patient tolerance to high-dose cisplatin in concurrent chemoradiotherapy

    PubMed Central

    NAKANO, KENJI; SATO, YASUYOSHI; TOSHIYASU, TAKASHI; SATO, YUKIKO; INAGAKI, LINA; TOMOMATSU, JUNICHI; SASAKI, TORU; SHIMBASHI, WATARU; FUKUSHIMA, HIROFUMI; YONEKAWA, HIROYUKI; MITANI, HIROKI; KAWABATA, KAZUYOSHI; TAKAHASHI, SHUNJI

    2016-01-01

    Although high-dose cisplatin is the standard regimen of concurrent chemoradiotherapy (CCRT) for locally advanced head and neck squamous cell carcinoma (HNSCC), varying levels of patient tolerance towards cisplatin have been reported, and the predictive factors of cisplatin tolerance remain to be elucidated. The present study retrospectively reviewed newly diagnosed HNSCC patients who received CCRT. Cisplatin (80 mg/m2) was administered every 3 weeks. The proportion of high-dose cisplatin-tolerant patients (cumulative cisplatin dose, ≥200 mg/m2) was determined, and the predictive factors of cisplatin tolerance were analyzed in a logistic regression analysis. Between June 2006 and March 2013, a total of 159 patients were treated with CCRT. The median follow-up time was 36.7 months. A total of 73 patients (46%) tolerated a cumulative cisplatin dose ≥200 mg/m2; male gender [odds ratio (OR), 25.00; P=0.005] and high body surface area (BSA) (>1.80 m2; OR, 2.21; P=0.032) were significantly predictive of high-dose cisplatin tolerance. The high-dose cisplatin-tolerant patients had a significantly higher complete response (CR) rate (82 vs. 67%, P=0.045); however, there were no significant between-group differences in the 3-year OS (79.5 vs. 81.2%, P=0.59) or PFS (70.4 vs. 44.6%, P=0.076) by cisplatin tolerance. In clinical practice, approximately one-half of the patients tolerated high-dose cisplatin in CCRT. Male gender and high BSA could be predictive of cisplatin tolerance. PMID:26893880

  4. Fast method of retrieving the asymmetry factor and scattering albedo from the maximum time-resolved reflectance of participating media.

    PubMed

    Qi, Hong; Ren, Ya-Tao; Chen, Qin; Ruan, Li-Ming

    2015-06-01

    This research presents a parametric study of the time-resolved hemispherical reflectance of a semi-infinite plane-parallel slab of homogeneous, nonemitting, absorbing, and anisotropic scattering medium exposed to a collimated Gaussian pulse. The one-dimensional transient radiative transfer equation was solved by using the finite volume method. The internal reflection at the medium-air interface caused by the mismatch of the refractive indices was considered. In particular, this work focused on the maximum diffuse hemispherical reflectance. Three different optical regions were identified according to the dimensionless pulsewidth βctp. The correlation between the normalized maximum hemispherical reflectance and βctp was conformed to the Boltzmann function. The coefficients in the correlating functions of the match and mismatch refractive index cases were fitted as polynomial fitting functions of the single scattering albedo ω and Henyey-Greenstein asymmetric factor g. Thus, ω and g can be simultaneously reconstructed by the semi-empirical correlations without solving the forward model. In conclusion, the proposed method can potentially retrieve the asymmetry factor and single scattering albedo of participating media accurately and efficiently. PMID:26192689

  5. Towards improved precision in the quantification of surface-enhanced Raman scattering (SERS) enhancement factors: a renewed approach.

    PubMed

    Sivanesan, Arumugam; Adamkiewicz, Witold; Kalaivani, Govindasamy; Kamińska, Agnieszka; Waluk, Jacek; Hołyst, Robert; Izake, Emad L

    2015-01-21

    This paper demonstrates a renewed procedure for the quantification of surface-enhanced Raman scattering (SERS) enhancement factors with improved precision. The principle of this method relies on deducting the resonance Raman scattering (RRS) contribution from surface-enhanced resonance Raman scattering (SERRS) to end up with the surface enhancement (SERS) effect alone. We employed 1,8,15,22-tetraaminophthalocyanato-cobalt(II) (4α-Co(II)TAPc), a resonance Raman- and electrochemically redox-active chromophore, as a probe molecule for RRS and SERRS experiments. The number of 4α-Co(II)TAPc molecules contributing to RRS and SERRS phenomena on plasmon inactive glassy carbon (GC) and plasmon active GC/Au surfaces, respectively, has been precisely estimated by cyclic voltammetry experiments. Furthermore, the SERS substrate enhancement factor (SSEF) quantified by our approach is compared with the traditionally employed methods. We also demonstrate that the present approach of SSEF quantification can be applied for any kind of different SERS substrates by choosing an appropriate laser line and probe molecule. PMID:25374971

  6. Experience of head and neck theatre staff and attitudes to human factors using an aviation-based analysis and classification system--a pilot survey.

    PubMed

    Konieczny, Katarzyna M; Seager, Leonie; Scott, Jim; Colbert, Serryth; Dale, Trevor; Brennan, Peter A

    2014-01-01

    The role that human factors have in contributing to air crashes is well known and is included as an essential part of training. Awareness of human factors in surgery is increasingly being recognised but surprisingly few papers have come from head and neck specialties. We circulated a questionnaire on human factors based on an aviation model to 140 head and neck medical and ancillary staff who work in operating theatres in 3 large UK hospitals. Most positive responses were found in the consultant group followed by trainee doctors and support staff. A significant difference was found in the subcategories of Unsafe Supervision (p=0.002) and Preconditions to Unsafe Acts (p=0.001). This work will help to identify multi-system deficiencies that can be corrected, and highlights aspects that may yield the greatest reduction in surgical errors. PMID:23643247

  7. Parity-Violating Electron Scattering from {sup 4}He and the Strange Electric Form Factor of the Nucleon

    SciTech Connect

    Aniol, K.A.; Margaziotis, D.J.; Armstrong, D.S.; Averett, T.; Finn, J.M.; Holmstrom, T.; Kelleher, A.; Moffit, B.; Sulkosky, V.; Benaoum, H.; Holmes, R.; Souder, P.A.; Bertin, P.Y.; Ferdi, C.

    2006-01-20

    We have measured the parity-violating electroweak asymmetry in the elastic scattering of polarized electrons from {sup 4}He at an average scattering angle <{theta}{sub lab}>=5.7 deg. and a four-momentum transfer Q{sup 2}=0.091 GeV{sup 2}. From these data, for the first time, the strange electric form factor of the nucleon G{sub E}{sup s} can be isolated. The measured asymmetry of A{sub PV}=(6.72{+-}0.84{sub (stat)}{+-}0.21{sub (syst)})x10{sup -6} yields a value of G{sub E}{sup s}=-0.038{+-}0.042{sub (stat)}{+-}0.010{sub (syst)}, consistent with zero.

  8. Meson exchange effects in elastic ep scattering at loop level and the electromagnetic form factors of the proton

    NASA Astrophysics Data System (ADS)

    Chen, Hong-Yu; Zhou, Hai-Qing

    2014-10-01

    A new form of two-photon exchange (TPE) effect is studied to explain the discrepancy between unpolarized and polarized experimental data in elastic ep scattering. The mechanism is based on a simple idea that apart from the usual TPE effects from box and crossed-box diagrams, the mesons may also be exchanged in elastic ep scattering by two-photon coupling at loop level. The detailed study shows such contributions to reduced unpolarized cross section (σun) and polarized observables (Pt,Pl) at fixed Q2 are only dependent on proton's electromagnetic form factors GE ,M and a new unknown universal parameter g. After combining this contribution with the usual TPE contributions from box and crossed-box diagrams, the ratio μpGE/GM extracted from the recent precise unpolarized and polarized experimental data can be described consistently.

  9. Search for optimal conditions for exploring double-parton scattering in four-jet production: kT -factorization approach

    NASA Astrophysics Data System (ADS)

    Kutak, Krzysztof; Maciuła, Rafał; Serino, Mirko; Szczurek, Antoni; van Hameren, Andreas

    2016-07-01

    In the present paper, we discuss how to maximize the double-parton scattering (DPS) contribution in four-jet production by selecting kinematical cuts. Here both single-parton and double-parton scattering effects are calculated in the kT -factorization approach, following our recent developments of relevant methods and tools. Several differential distributions are shown and discussed in the context of future searches for DPS effects, such as rapidity of jets, rapidity distance, and azimuthal correlations between jets. The dependence of the relative DPS amount is studied as a function of those observables. The regions with an enhanced DPS contribution are identified. Future experimental explorations could extract more precise values of σeff and its potential dependence on kinematical variables.

  10. Parity-Violating Electron Scattering from {sup 4}He and the Strange Electric Form Factor of the Nucleon

    SciTech Connect

    Aniol, Konrad; Armstrong, David; Averett, Todd; Benaoum, Hachemi; Bertin, Pierre; Burtin, Etienne; Cahoon, Jason; Cates, Gordon; Chang, C; Chao, Yu-Chiu; Chen, Jian-Ping; Choi, Seonho; Chudakov, Eugene; Craver, Brandon; Cusanno, Francesco; Decowski, Piotr; Deepa, Deepa; Ferdi, Catherine; Feuerbach, Robert; Finn, John; Frullani, Salvatore; Fuoti, Kirsten; Garibaldi, Franco; Gilman, Ronald; Glamazdin, Oleksandr; Gorbenko, V; Grames, Joseph; Hansknecht, John; Higinbotham, Douglas; Holmes, Richard; Holmstrom, Timothy; Humensky, Thomas; Ibrahim, Hassan; Jager, Cornelis De; Jiang, Xiaodong; Kaufman, Lisa; Kelleher, Aidan; Kolarkar, Ameya; Kowalski, Stanley; Kumar, Krishna; Lambert, Daniel; Laviolette, Peter; LeRose, John; Lhuillier, David; Liyanage, Nilanga; Margaziotis, Demetrius; Mazouz, Malek; McCormick, Kathy; Meekins, David; Meziani, Zein-Eddine; Michaels, Robert; Moffit, Bryan; Monaghan, Peter; Camacho, Carlos Munoz; Nanda, Sirish; Nelyubin, Vladimir; Neyret, Damien; Paschke, Kent; Poelker, Benard; Pomatsalyuk, Roman; Qiang, Yi; Reitz, Bodo; Roche, Julie; Saha, Arunava; Singh, Jaideep; Snyder, Ryan; Souder, Paul; Subedi, Ramesh; Suleiman, Riad; Sulkosky, Vincent; Tobias, William; Urciuoli, Guido; Vacheret, Antonin; Voutier, Eric; Wang, Kebin; Wilson, R; Wojtsekhowski, Bogdan; Zheng, Xiaochao

    2005-06-01

    We have measured the parity-violating electroweak asymmetry in the elastic scattering of polarized electrons from {sup 4}He at an average scattering angle {theta}{sub lab} = 5.7 degrees and a four-momentum transfer Q{sup 2} = 0.091 GeV{sup 2}. From these data, for the first time, the strange electric form factor of the nucleon G{sub E}{sup s} can be isolated. The measured asymmetry of A{sub PV} = 6.72 {+-} 0.84 (stat) {+-} 0.21 (syst) parts per million yields a value of G{sub E}{sup s} = -0.038 {+-} 0.042 (stat) {+-} 0.010 (syst), consistent with zero.

  11. Impact of boron-interstitial clusters on Hall scattering factor in high-dose boron-implanted ultrashallow junctions

    SciTech Connect

    Severac, Fabrice; Cristiano, Fuccio; Bedel-Pereira, Elena; Fazzini, Pier Francesco; Lerch, Wilfried; Paul, Silke; Hebras, Xavier; Giannazzo, Filippo

    2009-02-15

    The Hall scattering factor r{sub H} has been determined for holes in high-dose boron-implanted ultrashallow junctions containing high concentrations of boron-interstitial clusters (BICs), combining scanning capacitance microscopy, nanospreading resistance, Hall effect, and secondary ion mass spectroscopy measurements. A value of r{sub H}=0.74{+-}0.1 has been found in reference defect-free fully activated junctions, in good agreement with the existing literature. In the case of junctions containing high concentrations of immobile and electrically inactive BICs, and independently of the implant or the annealing process, the r{sub H} value has been found to be equal to 0.95{+-}0.1. The increase in the r{sub H} value is explained in terms of the additional scattering centers associated to the presence of high concentrations of BICs.

  12. Calculation of the Debye-Waller factor for atom-surface scattering: He on Ag(111)

    NASA Astrophysics Data System (ADS)

    Idiodi, J.; Bortolani, V.; Franchini, A.; Santoro, G.; Celli, V.

    1987-04-01

    By a consistent application of the distorted-wave Born approximation, the Debye-Waller exponent for the scattering of He atoms from the Ag(111) surface is directly computed. When diffraction is negligible, as in this case, the decrease in specular intensity is simply obtained by summing the scattering due to all possible one-phonon processes. Using one-phonon computed intensities that agree with experiment along high-symmetry directions of the surface Brillouin zone, we find that the computed Debye-Waller exponent agrees with experiment and corresponds to an effective Debye temperature of 241 K. All corrections to the eikonal-type formula, 2W=4p2z, are automatically included. In particular, the contribution of phonons with high parallel momentum is sharply cut off.

  13. Inelastic x-ray scattering studies on dynamic structure factor of polymeric liquid Se under pressure

    SciTech Connect

    Inui, Masanori; Kajihara, Yukio; Kimura, Koji; Matsuda, Kazuhiro; Ohara, Koji; Tsutsui, Satoshi; Ishikawa, Daisuke

    2015-08-17

    Inelastic X-ray scattering measurements at 25 MPa using synchrotron radiation were carried out for semiconducting liquid Se at high temperatures up to 1673 K. The excitation energy of the acoustic mode disperses approximately 10-50 % faster than the ultrasonic sound velocity in the observed temperature range while the ultrasonic sound rapidly slows down with increasing temperature. We carried out X-ray scattering measurements and found that the average coordination number at 1673 K is 1.3, indicating that the high temperature liquid consists of short chain molecules. These results suggest that weakening of the interatomic interaction is correlated with breaking of polymeric chain molecules.

  14. Two-Photon Exchange in Elastic Electron-Proton Scattering: A QCD Factorization Approach

    SciTech Connect

    Kivel, Nikolai; Vanderhaeghen, Marc

    2009-08-28

    We estimate the two-photon exchange contribution to elastic electron-proton scattering at large momentum transfer Q{sup 2}. It is shown that the leading two-photon exchange amplitude behaves as 1/Q{sup 4}, and can be expressed in a model independent way in terms of the leading twist nucleon distribution amplitudes. Using several models for the nucleon distribution amplitudes, we provide estimates for existing data and for ongoing experiments.

  15. Axl mediates acquired resistance of head and neck cancer cells to the epidermal growth factor receptor inhibitor erlotinib.

    PubMed

    Giles, Keith M; Kalinowski, Felicity C; Candy, Patrick A; Epis, Michael R; Zhang, Priscilla M; Redfern, Andrew D; Stuart, Lisa M; Goodall, Gregory J; Leedman, Peter J

    2013-11-01

    Elevated expression and activity of the epidermal growth factor receptor (EGFR) is associated with development and progression of head and neck cancer (HNC) and a poor prognosis. Clinical trials with EGFR tyrosine kinase inhibitors (e.g., erlotinib) have been disappointing in HNC. To investigate the mechanisms mediating resistance to these agents, we developed an HNC cell line (HN5-ER) with acquired erlotinib resistance. In contrast to parental HN5 HNC cells, HN5-ER cells exhibited an epithelial-mesenchymal (EMT) phenotype with increased migratory potential, reduced E-cadherin and epithelial-associated microRNAs (miRNA), and elevated vimentin expression. Phosphorylated receptor tyrosine kinase profiling identified Axl activation in HN5-ER cells. Growth and migration of HN5-ER cells were blocked with a specific Axl inhibitor, R428, and R428 resensitized HN5-ER cells to erlotinib. Microarray analysis of HN5-ER cells confirmed the EMT phenotype associated with acquired erlotinib resistance, and identified activation of gene expression associated with cell migration and inflammation pathways. Moreover, increased expression and secretion of interleukin (IL)-6 and IL-8 in HN5-ER cells suggested a role for inflammatory cytokine signaling in EMT and erlotinib resistance. Expression of the tumor suppressor miR-34a was reduced in HN5-ER cells and increasing its expression abrogated Axl expression and reversed erlotinib resistance. Finally, analysis of 302 HNC patients revealed that high tumor Axl mRNA expression was associated with poorer survival (HR = 1.66, P = 0.007). In summary, our results identify Axl as a key mediator of acquired erlotinib resistance in HNC and suggest that therapeutic inhibition of Axl by small molecule drugs or specific miRNAs might overcome anti-EGFR therapy resistance. PMID:24026012

  16. A Community-Based Oral Health Intervention in Navajo Nation Head Start: Participation Factors and Contextual Challenges.

    PubMed

    Bryant, Lucinda L; Quissell, David O; Braun, Patricia A; Henderson, William G; Johs, Nikolas; George, Carmen; Smith, Vong; Toledo, Nikola; Thomas, Jacob; Albino, Judith E

    2016-04-01

    Successful interventions require consistent participation by intended recipients. We utilized mixed methods to describe participation of 518 parent-child dyads enrolled in a randomized cluster trial of a 2-year oral health intervention for Head Start (HS) families across Navajo Nation delivered by native Community Oral Health Specialists (COHS). We quantitatively assessed factors that contributed to participation and qualitatively examined barriers and strategies. The intervention offered fluoride varnish (FV) and oral health promotion (OHP) activities for two cohorts (enrolled in 2011, N = 286, or 2012, N = 232) of children in the HS classrooms and OHP for parents outside the classroom. Child participation was good: FV: 79.7 (Cohort 1) and 85.3 % (Cohort 2) received at least 3 of 4 applications; OHP: 74.5 (Cohort 1) and 78.4 % (Cohort 2) attended at least 3 of 5 events. Parent participation was low: 10.5 (Cohort 1) and 29.8 % (Cohort 2) attended at least three of four events. Analysis of survey data found significant effects on parent participation from fewer people in the household, Cohort 2 membership, greater external-locus of control, and a greater perception that barriers existed to following recommended oral health behaviors. Qualitative analysis of reports from native field staff, COHS, community members, and the research team identified barriers (e.g., geographic expanse, constraints of a research trial) and suggested strategies to improve parent participation (e.g., improve communication between COHS and parents/community). Many challenges to participation exist when conducting interventions in rural areas with underserved populations. Working with community partners to inform the development and delivery of interventions is critical. PMID:26467679

  17. Cross-talk Between Estrogen Receptor and Epidermal Growth Factor Receptor in Head and Neck Squamous Cell Carcinoma

    PubMed Central

    Egloff, Ann Marie; Rothstein, Mary E.; Seethala, Raja; Siegfried, Jill M.; Grandis, Jennifer Rubin.; Stabile, Laura P.

    2009-01-01

    Purpose To characterize estrogen receptor (ER) expression and signaling in head and neck squamous cell carcinoma (HNSCC) cell lines and patient tissues and evaluate ER and epidermal growth factor (EGF) receptor (EGFR) cross-activation in HNSCC. Experimental Design ER expression and signaling in HNSCC cell lines were assessed by immunoblotting. In vitro proliferation and invasion were evaluated in HNSCC cell lines in response to ER and EGFR ligands or inhibitors. ER and EGFR protein expression in patient tissues was assessed by immunohistochemical (IHC) staining. Results Phospho-MAP kinase (P-MAPK) levels were significantly increased following combined estrogen (E2) and EGF treatment. Treatment of HNSCC cells with E2 and EGF significantly increased cell invasion compared to either treatment alone while inhibiting these two pathways resulted in reduced invasion compared to inhibiting either pathway alone. EGFR (P=0.008) and nuclear ERα (ERαnuc) (P<0.001) levels were significantly increased in HNSCC tumors (n=56) compared to adjacent mucosa (n=30) while ERβnuc levels did not differ (P=0.67). Patients with high ERαnuc and EGFR tumor levels had significantly reduced PFS compared to patients low tumor ERαnuc and EGFR levels (H.R. = 4.09, P = 0.01; Cox proportional hazards). In contrast, high ERβnuc tumor levels were not associated with reduced PFS alone or when combined with EGFR. Conclusions ERα and ERβ were expressed in HNSCC and stimulation with ER ligands resulted in both cytoplasmic signal transduction and transcriptional activation. ER and EGFR cross-talk was observed. Collectively, these studies indicate ER and EGFR together may contribute to HNSCC development and disease progression. PMID:19825947

  18. Characteristics of reproductive biology and proximate factors regulating seasonal breeding in captive golden-headed lion tamarins (Leontopithecus chrysomelas).

    PubMed

    De Vleeschouwer, Kristel; Leus, Kristin; Van Elsacker, Linda

    2003-08-01

    Reproduction is highly demanding in terms of energy expenditure, and the costs and benefits associated with postponing or investing in a reproductive effort are crucial determinants of an individual's fitness. Understanding the reproductive potential of a species under varying ecological conditions offers important insights into the dynamics of its social system. This study provides the first detailed analysis of the reproductive potential of wild- and captive-born golden-headed lion tamarins (Leontopithecus chrysomelas) under captive conditions, based on studbook data compiled during 1984-2000. Litters produced by wild-born females breeding in captivity are similar in size to litters observed in the wild, but smaller than litters of captive-born females. The more stringent ecological conditions experienced by wild-born females during maturation may result in a lifelong effect on litter size. However, interbirth intervals are shorter for wild-born than captive-born females. The relatively smaller burden of infant care that results from having smaller litters may allow wild-born females to sustain the next pregnancy sooner. Reproduction in the Brazilian captive population is highly seasonal for both wild-born females and females born in captivity in Brazil. Changes in photoperiod over a year provide a proximate explanation for changes in the proportion of conceptions and births per month. Outside Brazil, breeding occurs year-round, and no clear birth peak is apparent. Information from field reports that could be used to relate this finding to ecological factors, such as resource availability, is unavailable. PMID:12910464

  19. Identification of independent risk factors for flap failure: A retrospective analysis of 1530 free flaps for breast, head and neck and extremity reconstruction.

    PubMed

    Las, David E; de Jong, Tim; Zuidam, J Michiel; Verweij, Norbert M; Hovius, Steven E R; Mureau, Marc A M

    2016-07-01

    Reconstructive microsurgery is a powerful method of treating various complex defects. However, flap loss remains a possibility, leading to additional surgery, hospitalisation and costs. Consequently, it is important to know which factors lead to an increased risk of flap failure, so that measures can be undertaken to reduce this risk. Therefore, we analysed our results over a 20-year period to identify risk factors for flap failure after breast, head and neck and extremity reconstruction. The medical files of all patients treated between 1992 and 2012 were reviewed. Patient characteristics, surgical data and post-operative complications were scored, and independent risk factors for flap loss were identified. Reconstruction with a total of 1530 free flaps was performed in 1247 patients. Partial and total flap loss occurred in 5.5% and 4.4% of all free flaps, respectively. In all flaps, signs of compromised flap circulation were a risk factor for flap failure. More specifically, the risk factors for flap failure in breast reconstruction were previous radiotherapy, venous anastomosis revision, gluteal artery perforator (GAP) flap choice and post-operative bleeding. In head and neck reconstruction, pulmonary co-morbidity and anastomosis to the lingual vein or superficial temporal artery were risk factors, whereas a radial forearm flap reduced the risk. In extremity reconstruction, diabetes, prolonged anaesthesia time and post-operative wound infection were risk factors. Independent pre-, intra- and post-operative risk factors for flap failure after microvascular breast, head and neck and extremity reconstruction were identified. These results may be used to improve patient counselling and to adjust treatment algorithms to further reduce the chance of flap failure. PMID:26980600

  20. Production of two charm quark-antiquark pairs in single-parton scattering within the kt-factorization approach

    NASA Astrophysics Data System (ADS)

    van Hameren, Andreas; Maciuła, Rafał; Szczurek, Antoni

    2015-09-01

    We present first results for the 2 → 4 single-parton scattering gg → c c bar c c bar subprocess for the first time fully within the kt-factorization approach. In this calculation we have used the Kimber-Martin-Ryskin unintegrated gluon distribution which effectively includes some class of higher-order gluon emissions, and an off-shell matrix element squared calculated using recently developed techniques. The results are compared with our earlier result obtained within the collinear-factorization approach. Only slightly larger cross sections are obtained than in the case of the collinear approach. Inclusion of transverse momenta of gluons entering the hard process leads to a much stronger azimuthal decorrelation between cc and c bar c bar than in the collinear-factorization approach. A comparison to predictions of double parton scattering (DPS) results and the LHCb data strongly suggests that the assumption of two fully independent DPS (gg → c c bar ⊗ gg → c c bar) may be too approximate.

  1. DNA-Directed Assembly of Nanogold Dimers: A Unique Dynamic Light Scattering Sensing Probe for Transcription Factor Detection

    PubMed Central

    Seow, Nianjia; Tan, Yen Nee; Yung, Lin-Yue Lanry; Su, Xiaodi

    2015-01-01

    We have developed a unique DNA-assembled gold nanoparticles (AuNPs) dimer for dynamic light scattering (DLS) sensing of transcription factors, exemplified by estrogen receptor (ER) that binds specifically to a double-stranded (ds) DNA sequence containing estrogen response element (ERE). Here, ERE sequence is incorporated into the DNA linkers to bridge the AuNPs dimer for ER binding. Coupled with DLS, this AuNP dimer-based DLS detection system gave distinct readout of a single ‘complex peak’ in the presence of the target molecule (i.e., ER). This unique signature marked the first time that such nanostructures can be used to study transcription factor-DNA interactions, which DLS alone cannot do. This was also unlike previously reported AuNP-DLS assays that gave random and broad distribution of particles size upon target binding. In addition, the ERE-containing AuNP dimers could also suppress the light-scattering signal from the unbound proteins and other interfering factors (e.g., buffer background), and has potential for sensitive detection of target proteins in complex biological samples such as cell lysates. In short, the as-developed AuNP dimer probe coupled with DLS is a simple (mix and test), rapid (readout in ~5 min) and sensitive (low nM levels of ER) platform to detect sequence-specific protein-DNA binding event. PMID:26678946

  2. DNA-Directed Assembly of Nanogold Dimers: A Unique Dynamic Light Scattering Sensing Probe for Transcription Factor Detection

    NASA Astrophysics Data System (ADS)

    Seow, Nianjia; Tan, Yen Nee; Yung, Lin-Yue Lanry; Su, Xiaodi

    2015-12-01

    We have developed a unique DNA-assembled gold nanoparticles (AuNPs) dimer for dynamic light scattering (DLS) sensing of transcription factors, exemplified by estrogen receptor (ER) that binds specifically to a double-stranded (ds) DNA sequence containing estrogen response element (ERE). Here, ERE sequence is incorporated into the DNA linkers to bridge the AuNPs dimer for ER binding. Coupled with DLS, this AuNP dimer-based DLS detection system gave distinct readout of a single ‘complex peak’ in the presence of the target molecule (i.e., ER). This unique signature marked the first time that such nanostructures can be used to study transcription factor-DNA interactions, which DLS alone cannot do. This was also unlike previously reported AuNP-DLS assays that gave random and broad distribution of particles size upon target binding. In addition, the ERE-containing AuNP dimers could also suppress the light-scattering signal from the unbound proteins and other interfering factors (e.g., buffer background), and has potential for sensitive detection of target proteins in complex biological samples such as cell lysates. In short, the as-developed AuNP dimer probe coupled with DLS is a simple (mix and test), rapid (readout in ~5 min) and sensitive (low nM levels of ER) platform to detect sequence-specific protein-DNA binding event.

  3. Prevalence of Head Lice Infestation and Its Associated Factors among Primary School Students in Iran: A Systematic Review and Meta-analysis

    PubMed Central

    Moosazadeh, Mahmood; Afshari, Mahdi; Keianian, Hormoz; Nezammahalleh, Asghar; Enayati, Ahmad Ali

    2015-01-01

    Objectives Head lice infestation is one of the most important health problems, generally involving children aged 5–13 years. This study aims to estimate the prevalence of head lice infestation and its associated factors among primary school children using systematic review and meta-analysis methods. Methods Different national and international databases were searched for selecting the relevant studies using appropriate keywords, Medical Subject Heading terms, and references. Relevant studies with acceptable quality for meta-analysis were selected having excluded duplicate and irrelevant articles, quality assessment, and application of inclusion/exclusion criteria. With calculating standard errors according to binomial distribution and also considering the Cochrane's Q test as well as I-squared index for heterogeneity, pediculosis prevalence rate was estimated using Stata SE V.11 software. Results Forty studies met the inclusion criteria of this review and entered into the meta-analysis including 200,306 individuals. Using a random effect model, the prevalence (95% confidence interval) of head lice infestation among primary school children was estimated as 1.6% (1.2–2.05), 8.8% (7.6–9.9), and 7.4% (6.6–8.2) for boys, girls, and all the students, respectively. The infestation rate was found to be associated with low educational level of parents, long hair, family size, mother's job (housewife), father's job (worker/unemployed), using a common comb, lack of bathrooms in the house, and a low frequency of bathing. Conclusion This meta-analysis revealed that the prevalence of head lice infestation among Iranian primary school children is relatively high with more prevalence among girls. We also found that economic, social, cultural, behavioral, and hygienic factors are associated with this infestation. PMID:26835244

  4. Vascular endothelial growth factor/bone morphogenetic protein-2 bone marrow combined modification of the mesenchymal stem cells to repair the avascular necrosis of the femoral head

    PubMed Central

    Ma, Xiao-Wei; Cui, Da-Ping; Zhao, De-Wei

    2015-01-01

    Vascular endothelial cell growth factor (VEGF) combined with bone morphogenetic protein (BMP) was used to repair avascular necrosis of the femoral head, which can maintain the osteogenic phenotype of seed cells, and effectively secrete VEGF and BMP-2, and effectively promote blood vessel regeneration and contribute to formation and revascularization of tissue engineered bone tissues. To observe the therapeutic effect on the treatment of avascular necrosis of the femoral head by using bone marrow mesenchymal stem cells (BMSCs) modified by VEGF-165 and BMP-2 in vitro. The models were avascular necrosis of femoral head of rabbits on right leg. There groups were single core decompression group, core decompression + BMSCs group, core decompression + VEGF-165/BMP-2 transfect BMSCs group. Necrotic bone was cleared out under arthroscope. Arthroscopic observation demonstrated that necrotic bone was cleared out in each group, and fresh blood flowed out. Histomorphology determination showed that blood vessel number and new bone area in the repair region were significantly greater at various time points following transplantation in the core decompression + VEGF-165/BMP-2 transfect BMSCs group compared with single core decompression group and core decompression + BMSCs group (P < 0.05). These suggested that VEGF-165/BMP-2 gene transfection strengthened osteogenic effects of BMSCs, elevated number and quality of new bones and accelerated the repair of osteonecrosis of the femoral head. PMID:26629044

  5. Influence of electron-neutral collisions on the Compton scattering cross section and the Salpeter structure factor in warm collisional plasmas

    NASA Astrophysics Data System (ADS)

    Song, Mi-Young; Yoon, Jung-Sik; Jung, Young-Dae

    2015-03-01

    The electron-neutral collision effects on the Compton scattering process are investigated in warm collisional plasmas. The Compton scattering cross section in warm collisional plasmas is obtained by the Salpeter structure factor with the fluctuation-dissipation theorem and the plasma dielectric function as a function of the electron-neutral collision frequency, Debye length, and wave number. It is shown that the influence of electron-neutral collision strongly suppresses the Compton scattering cross section in warm collisional plasmas. It is also found that the electron-neutral collision effect on the differential Compton scattering cross section is more significant in forward scattering directions. We show that the differential Compton scattering cross section has a maximum at the scattering angle φ = π / 2 . In addition, we find that the electron-neutral collision effect on the total Compton scattering cross section increases with increasing Debye length and wave number. The variation of the Compton scattering cross section due to the change of collision frequency and plasma parameters is also discussed.

  6. Influence of electron-neutral collisions on the Compton scattering cross section and the Salpeter structure factor in warm collisional plasmas

    SciTech Connect

    Song, Mi-Young; Yoon, Jung-Sik; Jung, Young-Dae

    2015-03-15

    The electron-neutral collision effects on the Compton scattering process are investigated in warm collisional plasmas. The Compton scattering cross section in warm collisional plasmas is obtained by the Salpeter structure factor with the fluctuation-dissipation theorem and the plasma dielectric function as a function of the electron-neutral collision frequency, Debye length, and wave number. It is shown that the influence of electron-neutral collision strongly suppresses the Compton scattering cross section in warm collisional plasmas. It is also found that the electron-neutral collision effect on the differential Compton scattering cross section is more significant in forward scattering directions. We show that the differential Compton scattering cross section has a maximum at the scattering angle φ=π/2. In addition, we find that the electron-neutral collision effect on the total Compton scattering cross section increases with increasing Debye length and wave number. The variation of the Compton scattering cross section due to the change of collision frequency and plasma parameters is also discussed.

  7. Head Injuries

    MedlinePlus

    ... injuries internal head injuries, which may involve the skull, the blood vessels within the skull, or the brain Fortunately, most childhood falls or ... knock the brain into the side of the skull or tear blood vessels. Some internal head injuries ...

  8. Head Lice

    MedlinePlus

    ... or prescription products. Over-the-counter shampoos and lotions containing pyrethrin (one brand name: Rid) or permethrin ( ... commonly used to treat head lice. Shampoos and lotions that kill head lice contain pesticides and other ...

  9. Head MRI

    MedlinePlus

    ... the head; MRI - cranial; NMR - cranial; Cranial MRI; Brain MRI; MRI - brain; MRI - head ... tell your health care provider if you have: Brain aneurysm clips Certain types of artificial heart valves ...

  10. Magneto-transport in MoS2: phase coherence, spin-orbit scattering, and the hall factor.

    PubMed

    Neal, Adam T; Liu, Han; Gu, Jiangjiang; Ye, Peide D

    2013-08-27

    We have characterized phase coherence length, spin-orbit scattering length, and the Hall factor in n-type MoS2 2D crystals via weak localization measurements and Hall-effect measurements. Weak localization measurements reveal a phase coherence length of ~50 nm at T = 400 mK for a few-layer MoS2 film, decreasing as T(-1/2) with increased temperatures. Weak localization measurements also allow us, for the first time without optical techniques, to estimate the spin-orbit scattering length to be 430 nm, pointing to the potential of MoS2 for spintronics applications. Via Hall-effect measurements, we observe a low-temperature Hall mobility of 311 cm(2)/(V s) at T = 1 K, which decreases as a power law with a characteristic exponent γ = 1.5 from 10 to 60 K. At room temperature, we observe Hall mobility of 24 cm(2)/(V s). By determining the Hall factor for MoS2 to be 1.35 at T = 1 K and 2.4 at room temperature, we observe drift mobility of 420 and 56 cm(2)/(V s) at T = 1 K and room temperature, respectively. PMID:23889126

  11. Extensive small-angle X-ray scattering studies of blood coagulation factor VIIa reveal interdomain flexibility.

    PubMed

    Mosbaek, Charlotte Rode; Nolan, David; Persson, Egon; Svergun, Dmitri I; Bukrinsky, Jens Thostrup; Vestergaard, Bente

    2010-11-16

    Blood coagulation factor VIIa (FVIIa) is used in the treatment of replacement therapy resistant hemophilia patients, and FVIIa is normally activated upon complex formation with tissue factor (TF), potentially in context with structural rearrangements. The solution behavior of uncomplexed FVIIa is important for understanding the mechanism of activation and for the stability and activity of the pharmaceutical product. However, crystal structures of FVIIa in complex with TF and of truncated free FVIIa reveal different overall conformations while previous small-angle scattering studies suggest FVIIa always to be fully extended in solution. Here, small-angle X-ray scattering analysis of multiple forms of FVIIa and TF under several experimental conditions elaborate extensively on the understanding of the solution behavior of FVIIa. We reveal significant FVIIa domain flexibility in solution, whereas TF has a well-defined conformation. Unspecific formation of dimers of FVIIa is also observed and varies with experimental conditions. In particular, active site-inhibited FVIIa displays a distinct solution behavior different from that of uninhibited FVIIa, which may reflect structural rearrangements causing resistance to activation, thereby emphasizing the connection between the distribution of different conformations of FVII and the mechanism of activation. PMID:20873866

  12. New Measurement of Parity Violation in Elastic Electron-Proton Scattering and Implications for Strange Form Factors

    SciTech Connect

    Konrad Aniol; David Armstrong; Todd Averett; Maud Baylac; Etienne Burtin; John Calarco; Gordon Cates; Christian Cavata; Zhengwei Chai; C. Chang; Jian-Ping Chen; Eugene Chudakov; Evaristo Cisbani; Marius Coman; Daniel Dale; Alexandre Deur; Pibero Djawotho; Martin Epstein; Stephanie Escoffier; Lars Ewell; Nicolas Falletto; John Finn; A. Fleck; Bernard Frois; Salvatore Frullani; Juncai Gao; Franco Garibaldi; Ashot Gasparian; G. M. Gerstner; Ronald Gilman; Oleksandr Glamazdin; Javier Gomez; Viktor Gorbenko; Jens-ole Hansen; F. Hersman; Douglas Higinbotham; Richard Holmes; Maurik Holtrop; Thomas Humensky; Sebastien Incerti; Mauro Iodice; Cornelis De Jager; Johann Jardillier; Xiaodong Jiang; Mark Jones; J. Jorda; Christophe Jutier; W. Kahl; James Kelly; Donghee Kim; M. -J. Kim; Minsuk Kim; Ioannis Kominis; Edgar Kooijman; Kevin Kramer; Krishna Kumar; Michael Kuss; John LeRose; Raffaele De Leo; M. Leuschner; David Lhuillier; Meihua Liang; Nilanga Liyanage; R. Lourie; Richard Madey; Sergey Malov; Demetrius Margaziotis; Frederic Marie; Pete Markowitz; Jacques Martino; Peter Mastromarino; Kathy McCormick; Justin McIntyre; Zein-Eddine Meziani; Robert Michaels; Brian Milbrath; Gerald Miller; Joseph Mitchell; Ludyvine Morand; Damien Neyret; Gerassimos Petratos; Roman Pomatsalyuk; John Price; David Prout; Thierry Pussieux; Gilles Quemener; Ronald Ransome; David Relyea; Yves Roblin; Julie Roche; Gary Rutledge; Paul Rutt; Marat Rvachev; Franck Sabatie; Arunava Saha; Paul Souder; Marcus Spradlin; Steffen Strauch; Riad Suleiman; Jeffrey Templon; T. Teresawa; James Thompson; Raphael Tieulent; Luminita Todor; Baris Tonguc; Paul Ulmer; Guido Urciuoli; Branislav Vlahovic; Krishni Wijesooriya; R. Wilson; Bogdan Wojtsekhowski; Rhett Woo; Wang Xu; Imran Younus; C. Zhang

    2001-06-01

    We have measured the parity-violating electroweak asymmetry in the elastic scattering of polarized electrons from the proton. The result is A = -15.05 +- 0.98(stat) {+-} 0.56(syst) ppm at the kinematic point theta{sub lab} = 12.3 degrees and Q{sup 2} = 0.477 (GeV/c){sup 2}. The measurement implies that the value for the strange form factor (G{sub E}{sup s} + 0.392 G{sub M}{sup s})/(G{sub M}{sup p} {mu}{sub p}) = 0.069 +- 0.056 +- 0.039, where the first error is experimental and the second arises from the uncertainties in electromagnetic form factors. This measurement is the first fixed-target parity violation experiment that used either a ''strained'' GaAs photocathode to produce highly polarized electrons or a Compton polarimeter to continuously monitor the electron beam polarization.

  13. Optical constants and scattering factors from reflectivity measurements: 50 eV to 5 keV

    SciTech Connect

    Blake, R.L.; Davis, J.C.; Graessle, D.E.; Burbine, T.H.; Gullikson, E.M.

    1992-12-01

    An improved reflection technique has been introduced to permit more accurate measurements of material optical constants {delta} and {beta}, the density {rho}, and from these the atomic scattering factors f {prime} and f {double_prime}. Regions of normal and anomolous dispersion can be measured with resolving power 1000 or larger using a portable reflectometer that is moved to any of three beamlines at NSLS or two at CHESS. Herein the reflectometer and measurement techniques are described together with sample characteristics and preliminary results for the Ni LIII edge and the M edges of Au, Pt, and Ir. The primary accuracy limiting factors are density determination, accumulation of surface oxides or carbonaceous deposits, and synchrotron orbit stability. Each sample must be prepared for the specific energy range to be measured so that model fitting routines have the minimum possible number of free variables.

  14. Optical constants and scattering factors from reflectivity measurements: 50 eV to 5 keV

    SciTech Connect

    Blake, R.L.; Davis, J.C. ); Graessle, D.E.; Burbine, T.H. ); Gullikson, E.M. )

    1992-01-01

    An improved reflection technique has been introduced to permit more accurate measurements of material optical constants [delta] and [beta], the density [rho], and from these the atomic scattering factors f [prime] and f [double prime]. Regions of normal and anomolous dispersion can be measured with resolving power 1000 or larger using a portable reflectometer that is moved to any of three beamlines at NSLS or two at CHESS. Herein the reflectometer and measurement techniques are described together with sample characteristics and preliminary results for the Ni LIII edge and the M edges of Au, Pt, and Ir. The primary accuracy limiting factors are density determination, accumulation of surface oxides or carbonaceous deposits, and synchrotron orbit stability. Each sample must be prepared for the specific energy range to be measured so that model fitting routines have the minimum possible number of free variables.

  15. Surface-enhanced Raman scattering enhancement factor distribution for nanoparticles of arbitrary shapes using surface integral equation method

    NASA Astrophysics Data System (ADS)

    Ying Huang, Shao; Wu, Bae-Ian; Foong, Shaohui

    2013-01-01

    Poggio-Miller-Chang-Harrington-Wu-Tsai (PMCHWT) surface integral equation method is applied for the first time to accurately estimate the surface-enhanced Raman scattering (SERS) enhancement factor distribution for arbitrary nanoparticles and nano-aggregates. It is the first time in literature that the distributions of SERS enhancement factors of nanoparticles of a large variety are reported. It is shown that not every SERS substrate exhibits a long-tail distribution as a dimer consisting of two spheres in close proximity. Generic methods are proposed to evaluate the performance of nanoparticles on SERS substrates. A cumulative distribution is proposed to examine the contributions of hot and warm spots around the nanoparticles. It is used to identify the importance of warm spots on a SERS substrate. A parameter q is proposed to describe the likelihood of a randomly positioned molecule that can be activated. This study provides guidance and insights for the optimization of SERS substrate fabrication techniques.

  16. Head lice.

    PubMed

    Devore, Cynthia D; Schutze, Gordon E

    2015-05-01

    Head lice infestation is associated with limited morbidity but causes a high level of anxiety among parents of school-aged children. Since the 2010 clinical report on head lice was published by the American Academy of Pediatrics, newer medications have been approved for the treatment of head lice. This revised clinical report clarifies current diagnosis and treatment protocols and provides guidance for the management of children with head lice in the school setting. PMID:25917986

  17. The role of mental health factors and program engagement in the effectiveness of a preventive parenting program for Head Start mothers.

    PubMed

    Baydar, Nazli; Reid, M Jamila; Webster-Stratton, Carolyn

    2003-01-01

    Head Start centers were randomly assigned to intervention (parent training) or control conditions, and the role of maternal mental health risk factors on participation in and benefit from parent training was examined. Parenting was measured by parent report and independent observation in 3 domains: harsh/negative, supportive/positive, inconsistent/ineffective parenting. Structural equation modeling showed that parent engagement training was associated with improved parenting in a dose-response fashion. Mothers with mental health risk factors (i.e., depression, anger, history of abuse as a child, and substance abuse) exhibited poorer parenting than mothers without these risk factors. However, mothers with risk factors were engaged in and benefited from the parenting training program at levels that were comparable to mothers without these risk factors. PMID:14552407

  18. J. J. Sakurai Prize for Theoretical Particle Physics Talk: Hard scattering factorization in QCD

    NASA Astrophysics Data System (ADS)

    Collins, John

    2009-05-01

    Many important cross sections in high-energy collisions are analyzed using factorization properties. I review the nature of factorization, how it arose from the parton model, and current issues in its development. This talk will be coordinated with the one by Soper.

  19. Psychological Factors Associated with Head and Neck Cancer Treatment and Survivorship : Evidence and Opportunities for Behavioral Medicine

    ERIC Educational Resources Information Center

    Howren, M. Bryant; Christensen, Alan J.; Karnell, Lucy Hynds; Funk, Gerry F.

    2013-01-01

    Individuals diagnosed with head and neck cancer (HNC) not only face a potentially life-threatening diagnosis but must endure treatment that often results in significant, highly visible disfigurement and disruptions of essential functioning, such as deficits or complications in eating, swallowing, breathing, and speech. Each year, approximately…

  20. Head erosion with emittance growth in PWFA

    SciTech Connect

    Li, S. Z.; Adli, E.; England, R. J.; Frederico, J.; Gessner, S. J.; Hogan, M. J.; Litos, M. D.; Walz, D. R.; Muggli, P.; An, W.; Clayton, C. E.; Joshi, C.; Lu, W.; Marsh, K. A.; Mori, W.; Vafaei, N.

    2012-12-21

    Head erosion is one of the limiting factors in plasma wakefield acceleration (PWFA). We present a study of head erosion with emittance growth in field-ionized plasma from the PWFA experiments performed at the FACET user facility at SLAC. At FACET, a 20.3 GeV bunch with 1.8 Multiplication-Sign 10{sup 10} electrons is optimized in beam transverse size and combined with a high density lithium plasma for beam-driven plasma wakefield acceleration experiments. A target foil is inserted upstream of the plasma source to increase the bunch emittance through multiple scattering. Its effect on beamplasma interaction is observed with an energy spectrometer after a vertical bend magnet. Results from the first experiments show that increasing the emittance has suppressed vapor field-ionization and plasma wakefields excitation. Plans for the future are presented.

  1. Determination of the scattering coefficient of biological tissue considering the wavelength and absorption dependence of the anisotropy factor

    NASA Astrophysics Data System (ADS)

    Fukutomi, Daichi; Ishii, Katsunori; Awazu, Kunio

    2016-04-01

    The anisotropy factor g, one of the optical properties of biological tissues, has a strong influence on the calculation of the scattering coefficient μ s in inverse Monte Carlo (iMC) simulations. It has been reported that g has the wavelength and absorption dependence; however, few attempts have been made to calculate μ s using g values by taking the wavelength and absorption dependence into account. In this study, the angular distributions of scattered light for biological tissue phantoms containing hemoglobin as a light absorber were measured by a goniometric optical setup at strongly (405 nm) and weakly (664 nm) absorbing wavelengths to obtain g. Subsequently, the optical properties were calculated with the measured values of g by integrating sphere measurements and an iMC simulation, and compared with the results obtained with a conventional g value of 0.9. The μ s values with measured g were overestimated at the strongly absorbing wavelength, but underestimated at the weakly absorbing wavelength if 0.9 was used in the iMC simulation.

  2. Determination of scattering coefficient considering wavelength and absorption dependence of anisotropy factor measured by polarized beam for biological tissues

    NASA Astrophysics Data System (ADS)

    Fukutomi, D.; Ishii, K.; Awazu, K.

    2015-12-01

    Anisotropy factor g, one of the optical properties of biological tissues, is the most important parameter to accurately determine scattering coefficient μs in the inverse Monte Carlo (iMC) simulation. It has been reported that g has wavelength and absorption dependence, however, there are few attempts in order to calculate μs of biological tissue considering the wavelength and absorption dependence of g. In this study, the scattering angular distributions of biological tissue phantoms were measured in order to determine g by using goniometric measurements with three polarization conditions at strongly and weakly absorbing wavelengths of hemoglobin. Then, optical properties, especially, μs were measured by integrating sphere measurements and iMC simulation in order to confirm the influence of measured g on optical properties in comparison of with general value of g (0.9) for soft biological tissue. Consequently, it was found that μs was overestimated at strongly absorbing wavelength, however, μs was underestimated at weakly absorbing wavelength if the g was not considered its wavelength and absorption dependence.

  3. Risk factors for head and neck cancer in young adults: a pooled analysis in the INHANCE consortium

    PubMed Central

    Toporcov, Tatiana Natasha; Znaor, Ariana; Zhang, Zuo-Feng; Yu, Guo-Pei; Winn, Deborah M; Wei, Qingyi; Vilensky, Marta; Vaughan, Thomas; Thomson, Peter; Talamini, Renato; Szeszenia-Dabrowska, Neonila; Sturgis, Erich M; Smith, Elaine; Shangina, Oxana; Schwartz, Stephen M; Schantz, Stimson; Rudnai, Peter; Richiardi, Lorenzo; Ramroth, Heribert; Purdue, Mark P; Olshan, Andrew F; Eluf-Neto, José; Muscat, Joshua; Moyses, Raquel Ajub; Morgenstern, Hal; Menezes, Ana; McClean, Michael; Matsuo, Keitaro; Mates, Dana; Macfarlane, Tatiana V; Lissowska, Jolanta; Levi, Fabio; Lazarus, Philip; Vecchia, Carlo La; Lagiou, Pagona; Koifman, Sergio; Kjaerheim, Kristina; Kelsey, Karl; Holcatova, Ivana; Herrero, Rolando; Healy, Claire; Hayes, Richard B; Franceschi, Silvia; Fernandez, Leticia; Fabianova, Eleonora; Daudt, Alexander W; Curioni, Otávio Alberto; Maso, Luigino Dal; Curado, Maria Paula; Conway, David I; Chen, Chu; Castellsague, Xavier; Canova, Cristina; Cadoni, Gabriella; Brennan, Paul; Boccia, Stefania; Antunes, José Leopoldo Ferreira; Ahrens, Wolfgang; Agudo, Antonio; Boffetta, Paolo; Hashibe, Mia; Lee, Yuan-Chin Amy; Filho, Victor Wünsch

    2015-01-01

    Background: Increasing incidence of head and neck cancer (HNC) in young adults has been reported. We aimed to compare the role of major risk factors and family history of cancer in HNC in young adults and older patients. Methods: We pooled data from 25 case-control studies and conducted separate analyses for adults ≤45 years old (‘young adults’, 2010 cases and 4042 controls) and >45 years old (‘older adults’, 17 700 cases and 22 704 controls). Using logistic regression with studies treated as random effects, we estimated adjusted odds ratios (ORs) and 95% confidence intervals (CIs). Results: The young group of cases had a higher proportion of oral tongue cancer (16.0% in women; 11.0% in men) and unspecified oral cavity / oropharynx cancer (16.2%; 11.1%) and a lower proportion of larynx cancer (12.1%; 16.6%) than older adult cases. The proportions of never smokers or never drinkers among female cases were higher than among male cases in both age groups. Positive associations with HNC and duration or pack-years of smoking and drinking were similar across age groups. However, the attributable fractions (AFs) for smoking and drinking were lower in young when compared with older adults (AFs for smoking in young women, older women, young men and older men, respectively, = 19.9% (95% CI = 9.8%, 27.9%), 48.9% (46.6%, 50.8%), 46.2% (38.5%, 52.5%), 64.3% (62.2%, 66.4%); AFs for drinking = 5.3% (−11.2%, 18.0%), 20.0% (14.5%, 25.0%), 21.5% (5.0%, 34.9%) and 50.4% (46.1%, 54.3%). A family history of early-onset cancer was associated with HNC risk in the young [OR = 2.27 (95% CI = 1.26, 4.10)], but not in the older adults [OR = 1.10 (0.91, 1.31)]. The attributable fraction for family history of early-onset cancer was 23.2% (8.60% to 31.4%) in young compared with 2.20% (−2.41%, 5.80%) in older adults. Conclusions: Differences in HNC aetiology according to age group may exist. The lower AF of cigarette smoking and alcohol drinking in young

  4. Nanoparticle Properties and Synthesis Effects on Surface-Enhanced Raman Scattering Enhancement Factor: An Introduction

    PubMed Central

    2015-01-01

    Raman spectroscopy has enabled researchers to map the specific chemical makeup of surfaces, solutions, and even cells. However, the inherent insensitivity of the technique makes it difficult to use and statistically complicated. When Raman active molecules are near gold or silver nanoparticles, the Raman intensity is significantly amplified. This phenomenon is referred to as surface-enhanced Raman spectroscopy (SERS). The extent of SERS enhancement is due to a variety of factors such as nanoparticle size, shape, material, and configuration. The choice of Raman reporters and protective coatings will also influence SERS enhancement. This review provides an introduction to how these factors influence signal enhancement and how to optimize them during synthesis of SERS nanoparticles. PMID:25884017

  5. Anthropogenic Factors Are the Major Cause of Hospital Admission of a Threatened Species, the Grey-Headed Flying Fox (Pteropus poliocephalus), in Victoria, Australia.

    PubMed

    Scheelings, Titus Franciscus; Frith, Sarah Elizabeth

    2015-01-01

    To determine the reasons for presentation and outcomes of hospitalised grey-headed flying foxes (Pteropus poliocephalus) in Victoria, Australia, a retrospective analysis was performed on 532 records from two wildlife hospitals. Cases were categorised based on presenting signs and outcomes determined. Anthropogenic factors (63.7%) were a major cause of flying fox admissions with entanglement in fruit netting the most significant risk for bats (36.8%). Overall the mortality rate for flying fox admissions was 59.3%. This study highlights the effects of urbanisation on wild animal populations and a need for continued public education in order to reduce morbidity and mortality of wildlife, especially threatened species. PMID:26207984

  6. Anthropogenic Factors Are the Major Cause of Hospital Admission of a Threatened Species, the Grey-Headed Flying Fox (Pteropus poliocephalus), in Victoria, Australia

    PubMed Central

    Scheelings, Titus Franciscus; Frith, Sarah Elizabeth

    2015-01-01

    To determine the reasons for presentation and outcomes of hospitalised grey-headed flying foxes (Pteropus poliocephalus) in Victoria, Australia, a retrospective analysis was performed on 532 records from two wildlife hospitals. Cases were categorised based on presenting signs and outcomes determined. Anthropogenic factors (63.7%) were a major cause of flying fox admissions with entanglement in fruit netting the most significant risk for bats (36.8%). Overall the mortality rate for flying fox admissions was 59.3%. This study highlights the effects of urbanisation on wild animal populations and a need for continued public education in order to reduce morbidity and mortality of wildlife, especially threatened species. PMID:26207984

  7. Head lice.

    PubMed

    Frankowski, Barbara L; Bocchini, Joseph A

    2010-08-01

    Head lice infestation is associated with limited morbidity but causes a high level of anxiety among parents of school-aged children. Since the 2002 clinical report on head lice was published by the American Academy of Pediatrics, patterns of resistance to products available over-the-counter and by prescription have changed, and additional mechanical means of removing head lice have been explored. This revised clinical report clarifies current diagnosis and treatment protocols and provides guidance for the management of children with head lice in the school setting. PMID:20660553

  8. Prevalence of Clinical Anxiety, Clinical Depression and Associated Risk Factors in Chinese Young and Middle-Aged Patients with Osteonecrosis of the Femoral Head

    PubMed Central

    Gao, You-Shui; He, Hai-Yan; Jin, Dong-Xu; Zhang, Chang-Qing

    2015-01-01

    Objective To investigate the prevalence of clinical anxiety and clinical depression in Chinese young and mid-aged patients with osteonecrosis of the femoral head (ONFH) and to analyze their potential risk factors. Methods Two hundred and sixteen Chinese patients with ONFH were consecutively enrolled in this cross-sectional study from January 2010 to December 2010. The Zung self-rating anxiety scale (SAS) and the Zung self-rating depression scale (SDS) were used to assess the prevalence of clinical anxiety and clinical depression. An additional questionnaire containing seventeen items of potential risk factors was completed by all patients. Binary logistic regression analysis was employed to reveal potential risk factors of anxiety and depression. Results The prevalence of clinical anxiety and clinical depression was 20.4% and 21.8% in Chinese young and middle-aged patients with ONFH, respectively. Binary regression analysis showed that independent risk factors correlated with high incidence of clinical anxiety included involved femoral head (OR = 3.168, 95% CI: 1.496 - 6.708) and stages of ONFH (ORIV-V / II = 5.383, 95% CI: 1.664-17.416). Independent risk factors correlated with high incidence of depression included gender (OR = 2.853, 95% CI: 1.467-5.778), comorbid diseases (OR = 4.243, 95% CI: 1.940-9.278) and stages of the disease (OR IV-V/II = 16.963, 95% CI: 4.404-65.331). Conclusions Patients with bilateral ONFH are inclined to have clinical anxiety, while female patients and patients with comorbid diseases might tend to get clinical depression. Advanced stages of ONFH are independent risk factors for both clinical anxiety and clinical depression. PMID:25789850

  9. Refining Measurement of Social Cognitive Theory Factors Associated with Exercise Adherence in Head and Neck Cancer Patients.

    PubMed

    Rogers, Laura Q; Fogleman, Amanda; Verhulst, Steven; Bhugra, Mudita; Rao, Krishna; Malone, James; Robbs, Randall; Robbins, K Thomas

    2015-01-01

    Social cognitive theory (SCT) measures related to exercise adherence in head and neck cancer (HNCa) patients were developed. Enrolling 101 HNCa patients, psychometric properties and associations with exercise behavior were examined for barriers self-efficacy, perceived barriers interference, outcome expectations, enjoyment, and goal setting. Cronbach's alpha ranged from.84 to.95; only enjoyment demonstrated limited test-retest reliability. Subscales for barriers self-efficacy (motivational, physical health) and barriers interference (motivational, physical health, time, environment) were identified. Multiple SCT constructs were cross-sectional correlates and prospective predictors of exercise behavior. These measures can improve the application of the SCT to exercise adherence in HNCa patients. PMID:26177345

  10. A 3D point-kernel multiple scatter model for parallel-beam SPECT based on a gamma-ray buildup factor

    NASA Astrophysics Data System (ADS)

    Marinkovic, Predrag; Ilic, Radovan; Spaic, Rajko

    2007-09-01

    A three-dimensional (3D) point-kernel multiple scatter model for point spread function (PSF) determination in parallel-beam single-photon emission computed tomography (SPECT), based on a dose gamma-ray buildup factor, is proposed. This model embraces nonuniform attenuation in a voxelized object of imaging (patient body) and multiple scattering that is treated as in the point-kernel integration gamma-ray shielding problems. First-order Compton scattering is done by means of the Klein-Nishina formula, but the multiple scattering is accounted for by making use of a dose buildup factor. An asset of the present model is the possibility of generating a complete two-dimensional (2D) PSF that can be used for 3D SPECT reconstruction by means of iterative algorithms. The proposed model is convenient in those situations where more exact techniques are not economical. For the proposed model's testing purpose calculations (for the point source in a nonuniform scattering object for parallel beam collimator geometry), the multiple-order scatter PSF generated by means of the proposed model matched well with those using Monte Carlo (MC) simulations. Discrepancies are observed only at the exponential tails mostly due to the high statistic uncertainty of MC simulations in this area, but not because of the inappropriateness of the model.

  11. Light scattering by a rough surface of human skin. 1. The luminance factor of reflected light

    SciTech Connect

    Barun, V V; Ivanov, A P

    2013-08-31

    Based on the analytical solution of Maxwell's equations, we have studied the angular structure of the luminance factor of light reflected by the rough skin surface with large-scale relief elements, illuminated by a directed radiation beam incident at an arbitrary angle inside or outside the medium. The parameters of the surface inhomogeneities are typical of human skin. The calculated angular dependences are interpreted from the point of view of the angular distribution function of micro areas. The results obtained can be used for solving direct and inverse problems in biomedical optics, in particular for determining the depth of light penetration into a biological tissue, for studying the light action spectra on tissue chromophores under the in vivo conditions, for developing diagnostic methods of structural and biophysical parameters of a medium, and for optimising the mechanisms of interaction of light with biological tissues under their noninvasive irradiation through skin. (biomedical optics)

  12. Lifetime Prevalence and Factors Associated with Head Injury among Older People in Low and Middle Income Countries: A 10/66 Study

    PubMed Central

    Khan, A.; Prince, M.; Brayne, C.; Prina, A. M.

    2015-01-01

    Introduction Traumatic brain injury (TBI) is a growing public health problem around the world, yet there is little information on the prevalence of head injury in low and middle income countries (LMICs). We utilised data collected by the 10/66 research group to investigate the lifetime prevalence of head injury in defined sites in low and middle income countries, its risk factors and its relationship with disability. Methods We analysed data from one-phase cross-sectional surveys of all residents aged 65 years and older (n = 16430) distributed across twelve sites in eight low and middle income countries (China, Cuba, Dominican Republic, India, Venezuela, Mexico, Peru, and Puerto Rico). Self-reported cases of head injury with loss of consciousness were identified during the interview. A sensitivity analysis including data provided by informants of people with dementia was also used to estimate the impact of this information on the estimates. Prevalence ratios (PR) from Poisson regressions were used to identify associated risk factors. Results The standardised lifetime prevalence of TBI ranged from 0.3% in China to 14.6% in rural Mexico and Venezuela. Being male (PR: 1.6, 95% CI: 1.29–1.82), younger (PR: 0.95, 95% CI: 0.92–0.99), with lower education (PR 0.91, 95% CI: 0.86–0.96), and having fewer assets (PR 0.92, 95% CI: 0.88–0.96), was associated with a higher prevalence of TBI when pooling estimates across sites. Discussion Our analysis revealed that the prevalence of TBI in LMICs is similar to that of developed nations. Considering the growing impact of TBI on health resources in these countries, there is an urgent need for further research. PMID:26146992

  13. Constraints on hard spectator scattering and annihilation corrections in Bu,d → PV decays within QCD factorization

    NASA Astrophysics Data System (ADS)

    Sun, Junfeng; Chang, Qin; Hu, Xiaohui; Yang, Yueling

    2015-04-01

    In this paper, we investigate the contributions of hard spectator scattering and annihilation in B → PV decays within the QCD factorization framework. With available experimental data on B → πK* , ρK , πρ and Kϕ decays, comprehensive χ2 analyses of the parameters XA,Hi,f (ρA,Hi,f, ϕA,Hi,f) are performed, where XAf (XAi) and XH are used to parameterize the endpoint divergences of the (non)factorizable annihilation and hard spectator scattering amplitudes, respectively. Based on χ2 analyses, it is observed that (1) The topology-dependent parameterization scheme is feasible for B → PV decays; (2) At the current accuracy of experimental measurements and theoretical evaluations, XH = XAi is allowed by B → PV decays, but XH ≠ XAf at 68% C.L.; (3) With the simplification XH = XAi, parameters XAf and XAi should be treated individually. The above-described findings are very similar to those obtained from B → PP decays. Numerically, for B → PV decays, we obtain (ρA,Hi ,ϕA,Hi [ ° ]) = (2.87-1.95+0.66 , -145-21+14) and (ρAf, ϕAf [ ° ]) = (0.91-0.13+0.12 , -37-9+10) at 68% C.L. With the best-fit values, most of the theoretical results are in good agreement with the experimental data within errors. However, significant corrections to the color-suppressed tree amplitude α2 related to a large ρH result in the wrong sign for ACPdir (B- →π0K*-) compared with the most recent BABAR data, which presents a new obstacle in solving "ππ" and "πK" puzzles through α2. A crosscheck with measurements at Belle (or Belle II) and LHCb, which offer higher precision, is urgently expected to confirm or refute such possible mismatch.

  14. Five-Channel Polychromator Head

    NASA Technical Reports Server (NTRS)

    Eskridge, Richard; Dobson, Chris; Lee, Mike; Robertson, Tony

    1995-01-01

    Five-channel polychromator head samples Raman-scattering spectrum simultaneously at five wavelengths. Each channel consists of 1-mm fiber-optic cable that is individually translatable along dispersion axis of spectrometer to provide both flexibility and fine-tuning capability. Laser raman thermometer not thermometer in usual sense of word, but noncontact spectrometer that measures temperature indirectly in terms of relative intensities of selected Raman-scattering spectral lines.

  15. Critical assessment of enhancement factor measurements in surface-enhanced Raman scattering on different substrates.

    PubMed

    Rodrigues, Daniel C; de Souza, Michele L; Souza, Klester S; dos Santos, Diego P; Andrade, Gustavo F S; Temperini, Marcia L A

    2015-09-01

    The SERS enhancement factor (SERS-EF) is one of the most important parameters that characterizes the ability of a given substrate to enhance the Raman signal for SERS applications. The comparison of SERS intensities and SERS-EF values across different substrates is a common practice to unravel the performance of a given substrate. In this study, it is shown that such a comparison may lack significance if we compare substrates of very distinct nature and optical properties. It is specifically shown that the SERS-EF values for static substrates (e.g. immobilized metallic nanostructures) cannot be compared to those of dynamic ones (e.g. colloidal metal nanoparticle solutions), and that the optical properties for the latter show strong dependence on the metal-molecule interaction dynamics. The most representative experimental results concerning the dynamic substrates have been supported by generalized Mie theory simulations, which are tools used to describe the substrate complexity and the microscopic information not usually taken into account. PMID:25669424

  16. Head injury.

    PubMed

    Hureibi, K A; McLatchie, G R

    2010-05-01

    Head injury is one of the commonest injuries in sport. Most are mild but some can have serious outcomes. Sports medicine doctors should be able to recognise the clinical features and evaluate athletes with head injury. It is necessary during field assessment to recognise signs and symptoms that help in assessing the severity of injury and making a decision to return-to-play. Prevention of primary head injury should be the aim. This includes protective equipment like helmets and possible rule changes. PMID:20533694

  17. Head Injuries

    MedlinePlus

    ... before. Often, the injury is minor because your skull is hard and it protects your brain. But ... injuries can be more severe, such as a skull fracture, concussion, or traumatic brain injury. Head injuries ...

  18. Head Injuries

    MedlinePlus

    ... before. Usually, the injury is minor because your skull is hard and it protects your brain. But ... injuries can be more severe, such as a skull fracture, concussion, or traumatic brain injury. Head injuries ...

  19. Head Noises.

    ERIC Educational Resources Information Center

    Senior, Tom

    2000-01-01

    Explains how a toy called "Sound Bites" can be modified to demonstrate the transmission of sound waves. Students can hear music from the toy when they press it against any bone in their heads or shoulders. (WRM)

  20. Field calibration of multi-scattering correction factor for aethalometer aerosol absorption coefficient during CAPMEX Campaign, 2008

    NASA Astrophysics Data System (ADS)

    Kim, J. H.; Kim, S. W.; Yoon, S. C.; Park, R.; Ogren, J. A.

    2014-12-01

    Filter-based instrument, such as aethalometer, is being widely used to measure equivalent black carbon(EBC) mass concentration and aerosol absorption coefficient(AAC). However, many other previous studies have poited that AAC and its aerosol absorption angstrom exponent(AAE) are strongly affected by the multi-scattering correction factor(C) when we retrieve AAC from aethalometer EBC mass concentration measurement(Weingartner et al., 2003; Arnott et al., 2005; Schmid et al., 2006; Coen et al., 2010). We determined the C value using the method given in Weingartner et al. (2003) by comparing 7-wavelngth aethalometer (AE-31, Magee sci.) to 3-wavelength Photo-Acoustic Soot Spectrometer (PASS-3, DMT) at Gosan climate observatory, Korea(GCO) during Cheju ABC plume-asian monsoon experiment(CAPMEX) campaign(August and September, 2008). In this study, C was estimated to be 4.04 ± 1.68 at 532 nm and AAC retrieved with this value was decreased as approximately 100% as than that retrieved with soot case value from Weingartner et al (2003). We compared the AAC determined from aethalomter measurements to that from collocated Continuous Light Absorption Photometer (CLAP) measurements from January 2012 to December 2013 at GCO and found good agreement in both AAC and AAE. This result suggests the determination of site-specific C is crucially needed when we calculate AAC from aethalometer measurements.

  1. Model of beam head erosion

    SciTech Connect

    Lee, E.P.

    1980-08-08

    An analytical model of beam head dynamics is presented, leading to an estimate of the erosion rate due to the combined effects of Ohmic dissipation and scattering. Agreement with the results of a computer simulation and detailed one-dimensional computations is good in all respects except for the scaling of the erosion rate with net current.

  2. Weak charge form factor and radius of 208Pb through parity violation in electron scattering

    SciTech Connect

    Horowitz, C. J.; Ahmed, Z.; Jen, C. -M.; Rakhman, A.; Souder, P. A.; Dalton, M. M.; Liyanage, N.; Paschke, K. D.; Saenboonruang, K.; Silwal, R.; Franklin, G. B.; Friend, M.; Quinn, B.; Kumar, K. S.; McNulty, D.; Mercado, L.; Riordan, S.; Wexler, J.; Michaels, R. W.; Urciuoli, G. M.

    2012-03-26

    We use distorted wave electron scattering calculations to extract the weak charge form factor FW($\\bar{q}$), the weak charge radius RW, and the point neutron radius Rn, of 208Pb from the PREX parity violating asymmetry measurement. The form factor is the Fourier transform of the weak charge density at the average momentum transfer $\\bar{q}$ = 0.475 fm-1. We find FW($\\bar{q}$) = 0.204 ± 0.028(exp) ± 0.001(model). We use the Helm model to infer the weak radius from FW($\\bar{q}$). We find RW = 5.826 ± 0.181(exp) ± 0.027(model) fm. Here the exp error includes PREX statistical and systematic errors, while the model error describes the uncertainty in RW from uncertainties in the surface thickness σ of the weak charge density. The weak radius is larger than the charge radius, implying a 'weak charge skin' where the surface region is relatively enriched in weak charges compared to (electromagnetic) charges. We extract the point neutron radius Rn = 5.751 ± 0.175 (exp) ± 0.026(model) ± 0.005(strange) fm, from RW. Here there is only a very small error (strange) from possible strange quark contributions. We find Rn to be slightly smaller than RW because of the nucleon's size. As a result, we find a neutron skin thickness of Rn-Rp = 0.302 ± 0.175 (exp) ± 0.026 (model) ± 0.005 (strange) fm, where Rp is the point proton radius.

  3. Influence of inoculum and climatic factors on the severity of Fusarium head blight in German spring and winter barley.

    PubMed

    Linkmeyer, Andrea; Hofer, Katharina; Rychlik, Michael; Herz, Markus; Hausladen, Hans; Hückelhoven, Ralph; Hess, Michael

    2016-01-01

    Fusarium head blight (FHB) of small cereals is a disease of global importance with regard to economic losses and mycotoxin contamination harmful to human and animal health. In Germany, FHB is predominantly associated with wheat and F. graminearum is recognised as the major causal agent of the disease, but little is known about FHB of barley. Monitoring of the natural occurrence of FHB on Bavarian barley revealed differences for individual Fusarium spp. in incidence and severity of grain infection between years and between spring and winter barley. Parallel measurement of fungal DNA content in grain and mycotoxin content suggested the importance of F. graminearum in winter barley and of F. langsethiae in spring barley for FHB. The infection success of these two species was associated with certain weather conditions and barley flowering time. Inoculation experiments in the field revealed different effects of five Fusarium spp. on symptom formation, grain yield and mycotoxin production. A significant association between fungal infection of grain and mycotoxin content was observed following natural or artificial infection with the type B trichothecene producer F. culmorum, but not with the type A trichothecene-producing species F. langsethiae and F. sporotrichioides. Trichothecene type A toxin contamination also occurred in the absence of significant damage to grain and did not necessarily promote fungal colonisation. PMID:26679010

  4. Nephrotoxicity as a Dose-Limiting Factor in a High-Dose Cisplatin-Based Chemoradiotherapy Regimen for Head and Neck Carcinomas

    PubMed Central

    Hoek, Jantien; Bloemendal, Karen M.; van der Velden, Lilly-Ann A.; van Diessen, Judi N.A.; van Werkhoven, Erik; Klop, Willem M.C.; Tesselaar, Margot E.T.

    2016-01-01

    Purpose: Loco-regional control and organ preservation are significantly improved with concomitant cisplatin/radiotherapy and are compromised with less than 5% grade 3 nephrotoxicity (creatinine clearance 15–29 mL/min). However, although clinically important, in none of the randomized trials is grade 2 nephrotoxicity (defined as creatinine clearance 59–30 mL/min) mentioned. In this study, we assessed nephrotoxicity in daily practice among patients treated with high-dose cisplatin (100 mg/m2 on days 1, 22, and 43), concurrently with chemoradiotherapy (CCRT) and the impact on treatment modifications. Methods: 208 patients with advanced-stage malignancies of the head and neck region were evaluated. All patients were treated with high-dose cisplatin CCRT. The main outcome parameters were nephrotoxicity (defined as creatinine clearance grade 2 or more) and cumulative doses of cisplatin and radiation. Results: 133 patients (64%) completed all pre-planned courses of cisplatin. Nephrotoxicity was the main reason to discontinue the chemotherapy. Grade 3 nephrotoxicity was seen in 16 patients (8%) while grade 2 nephrotoxicity was seen in 53 patients (25%). Thirty six patients (17%) could not complete the pre-planned chemotherapy due to nephrotoxicity. Conclusions: In head and neck cancer patients, nephrotoxicity grade 2 is under-reported but is the major factor for discontinuing cisplatin during CCRT. PMID:26891330

  5. Use of Persistent Scatterer Interferometry to Assess Land Deformation in the Nile Delta and its Controlling Factors

    NASA Astrophysics Data System (ADS)

    Gebremichael, E.; Sultan, M.; Becker, R.; Emil, M.; Ahmed, M.; Chouinard, K.

    2015-12-01

    We applied Persistent scatterer interferometry (PSInSAR) to assess land deformation (subsidence and uplift) across the entire Nile delta and its surroundings and to identify possible causes of the observed deformation. For the purpose of the present study, 100 Envisat Advanced Synthetic Aperture Radar (ASAR; level 0) scenes that were acquired along four tracks and covering a time span of seven years (2004 to 2010) were used. The scenes extend from the Mediterranean coast in the north to Cairo city in the south. These scenes were focused using Repeat Orbit Interferometry PACkage (ROI_PAC) software and the subsequent PSI processing was done using the Stanford Method for Persistent Scatterers (StaMPS) method. A low coherence threshold (0.2) was used to decrease the impact of vegetation-related poor coherence and decorrelation of the scenes over the investigated time span. Subsidence was observed over: (1) the Demietta Nile River branch (3 to 14 mm/yr) where it intersects the Mediterranean coastline, (2) thick (~ 40 m) Holocene sediments in lake Manzala (up to 9 mm/yr), (3) reclaimed desert areas (west of Nile Delta; up to 12 mm/yr) of high groundwater extraction, (4) along parts of a previously proposed flexure line (up to 10 mm/yr), and (5) along the eastern sections of the Mediterranean coastline (up to 15.7 mm/yr). The city of Alexandria (underlain by carbonate platform) and the terminus of the Rosetta branch of the Nile River seem to experience almost no ground movement (mean subsidence of 0.28 mm/yr and 0.74 mm/yr respectively) while the cities of Ras Elbar and Port Said (underlain by thick Holocene sediment) exhibit the highest subsidence values (up to 14 mm/yr and 8.5 mm/yr respectively). The city of Cairo has also experienced subsidence in limited areas of up to 7.8 mm/yr. High spatial correlation was also observed between the subsiding areas and the Abu Madi incised valley; the largest gas field in the Nile Delta. Most of the area undergoing subsidence in the

  6. Risk Factors for Hearing Loss in Patients Treated With Intensity-Modulated Radiotherapy for Head-and-Neck Tumors

    SciTech Connect

    Zuur, Charlotte L.; Dreschler, Wouter A.; Balm, Alfons J.; Rasch, Coen R.

    2009-06-01

    Purpose: Radiotherapy (RT) is a common treatment of head-and-neck carcinoma. The objective of this study was to perform a prospective multivariate assessment of the dose-effect relationship between intensity-modulated RT and hearing loss. Methods and Materials: Pure tone audiometry at 0.250-16 kHz was obtained before and after treatment in 101 patients (202 ears). All patients received full-course intensity-modulated RT (range, 56-70 Gy), with a median cochlear dose of 11.4 Gy (range, 0.2-69.7). Results: Audiometry was performed 1 week before and a median of 9 weeks (range, 1-112) after treatment. The mean hearing deterioration at pure tone average air-conduction 1-2-4 kHz was small (from 28.6 dB HL to 30.1 dB HL). However, individual patients showed clinically significant hearing loss, with 10-dB threshold shift incidences of 13% and 18% at pure tone averages air-conduction 1-2-4 kHz and 8-10-12.5 kHz, respectively. Post-treatment hearing capability was unfavorable in the case of greater inner ear radiation doses (p <0.0001), unfavorable baseline hearing capability (p <0.0001), green-eyed patients (p <0.0001), and older age (p <0.0001). Using multivariate analysis, a prediction of individual hearing capabiltity after treatment was made. Conclusion: RT-induced hearing loss in the mean population is modest. However, clinically significant hearing loss was observed in older patients with green eyes and unfavorable pretreatment hearing. In these patients, the intended radiation dose may be adjusted according to the proposed predictive model, aiming to decrease the risk of ototoxicity.

  7. Prevalence of Nontraumatic Osteonecrosis of the Femoral Head and its Associated Risk Factors in the Chinese Population: Results from a Nationally Representative Survey

    PubMed Central

    Zhao, De-Wei; Yu, Mang; Hu, Kai; Wang, Wei; Yang, Lei; Wang, Ben-Jie; Gao, Xiao-Hong; Guo, Yong-Ming; Xu, Yong-Qing; Wei, Yu-Shan; Tian, Si-Miao; Yang, Fan; Wang, Nan; Huang, Shi-Bo; Xie, Hui; Wei, Xiao-Wei; Jiang, Hai-Shen; Zang, Yu-Qiang; Ai, Jun; Chen, Yuan-Liang; Lei, Guang-Hua; Li, Yu-Jin; Tian, Geng; Li, Zong-Sheng; Cao, Yong; Ma, Li

    2015-01-01

    Background: Nontraumatic osteonecrosis of the femoral head (NONFH) is a debilitating disease that represents a significant financial burden for both individuals and healthcare systems. Despite its significance, however, its prevalence in the Chinese general population remains unknown. This study aimed to investigate the prevalence of NONFH and its associated risk factors in the Chinese population. Methods: A nationally representative survey of 30,030 respondents was undertaken from June 2012 to August 2013. All participants underwent a questionnaire investigation, physical examination of hip, and bilateral hip joint X-ray and/or magnetic resonance imaging examination. Blood samples were taken after overnight fasting to test serum total cholesterol, triglyceride, and high-density lipoprotein (HDL) and low-density lipoprotein (LDL) levels. We then used multivariate logistic regression analysis to investigate the associations between various metabolic, demographic, and lifestyle-related variables and NONFH. Results: NONFH was diagnosed in 218 subjects (0.725%) and the estimated NONFH cases were 8.12 million among Chinese people aged 15 years and over. The prevalence of NONFH was significantly higher in males than in females (1.02% vs. 0.51%, χ2 = 24.997, P < 0.001). Among NONFH patients, North residents were subjected to higher prevalence of NONFH than that of South residents (0.85% vs. 0.61%, χ2 = 5.847, P = 0.016). Our multivariate regression analysis showed that high blood levels of triglycerides, total cholesterol, LDL-cholesterol, and non-HDL-cholesterol, male, urban residence, family history of osteonecrosis of the femoral head, heavy smoking, alcohol abuse and glucocorticoid intake, overweight, and obesity were all significantly associated with an increased risk of NONFH. Conclusions: Our findings highlight that NONFH is a significant public health challenge in China and underscore the need for policy measures on the national level. Furthermore, NONFH shares

  8. Structural and functional characterisation of the fork head transcription factor-encoding gene, Hc-daf-16, from the parasitic nematode Haemonchus contortus (Strongylida)

    PubMed Central

    Hu, Min; Lok, James B.; Ranjit, Najju; Massey, Holman C.; Sternberg, Paul W.; Gasser, Robin B.

    2010-01-01

    Despite their phylogenetic diversity, parasitic nematodes share attributes of longevity and developmental arrest (=hypobiosis) with free-living nematodes at key points in their life cycles, particularly in larval stages responsible for establishing infection in the host. Insulin-like signalling plays crucial roles in the regulation of life span and arrest (=dauer formation) in the free-living nematode, Caenorhabditis elegans. Insulin-like signalling in C. elegans negatively regulates the fork head boxO (FoxO) transcription factor encoded by daf-16, which is linked to initiating a dauer-specific pattern of gene expression. Orthologues of daf-16 have been identified in several species of parasitic nematode. Although function has been demonstrated for an orthologue from the parasitic nematode Strongyloides stercoralis (Rhabditida), the functional capabilities of homologues/orthologues in bursate nematodes (Strongylida) are unknown. In the present study, we used a genomic approach to determine the structures of two complete daf-16 orthologues (designated Hc-daf-16.1 and Hc-daf-16.2) and their transcripts in the parasitic nematode Haemonchus contortus, and assessed their function(s) using C. elegans as a genetic surrogate. Unlike the multiple isoforms of Ce-DAF-16 and Ss-DAF-16, which are encoded by a single gene and produced by alternative splicing, mRNAs encoding the proteins Hc-DAF-16.1 and Hc-DAF-16.2 are transcribed from separate and distinct loci. Both orthologues are transcribed in all developmental stages and both sexes of H. contortus, and the inferred proteins (603 and 556 amino acids) each contain a characteristic, highly conserved fork head domain. In spite of distinct differences in genomic organisation compared with orthologues in C. elegans and S. stercoralis, genetic complementation studies demonstrated here that Hc-daf-16.2, but not Hc-daf-16.1, could restore daf-16 function to a C. elegans strain carrying a null mutation at this locus. These findings

  9. Active head rotations and eye-head coordination

    NASA Technical Reports Server (NTRS)

    Zangemeister, W. H.; Stark, L.

    1981-01-01

    It is pointed out that head movements play an important role in gaze. The interaction between eye and head movements involves both their shared role in directing gaze and the compensatory vestibular ocular reflex. The dynamics of head trajectories are discussed, taking into account the use of parameterization to obtain the peak velocity, peak accelerations, the times of these extrema, and the duration of the movement. Attention is given to the main sequence, neck muscle EMG and details of the head-movement trajectory, types of head model accelerations, the latency of eye and head movement in coordinated gaze, gaze latency as a function of various factors, and coordinated gaze types. Clinical examples of gaze-plane analysis are considered along with the instantaneous change of compensatory eye movement (CEM) gain, and aspects of variability.

  10. Adolescent motherhood and developmental outcomes of children in early head start: the influence of maternal parenting behaviors, well-being, and risk factors within the family setting.

    PubMed

    Rafferty, Yvonne; Griffin, Kenneth W; Lodise, Michelle

    2011-04-01

    This longitudinal study examined the influence of parenting behaviors, well-being, and risk factors of low-income adolescent mothers on the cognitive and language abilities of children from infancy to age 3. Participants consisted of 1,240 mother-child dyads enrolled in the Early Head Start Research and Evaluation Project. Data were collected using structured interviews with the mothers and from videotaped mother-child interactions during play activities when children were approximately 14 months old and again at 36 months of age. Positive parenting behaviors exhibited toward the 14-month-old children predicted gains in both cognitive and language abilities more so than did maternal well-being, risk factors within the family setting, and demographic risk factors. Gains in cognitive abilities from infancy to age 3 were predicted by supportive parenting, higher family resources, and lower family conflict when children were infants. Gains in language abilities were predicted by supportive parenting, support for language and learning in the home environment, and higher family resources when children were infants. Finally, path analyses showed that maternal age had an indirect effect on child cognitive and language abilities at age 3 through effects on parenting behaviors. Older mothers were more likely to be supportive during play at age 14 months, which in turn promoted enhanced developmental outcomes at age 3. Implications for intervention and future research are discussed. PMID:21486265

  11. Small angle X-ray scattering data and structure factor fitting for the study of the quaternary structure of the spermidine N-acetyltransferase SpeG

    PubMed Central

    Weigand, Steven; Filippova, Ekaterina V.; Kiryukhina, Olga; Anderson, Wayne F.

    2015-01-01

    Here we describe the treatment of the small-angle X-ray Scattering (SAXS) data used during SpeG quaternary structure study as part of the research article “Substrate induced allosteric change in the quaternary structure of the spermidine N-acetyltransferase SpeG” published in Journal of Molecular Biology [1]. These data were collected on two separate area detectors as separate dilution series of the SpeG and the SpeG with spermine samples along with data from their companion buffers. The data were radially integrated, corrected for incident beam variation, and scaled to absolute units. After subtraction of volume-fraction scaled buffer scattering and division by the SpeG concentration, multiple scattering curves free of an inter-molecular structure factor were derived from the dilution series. Rather than extrapolating to infinite dilution, the structure factor contribution was estimated by fitting to the full set of data provided by dividing the scattering curves of a dilution series by the curve from the most dilute sample in that series. PMID:26793756

  12. Small angle X-ray scattering data and structure factor fitting for the study of the quaternary structure of the spermidine N-acetyltransferase SpeG.

    PubMed

    Weigand, Steven; Filippova, Ekaterina V; Kiryukhina, Olga; Anderson, Wayne F

    2016-03-01

    Here we describe the treatment of the small-angle X-ray Scattering (SAXS) data used during SpeG quaternary structure study as part of the research article "Substrate induced allosteric change in the quaternary structure of the spermidine N-acetyltransferase SpeG" published in Journal of Molecular Biology [1]. These data were collected on two separate area detectors as separate dilution series of the SpeG and the SpeG with spermine samples along with data from their companion buffers. The data were radially integrated, corrected for incident beam variation, and scaled to absolute units. After subtraction of volume-fraction scaled buffer scattering and division by the SpeG concentration, multiple scattering curves free of an inter-molecular structure factor were derived from the dilution series. Rather than extrapolating to infinite dilution, the structure factor contribution was estimated by fitting to the full set of data provided by dividing the scattering curves of a dilution series by the curve from the most dilute sample in that series. PMID:26793756

  13. Risk factors for developing a second upper aerodigestive cancer after radiotherapy with or without chemotherapy in patients with head-and-neck cancers: An exploratory outcomes analysis

    SciTech Connect

    Taussky, Daniel . E-mail: daniel.taussky.chum@ssss.gouv.qc.ca; Rufibach, Kaspar M.Sc.; Huguenin, Pia; Allal, Abdelkarim S.

    2005-07-01

    Purpose: The objective was to assess the influence of treatment-related and patient-related factors on the risk of developing a second primary tumor (SPT) of the upper aerodigestive tract (UADT) in patients with locoregionally advanced nonmetastatic carcinomas of the head-and-neck region. Methods and Materials: The data of 521 patients with a minimum follow-up of 1 year were pooled: 224 patients from the Swiss Group for Clinical Cancer Research (SAKK) 10/94 trial, treated with 1.2 Gy b.i.d. to 74.4 Gy, and randomized to receive or not to receive simultaneous chemotherapy with cisplatin (excluding nasopharyngeal and maxillary sinus carcinomas); and 297 patients from Geneva, all treated with accelerated radiotherapy with concomitant boost to 69.9 Gy and predominantly cisplatin-based concomitant chemotherapy in 33% of patients (including 21 patients with nasopharyngeal carcinomas). An exploratory analysis using competing risk methodology was performed. Results: A total of 65 SPT of the UADT were observed after a median observation time of 4.7 years. The overall risk of experiencing an SPT of the UADT at 10 years in the presence of all other possible events was estimated to be 33%. There were no SPTs after treatment for nasopharyngeal carcinoma. In a multivariate logistic regression analysis, there was no difference in occurrence of SPT at 3 years with respect to the administration of chemotherapy (p = 0.31), age (p 0.62), performance status (p = 0.61), gender (p = 0.27), presence of nodal disease (p = 0.51), or T stage (p = 0.72). However, patients treated with concomitant boost had fewer SPTs (p = 0.0093). Conclusions: Our data do not suggest that addition of chemotherapy to radiotherapy influences the incidence of second cancers in patients with head-and-neck cancer. The difference in the incidence of SPT between the two radiotherapy schedule groups merits further exploration.

  14. Cone Heads

    ERIC Educational Resources Information Center

    Coy, Mary

    2005-01-01

    The author, a middle school art teacher, describes a sculpture project lesson involving Cone Heads (sculptures made from cardboard cones). Discussion of caricatures with exaggerated facial features and interesting profiles helped students understand that the more expressive the face, the better. This project took approximately four to five…

  15. Irradiation-Induced Regulation of Plasminogen Activator Inhibitor Type-1 and Vascular Endothelial Growth Factor in Six Human Squamous Cell Carcinoma Lines of the Head and Neck

    SciTech Connect

    Artman, Tuuli; Schilling, Daniela; Multhoff, Gabriele

    2010-02-01

    Purpose: It has been shown that plasminogen activator inhibitor type-1 (PAI-1) and vascular endothelial growth factor (VEGF) are involved in neo-angiogenesis. The aim of this study was to investigate the irradiation-induced regulation of PAI-1 and VEGF in squamous cell carcinomas of the head and neck (SCCHN) cell lines of varying radiation sensitivity. Methods and Materials: Six cell lines derived from SCCHN were investigated in vitro. The colorimetric AlamarBlue assay was used to detect metabolic activity of cell lines during irradiation as a surrogate marker for radiation sensitivity. PAI-1 and VEGF secretion levels were measured by enzyme-linked immunosorbent assay 24, 48, and 72 h after irradiation with 0, 2, 6, and 10 Gy. The direct radioprotective effect of exogenous PAI-1 was measured using the clonogenic assay. For regulation studies, transforming growth factor-beta1 (TGF-beta1), hypoxia-inducible factor-1alpha (HIF-1alpha), hypoxia-inducible factor-2alpha (HIF-2alpha), or both HIF-1alpha and HIF-2alpha were downregulated using siRNA. Results: Although baseline levels varied greatly, irradiation led to a comparable dose-dependent increase in PAI-1 and VEGF secretion in all six cell lines. Addition of exogenous stable PAI-1 to the low PAI-1-expressing cell lines, XF354 and FaDu, did not lead to a radioprotective effect. Downregulation of TGF-beta1 significantly decreased VEGF secretion in radiation-sensitive XF354 cells, and downregulation of HIF-1alpha and HIF-2alpha reduced PAI-1 and VEGF secretion in radiation-resistant SAS cells. Conclusions: Irradiation dose-dependently increased PAI-1 and VEGF secretion in all SCCHN cell lines tested regardless of their basal levels and radiation sensitivity. In addition, TGF-beta1 and HIF-1alpha could be partly responsible for VEGF and PAI-1 upregulation after irradiation.

  16. Contribution of Coulomb explosion to form factors and mosaicity spread in single particle X-ray scattering.

    PubMed

    Debnarova, Andrea; Techert, Simone; Schmatz, Stefan

    2014-01-14

    The Coulomb explosion of the octamer water cluster has been studied employing time-dependent density functional theory explicitly accounting for the laser field and thus not imposing any constraint on the interaction between the laser pulse and the cluster. We focus on the effects of electron density changes in the system under high-intensity (10(16) and 10(15) W cm(-2)) soft X-ray laser pulses and their fingerprint in the reciprocal space, namely the ultrafast changes in X-ray diffuse scattering signals in k-space (in the investigated k-space range from 10(-3) up to 10 Å(-1)). The present simulations indicate that diffusional components in X-ray intensity changes propagate from low reciprocal resolution (resembling the small-angle X-ray scattering regime) to very high resolution (the wide-angle X-ray scattering regime) during the Coulomb explosion process. PMID:24276436

  17. Comparison of techniques that use the single scattering model to compute the quality factor Q from coda waves

    USGS Publications Warehouse

    Novelo-Casanova, D. A.; Lee, W.H.K.

    1991-01-01

    Using simulated coda waves, the resolution of the single-scattering model to extract coda Q (Qc) and its power law frequency dependence was tested. The back-scattering model of Aki and Chouet (1975) and the single isotropic-scattering model of Sato (1977) were examined. The results indicate that: (1) The input Qc models are reasonably well approximated by the two methods; (2) almost equal Qc values are recovered when the techniques sample the same coda windows; (3) low Qc models are well estimated in the frequency domain from the early and late part of the coda; and (4) models with high Qc values are more accurately extracted from late code measurements. ?? 1991 Birkha??user Verlag.

  18. An Analysis of Heavy-Ion Elastic Scattering Processes Using Numerical Model Based on the Partial Wave Parameterised S-Matrix with Regge Pole Factor

    NASA Astrophysics Data System (ADS)

    Badran, R. I.; Al-Lehyani, I. H.

    2016-04-01

    Analyses of the angular distributions in the elastic scattering processes of 9, 10, 11Be by the target nucleus 64Zn at the laboratory energies of 27.95 MeV, and 4, 6, 8He by the target nucleus 208Pb at the laboratory energy of 22 MeV are performed. These analyses rely on a numerical model based on a parameterised scattering matrix (S-matrix) derived from Frahn and Venter. They confirm the absence of the Coulomb rainbow peak in angular distributions of elastic scattering in collisions of halo nuclei at energies around the Coulomb barrier. The correlation between the total reaction cross section and the halo structure for each scattering that involves a halo nucleus is discussed, and values of the total reaction cross section are found comparable with those of others. The diffractive features of the systems 16, 18O + 19F at specific laboratory energies are examined, and the effect of exchanging the projectile and target nuclei at such energies on these features are inspected. The incorporation of the Regge pole factor into the parameterised S-matrix calculations, which is found important in some cases, is employed in order to account for the oscillatory structure (if available) at backward angles. The theoretical results are found reasonable, reproducing the general pattern of the data. The trend of the extracted parameters meets the requirements proposed by the adopted models.

  19. An Analysis of Heavy-Ion Elastic Scattering Processes Using Numerical Model Based on the Partial Wave Parameterised S-Matrix with Regge Pole Factor

    NASA Astrophysics Data System (ADS)

    Badran, R. I.; Al-Lehyani, I. H.

    2016-06-01

    Analyses of the angular distributions in the elastic scattering processes of 9, 10, 11Be by the target nucleus 64Zn at the laboratory energies of 27.95 MeV, and 4, 6, 8He by the target nucleus 208Pb at the laboratory energy of 22 MeV are performed. These analyses rely on a numerical model based on a parameterised scattering matrix (S-matrix) derived from Frahn and Venter. They confirm the absence of the Coulomb rainbow peak in angular distributions of elastic scattering in collisions of halo nuclei at energies around the Coulomb barrier. The correlation between the total reaction cross section and the halo structure for each scattering that involves a halo nucleus is discussed, and values of the total reaction cross section are found comparable with those of others. The diffractive features of the systems 16, 18O + 19F at specific laboratory energies are examined, and the effect of exchanging the projectile and target nuclei at such energies on these features are inspected. The incorporation of the Regge pole factor into the parameterised S-matrix calculations, which is found important in some cases, is employed in order to account for the oscillatory structure (if available) at backward angles. The theoretical results are found reasonable, reproducing the general pattern of the data. The trend of the extracted parameters meets the requirements proposed by the adopted models.

  20. Working memory units are all in your head: Factors that influence whether features or objects are the favored units.

    PubMed

    Vergauwe, Evie; Cowan, Nelson

    2015-09-01

    We compared two contrasting hypotheses of how multifeatured objects are stored in visual working memory (vWM); as integrated objects or as independent features. A new procedure was devised to examine vWM representations of several concurrently held objects and their features and our main measure was reaction time (RT), allowing an examination of the real-time search through features and/or objects in an array in vWM. Response speeds to probes with color, shape, or both were studied as a function of the number of memorized colored shapes. Four testing groups were created by varying the instructions and the way in which probes with both color and shape were presented. The instructions explicitly either encouraged or discouraged the use of binding information and the task-relevance of binding information was further suggested by presenting probes with both color and shapes as either integrated objects or independent features. Our results show that the unit used for retrieval from vWM depends on the testing situation. Search was fully object-based only when all factors support that basis of search, in which case retrieving 2 features took no longer than retrieving a single feature. Otherwise, retrieving 2 features took longer than retrieving a single feature. Additional analyses of change detection latency suggested that, even though different testing situations can result in a stronger emphasis on either the feature dimension or the object dimension, neither one disappears from the representation and both concurrently affect change detection performance. PMID:25705873

  1. Risk Factors of Ototoxicity After Cisplatin-Based Chemo-Irradiation in Patients With Locally Advanced Head-and-Neck Cancer: A Multivariate Analysis

    SciTech Connect

    Zuur, Charlotte L. . E-mail: cl.zuur@vumc.nl; Simis, Yvonne J.; Lansdaal, Pauline E.; Hart, Augustinus A.; Rasch, Coen R.; Schornagel, Jan H.; Dreschler, Wouter A.; Balm, Alfons J.

    2007-08-01

    Purpose: Cisplatin chemo-irradiation is increasingly used in locally advanced squamous cell carcinoma of the head and neck. The objective of this study is to determine risk factors of ototoxicity due to intra-arterial high-dose cisplatin chemoradiation. Methods and Materials: A prospective analysis of hearing thresholds at low and (ultra) high frequencies obtained before, during, and after treatment in 146 patients. Treatment consisted of intra-arterial infusion of high-dose cisplatin (150 mg/m{sup 2}, four courses) with sodium thiosulfate rescue and concurrent radiation therapy (70 Gy). Patient and chemoradiation variables were studied in a multivariate analysis. Results: After treatment, 23% of the ears were under consideration for hearing aids because of therapy. Twenty-two percent of the patients developed an increase in air-bone gap >10 dB during or after therapy. In the multivariate explanatory analysis, cumulative dose of cisplatin and radiation therapy, and young age displayed a causal relationship with increased sensorineural hearing loss during and after therapy (p < 0.001). In the multivariate prediction analysis, pretreatment hearing level of the concerning ear was identified as an independent predictive factor for hearing capability after therapy (p < 0.0001). Conclusions: Both cisplatin and radiation therapy were proven to induce sensorineural hearing loss, in this study with short-term follow-up. Of all patient and treatment variables studied, the patients pretreatment hearing level appeared to be the main predictive factor for hearing capability after high-dose intra-arterial cisplatin chemoradiation.

  2. A Measurement of the Neutron Electric Form Factor in Dvec (evec,e'n)p Quasielastic Scattering at Q2=0.5(GeV/c)2

    SciTech Connect

    Hongguo Zhu

    2000-08-01

    The form factors of the neutron give information on fundamental properties of the nucleons and provide a critical testing ground for models based on QCD. In late 1998, Jefferson Lab (JLAB) experiment E93-026 measured the spin-dependent part of the exclusive (e, e'n) scattering cross section from a polarized deuterated ammonia ({sup 15}ND{sub 3}) target at a four momentum transfer squared of Q{sup 2} = 0.5 (GeV/c){sub 2}. A longitudinally polarized electron beam was scattered from the polarized target and the quasi-elastically scattered electron was detected in coincidence with the knocked-out neutron. The data have been analyzed in terms of the spin-correlation parameter, or the electron-deuteron vector asymmetry (A{sub ed}{sup V}), of (e, e'n) to determine the neutron electric form factor G{sub E}{sup n}. The result is consistent with data from existing experiments and shows a good agreement with the Galster parameterization of G{sub E}{sup n} within experimental uncertainty.

  3. Rayleigh Scattering.

    ERIC Educational Resources Information Center

    Young, Andrew T.

    1982-01-01

    The correct usage of such terminology as "Rayleigh scattering,""Rayleigh lines,""Raman lines," and "Tyndall scattering" is resolved during an historical excursion through the physics of light-scattering by gas molecules. (Author/JN)

  4. Near-field-assisted localization: effect of size and filling factor of randomly distributed zinc oxide nanoneedles on multiple scattering and localization of light

    NASA Astrophysics Data System (ADS)

    Silies, Martin; Mascheck, Manfred; Leipold, David; Kollmann, Heiko; Schmidt, Slawa; Sartor, Janos; Yatsui, Takashi; Kitamura, Kokoro; Ohtsu, Motoicho; Kalt, Heinz; Runge, Erich; Lienau, Christoph

    2016-07-01

    We investigate the influence of the diameter and the filling factor of randomly arranged ZnO nanoneedles on the multiple scattering and localization of light in disordered dielectrics. Coherent, ultra-broadband second-harmonic (SH) microscopy is used to probe the spatial localization of light in representative nm-sized ZnO arrays of needles. We observe strong fluctuations of the SH intensity inside different ZnO needle geometries. Comparison of the SH intensity distributions with predictions based on a one-parameter scaling model indicate that SH fluctuations can be taken as a quantitative measure for the degree of localization. Interestingly, the strongest localization signatures are found for densely packed arrays of thin needles with diameters in the range of only 30 nm range, despite the small scattering cross section of these needles. FDTD simulations indicate that in this case coupling of electric near-fields between neighbouring needles governs the localization.

  5. Inclusive scattering of polarized electrons on polarized {sup 3}He: Effects of final state interaction and the magnetic form factor of the neutron

    SciTech Connect

    Ishikawa, S.; Golak, J.; Witala, H.; Kamada, H.; Gloeckle, W.; Hueber, D.

    1998-01-01

    Effects of final state interaction on asymmetries in inclusive scattering of polarized electrons on polarized {sup 3}He are investigated using a consistent {sup 3}He bound state wave function and 3N continuum scattering states. Significant effects are found, which influence the extraction of the magnetic neutron form factor from A{sub T{sup {prime}}}. The enhancement found experimentally for A{sub TL{sup {prime}}} near the 3N breakup threshold, which could not be explained in calculations carried through in plane wave impulse approximation up to now, occurs now also in theory if the full final state interaction is included. {copyright} {ital 1998} {ital The American Physical Society}

  6. Determination of {sup 16}O and {sup 18}O sensitivity factors and charge-exchange processes in low-energy ion scattering

    SciTech Connect

    Tellez, H.; Chater, R. J.; Fearn, S.; Symianakis, E.; Kilner, J. A.; Brongersma, H. H.

    2012-10-08

    Quantitative analysis in low-energy ion scattering (LEIS) requires an understanding of the charge-exchange processes to estimate the elemental sensitivity factors. In this work, the neutralization of He{sup +} scattered by {sup 18}O-exchanged silica at energies between 0.6 and 7 keV was studied. The process is dominated by Auger neutralization for E{sub i} < 0.8 keV. An additional mechanism starts above the reionization threshold. This collision-induced neutralization becomes the dominant mechanism for E{sub i} > 2 keV. The ion fractions P{sup +} were determined for Si and O using the characteristic velocity method to quantify the surface density. The {sup 18}O/{sup 16}O sensitivity ratio indicates an 18% higher sensitivity for the heavier O isotope.

  7. Combined Inhibition of c-Src and Epidermal Growth Factor Receptor Abrogates Growth and Invasion of Head and Neck Squamous Cell Carcinoma

    PubMed Central

    Koppikar, Priya; Choi, Seung-Ho; Egloff, Ann Marie; Cai, Quan; Suzuki, Shinsuke; Freilino, Maria; Nozawa, Hiroshi; Thomas, Sufi M.; Gooding, William E.; Siegfried, Jill M.; Grandis, Jennifer R.

    2012-01-01

    Purpose Increased expression and/or activation of epidermal growth factor receptor (EGFR) is associated with tumor progression and poor prognosis in many cancers including head and neck squamous cell carcinoma (HNSCC). Src family kinases, including c-Src, mediate a variety of intra- or extracellular signals that contribute to tumor formation and progression. This study was undertaken to elucidate the role of c-Src in the growth and invasion of HNSCC and to determine the effects of combined targeting of EGFR and Src kinases in HNSCC cell lines. Experimental design HNSCC cells were engineered to stably express a dominant-active (DA) form of c-Src and investigated in cell growth and invasion assays. The biochemical effects of combined treatment with the Src inhibitor, AZD0530, a potent, orally active Src inhibitor with Bcr/Abl activity and the EGFR kinase inhibitor, gefitinib, were examined as well as the consequences of dual Src/EGFR targeting on the growth and invasion of a panel of HNSCC cell lines. Results HNSCC cells expressing DA c-Src demonstrated increased growth and invasion compared with vector-transfected controls. Combined treatment with AZD0530 and gefitinib resulted in greater inhibition of HNSCC cell growth and invasion compared with either agent alone. Conclusions These results suggest that increased expression and activation of c-Src promotes HNSCC progression where combined targeting of EGFR and c-Src may be an efficacious treatment approach. PMID:18594011

  8. Spectator scattering and annihilation contributions as a solution to the πK and ππ puzzles within QCD factorization approach

    NASA Astrophysics Data System (ADS)

    Chang, Qin; Sun, Junfeng; Yang, Yueling; Li, Xiaonan

    2014-09-01

    The large branching ratios for pure annihilation B ¯s0→π+π- and B ¯d0→K+K- decays reported by CDF and LHCb collaborations recently and the so-called πK and ππ puzzles indicate that spectator scattering and annihilation contributions are important to the penguin-dominated, color-suppressed tree dominated, and pure annihilation nonleptonic B decays. Combining the available experimental data for Bu ,d→ππ, πK and KK ¯ decays, we do a global fit on the spectator scattering and annihilation parameters XH(ρH,ϕH), XAi(ρAi,ϕAi) and XAf(ρAf,ϕAf), which are used to parametrize the end point singularity in amplitudes of spectator scattering, nonfactorizable and factorizable annihilation topologies within the QCD factorization framework, in three scenarios for different purpose. Numerically, in Scenario II, we get (ρAi,ϕAi[∘])=(2.88-1.30+1.52,-103-40+33) and (ρAf,ϕAf[∘])=(1.21-0.25+0.22,-40-8+12) at the 68% confidence level, which are mainly demanded by resolving the πK puzzle and confirm the presupposition that XAi≠XAf. In addition, correspondingly, the B-meson wave function parameter λB is also fitted to be 0.18-0.08+0.11 MeV, which plays an important role for resolving both πK and ππ puzzles. With the fitted parameters, the QCD factorization results for observables of Bu ,d→ππ, πK and KK ¯ decays are in good agreement with experimental measurements. Many more experimental and theoretical efforts are expected to understand the underlying QCD dynamics of spectator scattering and annihilation contributions.

  9. SU-E-T-59: Calculations of Collimator Scatter Factors (Sc) with and Without Custom-Made Build-Up Caps for CyberKnife

    SciTech Connect

    Wokoma, S; Yoon, J; Jung, J; Lee, S

    2014-06-01

    Purpose: To investigate the impact of custom-made build-up caps for a diode detector in robotic radiosurgery radiation fields with variable collimator (IRIS) for collimator scatter factor (Sc) calculation. Methods: An acrylic cap was custom-made to fit our SFD (IBA Dosimetry, Germany) diode detector. The cap has thickness of 5 cm, corresponding to a depth beyond electron contamination. IAEA phase space data was used for beam modeling and DOSRZnrc code was used to model the detector. The detector was positioned at 80 cm source-to-detector distance. Calculations were performed with the SFD, with and without the build-up cap, for clinical IRIS settings ranging from 7.5 to 60 mm. Results: The collimator scatter factors were calculated with and without 5 cm build-up cap. They were agreed within 3% difference except 15 mm cone. The Sc factor for 15 mm cone without buildup was 13.2% lower than that with buildup. Conclusion: Sc data is a critical component in advanced algorithms for treatment planning in order to calculate the dose accurately. After incorporating build-up cap, we discovered differences of up to 13.2 % in Sc factors in the SFD detector, when compared against in-air measurements without build-up caps.

  10. A Measurement of the neutron electric form factor at very large momentum transfer using polaried electrions scattering from a polarized helium-3 target

    SciTech Connect

    Kelleher, Aidan

    2010-02-01

    Knowledge of the electric and magnetic elastic form factors of the nucleon is essential for an understanding of nucleon structure. Of the form factors, the electric form factor of the neutron has been measured over the smallest range in Q2 and with the lowest precision. Jefferson Lab experiment 02-013 used a novel new polarized 3 He target to nearly double the range of momentum transfer in which the neutron form factor has been studied and to measure it with much higher precision. Polarized electrons were scattered off this target, and both the scattered electron and neutron were detected. Gn E was measured to be 0.0242 ± 0.0020(stat) ± 0.0061(sys) and 0.0247 ± 0.0029(stat) ± 0.0031(sys) at Q2 = 1.7 and 2.5 GeV2 , respectively.

  11. Analysis of Scattered Radiation in an Irradiated Body by Means of the Monte Carlo Simulation: Back-scatter Factors of Diagnostic X-rays in the Incident Surface Which is Not Flat.

    PubMed

    Kato, Hideki; Minami, Kazuyuki; Asada, Yasuki; Suzuki, Shoichi

    2016-05-01

    To obtain patient entrance surface dose in X-ray photography, a calculation method based on measured exposure or air kerma radiated from X-ray tube is generally used. Two factors are necessary for this calculation: (1) exposure/air kerma to absorb dose conversion factor and (2) back-scatter factor (BSF) based on X-ray quality and on field size. These BSFs are commonly obtained by interpolation from existent data which were given for a water phantom whose entrance surface is flat. Since patient's surface in X-ray photograph is not flat, some error may occur when existent BSF is used in this calculation. In this article, BSF for water phantom with cylindrical surface and elliptic cylinder surface were calculated by means of the Monte Carlo simulation. And these BSFs were compared with BSF for flat surface phantom. As a result (1) radius of curvature of cylindrical phantom or horizontal axis of elliptic cylinder phantom is smaller, (2) half value layer of X-ray is larger, (3) field size is larger, difference of these BSF with that for flat surface phantom tends to be larger. Maximum difference by calculation condition assumed in this article was more than 10%. The cause of this difference is because scattering volume in irradiated body of cylindrical or elliptic cylinder phantom is smaller than flat surface phantom. To obtain patient entrance surface dose more precisely, it is necessary to use BSF respectively calculated for phantom resembling patient's body such as cylindrical or elliptic cylinder phantom by means of the Monte Carlo simulation. PMID:27211084

  12. Basic helix-loop-helix transcription factor BcbHLHpol functions as a positive regulator of pollen development in non-heading Chinese cabbage.

    PubMed

    Liu, Tongkun; Li, Ying; Zhang, Changwei; Duan, Weike; Huang, Feiyi; Hou, Xilin

    2014-12-01

    Cytoplasmic male sterility (CMS) is a common trait in higher plants, and several transcription factors regulate pollen development. Previously, we obtained a basic helix-loop-helix transcription factor, BcbHLHpol, via suppression subtractive hybridization in non-heading Chinese cabbage. However, the regulatory function of BcbHLHpol during anther and pollen development remains unclear. In this study, BcbHLHpol was cloned, and its tissue-specific expression profile was analyzed. The results of real-time polymerase chain reaction showed that BcbHLHpol was highly expressed in maintainer buds and that the transcripts of BcbHLHpol significantly decreased in the buds of pol CMS. A virus-induced gene silencing vector that targets BcbHLHpol was constructed and transformed into Brassica campestris plants to further explore the function of BcbHLHpol. Male sterility and short stature were observed in BcbHLHpol-silenced plants. The degradation of tapetal cells was inhibited in BcbHLHpol-silenced plants, and nutrients were insufficiently supplied to the microspore. These phenomena resulted in pollen abortion. This result indicates that BcbHLHpol functions as a positive regulator in pollen development. Yeast two-hybrid and bimolecular fluorescence complementation assays revealed that BcbHLHpol interacted with BcSKP1 in the nucleus. This finding suggests that BcbHLHpol and BcSKP1 are positive coordinating regulators of pollen development. Quantitative real-time PCR indicated that BcbHLHpol and BcSKP1 can be induced at low temperatures. Thus, we propose that BcbHLHpol is necessary for meiosis. This study provides insights into the regulatory functions of the BcbHLHpol network during anther development. PMID:25147023

  13. Equilibrium Iron Isotope Fractionation Factors of Minerals: Reevaluation from the Data of Nuclear Inelastic Resonant X-ray Scattering and Mossbauer Spectroscopy

    SciTech Connect

    Polyakov, Dr. V. B.; Clayton, R. N.; Horita, Juske; Mineev, S. D.

    2007-01-01

    We have critically reevaluated equilibrium iron isotope fractionation factors for oxide and sulfide minerals using recently acquired data obtained by Moessbauer spectroscopy and inelastic nuclear resonant X-ray scattering (INRXS) synchrotron radiation. Good agreement was observed in the iron {beta}-factors of metallic iron ({alpha}-Fe) and hematite calculated using both Moessbauer- and INRXS-derived data, which supports the validity and reliability of the calculations. Based on this excellent agreement, we suggest the use of the present data on the iron {beta}-factors of hematite as a reference. The previous Moessbauer-derived iron {beta}-factor for magnetite has been modified significantly based on the Fe-sublattice density of states obtained from the INRXS experiments. This resolves the disagreement between naturally observed iron isotope fractionation factors for mineral pairs involving magnetite and those obtained from the calculated {beta}-factors. The correctness of iron {beta}-factor for pyrite has been corroborated by the good agreement with experimental data of sulfur isotope geothermometers of pyrite-galena and pyrite-sphalerite. A good correlation between the potential energy of the cation site, the oxidation state of iron and the iron {beta}-factor value has been established. Specifically, ferric compounds, which have a higher potential energy of iron than ferrous compounds, have higher {beta}-factors. A similar dependence of b-factors on the oxidation state and potential energy could be extended to other transition metals. Extremely low values of INRXS-derived iron {beta}-factors for troilite and Fe{sub 3}S significantly widen the range of iron b-factors for covalently bonded compounds.

  14. A comparative study of small field total scatter factors and dose profiles using plastic scintillation detectors and other stereotactic dosimeters: The case of the CyberKnife

    SciTech Connect

    Morin, J.; Beliveau-Nadeau, D.; Chung, E.; Seuntjens, J.; Theriault, D.; Archambault, L.; Beddar, S.; Beaulieu, L.

    2013-01-15

    Purpose: Small-field dosimetry is challenging, and the main limitations of most dosimeters are insufficient spatial resolution, water nonequivalence, and energy dependence. The purpose of this study was to compare plastic scintillation detectors (PSDs) to several commercial stereotactic dosimeters by measuring total scatter factors and dose profiles on a CyberKnife system. Methods: Two PSDs were developed, having sensitive volumes of 0.196 and 0.785 mm{sup 3}, and compared with other detectors. The spectral discrimination method was applied to subtract Cerenkov light from the signal. Both PSDs were compared to four commercial stereotactic dosimeters by measuring total scatter factors, namely, an IBA dosimetry stereotactic field diode (SFD), a PTW 60008 silicon diode, a PTW 60012 silicon diode, and a microLion. The measured total scatter factors were further compared with those of two independent Monte Carlo studies. For the dose profiles, two commercial detectors were used for the comparison, i.e., a PTW 60012 silicon diode and Gafchromics EBT2. Total scatter factors for a CyberKnife system were measured in circular fields with diameters from 5 to 60 mm. Dose profiles were measured for the 5- and 60-mm cones. The measurements were performed in a water tank at a 1.5-cm depth and an 80-cm source-axis distance. Results: The total scatter factors measured using all the detectors agreed within 1% with the Monte Carlo values for cones of 20 mm or greater in diameter. For cones of 10-20 mm in diameter, the PTW 60008 silicon diode was the only dosimeter whose measurements did not agree within 1% with the Monte Carlo values. For smaller fields (<10 mm), each dosimeter type showed different behaviors. The silicon diodes over-responded because of their water nonequivalence; the microLion and 1.0-mm PSD under-responded because of a volume-averaging effect; and the 0.5-mm PSD was the only detector within the uncertainties of the Monte Carlo simulations for all the cones. The

  15. Monte Carlo simulations of neutron spectral fluence, radiation weighting factor and ambient dose equivalent for a passively scattered proton therapy unit

    NASA Astrophysics Data System (ADS)

    Zheng, Yuanshui; Fontenot, Jonas; Taddei, Phil; Mirkovic, Dragan; Newhauser, Wayne

    2008-01-01

    Stray neutron exposures pose a potential risk for the development of secondary cancer in patients receiving proton therapy. However, the behavior of the ambient dose equivalent is not fully understood, including dependences on neutron spectral fluence, radiation weighting factor and proton treatment beam characteristics. The objective of this work, therefore, was to estimate neutron exposures resulting from the use of a passively scattered proton treatment unit. In particular, we studied the characteristics of the neutron spectral fluence, radiation weighting factor and ambient dose equivalent with Monte Carlo simulations. The neutron spectral fluence contained two pronounced peaks, one a low-energy peak with a mode around 1 MeV and one a high-energy peak that ranged from about 10 MeV up to the proton energy. The mean radiation weighting factors varied only slightly, from 8.8 to 10.3, with proton energy and location for a closed-aperture configuration. For unmodulated proton beams stopped in a closed aperture, the ambient dose equivalent from neutrons per therapeutic absorbed dose (H*(10)/D) calculated free-in-air ranged from about 0.3 mSv/Gy for a small scattered field of 100 MeV proton energy to 19 mSv/Gy for a large scattered field of 250 MeV proton energy, revealing strong dependences on proton energy and field size. Comparisons of in-air calculations with in-phantom calculations indicated that the in-air method yielded a conservative estimation of stray neutron radiation exposure for a prostate cancer patient.

  16. A new SERS: scattering enhanced Raman scattering

    NASA Astrophysics Data System (ADS)

    Bixler, Joel N.; Yakovlev, Vladislav V.

    2014-03-01

    Raman spectroscopy is a powerful technique that can be used to obtain detailed chemical information about a system without the need for chemical markers. It has been widely used for a variety of applications such as cancer diagnosis and material characterization. However, Raman scattering is a highly inefficient process, where only one in 1011 scattered photons carry the needed information. Several methods have been developed to enhance this inherently weak effect, including surface enhanced Raman scattering and coherent anti-Stokes Raman scattering. These techniques suffer from drawbacks limiting their commercial use, such as the need for spatial localization of target molecules to a `hot spot', or the need for complex laser systems. Here, we present a simple instrument to enhance spontaneous Raman scattering using elastic light scattering. Elastic scattering is used to substantially increase the interaction volume. Provided that the scattering medium exhibits very low absorption in the spectral range of interest, a large enhancement factor can be attained in a simple and inexpensive setting. In our experiments, we demonstrate an enhancement of 107 in Raman signal intensity. The proposed novel device is equally applicable for analyzing solids, liquids, and gases.

  17. Metadherin Regulation of Vascular Endothelial Growth Factor Expression Is Dependent Upon the PI3K/Akt Pathway in Squamous Cell Carcinoma of the Head and Neck

    PubMed Central

    Zhu, Gang-cai; Yu, Chang-yun; She, Li; Tan, Hao-lei; Li, Guo; Ren, Su-ling; Su, Zhong-wu; Wei, Ming; Huang, Dong-hai; Tian, Yong-quan; Su, Ri-na; Liu, Yong; Zhang, Xin

    2015-01-01

    Abstract Our previous study indicated overexpression of metadherin (MTDH) is an adverse prognostic factor in squamous cell carcinoma of the head and neck (SCCHN) and promotes SCCHN cell proliferation and invasion. However, its mechanism remains unclear. Recent studies have indicated that MTDH is a cancer-metastasis-associated molecule that participates in the process of angiogenesis. Therefore, the study is aimed to investigate that whether vascular endothelial growth factor (VEGF), as one of the most potent proangiogenic cytokines, is regulated by MTDH and the role of the phosphatidylinositide 3-kinases/Protein Kinase B (PI3K/Akt) pathway in this process of regulation and the clinical significance of both MTDH and VEGF in SCCHN. Immunohistochemistry was used to assay the expression of MTDH and VEGF in a cohort of 189 SCCHN patients with intact follow-up information. The expression of MTDH was then upregulated or inhibited by lentivirus-mediated MTDH Complementary deoxyribonucleic acid or MTDH short hairpin ribonucleic acid (shRNA) to observe the resulting alterations in VEGF expression and the PI3K/Akt signaling pathway in SCCHN cell lines. In addition, the PI3K/Akt pathway was modulated to observe the resulting changes in the MTDH-mediated expression of VEGF. The immunohistochemistry data showed that MTDH expression is positively correlated with VEGF expression in SCCHN tissues. Moreover, the overexpression of MTDH in SCCHN Tu686 and 5-8F cells led to increases in the expression of VEGF, and this effect was accompanied by activation of the PI3K/Akt pathway. Conversely, shRNA-mediated knockdown of MTDH led to decreased VEGF expression. In addition, inhibition of the Akt signaling pathway reversed the upregulation of VEGF resulting from MTDH overexpression. Moreover, the survival analysis revealed that VEGF is an independent prognostic factor, and a combined survival analysis based on both MTDH and VEGF showed synergistic effects in the prognosis evaluation of

  18. Metadherin regulation of vascular endothelial growth factor expression is dependent upon the PI3K/Akt pathway in squamous cell carcinoma of the head and neck.

    PubMed

    Zhu, Gang-Cai; Yu, Chang-Yun; She, Li; Tan, Hao-Lei; Li, Guo; Ren, Su-Ling; Su, Zhong-Wu; Wei, Ming; Huang, Dong-Hai; Tian, Yong-Quan; Su, Ri-Na; Liu, Yong; Zhang, Xin

    2015-02-01

    Our previous study indicated overexpression of metadherin (MTDH) is an adverse prognostic factor in squamous cell carcinoma of the head and neck (SCCHN) and promotes SCCHN cell proliferation and invasion. However, its mechanism remains unclear. Recent studies have indicated that MTDH is a cancer-metastasis-associated molecule that participates in the process of angiogenesis. Therefore, the study is aimed to investigate that whether vascular endothelial growth factor (VEGF), as one of the most potent proangiogenic cytokines, is regulated by MTDH and the role of the phosphatidylinositide 3-kinases/Protein Kinase B (PI3K/Akt) pathway in this process of regulation and the clinical significance of both MTDH and VEGF in SCCHN.Immunohistochemistry was used to assay the expression of MTDH and VEGF in a cohort of 189 SCCHN patients with intact follow-up information. The expression of MTDH was then upregulated or inhibited by lentivirus-mediated MTDH Complementary deoxyribonucleic acid or MTDH short hairpin ribonucleic acid (shRNA) to observe the resulting alterations in VEGF expression and the PI3K/Akt signaling pathway in SCCHN cell lines. In addition, the PI3K/Akt pathway was modulated to observe the resulting changes in the MTDH-mediated expression of VEGF.The immunohistochemistry data showed that MTDH expression is positively correlated with VEGF expression in SCCHN tissues. Moreover, the overexpression of MTDH in SCCHN Tu686 and 5-8F cells led to increases in the expression of VEGF, and this effect was accompanied by activation of the PI3K/Akt pathway. Conversely, shRNA-mediated knockdown of MTDH led to decreased VEGF expression. In addition, inhibition of the Akt signaling pathway reversed the upregulation of VEGF resulting from MTDH overexpression. Moreover, the survival analysis revealed that VEGF is an independent prognostic factor, and a combined survival analysis based on both MTDH and VEGF showed synergistic effects in the prognosis evaluation of SCCHN patients

  19. Head Lice

    MedlinePlus

    ... Treatment FAQs Malathion FAQs Epidemiology & Risk Factors Disease Biology Diagnosis Treatment Prevention & Control Resources for Health Professionals ... Frequently Asked Questions (FAQs) Epidemiology & Risk Factors Disease Biology Diagnosis Treatment Prevention & Control Resources for Health Professionals ...

  20. Integrating Epidermal Growth Factor Receptor Assay With Clinical Parameters Improves Risk Classification for Relapse and Survival in Head-and-Neck Squamous Cell Carcinoma

    SciTech Connect

    Chung, Christine H.; Hammond, Elizabeth M.; Trotti, Andy M.; Wang Huijun; Spencer, Sharon; Zhang Huazhong; Cooper, Jay; Jordan, Richard; Rotman, Marvin H.; Ang, K. Kian

    2011-10-01

    Purpose: Epidermal growth factor receptor (EGFR) overexpression has been consistently found to be an independent predictor of local-regional relapse (LRR) after radiotherapy. We assessed the extent by which it can refine risk classification for overall survival (OS) and LRR in patients with head-and-neck squamous cell carcinoma (HNSCC). Methods and Materials: EGFR expression in locally advanced HNSCC was measured by immunohistochemistry in a series of patients randomized to receive accelerated or conventional radiation regimens in a Phase III trial. Subsequently, data of the two series were pooled (N = 533) for conducting a recursive partitioning analysis that incorporated clinical parameters (e.g., performance status, primary site, T and N categories) and four molecular markers (EGFR, p53, Ki-67, and microvessel density). Results: This study confirmed that patients with higher than median levels of tumor EGFR expression had a lower OS (relative risk [RR]: 1.90, p = 0.0010) and a higher LRR (RR: 1.91, p = 0.0163). Of the four markers analyzed, only EGFR was found to contribute to refining classification of patients into three risk classes with distinct OS and LRR outcomes. The addition of EGFR to three clinical parameters could identify patients having up to a fivefold difference in the risk of LRR. Conclusions: Adding pretreatment EGFR expression data to known robust clinical prognostic variables improved the estimation of the probability for OS and LRR after radiotherapy. Its use for stratifying or selecting patients with defined tumor feature and pattern of relapse for enrollment into clinical trials testing specific therapeutic strategy warrants further investigation.

  1. Novel Immunogenic HLA-A*0201-restricted Epidermal Growth Factor Receptor-specific T-cell Epitope in Head and Neck Cancer Patients

    PubMed Central

    Andrade Filho, Pedro A.; López-Albaitero, Andrés; Gooding, William; Ferris, Robert L.

    2013-01-01

    Summary Therapeutic targeting of the epidermal growth factor receptor (EGFR), which is highly overexpressed and correlated with poor prognosis in colorectal and head and neck squamous cell carcinoma (SCCHN), has shown clinical efficacy using the blocking mAbs, cetuximab or panitumumab, but only in 10% to 20% of patients. Clinical responsiveness is correlated with certain Fcγ receptor genotypes, suggesting immune activity may contribute to therapeutic efficacy. In addition, cetuximab-resistant tumor cells exhibit ubiquitination and degradation of EGFR, which would increase its processing as a tumor antigen for cytotoxic T lymphocyte (CTL) lysis. Thus, T cell-based immunotherapy might enhance the antitumor efficacy of EGFR-specific mAbs, but CTL epitopes are poorly defined. To permit combinatorial EGFR-targeted immunotherapy, we identified a novel immunogenic wild-type sequence peptide, EGFR853 – 861 and modified its anchor sequence to enhance HLA-A*0201 binding and stimulation of cross-reactive anti-wild–type EGFR853 – 861-specific CTL. Cross-reactivity was also observed with HER2861 – 869. EGFR853 – 861-specific CTL recognition of SCCHN cells was increased by incubation of tumor cells with cetuximab, which led to EGFR degradation. In addition, EGFR853 – 861-specific CTLs were elevated in the circulation of SCCHN patients as compared with healthy control peripheral blood mononuclear cells. Thus, a novel, immunogenic EGFR-encoded CTL epitope may be incorporated into vaccines and would be useful for combinatorial immunotherapy with EGFR-specific mAbs in cancer patients. PMID:19952953

  2. Effects of spaceflight on the murine mandible: Possible factors mediating skeletal changes in non-weight bearing bones of the head.

    PubMed

    Ghosh, Payal; Stabley, John N; Behnke, Bradley J; Allen, Matthew R; Delp, Michael D

    2016-02-01

    Spaceflight-induced remodeling of the skull is characterized by greater bone volume, mineral density, and mineral content. To further investigate the effects of spaceflight on other non-weight bearing bones of the head, as well as to gain insight into potential factors mediating the remodeling of the skull, the purpose of the present study was to determine the effects of spaceflight on mandibular bone properties. Female C57BL/6 mice were flown 15d on the STS-131 Space Shuttle mission (n=8) and 13d on the STS-135 mission (n=5) or remained as ground controls (GC). Upon landing, mandibles were collected and analyzed via micro-computed tomography for tissue mineralization, bone volume (BV/TV), and distance from the cemento-enamel junction to the alveolar crest (CEJ-AC). Mandibular mineralization was not different between spaceflight (SF) and GC mice for either the STS-131 or STS-135 missions. Mandibular BV/TV (combined cortical and trabecular bone) was lower in mandibles from SF mice on the STS-131 mission (80.7±0.8%) relative to that of GC (n=8) animals (84.2±1.2%), whereas BV/TV from STS-135 mice was not different from GC animals (n=7). The CEJ-AC distance was shorter in mandibles from STS-131 mice (0.217±0.004mm) compared to GC animals (0.283±0.009mm), indicating an anabolic (or anti-catabolic) effect of spaceflight, while CEJ-AC distance was similar between STS-135 and GC mice. These findings demonstrate that mandibular bones undergo skeletal changes during spaceflight and are susceptible to the effects of weightlessness. However, adaptation of the mandible to spaceflight is dissimilar to that of the cranium, at least in terms of changes in BV/TV. PMID:26545335

  3. Development of receptors for insulin and insulin-like growth factor-I in head and brain of chick embryos: Autoradiographic localization

    SciTech Connect

    Bassas, L.; Girbau, M.; Lesniak, M.A.; Roth, J.; de Pablo, F. )

    1989-11-01

    In whole brain of chick embryos insulin receptors are highest at the end of embryonic development, while insulin-like growth factor-I (IGF-I) receptors dominate in the early stages. These studies provided evidence for developmental regulation of both types of receptors, but they did not provide information on possible differences between brain regions at each developmental stage or within one region at different embryonic ages. We have now localized the specific binding of (125I)insulin and (125I)IGF-I in sections of head and brain using autoradiography and computer-assisted densitometric analysis. Embryos have been studied from the latter part of organogenesis (days 6 and 12) through late development (day 18, i.e. 3 days before hatching), and the binding patterns have been compared with those in the adult brain. At all ages the binding of both ligands was to discrete anatomical regions. Interestingly, while in late embryos and adult brain the patterns of (125I)insulin and (125I) IGF-I binding were quite distinct, in young embryos both ligands showed very similar localization of binding. In young embryos the retina and lateral wall of the growing encephalic vesicles had the highest binding of both (125I)insulin and (125I)IGF-I. In older embryos, as in the adult brain, insulin binding was high in the paleostriatum augmentatum and molecular layer of the cerebellum, while IGF-I binding was prominent in the hippocampus and neostriatum. The mapping of receptors in a vertebrate embryo model from early prenatal development until adulthood predicts great overlap in any possible function of insulin and IGF-I in brain development, while it anticipates differential localized actions of the peptides in the mature brain.

  4. WAX INDUCER1 (HvWIN1) transcription factor regulates free fatty acid biosynthetic genes to reinforce cuticle to resist Fusarium head blight in barley spikelets.

    PubMed

    Kumar, Arun; Yogendra, Kalenahalli N; Karre, Shailesh; Kushalappa, Ajjamada C; Dion, Yves; Choo, Thin M

    2016-07-01

    Fusarium head blight (FHB), caused by Fusarium graminearum, is one of the most devastating diseases of wheat and barley. Resistance to FHB is highly complex and quantitative in nature, and is most often classified as resistance to spikelet infection and resistance to spread of pathogen through the rachis. In the present study, a resistant (CI9831) and a susceptible (H106-371) two-row barley genotypes, with contrasting levels of spikelet resistance to FHB, pathogen or mock-inoculated, were profiled for metabolites based on liquid chromatography and high resolution mass spectrometry. The key resistance-related (RR) metabolites belonging to fatty acids, phenylpropanoids, flavonoids and terpenoid biosynthetic pathways were identified. The free fatty acids (FFAs) linoleic and palmitic acids were among the highest fold change RR induced (RRI) metabolites. These FFAs are deposited as cutin monomers and oligomers to reinforce the cuticle, which acts as a barrier to pathogen entry. Quantitative real-time PCR studies revealed higher expressions of KAS2, CYP86A2, CYP89A2, LACS2 and WAX INDUCER1 (HvWIN1) transcription factor in the pathogen-inoculated resistant genotype than in the susceptible genotype. Knockdown of HvWIN1 by virus-induced genes silencing (VIGS) in resistant genotype upon pathogen inoculation increased the disease severity and fungal biomass, and decreased the abundance of FFAs like linoleic and palmitic acids. Notably, the expression of CYP86A2, CYP89A2 and LAC2 genes was also suppressed, proving the link of HvWIN1 in regulating these genes in cuticle biosynthesis as a defense response. PMID:27194736

  5. Monopole-antimonopole scattering

    NASA Astrophysics Data System (ADS)

    Vachaspati, Tanmay

    2016-02-01

    We numerically study the head-on scattering of a 't Hooft-Polyakov magnetic monopole and antimonopole for a wide range of parameters. In contrast to the scattering of a λ ϕ4 kink and antikink in 1 +1 dimensions, we find that the monopole and antimonopole annihilate even when scattered at relativistic velocities. If the monopole and antimonopole have a relative twist, there is a repulsive force between them and they can initially be reflected. However, in every case we have examined, the reflected monopoles remain bound and eventually annihilate. We also calculate the magnetic helicity in the aftermath of monopole-antimonopole annihilation and confirm the conversion of relative twist to magnetic helicity as discussed earlier in the electroweak case.

  6. Dynamic structure factor for large aggregate clusters with internal motions: a self-consistent light-scattering study on conjugated polymer solutions.

    PubMed

    Wen, Yu H; Lin, Po C; Hua, Chi C; Chen, Show A

    2011-12-15

    The aggregation properties of a standard conjugated polymer, poly(2-methoxy-5-(2'-ethylhexyloxy)-1,4-phenylenevinylene) (MEH-PPV), in two distinct solvents (chloroform and toluene) and a range of polymer concentrations (c = 0.1-3 mg/mL) have been unequivocally resolved using combined dynamic and static light scatterings (DLS/SLS). The prime challenges for analyzing this peculiar, practically important, solution system arise from the wide size distribution and unknown aggregate morphology, as well as pronounced interferences between translational and internal motions of aggregate clusters of considerably varying size. To cope with these central difficulties, we propose a self-consistent formulation for analyzing the dynamic structure factor in DLS experiment by extending an existing theory on free-draining bead-spring chains that explicitly accounts for internal fluctuations, along with two candidate form factors on Gaussian coil and rigid sphere, respectively, serving as two limiting cases to be discriminated in combined DLS and SLS measurements. Given that no accessibility to ultrasmall angular resolutions is a prerequisite, the suggested protocol can readily be carried out in conventional light-scattering apparatus. The present analyses unanimously support the rigid-sphere form factor in describing the entire set of light-scattering data on MEH-PPV solutions, differing from early small-angle neutron/X-ray scattering interpretations suggesting certain 2D fractal structures for the aggregation network. Scrutiny into the interior dynamics of aggregate clusters further disclosed that the segmental motions are noticeably more suppressed than for usual, nonaggregated polymer solutions, and no existing theories based on the bead-spring picture can yet capture the observed scaling behavior as manifested by the present data. Accordingly, we report several first-revealed properties of MEH-PPV solutions on the aggregate morphology, the size distribution (and mean size

  7. Heading in Soccer: Integral Skill or Grounds for Cognitive Dysfunction?

    ERIC Educational Resources Information Center

    Kirkendall, Donald T.; Garrett, William E., Jr.

    2001-01-01

    Discusses how purposeful heading of soccer balls and head injuries affect soccer players' cognitive dysfunction. Cognitive deficits may occur for many reasons. Heading cannot be blamed when details of the actual event and impact are unknown. Concussions are the most common head injury in soccer and a factor in cognitive deficits and are probably…

  8. Possible arrangement of the five domains in human complement factor I as determined by a combination of X-ray and neutron scattering and homology modeling.

    PubMed

    Chamberlain, D; Ullman, C G; Perkins, S J

    1998-10-01

    Human factor I is a multidomain plasma serine protease with one factor I-membrane attack complex (FIMAC) domain, one CD5 domain, two low-density lipoprotein receptor (LDLr) domains, and one serine protease (SP) domain and is essential for the regulation of complement. The domain arrangement in factor I was determined by X-ray and neutron scattering on serum-derived human factor I (sFI) and recombinant insect cell factor I (rFI). While the radii of gyration of both were the same at 4.05 nm and both had overall lengths of 14 nm, the cross-sectional radii of gyration were different at 1.70 nm for sFI and 1.57 nm for rFI. This difference was attributed to their different means of glycosylation which is complex-type for sFI and high-mannose-type for rFI. Homology models were constructed for the FIMAC, LDLr, and SP domains of factor I using related crystal structures, and CD5 was represented as a globular protein by referencing its electron microscopy dimensions. In these models, 38 of the 40 Cys residues in factor I were predicted to form internal disulfide bridges. The two remaining Cys residues at the N terminus of the FIMAC domain and at the center of the first LDLr domain were potentially not bridged. It was postulated that, if these two Cys residues were bridged to each other, the FIMAC, CD5, and LDLr-1 domains would form a compact triangular arrangement. This hypothesis was tested by automated scattering curve fit searches based on 9600 bilobal models, setting the FIMAC, CD5, and LDLr-1 domains as one lobe and the large SP domain as the other lobe. The searches gave a single small family of similar structures with a separation of 5.9 nm between the centers of the lobes which gave similar good X-ray and neutron fits for both sFI and rFI, despite the different glycosylations of sFI and rFI. These best-fit structures for factor I showed that this domain model is plausible, and suggested that the SP and the CD5 and LDLr-1 domains may present exposed surfaces in factor

  9. Abnormal Head Position

    MedlinePlus

    ... cause. Can a longstanding head turn lead to any permanent problems? Yes, a significant abnormal head posture could cause permanent ... occipitocervical synostosis and unilateral hearing loss. Are there any ... postures? Yes. Abnormal head postures can usually be improved depending ...

  10. Head and face reconstruction

    MedlinePlus

    Head and face reconstruction is surgery to repair or reshape deformities of the head and face (craniofacial). ... How surgery for head and face deformities (craniofacial reconstruction) ... and the person's condition. Surgical repairs involve the ...

  11. Head circumference (image)

    MedlinePlus

    Head circumference is a measurement of the circumference of the child's head at its largest area (above the eyebrows and ears and around the back of the head). During routine check-ups, the distance is measured ...

  12. Head Injury Prevention Tips

    MedlinePlus

    Head Injury Prevention Tips American Association of Neurological Surgeons 5550 Meadowbrook Drive, Rolling Meadows, IL 60008-3852 ... defined as a blow or jolt to the head or a penetrating head injury that disrupts the ...

  13. SU-E-T-246: MU Model Implementation for a Passively Scattered Proton Beam: Inclusion of the Bolus Gap and Nozzle Extension Factors

    SciTech Connect

    Simpson, R; Ghebremedhin, A; Gordon, I; Patyal, B; Piskulich, F.; LeMaster, Brett

    2014-06-01

    Purpose: To develop and implement an MU model for a passively scattered proton beam, and eliminate the need for patient specific calibrations for field sizes from 3cm to 15cm. This would enable consistent and timely calibrations for a wide variety of patient portals, streamlining the treatment process. Methods: Measurements were initially made using a Standard Imaging A-16 ion chamber and a modified water tank to determine the bolus gap factors (BGF) for multiple combinations of aperture size, bolus thickness, and air gap. The BGF was then separated into two component factors: the bolus thickness factor (BTF) and the nozzle extension factor (NEF). Polynomial curves were generated using the measured data to produce BTF tables for air gaps from 0cm to 30cm and for bolus thicknesses from 0cm to 10cm, and NEF tables for the full range of clinically used nozzle extensions. Additionally, data tables were created for every factor that affects beam output in the MU model. The MUs were then modeled for 487 patient portals and retrospectively compared to the MUs generated from the physical calibrations previously performed. Results: Of the 487 patient portals tested, 100% of the portals used for the comparison were within 2.5% from the MUs generated using a physical calibration, and 95.9% of the MU model portals tested were within 2%. The patient portals tested had field sizes ranging from 2.1cm to 10.1cm, with air gaps from 2cm to 25cm. Output factors for field sizes below 3cm with irregularly shaped fields demonstrated inconsistent results and will be further studied. Conclusion: The most problematic output factor, the BGF, was modeled accurately and consistently using the lowest order polynomial curve fits and interpolation between measured data. The study results demonstrate the robustness of the MU model and the potential for saving valuable personnel and beam time.

  14. Building Successful Home Visitor-Mother Relationships and Reaching Program Goals in Two Early Head Start Programs: A Qualitative Look at Contributing Factors

    ERIC Educational Resources Information Center

    Brookes, Sheila J.; Summers, Jean Ann; Thornburg, Kathy R.; Ispa, Jean M.; Lane, Valeri J.

    2006-01-01

    This paper presents the results of two qualitative studies, conducted independently in two Early Head Start programs, exploring the reasons given by mothers and home visitors for family success or lack of success in achieving program goals and for engagement in the mother-home visitor relationship. Several patterns pertaining to family issues and…

  15. Distinct Factors Associated with Head Start Mothers' Self-Report of Perceived Low Positive and High Negative Maternal Expressiveness

    ERIC Educational Resources Information Center

    Edwards, Nicole Megan

    2014-01-01

    Research Findings: There is growing acknowledgment of the need for parenting interventions to address early-onset behavior and emotional concerns. Favorable child outcomes have been linked to parents' responsiveness and positive expressiveness. Given the theoretical and empirical link between perceptions and actual behavior, Head Start…

  16. Small-angle neutron scattering study of pH dependence of the liquid structure factor of concentrated solutions of eye lens gamma-B crystallin

    NASA Astrophysics Data System (ADS)

    Desmond, Kenneth; Thurston, George; Stradner, Anna; Schurtenberger, Peter

    2006-03-01

    We are evaluating the pH dependence of the liquid structure of aqueous solutions of the eye lens protein, gammaB crystallin, near its critical point for liquid-liquid phase separation, to help evaluate the influence of protein charge on the phase separation. We have obtained small-angle neutron scattering data from gammaB crystallin solutions at pH 6.4, 7.1 and 7.4 in a 0.1 M sodium phosphate buffer, and at pH 4.5 in a 0.020M sodium acetate buffer, all in D2O. Protein concentrations ranged from 6 to 260 mg protein/ml solution and the scattering vector magnitude (q) ranged from 0.004 to 0.45 inverse Angstroms. At pH 6.4 to 7.4 liquid structure factors vs. concentration and temperature near the cloud point for liquid-liquid phase separation are well represented, in general, by the Baxter sticky sphere model. In contrast, at pH 4.5, concentrated gammaB shows a very different liquid structure indicating highly repulsive interprotein interactions, consistent with both high net protein charge and reduced screening.

  17. High Surface-Enhanced Raman Scattering (SERS) Amplification Factor Obtained with Silver Printed Circuit Boards and the Influence of Phenolic Resins for the Characterization of the Pesticide Thiram.

    PubMed

    Silva de Almeida, Francylaine; Bussler, Larissa; Marcio Lima, Sandro; Fiorucci, Antonio Rogério; da Cunha Andrade, Luis Humberto

    2016-07-01

    In this work, low-cost substrates with rough silver surfaces were prepared from commercial copper foil-covered phenolic board (CPB) and an aqueous solution of AgNO3, and were used for surface-enhanced Raman scattering (SERS) and surface-enhanced resonance Raman scattering (SERRS) measurements. A maximum SERS amplification factor of 1.2 × 10(7) was obtained for Rhodamine 6G (R6G), and use of the CPB resulted in a detection limit for Thiram pesticide of 0.5 µmol L(-1) The minimum detection level was limited by residual traces of phenolic groups that originated from the substrate resin, which became solubilized in the aqueous Ag(+) solution. It was found that the bands corresponding to the impurities had less influence in the Thiram analysis, which could be explained by the high affinity of sulfur for Ag surfaces. The influence of impurities in the SERS analyses therefore depended on the linkage between the rough silver surface and the analyte. The findings demonstrated the ease and effectiveness of using CPB to prepare a nanostructured surface for SERS. PMID:27279502

  18. Aureolegraph internal scattering correction.

    PubMed

    DeVore, John; Villanucci, Dennis; LePage, Andrew

    2012-11-20

    Two methods of determining instrumental scattering for correcting aureolegraph measurements of particulate solar scattering are presented. One involves subtracting measurements made with and without an external occluding ball and the other is a modification of the Langley Plot method and involves extrapolating aureolegraph measurements collected through a large range of solar zenith angles. Examples of internal scattering correction determinations using the latter method show similar power-law dependencies on scattering, but vary by roughly a factor of 8 and suggest that changing aerosol conditions during the determinations render this method problematic. Examples of corrections of scattering profiles using the former method are presented for a range of atmospheric particulate layers from aerosols to cumulus and cirrus clouds. PMID:23207299

  19. A Preliminary Report on X-Ray Photoabsorption Coefficients andAtomic Scattering Factors for 92 Elements in the 10-10,000 eVRegion

    SciTech Connect

    Henke, B.L.; Davis, J.C.; Gullikson, E.M.; Perera, R.C.C.

    1988-11-01

    Based on currently available photoabsorption measurements and recent theoretical calculations by Doolen and Liberman (Physica Scripta 36, 77 (1987)), a revised (from ADNDT 27, 1 (1982)) best-fit determination of the photoabsorption cross sections is presented here for the elements Z=1 to Z=92 in the 10-10,000 eV range. The photoabsorption data used include those described in the Lockheed and DOE listings of research abstracts for the past ten years and those which have been recently added to the comprehensive NBS Measured Data Base (NBSIR 86-3461, Hubbell et al.). The best-fit curves are compared with both the compilation of measurements and the calculations by Doolen and Liberman. Using the photoabsorption curves, the atomic scattering factors have been calculated for the energy range 50-10,000 eV and are also presented in this report.

  20. Lidar multiple scattering factors inferred from CALIPSO lidar and IIR retrievals of semi-transparent cirrus cloud optical depths over oceans

    NASA Astrophysics Data System (ADS)

    Garnier, A.; Pelon, J.; Vaughan, M. A.; Winker, D. M.; Trepte, C. R.; Dubuisson, P.

    2015-07-01

    Cirrus cloud absorption optical depths retrieved at 12.05 μm are compared to extinction optical depths retrieved at 0.532 μm from perfectly co-located observations of single-layered semi-transparent cirrus over ocean made by the Imaging Infrared Radiometer (IIR) and the Cloud and Aerosol Lidar with Orthogonal Polarization (CALIOP) flying on board the CALIPSO (Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observations) satellite. IIR infrared absorption optical depths are compared to CALIOP visible extinction optical depths when the latter can be directly derived from the measured apparent two-way transmittance through the cloud. An evaluation of the CALIOP multiple scattering factor is inferred from these comparisons after assessing and correcting biases in IIR and CALIOP optical depths reported in version 3 data products. In particular, the blackbody radiance taken in the IIR version 3 algorithm is evaluated, and IIR retrievals are corrected accordingly. Numerical simulations and IIR retrievals of ice crystal sizes suggest that the ratios of CALIOP extinction and IIR absorption optical depths should remain roughly constant with respect to temperature. Instead, these ratios are found to increase quasi-linearly by about 40 % as the temperature at the layer centroid altitude decreases from 240 to 200 K. It is discussed that this behavior can be explained by variations of the multiple scattering factor ηT applied to correct the measured apparent two-way transmittance for contribution of forward-scattering. While the CALIOP version 3 retrievals hold ηT fixed at 0.6, this study shows that ηT varies with temperature (and hence cloud particle size) from ηT = 0.8 at 200 K to ηT = 0.5 at 240 K for single-layered semi-transparent cirrus clouds with optical depth larger than 0.3. The revised parameterization of ηT introduces a concomitant temperature dependence in the simultaneously derived CALIOP lidar ratios that is consistent with observed changes in CALIOP

  1. SU-E-T-72: Commissioning of a Standardized SRS Cone Set: Determination of the Bolus Gap Factors in a Passively Scattered Proton Beam

    SciTech Connect

    Simpson, R; Gordon, I; Ghebremedhin, A; Wroe, A; Schulte, R; Bush, D; Slater, J; Patyal, B

    2014-06-01

    Purpose: To determine the proton output factors for an SRS cone set using standardized apertures and varied range compensators (bolus blanks); specifically, to determine the best method for modeling the bolus gap factor (BGF) and eliminate the need for patient specific calibrations. Methods: A Standard Imaging A-16 chamber was placed in a Plastic Water phantom to measure the change in dose/MU with different treatment combinations for a proton SRS cone, using standardized apertures and range compensators. Measurements were made with all apertures in the SRS cone set, with four different range compensator thicknesses and five different air gaps between the end of the SRS cone and the surface of the phantom. The chamber was located at iso-center and maintained at a constant depth at the center of modulation for all measurements. Each aperture was placed in the cone to measure the change in MU needed to maintain constant dose at the chamber, as the air gap was increased with different thicknesses of bolus. Results: The dose/MU varied significantly with decreasing aperture size, increasing bolus thickness, or increasing air gap. The measured data was fitted with the lowest order polynomials that accurately described the data, to create a model for determining the change in output for any potential combination of devices used to treat a patient. For a given standardized aperture, the BGF could be described by its constituent factors: the bolus thickness factor (BTF) and the nozzle extension factor (NEF). Conclusion: The methods used to model the dose at the calibration point could be used to accurately predict the change in output for SRS proton beams due to the BGF, eliminating the need for patient specific calibrations. This method for modeling SRS treatments could also be applied to model other treatments using passively scattered proton beams.

  2. Risk Factors for Femoral Head Deformity in the Early Stage of Legg-Calvé-Perthes Disease: MR Contrast Enhancement and Diffusion Indexes.

    PubMed

    Yoo, Won Joon; Choi, In Ho; Cho, Tae-Joon; Jang, Wooyoung; Chung, Chin Youb; Park, Moon Seok; Choi, Eun-Seok; Cheon, Jung-Eun

    2016-05-01

    Purpose To determine whether changes in diffusion and/or contrast enhancement are of prognostic value in the early stage of Legg-Calvé-Perthes disease (LCPD). Materials and Methods This study was approved by the institutional review board, and written informed consent was obtained from patient parents. Diffusion and contrast agent-enhanced magnetic resonance (MR) imaging studies were performed in 46 children (37 boys and nine girls; mean age, 7.5 years [age range, 3.3-11.9 years]) with unilateral LCPD at the early stage before development of extensive femoral head deformity. The degree of contrast enhancement was measured on the contrast-enhanced MR images, and the apparent diffusion coefficient (ADC) value was measured on the ADC map at various regions of interest in the proximal femur. The association of the MR imaging parameters that compared the affected side with the contralateral normal side with the femoral head deformity index value above 0.3 at 2 years was investigated. Results Increased diffusion in the metaphysis (P = .003) and decreased contrast enhancement in the central epiphysis (P = .034) were the significant prognostic indicators of subsequent femoral head deformation. ADC in the metaphysis 45% higher and a contrast enhancement in the central epiphysis 37% lower than those of the contralateral normal side are associated with a nonfavorable prognosis. For diffusion MR imaging, sensitivity was 83% (15 of 18), specificity was 86% (24 of 28), positive predictive value was 79% (15 of 19), negative predictive value was 89% (24 of 27), and accuracy was 85% (39 of 46). For contrast-enhanced MR imaging, sensitivity was 78% (14 of 18), specificity was 64% (18 of 28), positive predictive value was 58% (14 of 24), negative predictive value was 82% (18 of 22), and accuracy was 70% (32 of 46). Conclusion Diffusion and contrast-enhanced MR imaging are potentially useful to assess risk of later development of femoral head deformity. (©) RSNA, 2015. PMID:26606039

  3. Head nurse or hotel manager?

    PubMed

    McAlvanah, M

    1989-01-01

    The responsibility of making room assignments for patients can be both a challenging and frustrating experience for a head nurse. Many factors must be considered when making room assignments while consumer dissatisfaction with the process must be handled creatively and with understanding. PMID:2734042

  4. Next-to-leading order QCD factorization for semi-inclusive deep inelastic scattering at twist 4.

    PubMed

    Kang, Zhong-Bo; Wang, Enke; Wang, Xin-Nian; Xing, Hongxi

    2014-03-14

    Within the framework of a high-twist approach, we calculate the next-to-leading order (NLO) perturbative QCD corrections to the transverse momentum broadening in semi-inclusive hadron production in deeply inelastic e+A collisions, as well as lepton pair production in p+A collisions. With explicit calculations of both real and virtual contributions, we verify, for the first time, the factorization theorem at twist 4 in NLO for the nuclear-enhanced transverse momentum weighted differential cross section and demonstrate the universality of the associated twist-4 quark-gluon correlation function. We also identify the QCD evolution equation for the twist-4 quark-gluon correlation function in a large nucleus, which can be solved to determine the scale dependence of the jet transport parameter in the study of jet quenching. PMID:24679281

  5. Next-to-Leading Order QCD Factorization for Semi-Inclusive Deep Inelastic Scattering at Twist 4

    NASA Astrophysics Data System (ADS)

    Kang, Zhong-Bo; Wang, Enke; Wang, Xin-Nian; Xing, Hongxi

    2014-03-01

    Within the framework of a high-twist approach, we calculate the next-to-leading order (NLO) perturbative QCD corrections to the transverse momentum broadening in semi-inclusive hadron production in deeply inelastic e +A collisions, as well as lepton pair production in p +A collisions. With explicit calculations of both real and virtual contributions, we verify, for the first time, the factorization theorem at twist 4 in NLO for the nuclear-enhanced transverse momentum weighted differential cross section and demonstrate the universality of the associated twist-4 quark-gluon correlation function. We also identify the QCD evolution equation for the twist-4 quark-gluon correlation function in a large nucleus, which can be solved to determine the scale dependence of the jet transport parameter in the study of jet quenching.

  6. Immunohistochemical detection of osteopontin in advanced head-and-neck cancer: Prognostic role and correlation with oxygen electrode measurements, hypoxia-inducible-factor-1{alpha}-related markers, and hemoglobin levels

    SciTech Connect

    Bache, Matthias; Reddemann, Rolf; Said, Harun M.; Holzhausen, Hans-Juergen; Taubert, Helge; Becker, Axel; Kuhnt, Thomas; Haensgen, Gabriele; Dunst, Juergen; Vordermark, Dirk . E-mail: vordermark_d@klinik.uni-wuerzburg.de

    2006-12-01

    Purpose: The tumor-associated glycoprotein osteopontin (OPN) is discussed as a plasma marker of tumor hypoxia. However, the association of immunohistochemical OPN expression in tumor sections with tumor oxygenation parameters (HF5, median pO{sub 2}), the hypoxia-related markers hypoxia-inducible factor-1{alpha} (HIF-1{alpha}) and carbonic anhydrase IX (CAIX), or hemoglobin and systemic vascular endothelial growth factor (VEGF) levels has not been investigated. Methods and Materials: Tumor tissue sections of 34 patients with advanced head-and-neck cancer treated with radiotherapy were assessed by immunochemistry for the expression of OPN, HIF-1{alpha}, and CA IX. Relationship of OPN expression with tumor oxygenation parameters (HF5, median pO{sub 2}), HIF-1{alpha} and CA IX expression, hemoglobin and serum VEGF level, and clinical parameters was studied. Results: Bivariate analysis showed a significant correlation of positive OPN staining with low hemoglobin level (p = 0.02), high HIF-1{alpha} expression (p = 0.02), and high serum vascular endothelial growth factor level (p = 0.02) for advanced head-and-neck cancer. Furthermore, considering the 31 Stage IV patients, the median pO{sub 2} correlated significantly with the OPN expression (p = 0.02). OPN expression alone had only a small impact on prognosis. However, in a univariate Cox proportional hazard regression model, the expression of either OPN or HIF-1{alpha} or CA IX was associated with a 4.1-fold increased risk of death (p = 0.02) compared with negativity of all three markers. Conclusion: Osteopontin expression detected immunohistochemically is associated with oxygenation parameters in advanced head-and-neck cancer. When the results of OPN, HIF-1{alpha}, and CA IX immunohistochemistry are combined into a hypoxic profile, a strong and statistically significant impact on overall survival is found.

  7. Involvement of activator protein 1 complexes in the epithelium-specific activation of the laminin gamma2-chain gene promoter by hepatocyte growth factor (scatter factor).

    PubMed Central

    Olsen, J; Lefebvre, O; Fritsch, C; Troelsen, J T; Orian-Rousseau, V; Kedinger, M; Simon-Assmann, P

    2000-01-01

    Laminin-5 is a trimer of laminin alpha3, beta3 and gamma2 chains that is found in the intestinal basement membrane. Deposition of the laminin gamma2 chain at the basement membrane is of great interest because it undergoes a developmental shift in its cellular expression. Here we study the regulatory elements that control basal and cytokine-activated transcriptional expression of the LAMC2 gene, which encodes the laminin gamma2 chain. By using transient transfection experiments we demonstrated the presence of constitutive and cytokine-responsive cis-elements. Comparison of the transcriptional activity of the LAMC2 promoter in the epithelial HT29mtx cells with that in small-intestinal fibroblastic cells (C20 cells) led us to conclude that two regions with constitutive epithelium-specific activity are present between positions -1.2 and -0.12 kb. This was further validated by transfections of primary foetal intestinal endoderm and mesenchyme. A 2.5 kb portion of the LAMC2 5' flanking region was equally responsive to PMA and hepatocyte growth factor (HGF), whereas it was less responsive to transforming growth factor beta1. A minimal promoter limited to the initial 120 bp upstream of the transcriptional start site maintained inducibility by PMA and HGF. This short promoter fragment contains two activator protein 1 (AP-1) elements and the 5'-most of these is a composite AP-1/Sp1 element. The 5'AP-1 element is crucial to the HGF-mediated activity of the promoter; analysis of interacting nuclear proteins demonstrated that AP-1 proteins containing JunD mediate the response to HGF. PMID:10749670

  8. A simple, direct method for x-ray scatter estimation and correction in digital radiography and cone-beam CT

    SciTech Connect

    Siewerdsen, J.H.; Daly, M.J.; Bakhtiar, B.

    2006-01-15

    X-ray scatter poses a significant limitation to image quality in cone-beam CT (CBCT), resulting in contrast reduction, image artifacts, and lack of CT number accuracy. We report the performance of a simple scatter correction method in which scatter fluence is estimated directly in each projection from pixel values near the edge of the detector behind the collimator leaves. The algorithm operates on the simple assumption that signal in the collimator shadow is attributable to x-ray scatter, and the 2D scatter fluence is estimated by interpolating between pixel values measured along the top and bottom edges of the detector behind the collimator leaves. The resulting scatter fluence estimate is subtracted from each projection to yield an estimate of the primary-only images for CBCT reconstruction. Performance was investigated in phantom experiments on an experimental CBCT benchtop, and the effect on image quality was demonstrated in patient images (head, abdomen, and pelvis sites) obtained on a preclinical system for CBCT-guided radiation therapy. The algorithm provides significant reduction in scatter artifacts without compromise in contrast-to-noise ratio (CNR). For example, in a head phantom, cupping artifact was essentially eliminated, CT number accuracy was restored to within 3%, and CNR (breast-to-water) was improved by up to 50%. Similarly in a body phantom, cupping artifact was reduced by at least a factor of 2 without loss in CNR. Patient images demonstrate significantly increased uniformity, accuracy, and contrast, with an overall improvement in image quality in all sites investigated. Qualitative evaluation illustrates that soft-tissue structures that are otherwise undetectable are clearly delineated in scatter-corrected reconstructions. Since scatter is estimated directly in each projection, the algorithm is robust with respect to system geometry, patient size and heterogeneity, patient motion, etc. Operating without prior information, analytical modeling

  9. Head injury. Second edition

    SciTech Connect

    Cooper, P.R.

    1987-01-01

    This book contains 22 chapters. Some of the chapter titles are: Radiographic Evaluation; Epidemiology of Head Injury; Emergency Care and Initial Evaluation; Skull Fracture and Traumatic Cerebrospinal Fluid Fistulas; Mild Head Injury; and Injuries of the Cranial Nerves.

  10. Radial head fracture - aftercare

    MedlinePlus

    Elbow fracture - radial head - aftercare ... the radius bone, just below your elbow. A fracture is a break in your bone. The most common cause of a radial head fracture is falling with an outstretched arm.

  11. Head injury - first aid

    MedlinePlus

    ... medlineplus.gov/ency/article/000028.htm Head injury - first aid To use the sharing features on this page, ... a concussion can range from mild to severe. First Aid Learning to recognize a serious head injury and ...

  12. Increased head circumference

    MedlinePlus

    ... page: //medlineplus.gov/ency/article/003305.htm Increased head circumference To use the sharing features on this page, please enable JavaScript. Increased head circumference is when the measured distance around the ...

  13. Head and Neck Cancer

    MedlinePlus

    Head and neck cancer includes cancers of the mouth, nose, sinuses, salivary glands, throat, and lymph nodes in the ... increases your risk. In fact, 85 percent of head and neck cancers are linked to tobacco use, including smoking ...

  14. Head injury - first aid

    MedlinePlus

    ... is shaken, is the most common type of traumatic brain injury. Scalp wounds. Skull fractures. Head injuries may cause ... of people who suffer head injuries are children. Traumatic brain injury (TBI) accounts for over 1 in 6 injury- ...

  15. Head and Neck Cancer

    MedlinePlus

    Head and neck cancer includes cancers of the mouth, nose, sinuses, salivary glands, throat, and lymph nodes in the ... swallowing A change or hoarseness in the voice Head and neck cancers are twice as common in men. Using ...

  16. Dietary myo-inositol modulates immunity through antioxidant activity and the Nrf2 and E2F4/cyclin signalling factors in the head kidney and spleen following infection of juvenile fish with Aeromonas hydrophila.

    PubMed

    Jiang, Wei-Dan; Hu, Kai; Liu, Yang; Jiang, Jun; Wu, Pei; Zhao, Juan; Zhang, Yong-An; Zhou, Xiao-Qiu; Feng, Lin

    2016-02-01

    This study was conducted to investigate the effects of the dietary vitamin myo-inositol (MI), on the immunity and structural integrity of the head kidney and spleen following infection of fish with the major freshwater pathogen bacterial Aeromonas hydrophila. The results demonstrated for the first time that MI deficiency depressed the lysozyme and acid phosphatase (ACP) activities and the complement 3 (C3) and C4 contents in the head kidney and spleen compared with the optimal MI levels, indicating that MI deficiency decreased the immunity of these important fish immune organs. The depression in immunity due to MI deficiency was partially related to oxidative damage [indicated by increases in the malondialdehyde (MDA) and protein carbonyl (PC) contents] that was in turn partially due to the decreased glutathione (GSH) content and the disturbances in antioxidant enzyme activities [total superoxide dismutase (T-SOD), CuZnSOD, MnSOD, catalase (CAT), glutathione peroxidase (GPx) and glutathione reductase (GR)]. MI deficiency inhibited the antioxidant-related gene transcription [CuZnSOD, MnSOD, CAT, GPx1a, GR and NF-E2-related factor 2 (Nrf2)] in the head kidney and spleen following infection of the fish with A. hydrophila. The oxidative damage due to MI deficiency also resulted in the inhibition of proliferation-associated signalling (cyclin D1, cyclin A, cyclin E and E2F4). Thus, MI deficiency partially inhibited damage repair. Excessive MI exhibited negative effects that were similar to MI deficiency, whereas the optimal MI content reversed those indicators. These observations indicated that an MI deficiency or excess could cause depression of the immune system that might be partially related to oxidative damage, antioxidant disturbances, and the inhibition of the proliferation-associated signalling in the head kidney and spleen following infection of fish with A. hydrophila. Finally, the optimal MI levels were 660.7 (based on ACP) and 736.8 mg kg(-1) diet (based

  17. Head Start Facilities Manual.

    ERIC Educational Resources Information Center

    Research Assessment Management, Inc., Silver Spring, MD.

    A quality Head Start facility should provide a physical environment responsive both to the needs of the children and families served and to the needs of staff, volunteers, and community agencies that share space with Head Start. This manual is a tool for Head Start grantees and delegate agencies for assessing existing facilities, making…

  18. The Head Start Debates

    ERIC Educational Resources Information Center

    Zigler, Edward, Ed.; Styfco, Sally J., Ed.

    2004-01-01

    The future of Head Start depends on how well people learn from and apply the lessons from its past. That's why everyone involved in early education needs this timely, forward-thinking book from the leader of Head Start. The first book to capture the Head Start debates in all their complexity and diversity, this landmark volume brings together the…

  19. Pediatric head trauma

    PubMed Central

    Alexiou, George A; Sfakianos, George; Prodromou, Neofytos

    2011-01-01

    Head injury in children accounts for a large number of emergency department visits and hospital admissions. Falls are the most common type of injury, followed by motor-vehicle-related accidents. In the present study, we discuss the evaluation, neuroimaging and management of children with head trauma. Furthermore, we present the specific characteristics of each type of pediatric head injury. PMID:21887034

  20. TaLHY, a 1R-MYB Transcription Factor, Plays an Important Role in Disease Resistance against Stripe Rust Fungus and Ear Heading in Wheat

    PubMed Central

    Zhang, Zijin; Chen, Jieming; Su, Yongying; Liu, Hanmei; Chen, Yanger; Luo, Peigao; Du, Xiaogang; Wang, Dan; Zhang, Huaiyu

    2015-01-01

    LHY (late elongated hypocotyl) is an important gene that regulates and controls biological rhythms in plants. Additionally, LHY is highly expressed in the SSH (suppression subtractive hybridization) cDNA library-induced stripe rust pathogen (CYR32) in our previous research. To identify the function of the LHY gene in disease resistance against stripe rust, we used RACE-PCR technology to clone TaLHY in the wheat variety Chuannong19. The cDNA of TaLHY is 3085 bp long with an open reading frame of 1947 bp. TaLHY is speculated to encode a 70.3 kDa protein of 648 amino acids , which has one typical plant MYB-DNA binding domain; additionally, phylogenetic tree shows that TaLHY has the highest homology with LHY of Brachypodium distachyon(BdLHY-like). Quantitative fluorescence PCR indicates that TaLHY has higher expression in the leaf, ear and stem of wheat but lower expression in the root. Infestation of CYR32 can result in up-regulated expression of TaLHY, peaking at 72 h. Using VIGS (virus-induced gene silencing) technology to disease-resistant wheat in the fourth leaf stage, plants with silenced TaLHY cannot complete their heading stage. Through the compatible interaction with the stripe rust physiological race CYR32, Chuannong 19 loses its immune capability toward the stripe rust pathogen, indicating that TaLHY may regulate and participate in the heading of wheat, as well as the defense responses against stripe rust infection. PMID:26010918

  1. Light scattering by randomly oriented spheroidal particles

    NASA Technical Reports Server (NTRS)

    Asano, S.; Sato, M.

    1980-01-01

    A study of the light scattering properties of randomly oriented, identical spheroidal particles is presented. A computation method was developed to integrate the Asano and Yamomoto solution (1975) for scattering from a homogeneous spheroid over all particle orientations; the extinction and scattering cross-sections, the asymmetry factor, and scattering matrix elements are calculated for randomly oriented prolate and oblate spheroids and compared with the calculations for spheres and laboratory measurements. The angular scattering behavior of spheroids is found to be different from that of the spheres for side scattering to backscattering directions, and prolate and oblate spheroids of the same shape parameter have similar angular scattering patterns.

  2. Monte Carlo study of the effects of system geometry and antiscatter grids on cone-beam CT scatter distributions

    PubMed Central

    Sisniega, A.; Zbijewski, W.; Badal, A.; Kyprianou, I. S.; Stayman, J. W.; Vaquero, J. J.; Siewerdsen, J. H.

    2013-01-01

    Purpose: The proliferation of cone-beam CT (CBCT) has created interest in performance optimization, with x-ray scatter identified among the main limitations to image quality. CBCT often contends with elevated scatter, but the wide variety of imaging geometry in different CBCT configurations suggests that not all configurations are affected to the same extent. Graphics processing unit (GPU) accelerated Monte Carlo (MC) simulations are employed over a range of imaging geometries to elucidate the factors governing scatter characteristics, efficacy of antiscatter grids, guide system design, and augment development of scatter correction. Methods: A MC x-ray simulator implemented on GPU was accelerated by inclusion of variance reduction techniques (interaction splitting, forced scattering, and forced detection) and extended to include x-ray spectra and analytical models of antiscatter grids and flat-panel detectors. The simulator was applied to small animal (SA), musculoskeletal (MSK) extremity, otolaryngology (Head), breast, interventional C-arm, and on-board (kilovoltage) linear accelerator (Linac) imaging, with an axis-to-detector distance (ADD) of 5, 12, 22, 32, 60, and 50 cm, respectively. Each configuration was modeled with and without an antiscatter grid and with (i) an elliptical cylinder varying 70–280 mm in major axis; and (ii) digital murine and anthropomorphic models. The effects of scatter were evaluated in terms of the angular distribution of scatter incident upon the detector, scatter-to-primary ratio (SPR), artifact magnitude, contrast, contrast-to-noise ratio (CNR), and visual assessment. Results: Variance reduction yielded improvements in MC simulation efficiency ranging from ∼17-fold (for SA CBCT) to ∼35-fold (for Head and C-arm), with the most significant acceleration due to interaction splitting (∼6 to ∼10-fold increase in efficiency). The benefit of a more extended geometry was evident by virtue of a larger air gap—e.g., for a 16 cm

  3. Identification of genetic loci underlying the phenotypic constructs of autism spectrum disorders Running head: Genetic loci for latent factors in ASD

    PubMed Central

    Liu, Xiao-Qing; Georgiades, Stelios; Duku, Eric; Thompson, Ann; Devlin, Bernie; Cook, Edwin H.; Wijsman, Ellen M.; Paterson, Andrew D.; Szatmari, Peter

    2012-01-01

    Objective To investigate the underlying phenotypic constructs in autism spectrum disorders (ASD) and to identify genetic loci that are linked to these empirically derived factors. Method Exploratory factor analysis was applied to two datasets with 28 selected Autism Diagnostic Interview-Revised (ADI-R) algorithm items. The first dataset was from the Autism Genome Project (AGP) phase I (1,236 ASD subjects from 618 families); the second was from the AGP phase II (804 unrelated ASD subjects). Variables derived from the factor analysis were then used as quantitative traits in genome-wide variance components linkage analyses. Results Six factors, joint attention, social interaction and communication, non-verbal communication, repetitive sensory-motor behaviour, peer interaction, and compulsion/restricted interests, were retained for both datasets. There was good agreement between the factor loading patterns from the two datasets. All factors showed familial aggregation. Suggestive evidence for linkage was obtained for the joint attention factor on 11q23. Genome-wide significant evidence for linkage was obtained for the repetitive sensory-motor behaviour factor on 19q13.3. Conclusions This study demonstrates that the underlying phenotypic constructs based on the ADI-R algorithm items are replicable in independent datasets; and the empirically derived factors are suitable and informative in genetic studies of ASD. PMID:21703496

  4. The impact of concurrent granulocyte macrophage-colony stimulating factor on radiation-induced mucositis in head and neck cancer patients: A double-blind placebo-controlled prospective Phase III study by Radiation Therapy Oncology Group 9901

    SciTech Connect

    Ryu, Janice K. . E-mail: janice.ryu@ucdmc.ucdavis.edu; Swann, Suzanne; LeVeque, Francis; Johnson, Darlene J.; Chen, Allan; Fortin, Andre; Kim, Harold; Ang, Kian K.

    2007-03-01

    Purpose: Based on early clinical evidence of potential mucosal protection by granulocyte-macrophage colony stimulating factor (GM-CSF), the Radiation Therapy Oncology Group conducted a double-blind, placebo-controlled, randomized study to test the efficacy and safety of GM-CSF in reducing the severity and duration of mucosal injury and pain (mucositis) associated with curative radiotherapy (RT) in head-and-neck cancer patients. Methods and Materials: Eligible patients included those with head-and-neck cancer with radiation ports encompassing >50% of oral cavity and/or oropharynx. Standard RT ports were used to cover the primary tumor and regional lymphatics at risk in standard fractionation to 60-70 Gy. Concurrent cisplatin chemotherapy was allowed. Patients were randomized to receive subcutaneous injection of GM-CSF 250 {mu}g/m{sup 2} or placebo 3 times a week. Mucosal reaction was assessed during the course of RT using the National Cancer Institute Common Toxicity Criteria and the protocol-specific scoring system. Results: Between October 2000 and September 2002, 130 patients from 36 institutions were accrued. Nine patients (7%) were excluded from the analysis, 3 as a result of drug unavailability. More than 80% of the patients participated in the quality-of-life endpoint of this study. The GM-CSF did not cause any increase in toxicity compared with placebo. There was no statistically significant difference in the average mean mucositis score in the GM-CSF and placebo arms by a t test (p = 0.4006). Conclusion: This placebo-controlled, randomized study demonstrated no significant effect of GM-CSF given concurrently compared with placebo in reducing the severity or duration of RT-induced mucositis in patients undergoing definitive RT for head-and-neck cancer.

  5. A Multilevel Model of Child- and Classroom-Level Psychosocial Factors that Support Language and Literacy Resilience of Children in Head Start

    ERIC Educational Resources Information Center

    Maier, Michelle F.; Vitiello, Virginia E.; Greenfield, Daryl B.

    2012-01-01

    Early exposure to the multiple risk factors associated with poverty is related to an elevated risk for academic difficulty. Therefore, it is important to promote academic resilience as early as possible and to identify factors that support resilience. Given the positive relation between early language skills and later academic outcomes, examining…

  6. Self-Regulation and Self-Worth of Black Children Reared in Economically Stressed, Rural, Single Mother-Headed Families: The Contribution of Risk and Protective Factors.

    ERIC Educational Resources Information Center

    Murry, Velma McBride; Brody, Gene H.

    1999-01-01

    Examines risk and protective factors to identify processes in rural, single-parent families that are linked with positive child outcomes. Protective domains promoted greater child self-regulation; parenting protective factors promoted greater self-regulation. Maternal risk had the greatest negative effect on child self-worth. Results also reveal…

  7. Natural convection around the human head.

    PubMed

    Clark, R P; Toy, N

    1975-01-01

    1. Factors determining the convective flow patterns around the human head in 'still' conditions are discussed in relation to body posture. 2. The flow patterns have been visualized using a schlieren optical system which reveals that the head has a thicker 'insulating' layer of convecting air in the erect posture than in the supine position. 3. Local convective and radiative heat transfer measurements from the head have been using surface calorimeters. These results are seen to be closely related to the thickness of the convective boundary layer flows. 4. The total convective and radiative heat loss from the head of a subject in the erect and supine position has been evaluated from the local measurements. For the head of the supine subject the heat loss was found to be 30% more than when the subject was standing. PMID:1142118

  8. Perfusion Estimated With Rapid Dynamic Contrast-Enhanced Magnetic Resonance Imaging Correlates Inversely With Vascular Endothelial Growth Factor Expression and Pimonidazole Staining in Head-and-Neck Cancer: A Pilot Study

    SciTech Connect

    Donaldson, Stephanie B.; Betts, Guy; Bonington, Suzanne C.; Homer, Jarrod J.; Slevin, Nick J.; Kershaw, Lucy E.; Valentine, Helen; West, Catharine M.L.; Buckley, David L.

    2011-11-15

    Purpose: To analyze, in a pilot study, rapidly acquired dynamic contrast-enhanced (DCE)-MRI data with a general two-compartment exchange tracer kinetic model and correlate parameters obtained with measurements of hypoxia and vascular endothelial growth factor (VEGF) expression in patients with squamous cell carcinoma of the head and neck. Methods and Materials: Eight patients were scanned before surgery. The DCE-MRI data were acquired with 1.5-s temporal resolution and analyzed using the two-compartment exchange tracer kinetic model to obtain estimates of parameters including perfusion and permeability surface area. Twelve to 16 h before surgery, patients received an intravenous injection of pimonidazole. Samples taken during surgery were used to determine the level of pimonidazole staining using immunohistochemistry and VEGF expression using quantitative real-time polymerase chain reaction. Correlations between the biological and imaging data were examined. Results: Of the seven tumors fully analyzed, those that were poorly perfused tended to have high levels of pimonidazole staining (r = -0.79, p = 0.03) and VEGF expression (r = -0.82, p = 0.02). Tumors with low permeability surface area also tended to have high levels of hypoxia (r = -0.75, p = 0.05). Hypoxic tumors also expressed higher levels of VEGF (r = 0.82, p = 0.02). Conclusions: Estimates of perfusion obtained with rapid DCE-MRI data in patients with head-and-neck cancer correlate inversely with pimonidazole staining and VEGF expression.

  9. Head CT scan in Iranian minor head injury patients: evaluating current decision rules.

    PubMed

    Sadegh, Robab; Karimialavijeh, Ehsan; Shirani, Farzaneh; Payandemehr, Pooya; Bahramimotlagh, Hooman; Ramezani, Mahtab

    2016-02-01

    The objective of this study is to select one of the seven available clinical decision rules for minor head injury, for managing Iranian patients. This was a prospective cohort study evaluating medium- or high-risk minor head injury patients presenting to the Emergency Department. Patients with minor head trauma who were eligible for brain imaging based on seven available clinical decision rules (National Institute for Health and Clinical Excellence (NICE), National Emergency X-Radiography Utilization Study (NEXUS)-II, Neurotraumatology Committee of the World Federation of Neurosurgical Societies (NCWFNS), New Orleans, American College of Emergency Physicians (ACEP) Guideline, Scandinavian, and Canadian computed tomography (CT) head rule) were selected. Subjects were underwent a non-contrast axial spiral head CT scan. The outcome was defined as abnormal and normal head CT scan. Univariate analysis and stepwise linear regression were applied to show the best combination of risk factors for detecting CT scan abnormalities. Five hundred patients with minor head trauma were underwent brain CT scan. The following criteria were derived by stepwise linear regression: Glasgow Coma Scale (GCS) less than 15, confusion, signs of basal skull fracture, drug history of warfarin, vomiting more than once, loss of consciousness, focal neurologic deficit, and age over 65 years. This model has 86.15 % (75.33-93.45 %) sensitivity and 46.44 % (46.67-51.25 %) specificity in detecting minor head injury patients with CT scan abnormalities (95 % confidence interval). Of seven decision rules, only the Canadian CT Head Rule possesses seven of the eight high-risk factors associated with abnormal head CT results which were identified by this study. This study underlines the Canadian CT Head Rule's utility in Iranian minor head injury patients. Our study encourages researchers to evaluate available guidelines in different communities. PMID:26407978

  10. Abusive head trauma: past, present, and future.

    PubMed

    Narang, Sandeep; Clarke, Jennifer

    2014-12-01

    Abusive head trauma has a robust and interesting scientific history. Recently, the American Academy of Pediatrics has endorsed a change in terminology to a term that is more general in describing the vast array of abusive mechanisms that can result in pediatric head injury. Simply defined, abusive head trauma is "child physical abuse that results in injury to the head or brain." Abusive head trauma is a relatively common cause of childhood neurotrauma, with an estimated incidence of 16 to 33 cases per 100,000 children per year in the first 2 years of life. Clinical findings are variable; AHT should be considered in all children with neurologic signs and symptoms, especially if no or only mild trauma is described. Subdural and retinal hemorrhages are the most common findings. The current best evidence-based literature has identified some features--apnea and severe retinal hemorrhages--that reliably discriminate abusive from accidental injury. Longitudinal studies of outcomes in abusive head trauma patients demonstrate that approximately one-third of the children are severely disabled, one third of them are moderately disabled, and one third have no or only mild symptoms. Abusive head trauma cases are complex cases that require a rigorous, multidisciplinary team approach. The clinician can establish this diagnosis with confidence if he/she maintains a high index of suspicion for the diagnosis, has knowledge of the signs, symptoms, and risk factors of abusive head trauma, and reasonably excludes other etiologies on the differential diagnosis. PMID:25316728

  11. Indoor air pollution by emissions of fossil fuel single stoves: possibly a hitherto underrated risk factor in the development of carcinomas in the head and neck.

    PubMed

    Dietz, A; Senneweld, E; Maier, H

    1995-02-01

    We have carried out three case-control studies on the relative risk of head and neck cancer in association with indoor air pollution. The studies performed at the Department of Otorhinolaryngology of the University of Heidelberg comprised 369 male patients with squamous cell carcinoma of the oral cavity, pharynx, and larynx and 1476 healthy control subjects matched for sex, age, and residential area. The OR of laryngeal cancer related to daily exposure to fossil fuels due to stove-heating with oil, coal, gas, and wood for longer than 40 years was 2.5 (CI = 1.51 to 4.05). After adjustment for tobacco and alcohol, the OR declined slightly to 2.0 (CI = 1.10 to 3.46) but still was significant. Elevated ORs were also found for daily presence in a kitchen with an oil, coal, or wood oven for longer than 40 years (OR = 1.7, CI = 1.01 to 2.71; after tobacco and alcohol adjustment, OR = 1.4, CI = 0.76 to 2.41). The OR of pharyngeal cancer related to daily exposure to fossil fuels due to stove-heating with oil, coal, gas, and wood for longer than 40 years was 3.6 (CI = 2.04 to 6.41). After adjustment for tobacco and alcohol the OR declined slightly to 3.3 (CI = 1.43 to 7.55) but still was significant. Elevated ORs were also found for daily presence in a kitchen with an oil, coal, or wood oven for longer than 40 years (OR = 1.6, CI = 0.89 to 2.77; after tobacco and alcohol adjustment, OR = 2.5, CI = 1.03 to 6.30).(ABSTRACT TRUNCATED AT 250 WORDS) PMID:7838555

  12. [Indoor air pollution by emissions from individual fossil fuel stoves. Possibly a so-far underestimated risk factor in development of cancers of the head and neck area].

    PubMed

    Dietz, A; Sennewald, E; Maier, H

    1994-01-01

    We have carried out three case-control studies on the relative risk of head and neck cancer in association with indoor air pollution. The studies performed at the Department of Otorhinolaryngology of the University of Heidelberg comprised 369 male patients with squamous cell carcinomas of the oral cavity, pharynx and larynx; one thousand, four hundred and seventy-six healthy subjects were used as controls and were matched for sex, age and residential area. The relative risk (RR) of laryngeal cancer related to daily exposure to fossil fuels due to stove heating with oil, coal, gas and wood in a period longer than 40 years was 2.5 [confidence interval (CI): 1.51-4.05]. After adjustment for tobacco and alcohol the RR declined slightly to 2.0 [CI: 1.10-3.46] but was still significant. Increased risks were also found for daily exposure in a kitchen containing air oil, coal or wood oven for a period longer than 40 years (RR = 1.7; CI: 1.01-2.71). In this latter group the RR because 1.4 after adjustments for use of tobacco and alcohol [CI: 0.76-2.41]). The RR of pharyngeal cancer related to daily exposure to fossil fuels due to stove heating with oil, coal, gas and wood in a period longer than 40 years was 3.6 [CI: 2.04-6.41]. After adjustments were made for tobacco and alcohol, the RR declined slightly to 3.3 [CI: 1.43-7.55] but was still significant. Elevated risks were also found for daily presence in a kitchen with oil, coal or wood ovens for a period longer than 40 years (RR = 1.6 [CI: 0.89-2.77].(ABSTRACT TRUNCATED AT 250 WORDS) PMID:8150673

  13. Small angle neutron scattering

    NASA Astrophysics Data System (ADS)

    Cousin, Fabrice

    2015-10-01

    Small Angle Neutron Scattering (SANS) is a technique that enables to probe the 3-D structure of materials on a typical size range lying from ˜ 1 nm up to ˜ a few 100 nm, the obtained information being statistically averaged on a sample whose volume is ˜ 1 cm3. This very rich technique enables to make a full structural characterization of a given object of nanometric dimensions (radius of gyration, shape, volume or mass, fractal dimension, specific area…) through the determination of the form factor as well as the determination of the way objects are organized within in a continuous media, and therefore to describe interactions between them, through the determination of the structure factor. The specific properties of neutrons (possibility of tuning the scattering intensity by using the isotopic substitution, sensitivity to magnetism, negligible absorption, low energy of the incident neutrons) make it particularly interesting in the fields of soft matter, biophysics, magnetic materials and metallurgy. In particular, the contrast variation methods allow to extract some informations that cannot be obtained by any other experimental techniques. This course is divided in two parts. The first one is devoted to the description of the principle of SANS: basics (formalism, coherent scattering/incoherent scattering, notion of elementary scatterer), form factor analysis (I(q→0), Guinier regime, intermediate regime, Porod regime, polydisperse system), structure factor analysis (2nd Virial coefficient, integral equations, characterization of aggregates), and contrast variation methods (how to create contrast in an homogeneous system, matching in ternary systems, extrapolation to zero concentration, Zero Averaged Contrast). It is illustrated by some representative examples. The second one describes the experimental aspects of SANS to guide user in its future experiments: description of SANS spectrometer, resolution of the spectrometer, optimization of spectrometer

  14. Sea-urchin-like Au nanocluster with surface-enhanced raman scattering in detecting epidermal growth factor receptor (EGFR) mutation status of malignant pleural effusion.

    PubMed

    Wang, Lei; Guo, Ting; Lu, Qiang; Yan, Xiaolong; Zhong, Daixing; Zhang, Zhipei; Ni, Yunfeng; Han, Yong; Cui, Daxiang; Li, Xiaofei; Huang, Lijun

    2015-01-14

    Somatic mutations in the epidermal growth factor receptor (EGFR) gene are common in patients with lung adenocarcinomas and are associated with sensitivity to the small-molecule tyrosine kinase inhibitors (TKIs). For 10%-50% of the patients who experienced malignant pleural effusion (MPE), pathological diagnosis might rely exclusively on finding lung cancer cells in the MPE. Current methods based on polymerase chain reaction were utilized to test EGFR mutation status of MPE samples, but the accuracy of the test data was very low, resulting in many patients losing the chance of TKIs treatment. Herein, we synthesized the sea-urchin-like Au nanocluster (AuNC) with an average diameter of 92.4 nm, composed of 15-nm nanopricks. By introducing abundant sharp nanopricks, the enhancement factor of AuNC reached at 1.97 × 10(7). After capped with crystal violet (CV), polyethylene glycol, and EGFR mutation specific antibody, the AuNC-EGFR had excellent surface-enhanced Raman scattering (SERS) activity and EGFR mutation targeted recognition capability in lung cancer cells. Characteristic SERS signal at 1617 cm(-1) of CV was linear correlation with the number of H1650 cells, demonstrating the minimum detection limit as 25 cells in a 1-mL suspension. The gold mass in single H1650 cells exposed to AuNC-E746_750 for 2 h ranged from 208.6 pg to 231.4 pg, which approximately corresponded to 56-62 AuNCs per cell. Furthermore, SERS was preclinically utilized to test EGFR mutation status in MPE samples from 35 patients with lung adenocarcinoma. Principal component analysis (PCA) and the support vector machine (SVM) algorithm were constructed for EGFR mutation diagnostic analysis, yielding an overall accuracy of 90.7%. SERS measurement based on sea-urchin-like AuNC was an efficient method for EGFR mutation detection in MPE, and it might show great potential in applications such as predicting gene typing of clinical lung cancer in the near future. PMID:25495142

  15. Treatment of head lice.

    PubMed

    Diamantis, Stephanie A; Morrell, Dean S; Burkhart, Craig N

    2009-01-01

    Pediculosis capitis, or head lice, is a common infestation among children worldwide. Multiple therapies exist for the treatment of this condition, including topical pediculicides and oral medications. When used in combination with environmental decontamination, these drugs can be very effective in eradicating head lice infestation without significant adverse events. The present study discusses the use of available over-the-counter and prescription treatments, including pyrethroids and permethrin, lindane, malathion, ivermectin, and trimethoprim-sulfamethoxazole, in the treatment of head lice. PMID:19580574

  16. Head Lag in Infancy: What Is It Telling Us?

    PubMed Central

    Reynolds, Lauren C.; Seefeldt, Kristin; Hilton, Claudia L.; Rogers, Cynthia L.; Inder, Terrie E.

    2016-01-01

    OBJECTIVE. To investigate changes in head lag across postmenstrual age and define associations between head lag and (1) perinatal exposures and (2) neurodevelopment. METHOD. Sixty-four infants born ≤30 wk gestation had head lag assessed before and at term-equivalent age. Neurobehavior was assessed at term age. At 2 yr, neurodevelopmental testing was conducted. RESULTS. Head lag decreased with advancing postmenstrual age, but 58% (n = 37) of infants continued to demonstrate head lag at term. Head lag was associated with longer stay in the neonatal intensive care unit (p = .009), inotrope use (p = .04), sepsis (p = .02), longer endotracheal intubation (p = .01), and cerebral injury (p = .006). Head lag was related to alterations in early neurobehavior (p < .03), but no associations with neurodevelopment were found at 2 yr. CONCLUSION. Head lag was related to medical factors and early neurobehavior, but it may not be a good predictor of outcome when used in isolation. PMID:26709421

  17. Deposition head for laser

    DOEpatents

    Lewis, Gary K.; Less, Richard M.

    1999-01-01

    A deposition head for use as a part of apparatus for forming articles from materials in particulate form in which the materials are melted by a laser beam and deposited at points along a tool path to form an article of the desired shape and dimensions. The deposition head delivers the laser beam and powder to a deposition zone, which is formed at the tip of the deposition head. A controller comprised of a digital computer directs movement of the deposition zone along the tool path and provides control signals to adjust apparatus functions, such as the speed at which the deposition head moves along the tool path.

  18. Bottom head assembly

    DOEpatents

    Fife, A.B.

    1998-09-01

    A bottom head dome assembly is described which includes, in one embodiment, a bottom head dome and a liner configured to be positioned proximate the bottom head dome. The bottom head dome has a plurality of openings extending there through. The liner also has a plurality of openings extending there through, and each liner opening aligns with a respective bottom head dome opening. A seal is formed, such as by welding, between the liner and the bottom head dome to resist entry of water between the liner and the bottom head dome at the edge of the liner. In the one embodiment, a plurality of stub tubes are secured to the liner. Each stub tube has a bore extending there through, and each stub tube bore is coaxially aligned with a respective liner opening. A seat portion is formed by each liner opening for receiving a portion of the respective stub tube. The assembly also includes a plurality of support shims positioned between the bottom head dome and the liner for supporting the liner. In one embodiment, each support shim includes a support stub having a bore there through, and each support stub bore aligns with a respective bottom head dome opening. 2 figs.

  19. Bottom head assembly

    DOEpatents

    Fife, Alex Blair

    1998-01-01

    A bottom head dome assembly which includes, in one embodiment, a bottom head dome and a liner configured to be positioned proximate the bottom head dome is described. The bottom head dome has a plurality of openings extending therethrough. The liner also has a plurality of openings extending therethrough, and each liner opening aligns with a respective bottom head dome opening. A seal is formed, such as by welding, between the liner and the bottom head dome to resist entry of water between the liner and the bottom head dome at the edge of the liner. In the one embodiment, a plurality of stub tubes are secured to the liner. Each stub tube has a bore extending therethrough, and each stub tube bore is coaxially aligned with a respective liner opening. A seat portion is formed by each liner opening for receiving a portion of the respective stub tube. The assembly also includes a plurality of support shims positioned between the bottom head dome and the liner for supporting the liner. In one embodiment, each support shim includes a support stub having a bore therethrough, and each support stub bore aligns with a respective bottom head dome opening.

  20. Factors Associated with Incidence of "Inappropriate" Ambulance Transport in Rural Areas in Cases of Moderate to Severe Head Injury in Children

    ERIC Educational Resources Information Center

    Poltavski, Dmitri; Muus, Kyle

    2005-01-01

    Context: Ambulance transport of pediatric trauma patients to designated trauma centers in cases of moderate and severe injury is not always performed, which has been shown to result in poor treatment outcomes. Determination of factors involved in inappropriate patient transport, especially in rural areas, remains an important avenue of research.…

  1. Factors Associated With Incidence of "?Inappropriate"? Ambulance Transport in Rural Areas in Cases of Moderate to Severe Head Injury in Children

    ERIC Educational Resources Information Center

    Poltavski, Dmitri; Muus, Kyle

    2005-01-01

    Context: Ambulance transport of pediatric trauma patients to designated trauma centers in cases of moderate and severe injury is not always performed, which has been shown to result in poor treatment outcomes. Determination of factors involved in inappropriate patient transport, especially in rural areas, remains an important avenue of research.…

  2. A New Polyethylene Scattering Law Determined Using Inelastic Neutron Scattering

    SciTech Connect

    Lavelle, Christopher M; Liu, C; Stone, Matthew B

    2013-01-01

    Monte Carlo neutron transport codes such as MCNP rely on accurate data for nuclear physics cross-sections to produce accurate results. At low energy, this takes the form of scattering laws based on the dynamic structure factor, S (Q, E). High density polyethylene (HDPE) is frequently employed as a neutron moderator at both high and low temperatures, however the only cross-sections available are for T =300 K, and the evaluation has not been updated in quite some time. In this paper we describe inelastic neutron scattering measurements on HDPE at 5 and 300 K which are used to improve the scattering law for HDPE. We describe the experimental methods, review some of the past HDPE scattering laws, and compare computations using these models to the measured S (Q, E). The total cross-section is compared to available data, and the treatment of the carbon secondary scatterer as a free gas is assessed. We also discuss the use of the measurement itself as a scattering law via the 1 phonon approximation. We show that a scattering law computed using a more detailed model for the Generalized Density of States (GDOS) compares more favorably to this experiment, suggesting that inelastic neutron scattering can play an important role in both the development and validation of new scattering laws for Monte Carlo work.

  3. Animal Models of Head Trauma

    PubMed Central

    Cernak, Ibolja

    2005-01-01

    Summary: Animal models of traumatic brain injury (TBI) are used to elucidate primary and secondary sequelae underlying human head injury in an effort to identify potential neuroprotective therapies for developing and adult brains. The choice of experimental model depends upon both the research goal and underlying objectives. The intrinsic ability to study injury-induced changes in behavior, physiology, metabolism, the blood/tissue interface, the blood brain barrier, and/or inflammatory- and immune-mediated responses, makes in vivo TBI models essential for neurotrauma research. Whereas human TBI is a highly complex multifactorial disorder, animal trauma models tend to replicate only single factors involved in the pathobiology of head injury using genetically well-defined inbred animals of a single sex. Although such an experimental approach is helpful to delineate key injury mechanisms, the simplicity and hence inability of animal models to reflect the complexity of clinical head injury may underlie the discrepancy between preclinical and clinical trials of neuroprotective therapeutics. Thus, a search continues for new animal models, which would more closely mimic the highly heterogeneous nature of human TBI, and address key factors in treatment optimization. PMID:16389305

  4. Head Injuries in Children

    ERIC Educational Resources Information Center

    Pennington, Nicole

    2010-01-01

    School nurses play a crucial role in injury prevention and initial treatment when injuries occur at school. The role of school nurses includes being knowledgeable about the management of head injuries, including assessment and initial treatment. The school nurse must be familiar with the outcomes of a head injury and know when further evaluation…

  5. SU-E-T-298: Small Field Total Scatter Factors Using a Commercial Scintillator Detector: Calibration Parameters Are Not Independent of Field Size

    SciTech Connect

    Jornet, N; Carrasco de Fez, P; Jordi, O; Latorre-Musoll, A; Eudaldo, T; Ruiz-Martinez, A; Ribas Morales, M

    2014-06-01

    Purpose: To evaluate the accuracy in total scatter factor (Sc,p) determination for small fields using commercial plastic scintillator detector (PSD). The manufacturer's spectral discrimination method to subtract Cerenkov light from the signal is discussed. Methods: Sc,p for field sizes ranging from 0.5 to 10 cm were measured using PSD Exradin (Standard Imaging) connected to two channel electrometer measuring the signals in two different spectral regions to subtract the Cerenkov signal from the PSD signal. A Pinpoint ionisation chamber 31006 (PTW) and a non-shielded semiconductor detector EFD (Scanditronix) were used for comparison. Measures were performed for a 6 MV X-ray beam. The Sc,p are measured at 10 cm depth in water for a SSD=100 cm and normalized to a 10'10 cm{sup 2} field size at the isocenter. All detectors were placed with their symmetry axis parallel to the beam axis.We followed the manufacturer's recommended calibration methodology to subtract the Cerenkov contribution to the signal as well as a modified method using smaller field sizes. The Sc,p calculated by using both calibration methodologies were compared. Results: Sc,p measured with the semiconductor and the PinPoint detectors agree, within 1.5%, for field sizes between 10'10 and 1'1 cm{sup 2}. Sc,p measured with the PSD using the manufacturer's calibration methodology were systematically 4% higher than those measured with the semiconductor detector for field sizes smaller than 5'5 cm{sup 2}. By using a modified calibration methodology for smalls fields and keeping the manufacturer calibration methodology for fields larger than 5'5cm{sup 2} field Sc,p matched semiconductor results within 2% field sizes larger than 1.5 cm. Conclusion: The calibration methodology proposed by the manufacturer is not appropriate for dose measurements in small fields. The calibration parameters are not independent of the incident radiation spectrum for this PSD. This work was partially financed by grant 2012 of

  6. Effects of the environmental factors on the casein micelle structure studied by cryo transmission electron microscopy and small-angle x-ray scattering/ultrasmall-angle x-ray scattering

    NASA Astrophysics Data System (ADS)

    Marchin, Stéphane; Putaux, Jean-Luc; Pignon, Frédéric; Léonil, Joëlle

    2007-01-01

    Casein micelles are colloidal protein-calcium-transport complexes whose structure has not been unequivocally elucidated. This study used small-angle x-ray scattering (SAXS) and ultrasmall angle x-ray scattering (USAXS) as well as cryo transmission electron microscopy (cryo-TEM) to provide fine structural details on their structure. Cryo-TEM observations of native casein micelles fractionated by differential centrifugation showed that colloidal calcium phosphate appeared as nanoclusters with a diameter of about 2.5nm. They were uniformly distributed in a homogeneous tangled web of caseins and were primarily responsible for the intensity distribution in the SAXS profiles at the highest q vectors corresponding to the internal structure of the casein micelles. A specific demineralization of casein micelles by decreasing the pH from 6.7 to 5.2 resulted in a reduced granular aspect of the micelles observed by cryo-TEM and the existence of a characteristic point of inflection in SAXS profiles. This supports the hypothesis that the smaller substructures detected by SAXS are colloidal calcium phosphate nanoclusters rather than putative submicelles.

  7. American Head and Neck Society

    MedlinePlus

    American Head & Neck Society Head and Neck Cancer Research & Education American Head & Neck Society | AHNS Head and Neck Cancer Research & Education About AHNS ... and Announcements Copyright ©2016 · American Head and Neck Society · Privacy and Return Policy Managed by BSC Management, ...

  8. Trunnion-Head Stresses in THA: Are Big Heads Trouble?

    PubMed

    Lavernia, Carlos J; Iacobelli, David A; Villa, Jesus M; Jones, Kinzy; Gonzalez, Jose L; Jones, William Kinzy

    2015-06-01

    The effects of large heads on stresses at the THA trunnion-head junction and their impact on tribocorrosion/metal ion release remain controversial. A 12/14 3D-model of a stem with different head sizes was investigated. Material properties of titanium were assigned to the trunnion and cobalt-chrome/alumina to the heads. A load simulating walking single-leg stand phase was applied to the head. A total contact head-trunnion interface was assumed. The area underneath the junction underwent significant elevations in stresses as head size increased from 28- to 40-mm. Maximum principal stress doubled between 28 and 40-mm heads, regardless of head material. Stress levels had a direct correlation to head diameter. Stress increases observed using increasingly larger heads will probably contribute to head-trunnion tribocorrosion and ion release. PMID:25724112

  9. Estimating the Analytical and Surface Enhancement Factors in Surface-Enhanced Raman Scattering (SERS): A Novel Physical Chemistry and Nanotechnology Laboratory Experiment

    ERIC Educational Resources Information Center

    Pavel, Ioana E.; Alnajjar, Khadijeh S.; Monahan, Jennifer L.; Stahler, Adam; Hunter, Nora E.; Weaver, Kent M.; Baker, Joshua D.; Meyerhoefer, Allie J.; Dolson, David A.

    2012-01-01

    A novel laboratory experiment was successfully implemented for undergraduate and graduate students in physical chemistry and nanotechnology. The main goal of the experiment was to rigorously determine the surface-enhanced Raman scattering (SERS)-based sensing capabilities of colloidal silver nanoparticles (AgNPs). These were quantified by…

  10. Characterization of the murine gene of gC1qBP, a novel cell protein that binds the globular heads of C1q, vitronectin, high molecular weight kininogen and factor XII.

    PubMed

    Lim, B L; White, R A; Hummel, G S; Schwaeble, W; Lynch, N J; Peerschke, E I; Reid, K B; Ghebrehiwet, B

    1998-03-16

    gC1qBP is a novel cell protein which was found to interact with the globular heads of C1q, high mol. wt kininogen, factor XII and the heparin-binding, multimeric form of vitronectin. The protein sequence shows no homology to any protein family. This paper describes the genomic organization of mouse gC1qBP and the characterization of its 5' flanking region. The mouse gene consists of six exons separated by five introns, and its total length is approximately 6kb. Exon 1 encodes the putative signal peptide, a long stretch of 70 amino acid residues, and the first four amino acid residues found in the mature gC1qBP. Exons 2-5 encode four very hydrophilic domains, whereas exon 6 encodes a neutral domain. The amino acid sequence responsible for binding to the heparin-binding, multimeric form of vitronectin is located in exon 2. A 1kb DNA fragment upstream of the first initiation codon was sequenced, which contained four potential TATA boxes, seven CAAT boxes, six SP1 sites and various putative transcription factor-binding elements, indicating that the promoter region is in close proximity to the first exon. The mouseC1qbp gene was mapped to chromosome 11, closely linked to D11Mit4 using genomic DNAs from a (C57BL/6J x Mus spretus)F1 x Mus spretus backcross. PMID:9524273

  11. Head Circumference and Neurocognitive Outcomes.

    PubMed

    Millichap, J Gordon

    2015-07-01

    Investigators from Universities of Glasgow and Bristol, UK, determined the value of head circumference (HC) as a screening measure, the incidence of head centile shifting, and the relationship between extremes of head size and later neurodevelopmental problems. PMID:26933592

  12. Compressional head waves in attenuative formations

    SciTech Connect

    Liu, Q.H.; Chang, C.

    1994-12-31

    The attenuation of compressional head waves in a fluid-filled borehole is studied with the branch-cut integration method. The borehole fluid and solid formation are both assumed lossy with quality factors Q{sub f}({omega}) for the fluid, and Q{sub c}({omega}) and Q{sub s}({omega}) for the compressional and shear waves in the solid, respectively. The branch-cut integration method used in this work is an extension of that for a lossless medium. With this branch-cut integration method, the authors can isolate the groups of individual arrivals such as the compressional head waves and shear head waves, and study the attenuation of those particular wavefields in lossy media. This study, coupled with experimental work to be performed, may result in an effective way of measuring compressional head wave attenuation in the field.

  13. Maneuvering impact boring head

    DOEpatents

    Zollinger, W.T.; Reutzel, E.W.

    1998-08-18

    An impact boring head may comprise a main body having an internal cavity with a front end and a rear end. A striker having a head end and a tail end is slidably mounted in the internal cavity of the main body so that the striker can be reciprocated between a forward position and an aft position in response to hydraulic pressure. A compressible gas contained in the internal cavity between the head end of the striker and the front end of the internal cavity returns the striker to the aft position upon removal of the hydraulic pressure. 8 figs.

  14. Maneuvering impact boring head

    DOEpatents

    Zollinger, W. Thor; Reutzel, Edward W.

    1998-01-01

    An impact boring head may comprise a main body having an internal cavity with a front end and a rear end. A striker having a head end and a tail end is slidably mounted in the internal cavity of the main body so that the striker can be reciprocated between a forward position and an aft position in response to hydraulic pressure. A compressible gas contained in the internal cavity between the head end of the striker and the front end of the internal cavity returns the striker to the aft position upon removal of the hydraulic pressure.

  15. The compressive stiffness of human pediatric heads.

    PubMed

    Loyd, Andre Matthew; Nightingale, Roger W; Luck, Jason F; Song, Yin; Fronheiser, Lucy; Cutcliffe, Hattie; Myers, Barry S; Dale Bass, Cameron R

    2015-11-01

    Head injury is a persistent and costly problem for both children and adults. Globally, approximately 10 million people are hospitalized each year for head injuries. Knowing the structural properties of the head is important for modeling the response of the head in impact, and for providing insights into mechanisms of head injury. Hence, the goal of this study was to measure the sub-injurious structural stiffness of whole pediatric heads. 12 cadaveric pediatric (20-week-gestation to 16 years old) heads were tested in a battery of viscoelastic compression tests. The heads were compressed in both the lateral and anterior-posterior directions to 5% of gauge length at normalized deformation rates of 0.0005/s, 0.01/s, 0.1/s, and 0.3/s. Because of the non-linear nature of the response, linear regression models were used to calculate toe region (<2.5%) and elastic region (>2.5%) stiffness separately so that meaningful comparisons could be made across rate, age, and direction. The results showed that age was the dominant factor in predicting the structural stiffness of the human head. A large and statistically significant increase in the stiffness of both the toe region and the elastic region was observed with increasing age (p<0.0001), but no significant difference was seen across direction or normalized deformation rate. The stiffness of the elastic region increased from as low as 5 N/mm in the neonate to >4500 N/mm in the 16 year old. The changes in stiffness with age may be attributed to the disappearance of soft sutures and the thickening of skull bones with age. PMID:26476760

  16. Arthroplasty in Femoral Head Osteonecrosis

    PubMed Central

    Nam, Dong Cheol; Jung, Kwangyoung

    2014-01-01

    Osteonecrosis of the femoral head is a destructive joint disease requiring early hip arthroplasty. The polyethylene-metal design using a 22-mm femoral head component, introduced by Charnley in 1950, has been widely used for over half a century. Since then, different materials with the capacity to minimize friction between bearing surfaces and various cement or cementless insert fixations have been developed. Although the outcome of second and third generation designs using better bearing materials and technologies has been favorable, less favorable results are seen with total hip arthroplasty in young patients with osteonecrosis. Selection of appropriate materials for hip arthroplasty is important for any potential revisions that might become inevitable due to the limited durability of a prosthetic hip joint. Alternative hip arthroplasties, which include hemiresurfacing arthroplasty and bipolar hemiarthroplasty, have not been found to have acceptable outcomes. Metal-on-metal resurfacing has recently been suggested as a feasible option for young patients with extra physical demands; however, concerns about complications such as hypersensitivity reaction or pseudotumor formation on metal bearings have emerged. To ensure successful long-term outcomes in hip arthroplasty, factors such as insert stabilization and surfaces with less friction are essential. Understanding these aspects in arthroplasty is important to selection of proper materials and to making appropriate decisions for patients with osteonecrosis of the femoral head. PMID:27536561

  17. Selective Uptake and Imaging of Aptamer- and Antibody-Conjugated Hollow Nanospheres Targeted to Epidermal Growth Factor Receptors Overexpressed in Head and Neck Cancer

    PubMed Central

    2015-01-01

    The purpose of this study was to compare the binding affinity and selective targeting of aptamer- and antibody-coated hollow gold nanospheres (HAuNS) targeted to epidermal growth factor receptors (EGFR). EGFR-targeting aptamers were conjugated to HAuNS (apt-HAuNS) by attaching a thiol-terminated single-stranded DNA to the HAuNS and then adding the complementary RNA targeted to EGFR. Apt-HAuNS was characterized in terms of size, surface charge, absorption, and number of aptamers per particle. The in vivo pharmacokinetics, in vivo biodistribution, and micro-SPECT/CT imaging of 111In-labeled apt-HAuNS and anti-EGFR antibody (C225)-conjugated HAuNS were evaluated in nude mice bearing highly malignant human OSC-19 oral tumors. 111In-labeled PEG-HAuNS was used as a control (n = 5/group). Apt-HAuNS did not have an altered absorbance profile or size (λmax = 800 nm; diameter = 55 nm) compared to C225-HAuNS or PEG-HAuNS. The surface charge became more negative upon conjugation of the aptamer (−51.4 vs −19.0 for PEG-HAuNS and −25.0 for C225-HAuNS). The number of aptamers/particle was ∼250. In vitro cell binding and in vivo biodistribution showed selective binding of the apt-HAuNS to EGFR. μSPECT/CT imaging confirmed that there was more tumor uptake of apt-HAuNS than C225-HAuNS. Aptamer is a promising ligand for image-guided delivery of nanoparticles for treatment of tumor cells overexpressing EGFR. PMID:24754567

  18. Head and Neck Cancer

    MedlinePlus

    ... head and neck cancer. Poor oral and dental hygiene . Poor care of the mouth and teeth has ... sore throat Foul mouth odor not explained by hygiene Hoarseness or change in voice Nasal obstruction or ...

  19. Head Lice: Treatment

    MedlinePlus

    ... it may be necessary to use a second bottle. Pay special attention to instructions on the label ... or printed on the label. Nit (head lice egg) combs, often found in lice medicine packages, should ...

  20. Overview of Head Injuries

    MedlinePlus

    ... to Baby Health Highlights: Sept. 13, 2016 Smokers' Perceptions May Play Role in Addiction Sugar Companies Shifted ... amount of oxygen given and the rate and depth of breaths given by the ventilator. The head ...

  1. Abnormal Head Position

    MedlinePlus

    ... syndrome, Brown’s syndrome, orbital wall fractures, and restricted eye movement associated with thyroid eye disease. 2) Nystagmus: Some patients with nystagmus (jerky eye movements) will acquire a head turn or tilt if ...

  2. Head CT scan

    MedlinePlus

    Brain CT; Cranial CT; CT scan - skull; CT scan - head; CT scan - orbits; CT scan - sinuses; Computed tomography - cranial ... or other growth (mass) Cerebral atrophy (loss of brain tissue) ... with the hearing nerve Stroke or transient ischemic attack (TIA)

  3. Ultrasound: Head (For Parents)

    MedlinePlus

    ... the head and images are recorded on a computer. The black-and-white images show the internal ... the images can be seen clearly on the computer screen. A technician (sonographer) trained in ultrasound imaging ...

  4. Head tilt during driving.

    PubMed

    Zikovitz, D C; Harris, L R

    1999-05-01

    In order to distinguish between the use of visual and gravito-inertial force reference frames, the head tilt of drivers and passengers were measured as they went around corners at various speeds. The visual curvature of the corners were thus dissociated from the magnitude of the centripetal forces (0.30-0.77 g). Drivers' head tilts were highly correlated with the visually-available estimate of the curvature of the road (r2=0.86) but not with the centripetal force (r2<0.1). Passengers' head tilts were inversely correlated with the lateral forces (r2=0.3-0.7) and seem to reflect a passive sway. The strong correlation of the tilt of drivers' heads with a visual aspect of the road ahead, supports the use of a predominantly visual reference frame for the driving task. PMID:10722313

  5. TCGA head Neck

    Cancer.gov

    Investigators with The Cancer Genome Atlas (TCGA) Research Network have discovered genomic differences – with potentially important clinical implications – in head and neck cancers caused by infection with the human papillomavirus (HPV).

  6. Head Injuries in Soccer.

    ERIC Educational Resources Information Center

    Fields, Karl B.

    1989-01-01

    This article reviews the medical literature on head injuries in soccer and concludes that protective headgear to reduce these injuries may not be as effective as rule changes and other measures, such as padding goal posts. (IAH)

  7. Treating Head Lice

    MedlinePlus

    ... and Prevention. Head lice are most common among preschool children attending child care, elementary school children, and ... Emergency Preparedness International Programs News & Events Training & Continuing Education Inspections & Compliance Federal, State & Local Officials Consumers Health ...

  8. (Gamma scattering in condensed matter with high intensity Moessbauer radiation)

    SciTech Connect

    Not Available

    1992-01-01

    This report discusses: quasielastic scattering studies on glycerol; gamma-ray scattering from alkali halides; lattice dynamics in metals; Moessbauer neutron scattering, x-ray diffraction, and macroscopic studies of high {Tc} superconductors containing tungsten; NiAl scattering studies; and atomic interference factors and nuclear Casimir effect.

  9. Recurrent Catastrophic Ceramic Femoral Head Failure in Total Hip Arthroplasty

    PubMed Central

    Tai, S. M. M.; Parker, L.; de Roeck, N. J.; Skinner, J. A.

    2014-01-01

    Fracture of a modern ceramic head component in total hip replacement is an uncommon but catastrophic complication. Hence, the occurrence of a second ceramic head fracture in the same hip replacement of an individual represents a perishingly rare event. We present the case as a means of highlighting potential risk factors for ceramic head fracture and suggest possible management strategies in such cases. PMID:24991441

  10. “Time is brain” the Gifford factor - or: Why do some civilian gunshot wounds to the head do unexpectedly well? A case series with outcomes analysis and a management guide

    PubMed Central

    Lin, David J.; Lam, Fred C.; Siracuse, Jeffrey J.; Thomas, Ajith; Kasper, Ekkehard M.

    2012-01-01

    Background: Review of intracranial gunshot wounds (GSWs) undergoing emergent neurosurgical intervention despite a very low Glasgow Coma Scale (GCS) score on admission in order to identify predictors of good outcome, with correlates to recent literature. Methods: A retrospective review of select cases of GSWs presenting to our trauma center over the past 5 years with poor GCS requiring emergent neurosurgical intervention and a minimum of 1-year follow-up. Results: Out of a total of 17 patients who went to the operating room (OR) for GSW to the head during this period, 4 cases with a GCS < 5 on admission were identified. All cases required a hemicraniectomy to alleviate cerebral swelling. Two cases presented with a unilaterally blown pupil due to raised intracranial pressure. The remaining 2 cases had equal and reactive pupils. One patient with a GCS of 3 and a significant bilateral pattern of parenchymal bullet injury was initially assessed in moribund status but rallied and received a delayed hemicraniectomy on day 7. Three out of 4 patients are functionally independent at 1-year follow-up. The fourth patient who received a delayed decompression remains wheelchair dependent. Conclusion: Victims of GSWs can have good outcomes despite having a very poor admission GCS score and papillary abnormalities. Factors predicting good outcomes include the following: time from injury to surgical intervention of < 1 h; injury to noneloquent brain; and absence of injury to midbrain, brainstem, and major vessels. PMID:23061014

  11. Methods and apparatus for transparent display using scattering nanoparticles

    DOEpatents

    Hsu, Chia Wei; Qiu, Wenjun; Zhen, Bo; Shapira, Ofer; Soljacic, Marin

    2016-05-10

    Transparent displays enable many useful applications, including heads-up displays for cars and aircraft as well as displays on eyeglasses and glass windows. Unfortunately, transparent displays made of organic light-emitting diodes are typically expensive and opaque. Heads-up displays often require fixed light sources and have limited viewing angles. And transparent displays that use frequency conversion are typically energy inefficient. Conversely, the present transparent displays operate by scattering visible light from resonant nanoparticles with narrowband scattering cross sections and small absorption cross sections. More specifically, projecting an image onto a transparent screen doped with nanoparticles that selectively scatter light at the image wavelength(s) yields an image on the screen visible to an observer. Because the nanoparticles scatter light at only certain wavelengths, the screen is practically transparent under ambient light. Exemplary transparent scattering displays can be simple, inexpensive, scalable to large sizes, viewable over wide angular ranges, energy efficient, and transparent simultaneously.

  12. Missouri: Early Head Start Initiative

    ERIC Educational Resources Information Center

    Center for Law and Social Policy, Inc. (CLASP), 2012

    2012-01-01

    Missouri's Early Head Start/Child Care Partnership Project expands access to Early Head Start (EHS) services for children birth to age 3 by developing partnerships between federal Head Start, EHS contractors, and child care providers. Head Start and EHS contractors that participate in the initiative provide services through community child care…

  13. Porcine Head Response to Blast

    PubMed Central

    Shridharani, Jay K.; Wood, Garrett W.; Panzer, Matthew B.; Capehart, Bruce P.; Nyein, Michelle K.; Radovitzky, Raul A.; Bass, Cameron R. ‘Dale’

    2012-01-01

    Recent studies have shown an increase in the frequency of traumatic brain injuries related to blast exposure. However, the mechanisms that cause blast neurotrauma are unknown. Blast neurotrauma research using computational models has been one method to elucidate that response of the brain in blast, and to identify possible mechanical correlates of injury. However, model validation against experimental data is required to ensure that the model output is representative of in vivo biomechanical response. This study exposes porcine subjects to primary blast overpressures generated using a compressed-gas shock tube. Shock tube blasts were directed to the unprotected head of each animal while the lungs and thorax were protected using ballistic protective vests similar to those employed in theater. The test conditions ranged from 110 to 740 kPa peak incident overpressure with scaled durations from 1.3 to 6.9 ms and correspond approximately with a 50% injury risk for brain bleeding and apnea in a ferret model scaled to porcine exposure. Instrumentation was placed on the porcine head to measure bulk acceleration, pressure at the surface of the head, and pressure inside the cranial cavity. Immediately after the blast, 5 of the 20 animals tested were apneic. Three subjects recovered without intervention within 30 s and the remaining two recovered within 8 min following respiratory assistance and administration of the respiratory stimulant doxapram. Gross examination of the brain revealed no indication of bleeding. Intracranial pressures ranged from 80 to 390 kPa as a result of the blast and were notably lower than the shock tube reflected pressures of 300–2830 kPa, indicating pressure attenuation by the skull up to a factor of 8.4. Peak head accelerations were measured from 385 to 3845 G’s and were well correlated with peak incident overpressure (R2 = 0.90). One SD corridors for the surface pressure, intracranial pressure (ICP), and head acceleration are

  14. Inhibition of nuclear factor-{kappa}B and target genes during combined therapy with proteasome inhibitor bortezomib and reirradiation in patients with recurrent head-and-neck squamous cell carcinoma

    SciTech Connect

    Van Waes, Carter . E-mail: vanwaesc@nidcd.nih.gov; Chang, Angela A.; Lebowitz, Peter F.; Druzgal, Colleen H.; Chen, Zhong; Elsayed, Yusri A.; Sunwoo, John B.; Rudy, Susan; Morris, John C.; Mitchell, James B.; Camphausen, Kevin; Gius, David; Adams, Julian; Sausville, Edward A.; Conley, Barbara A.

    2005-12-01

    Purpose: To examine the effects the proteasome inhibitor bortezomib (VELCADE) on transcription factor nuclear factor-{kappa}B (NF-{kappa}B) and target genes and the feasibility of combination therapy with reirradiation in patients with recurrent head-and-neck squamous cell carcinoma (HNSCC). Methods and Materials: The tolerability and response to bortezomib 0.6 mg/m{sup 2} and 0.9 mg/m{sup 2} given twice weekly concurrent with daily reirradiation to 50-70 Gy was explored. Blood proteasome inhibition and NF-{kappa}B-modulated cytokines and factors were measured. Proteasome inhibition, nuclear localization of NF-{kappa}B phospho-p65, apoptosis, and expression of NF-{kappa}B-modulated mRNAs were compared in serial biopsies from accessible tumors. Results: The maximally tolerated dose was exceeded, and study was limited to 7 and 2 patients, respectively, given bortezomib 0.6 mg/m{sup 2} and 0.9 mg/m{sup 2}/dose with reirradiation. Grade 3 hypotension and hyponatremia were dose limiting. Mucositis was Grade 3 or less and was delayed. The mean blood proteasome inhibition at 1, 24, and 48 h after 0.6 mg/m{sup 2} was 32%, 16%, and 7% and after 0.9 mg/m{sup 2} was 56%, 26%, and 14%, respectively. Differences in proteasome and NF-{kappa}B activity, apoptosis, and expression of NF-{kappa}B-modulated cell cycle, apoptosis, and angiogenesis factor mRNAs were detected in 2 patients with minor tumor reductions and in serum NF-{kappa}B-modulated cytokines in 1 patient with a major tumor reduction. Conclusions: In combination with reirradiation, the maximally tolerated dose of bortezomib was exceeded at a dose of 0.6 mg/m{sup 2} and the threshold of proteasome inhibition. Although this regimen with reirradiation is not feasible, bortezomib induced detectable differences in NF-{kappa}B localization, apoptosis, and NF-{kappa}B-modulated genes and cytokines in tumor and serum in association with tumor reduction, indicating that other schedules of bortezomib combined with primary

  15. Hydration dependent studies of highly aligned multilayer lipid membranes by neutron scattering

    NASA Astrophysics Data System (ADS)

    Trapp, Marcus; Gutberlet, Thomas; Juranyi, Fanni; Unruh, Tobias; Demé, Bruno; Tehei, Moeava; Peters, Judith

    2010-10-01

    We investigated molecular motions on a picosecond timescale of 1,2-dimyristoyl-sn-glycero-3-phosphocholine (DMPC) model membranes as a function of hydration by using elastic and quasielastic neutron scattering. Two different hydrations corresponding to approximately nine and twelve water molecules per lipid were studied, the latter being the fully hydrated state. In our study, we focused on head group motions by using chain deuterated lipids. Information on in-plane and out-of-plane motions could be extracted by using solid supported DMPC multilayers. Our studies confirm and complete former investigations by König et al. [J. Phys. II (France) 2, 1589 (1992)] and Rheinstädter et al. [Phys. Rev. Lett. 101, 248106 (2008)] who described the dynamics of lipid membranes, but did not explore the influence of hydration on the head group dynamics as presented here. From the elastic data, a clear shift of the main phase transition from the Pβ ripple phase to the Lα liquid phase was observed. Decreasing water content moves the transition temperature to higher temperatures. The quasielastic data permit a closer investigation of the different types of head group motion of the two samples. Two different models are needed to fit the elastic incoherent structure factor and corresponding radii were calculated. The presented data show the strong influence hydration has on the head group mobility of DMPC.

  16. Standardization of light scattering measurements

    NASA Astrophysics Data System (ADS)

    Schröder, Sven; von Finck, Alexander; Duparré, Angela

    2015-10-01

    In every advanced optical system, light scattering caused by the imperfections of optical components sooner or later becomes an issue that needs to be addressed. Light scattering can be a critical factor for both the throughput and the imaging quality of optical systems. On a component level, the quantities to describe these effects are the scatter loss or total scattering (TS) and the scattering distribution function or angle-resolved light scattering (ARS). In the last decades, a number of instruments have been developed worldwide for the measurement of TS and ARS. However, numerous pitfalls have to be avoided to obtain objective, reliable, and reproducible measurement results. This is, in particular, true for low scatter levels of high-end optical components. Standard procedures that have to be both concise and easy to implement are thus of crucial importance for the optics community. This paper tries to give an overview on existing standards as well as an outlook on new standards that are still being developed. Special emphasis is put on ISO standards jointly developed, reviewed, and revised by the international experts in the field.

  17. Architecture of the Mediator head module.

    PubMed

    Imasaki, Tsuyoshi; Calero, Guillermo; Cai, Gang; Tsai, Kuang-Lei; Yamada, Kentaro; Cardelli, Francesco; Erdjument-Bromage, Hediye; Tempst, Paul; Berger, Imre; Kornberg, Guy Lorch; Asturias, Francisco J; Kornberg, Roger D; Takagi, Yuichiro

    2011-07-14

    Mediator is a key regulator of eukaryotic transcription, connecting activators and repressors bound to regulatory DNA elements with RNA polymerase II (Pol II). In the yeast Saccharomyces cerevisiae, Mediator comprises 25 subunits with a total mass of more than one megadalton (refs 5, 6) and is organized into three modules, called head, middle/arm and tail. Our understanding of Mediator assembly and its role in regulating transcription has been impeded so far by limited structural information. Here we report the crystal structure of the essential Mediator head module (seven subunits, with a mass of 223 kilodaltons) at a resolution of 4.3 ångströms. Our structure reveals three distinct domains, with the integrity of the complex centred on a bundle of ten helices from five different head subunits. An intricate pattern of interactions within this helical bundle ensures the stable assembly of the head subunits and provides the binding sites for general transcription factors and Pol II. Our structural and functional data suggest that the head module juxtaposes transcription factor IIH and the carboxy-terminal domain of the largest subunit of Pol II, thereby facilitating phosphorylation of the carboxy-terminal domain of Pol II. Our results reveal architectural principles underlying the role of Mediator in the regulation of gene expression. PMID:21725323

  18. Effects of Soccer Heading on Brain Structure and Function.

    PubMed

    Rodrigues, Ana Carolina; Lasmar, Rodrigo Pace; Caramelli, Paulo

    2016-01-01

    Soccer is the most popular sport in the world, with more than 265 million players worldwide, including professional and amateur ones. Soccer is unique in comparison to other sports, as it is the only sport in which participants purposely use their head to hit the ball. Heading is considered as an offensive or defensive move whereby the player's unprotected head is used to deliberately impact the ball and direct it during play. A soccer player can be subjected to an average of 6-12 incidents of heading the ball per competitive game, where the ball reaches high velocities. Moreover, in practice sessions, heading training, which involves heading the ball repeatedly at low velocities, is common. Although the scientific community, as well as the media, has focused on the effects of concussions in contact sports, the role of subconcussive impacts, as it can occur during heading, has recently gained attention, considering that it may represent an additional mechanism of cumulative brain injury. The purpose of this study is to review the existing literature regarding the effects of soccer heading on brain structure and function. Only in the last years, some investigations have addressed the impact of heading on brain structure, by using neuroimaging techniques. Similarly, there have been some recent studies investigating biochemical markers of brain injury in soccer players. There is evidence of association between heading and abnormal brain structure, but the data are still preliminary. Also, some studies have suggested that subconcussive head impacts, as heading, could cause cognitive impairment, whereas others have not corroborated this finding. Questions persist as to whether or not heading is deleterious to cognitive functioning. Further studies, especially with longitudinal designs, are needed to clarify the clinical significance of heading as a cause of brain injury and to identify risk factors. Such investigations might contribute to the establishment of safety

  19. Effects of Soccer Heading on Brain Structure and Function

    PubMed Central

    Rodrigues, Ana Carolina; Lasmar, Rodrigo Pace; Caramelli, Paulo

    2016-01-01

    Soccer is the most popular sport in the world, with more than 265 million players worldwide, including professional and amateur ones. Soccer is unique in comparison to other sports, as it is the only sport in which participants purposely use their head to hit the ball. Heading is considered as an offensive or defensive move whereby the player’s unprotected head is used to deliberately impact the ball and direct it during play. A soccer player can be subjected to an average of 6–12 incidents of heading the ball per competitive game, where the ball reaches high velocities. Moreover, in practice sessions, heading training, which involves heading the ball repeatedly at low velocities, is common. Although the scientific community, as well as the media, has focused on the effects of concussions in contact sports, the role of subconcussive impacts, as it can occur during heading, has recently gained attention, considering that it may represent an additional mechanism of cumulative brain injury. The purpose of this study is to review the existing literature regarding the effects of soccer heading on brain structure and function. Only in the last years, some investigations have addressed the impact of heading on brain structure, by using neuroimaging techniques. Similarly, there have been some recent studies investigating biochemical markers of brain injury in soccer players. There is evidence of association between heading and abnormal brain structure, but the data are still preliminary. Also, some studies have suggested that subconcussive head impacts, as heading, could cause cognitive impairment, whereas others have not corroborated this finding. Questions persist as to whether or not heading is deleterious to cognitive functioning. Further studies, especially with longitudinal designs, are needed to clarify the clinical significance of heading as a cause of brain injury and to identify risk factors. Such investigations might contribute to the establishment of safety

  20. Developing Fusarium head blight resistant wheat

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fusarium head blight, caused by Fusarium graminearum, is a major disease problem in wheat and barley around the world. During infection, F. graminearum produces trichothecene mycotoxins that act as virulence factors and cause a reduction in grain quality. Therefore, developing approaches to detoxi...

  1. Head Position Preference in the Human Newborn: A New Look.

    ERIC Educational Resources Information Center

    Ronnqvist, Louise; Hopkins, Brian

    1998-01-01

    Studied head position preference in 20 newborns differing by Cesarean or vaginal delivery and sex. Found that neither factor accounted for differences. The head turned right more often and was maintained longer in this position during quiet wakefulness, regardless of scoring method. When using global scoring, duration of midline position was…

  2. Head Start Teachers' Beliefs about Language and Literacy Instruction

    ERIC Educational Resources Information Center

    Hindman, Annemarie H.; Wasik, Barbara A.

    2008-01-01

    This study investigated the nature of Head Start teachers' beliefs about early literacy and the teacher background factors that relate to these beliefs. Twenty-eight Head Start teachers were given the Preschool Teacher Literacy Beliefs Questionnaire (TBQ) and a background questionnaire. Reliable belief subscales reflecting code, oral language,…

  3. Head segmentation in vertebrates

    PubMed Central

    Kuratani, Shigeru; Schilling, Thomas

    2008-01-01

    Classic theories of vertebrate head segmentation clearly exemplify the idealistic nature of comparative embryology prior to the 20th century. Comparative embryology aimed at recognizing the basic, primary structure that is shared by all vertebrates, either as an archetype or an ancestral developmental pattern. Modern evolutionary developmental (Evo-Devo) studies are also based on comparison, and therefore have a tendency to reduce complex embryonic anatomy into overly simplified patterns. Here again, a basic segmental plan for the head has been sought among chordates. We convened a symposium that brought together leading researchers dealing with this problem, in a number of different evolutionary and developmental contexts. Here we give an overview of the outcome and the status of the field in this modern era of Evo-Devo. We emphasize the fact that the head segmentation problem is not fully resolved, and we discuss new directions in the search for hints for a way out of this maze. PMID:20607135

  4. Lubricating the swordfish head.

    PubMed

    Videler, John J; Haydar, Deniz; Snoek, Roelant; Hoving, Henk-Jan T; Szabo, Ben G

    2016-07-01

    The swordfish is reputedly the fastest swimmer on Earth. The concave head and iconic sword are unique characteristics, but how they contribute to its speed is still unknown. Recent computed tomography scans revealed a poorly mineralised area near the base of the rostrum. Here we report, using magnetic resonance imaging and electron microscopy scanning, the discovery of a complex organ consisting of an oil-producing gland connected to capillaries that communicate with oil-excreting pores in the skin of the head. The capillary vessels transport oil to abundant tiny circular pores that are surrounded by denticles. The oil is distributed from the pores over the front part of the head. The oil inside the gland is identical to that found on the skin and is a mixture of methyl esters. We hypothesize that the oil layer, in combination with the denticles, creates a super-hydrophobic layer that reduces streamwise friction drag and increases swimming efficiency. PMID:27385753

  5. Scatter-based magnetic resonance elastography

    NASA Astrophysics Data System (ADS)

    Papazoglou, Sebastian; Xu, Chao; Hamhaber, Uwe; Siebert, Eberhard; Bohner, Georg; Klingebiel, Randolf; Braun, Jürgen; Sack, Ingolf

    2009-04-01

    Elasticity is a sensitive measure of the microstructural constitution of soft biological tissues and increasingly used in diagnostic imaging. Magnetic resonance elastography (MRE) uniquely allows in vivo measurement of the shear elasticity of brain tissue. However, the spatial resolution of MRE is inherently limited as the transformation of shear wave patterns into elasticity maps requires the solution of inverse problems. Therefore, an MRE method is introduced that avoids inversion and instead exploits shear wave scattering at elastic interfaces between anatomical regions of different shear compliance. This compliance-weighted imaging (CWI) method can be used to evaluate the mechanical consistency of cerebral lesions or to measure relative stiffness differences between anatomical subregions of the brain. It is demonstrated that CWI-MRE is sensitive enough to reveal significant elasticity variations within inner brain parenchyma: the caudate nucleus (head) was stiffer than the lentiform nucleus and the thalamus by factors of 1.3 ± 0.1 and 1.7 ± 0.2, respectively (P < 0.001). CWI-MRE provides a unique method for characterizing brain tissue by identifying local stiffness variations.

  6. Variation of patient dose in head CT.

    PubMed

    Smith, A; Shah, G A; Kron, T

    1998-12-01

    CT dose varies with both equipment related and operator dependent factors. Thermoluminescence dosimetry (TLD) was employed in two phantoms to investigate the variation in absorbed dose for head CT scans, using a cylindrical head CT dose phantom. Dose profiles were plotted and the computed tomography dose index (CTDI) calculated for a single 10 mm thick slice on 14 CT scanners. An anthropomorphic head phantom was also scanned from the base-of-skull to the vertex using 10/10 mm slices. The absorbed dose measured at the centre of the scan series is reported (Dmid). The mean CTDIw for the 14 scanners was 60.0 mGy, while the mean Dmid was 45.8 mGy. Dmid better represents the absorbed dose in human tissues. The CTDIw and Dmid normalized to mAs varied by up to a factor of 2.2 for the different scanners. Equipment related factors contribute to such variations. However, variations due to operator dependent factors such as the choice of exposure factors, scanning protocol and positioning technique must also be considered. When such factors are taken into account the absorbed dose received by the patient can vary considerably, by as much as 16.2 for lens dose. Increased awareness of the factors influencing CT dose and the standardization of scanning protocols is recommended. PMID:10319004

  7. Laser scattering by transcranial rat brain illumination

    NASA Astrophysics Data System (ADS)

    Sousa, Marcelo V. P.; Prates, Renato; Kato, Ilka T.; Sabino, Caetano P.; Suzuki, Luis C.; Ribeiro, Martha S.; Yoshimura, Elisabeth M.

    2012-06-01

    Due to the great number of applications of Low-Level-Laser-Therapy (LLLT) in Central Nervous System (CNS), the study of light penetration through skull and distribution in the brain becomes extremely important. The aim is to analyze the possibility of precise illumination of deep regions of the rat brain, measure the penetration and distribution of red (λ = 660 nm) and Near Infra-Red (NIR) (λ = 808 nm) diode laser light and compare optical properties of brain structures. The head of the animal (Rattus Novergicus) was epilated and divided by a sagittal cut, 2.3 mm away from mid plane. This section of rat's head was illuminated with red and NIR lasers in points above three anatomical structures: hippocampus, cerebellum and frontal cortex. A high resolution camera, perpendicularly positioned, was used to obtain images of the brain structures. Profiles of scattered intensities in the laser direction were obtained from the images. There is a peak in the scattered light profile corresponding to the skin layer. The bone layer gives rise to a valley in the profile indicating low scattering coefficient, or frontal scattering. Another peak in the region related to the brain is an indication of high scattering coefficient (μs) for this tissue. This work corroborates the use of transcranial LLLT in studies with rats which are subjected to models of CNS diseases. The outcomes of this study point to the possibility of transcranial LLLT in humans for a large number of diseases.

  8. Identification of the zinc-dependent endothelial cell binding protein for high molecular weight kininogen and factor XII: identity with the receptor that binds to the globular "heads" of C1q (gC1q-R).

    PubMed Central

    Joseph, K; Ghebrehiwet, B; Peerschke, E I; Reid, K B; Kaplan, A P

    1996-01-01

    High molecular weight kininogen (HK) and factor XII are known to bind to human umbilical vein endothelial cells (HUVEC) in a zinc-dependent and saturable manner indicating that HUVEC express specific binding site(s) for those proteins. However, identification and immunochemical characterization of the putative receptor site(s) has not been previously accomplished. In this report, we have identified a cell surface glycoprotein that is a likely candidate for the HK binding site on HUVECs. When solubilized HUVEC membranes were subjected to an HK-affinity column in the presence or absence of 50 microM ZnCl2 and the bound membrane proteins eluted, a single major protein peak was obtained only in the presence of zinc. SDS/PAGE analysis and silver staining of the protein peak revealed this protein to be 33 kDa and partial sequence analysis matched the NH2 terminus of gC1q-R, a membrane glycoprotein that binds to the globular "heads" of C1q. Two other minor proteins of approximately 70 kDa and 45 kDa were also obtained. Upon analysis by Western blotting, the 33-kDa band was found to react with several monoclonal antibodies (mAbs) recognizing different epitopes on gC1q-R. Ligand and dot blot analyses revealed zinc-dependent binding of biotinylated HK as well as biotinylated factor XII to the isolated 33-kDa HUVEC molecule as well as recombinant gC1q-R. In addition, binding of 125I-HK to HUVEC cells was inhibited by selected monoclonal anti-gC1q-R antibodies. C1q, however, did not inhibit 125I-HK binding to HUVEC nor did those monoclonals known to inhibit C1q binding to gC1q-R. Taken together, the data suggest that HK (and factor XII) bind to HUVECs via a 33-kDa cell surface glycoprotein that appears to be identical to gC1q-R but interact with a site on gC1q-R distinct from that which binds C1q. Images Fig. 1 Fig. 3 Fig. 4 Fig. 5 PMID:8710908

  9. The Influence of Head Motion on Intrinsic Functional Connectivity MRI

    PubMed Central

    Van Dijk, Koene R.A.; Sabuncu, Mert R.; Buckner, Randy L.

    2011-01-01

    Functional connectivity MRI (fcMRI) has been widely applied to explore group and individual differences. A confounding factor is head motion. Children move more than adults, older adults more than younger adults, and patients more than controls. Head motion varies considerably among individuals within the same population. Here we explored the influence of head motion on fcMRI estimates. Mean head displacement, maximum head displacement, the number of micro movements (> 0.1 mm), and head rotation were estimated in 1000 healthy, young adult subjects each scanned for two resting-state runs on matched 3T scanners. The majority of fcMRI variation across subjects was not linked to estimated head motion. However, head motion had significant, systematic effects on fcMRI network measures. Head motion was associated with decreased functional coupling in the default and frontoparietal control networks – two networks characterized by coupling among distributed regions of association cortex. Other network measures increased with motion including estimates of local functional coupling and coupling between left and right motor regions – a region pair sometimes used as a control in studies to establish specificity. Comparisons between groups of individuals with subtly different levels of head motion yielded difference maps that could be mistaken for neuronal effects in other contexts. These effects are important to consider when interpreting variation between groups and across individuals. PMID:21810475

  10. Hyperparathyroidism following head and neck irradiation

    SciTech Connect

    Rao, S.D.; Frame, B.; Miller, M.J.; Kleerskoper, M.; Block, M.A.; Parfitt, A.M.

    1980-02-01

    A history of head and neck irradiation in childhood or adolescence was found in 22 of 130 patients with primary hyperparathyroidism compared with only 12 of 400 control patients. Among 200 patients with a known history of childhood irradiation, biochemical or surgical evidence of hyperparathyroidism was found in ten, a prevalence of 5%. This is at least 30 times the prevalence of hyperparathyroidism in the general population. The data indicate that head and neck irradiation should be regarded as an important risk factor in the subsequent development of hyperparathyroidism.

  11. Dynamic structure factor [S(Q,ω)] of the S=1 quasi-one-dimensional Heisenberg antiferromagnet: Neutron-scattering study on AgVP2S6

    NASA Astrophysics Data System (ADS)

    Mutka, H.; Payen, C.; Molinié, P.; Soubeyroux, J. L.; Colombet, P.; Taylor, A. D.

    1991-07-01

    The spin correlations of the S=1 Heisenberg antiferromagnetic chains in AgVP2S6 have been studied by neutron scattering at temperatures of the order of T~10-2 J/kB. On the polycrystalline samples, with a careful choice of experimental conditions, we have observed a Haldane gap of Eg=26 meV at the antiferromagnetic point at q=π. The excitation spectra are consistent with a mode that has a spin-wave velocity C=150 meV and a correlation length ξ~=5.5, close to C/Eg. These results are in quantitative agreement with the predictions and numerical results on the Haldane state.

  12. Expressions for Form Factors for Inelastic Scattering and Charge Exchange in Plane-Wave, Distorted-Wave, and Coupled-Channels Reaction Formalisms

    SciTech Connect

    Dietrich, F S

    2006-09-25

    This document is intended to facilitate calculation of inelastic scattering and charge-exchange cross sections in a variety of reaction models, including the plane-wave and distorted-wave approximations and the full coupled-channels treatments. Expressions are given for the coupling potentials between the relevant channels in both coordinate and momentum space. In particular, it is expected that the plane-wave calculations should be useful as a check on the correctness of coupled-channels calculations. The Fourier transform methods used to calculate the plane-wave approximation cross sections are also intended to be used to generate the transition potentials for coupled-channels codes, using a folding model with local effective interactions. Specific expressions are given for calculating transition densities for the folding model in the random phase approximation (RPA).

  13. Loss of SOX2 expression induces cell motility via vimentin up-regulation and is an unfavorable risk factor for survival of head and neck squamous cell carcinoma.

    PubMed

    Bayo, Pilar; Jou, Adriana; Stenzinger, Albrecht; Shao, Chunxuan; Gross, Madeleine; Jensen, Alexandra; Grabe, Niels; Mende, Christel Herold; Rados, Pantelis Varvaki; Debus, Juergen; Weichert, Wilko; Plinkert, Peter K; Lichter, Peter; Freier, Kolja; Hess, Jochen

    2015-10-01

    Recurrent gain on chromosome 3q26 encompassing the gene locus for the transcription factor SOX2 is a frequent event in human squamous cell carcinoma, including head and neck squamous cell carcinoma (HNSCC). Numerous studies demonstrated that SOX2 expression and function is related to distinct aspects of tumor cell pathophysiology. However, the underlying molecular mechanisms are not well understood, and the correlation between SOX2 expression and clinical outcome revealed conflicting data. Transcriptional profiling after silencing of SOX2 expression in a HNSCC cell line identified a set of up-regulated genes related to cell motility (e.g. VIM, FN1, CDH2). The inverse regulation of SOX2 and aforementioned genes was validated in 18 independent HNSCC cell lines from different anatomical sites. The inhibition of cell migration and invasion by SOX2 was confirmed by constant or conditional gene silencing and accelerated motility of HNSCC cells after SOX2 silencing was partially reverted by down-regulation of vimentin. In a retrospective study, SOX2 expression was determined by immunohistochemical staining on tissue microarrays containing primary tumor specimens of two independent HNSCC patient cohorts. Low SOX2 expression was found in 19.3% and 44.9% of primary tumor specimens, respectively. Univariate analysis demonstrated a statistically significant correlation between low SOX2 protein levels and reduced progression-free survival (Cohort I 51 vs. 16 months; Cohort II 33 vs. 12 months) and overall survival (Cohort I 150 vs. 37 months; Cohort II 33 vs. 16 months). Multivariate Cox proportional hazard model analysis confirmed that low SOX2 expression serves as an independent prognostic marker for HNSCC patients. We conclude that SOX2 inhibits tumor cell motility in HNSCC cells and that low SOX2 expression serves as a prognosticator to identify HNSCC patients at high risk for treatment failure. PMID:26040981

  14. Radiation Dose to the Lens of the Eye from Computed Tomography Scans of the Head

    NASA Astrophysics Data System (ADS)

    Januzis, Natalie Ann

    factors were derived for each scanner individually, but also were derived with the combined data from the two scanners as a means to investigate the feasibility of a scanner-independent method. Using the scanner-independent method to derive the CTDIvol-to-lens dose conversion factor from the effective head diameter, most of the fitted lens dose values fell within 10-15% of the measured values from the phantom study, suggesting that this is a fairly accurate method of estimating lens dose from the CTDIvol with knowledge of the patient's head size. Second, the dose reduction potential of organ-based tube current modulation (OB-TCM) and its effect on the CTDIvol-to-lens dose estimation method was investigated. The lens dose was measured with MOSFET dosimeters placed within the same six anthropomorphic phantoms. The phantoms were scanned with the five clinical head CT protocols with OB-TCM enabled on the one scanner model at our institution equipped with this software. The average decrease in lens dose with OB-TCM ranged from 13.5 to 26.0%. Using the size-specific method to derive the CTDIvol-to-lens dose conversion factor from the effective head diameter for protocols with OB-TCM, the majority of the fitted lens dose values fell within 15-18% of the measured values from the phantom study. Third, the effect of gantry angulation on lens dose was investigated by measuring the lens dose with TLDs placed within the six anthropomorphic phantoms. The 2-dimensional spatial distribution of dose within the areas of the phantoms containing the orbit was measured with radiochromic film. A method was derived to determine the CTDIvol-to-lens dose conversion factor based upon distance from the primary beam scan range to the lens. The average dose to the lens region decreased substantially for almost all the phantoms (ranging from 67 to 92%) when the orbit was exposed to scattered radiation compared to the primary beam. The effectiveness of this method to reduce lens dose is highly

  15. Reactor pressure vessel vented head

    DOEpatents

    Sawabe, James K.

    1994-01-11

    A head for closing a nuclear reactor pressure vessel shell includes an arcuate dome having an integral head flange which includes a mating surface for sealingly mating with the shell upon assembly therewith. The head flange includes an internal passage extending therethrough with a first port being disposed on the head mating surface. A vent line includes a proximal end disposed in flow communication with the head internal passage, and a distal end disposed in flow communication with the inside of the dome for channeling a fluid therethrough. The vent line is fixedly joined to the dome and is carried therewith when the head is assembled to and disassembled from the shell.

  16. Head Start Curriculum Guide.

    ERIC Educational Resources Information Center

    Smith, Clare Coe; And Others

    One of a series of guides for preschool teachers and aides, the book offers a Head Start curriculum guide to help achieve goals regarding social behavior, general attitudes, academic skills, health, and parent development. Information on curriculum is divided into areas of bloc time outline, classroom arrangement, building concepts (such as…

  17. Sculpting Ceramic Heads.

    ERIC Educational Resources Information Center

    Sapiro, Maurice

    1983-01-01

    Clay sculpture is difficult to produce because of the requirements of kiln firing. The problems can be overcome by modeling the original manikin head and making a plaster mold, pressing molding slabs of clay into the plaster mold to form the hollow clay armature, and sculpting on the armature. (IS)

  18. Imaging of head trauma.

    PubMed

    Rincon, Sandra; Gupta, Rajiv; Ptak, Thomas

    2016-01-01

    Imaging is an indispensable part of the initial assessment and subsequent management of patients with head trauma. Initially, it is important for diagnosing the extent of injury and the prompt recognition of treatable injuries to reduce mortality. Subsequently, imaging is useful in following the sequelae of trauma. In this chapter, we review indications for neuroimaging and typical computed tomography (CT) and magnetic resonance imaging (MRI) protocols used in the evaluation of a patient with head trauma. We review the role of CT), the imaging modality of choice in the acute setting, and the role of MRI in the evaluation of patients with head trauma. We describe an organized and consistent approach to the interpretation of imaging of these patients. Important topics in head trauma, including fundamental concepts related to skull fractures, intracranial hemorrhage, parenchymal injury, penetrating trauma, cerebrovascular injuries, and secondary effects of trauma, are reviewed. The chapter concludes with advanced neuroimaging techniques for the evaluation of traumatic brain injury, including use of diffusion tensor imaging (DTI), functional MRI (fMRI), and MR spectroscopy (MRS), techniques which are still under development. PMID:27432678

  19. MULTIPLE SHAFT TOOL HEAD

    DOEpatents

    Colbert, H.P.

    1962-10-23

    An improved tool head arrangement is designed for the automatic expanding of a plurality of ferruled tubes simultaneously. A plurality of output shafts of a multiple spindle drill head are driven in unison by a hydraulic motor. A plurality of tube expanders are respectively coupled to the shafts through individual power train arrangements. The axial or thrust force required for the rolling operation is provided by a double acting hydraulic cylinder having a hollow through shaft with the shaft cooperating with an internally rotatable splined shaft slidably coupled to a coupling rigidly attached to the respectlve output shaft of the drill head, thereby transmitting rotary motion and axial thrust simultaneously to the tube expander. A hydraulic power unit supplies power to each of the double acting cylinders through respective two-position, four-way valves, under control of respective solenoids for each of the cylinders. The solenoids are in turn selectively controlled by a tool selection control unit which in turn is controlled by signals received from a programmed, coded tape from a tape reader. The number of expanders that are extended in a rolling operation, which may be up to 42 expanders, is determined by a predetermined program of operations depending upon the arrangement of the ferruled tubes to be expanded in the tube bundle. The tape reader also supplies dimensional information to a machine tool servo control unit for imparting selected, horizontal and/or vertical movement to the tool head assembly. (AEC)

  20. Scattering functions of Platonic solids

    SciTech Connect

    Li, Xin; Shew, Chwen-Yang; He, Lilin; Meilleur, Flora; Myles, Dean A A; Liu, Emily; Zhang, Yang; Smith, Greg; Herwig, Kenneth W; Pynn, Roger; Chen, Wei-Ren

    2011-01-01

    The single-particle small-angle scattering properties of five Platonic solids, including the tetrahedron, hexahedron, octahedron, dodecahedron and icosahedron, are systematically investigated. For each given geometry, the Debye spatial autocorrelation function, pair distance distribution function and intraparticle structure factor (form factor) are calculated and compared with the corresponding scattering function of a spherical reference system. From the theoretical models, the empirical relationship between the dodecahedral and icosahedral structural characteristics and those of the equivalent spheres is found. Moreover, the single-particle scattering properties of icosahedral and spherical shells with identical volume are investigated, and the prospect of using different data analysis approaches to explore their structural differences is presented and discussed.

  1. Scattering functions of Platonic solids

    SciTech Connect

    Chen, Wei-Ren; Herwig, Kenneth W; Li, Xin; Liu, Emily; Pynn, Roger; Shew, Chwen-Yang; Smith, Gregory Scott; Myles, Dean A A; He, Lilin; Meilleur, Flora

    2011-01-01

    In this report the single-particle scattering properties of five Platonic solids, including tetrahedron, hexahedron, octahedron, dodecahedron and icosahedron, are investigated in a systematic manner. For each given geometry, the Debye spatial autocorrelation function (r), pair distance distribution function (PDDF) p (r) and intraparticle structure factor (form factor) P (Q) are respectively calculated and compared to the corresponding scattering function of the spherical referential system. Based on our theoretical models, the empirical relationship between the dodecahedral and icosahedral structural characteristics and those of the equivalent spheres is found. Moreover, the single-particle scattering properties of the icosahedral and the spherical shells with the same volume are further investigated and the prospect of using different data analysis approaches to explore their structural difference is also presented and discussed.

  2. TH-A-18C-04: Ultrafast Cone-Beam CT Scatter Correction with GPU-Based Monte Carlo Simulation

    SciTech Connect

    Xu, Y; Bai, T; Yan, H; Ouyang, L; Wang, J; Pompos, A; Jiang, S; Jia, X; Zhou, L

    2014-06-15

    Purpose: Scatter artifacts severely degrade image quality of cone-beam CT (CBCT). We present an ultrafast scatter correction framework by using GPU-based Monte Carlo (MC) simulation and prior patient CT image, aiming at automatically finish the whole process including both scatter correction and reconstructions within 30 seconds. Methods: The method consists of six steps: 1) FDK reconstruction using raw projection data; 2) Rigid Registration of planning CT to the FDK results; 3) MC scatter calculation at sparse view angles using the planning CT; 4) Interpolation of the calculated scatter signals to other angles; 5) Removal of scatter from the raw projections; 6) FDK reconstruction using the scatter-corrected projections. In addition to using GPU to accelerate MC photon simulations, we also use a small number of photons and a down-sampled CT image in simulation to further reduce computation time. A novel denoising algorithm is used to eliminate MC scatter noise caused by low photon numbers. The method is validated on head-and-neck cases with simulated and clinical data. Results: We have studied impacts of photo histories, volume down sampling factors on the accuracy of scatter estimation. The Fourier analysis was conducted to show that scatter images calculated at 31 angles are sufficient to restore those at all angles with <0.1% error. For the simulated case with a resolution of 512×512×100, we simulated 10M photons per angle. The total computation time is 23.77 seconds on a Nvidia GTX Titan GPU. The scatter-induced shading/cupping artifacts are substantially reduced, and the average HU error of a region-of-interest is reduced from 75.9 to 19.0 HU. Similar results were found for a real patient case. Conclusion: A practical ultrafast MC-based CBCT scatter correction scheme is developed. The whole process of scatter correction and reconstruction is accomplished within 30 seconds. This study is supported in part by NIH (1R01CA154747-01), The Core Technology Research

  3. Head, Neck, and Oral Cancer

    MedlinePlus

    ... Neck and Oral Pathology Head, Neck and Oral Pathology Close to 42,000 Americans will be diagnosed ... Neck and Oral Pathology Head, Neck and Oral Pathology Close to 42,000 Americans will be diagnosed ...

  4. Intrabeam scattering in the HEB

    SciTech Connect

    Larson, D.J.

    1994-03-01

    A study of Intrabeam Scattering (IBS) in the High Energy Booster (HEB) is presented. Piwinski`s formulas for IBS are presented and evaluated for the HEB. A computer code written to evaluate Piwinski`s formulas is discussed. The result of the study is that IBS should not be a problem for the HEB, although the safety factor is not enormous.

  5. Heads Up to High School Sports

    MedlinePlus

    ... Juvenil HEADS UP to School Sports Online Concussion Training Coaches Parents Athletes Sports Officials HEADS UP to Schools School Nurses Teachers, Counselors, and School Professionals Parents HEADS UP ...

  6. Clinical implementation of intraoperative cone-beam CT in head and neck surgery

    NASA Astrophysics Data System (ADS)

    Daly, M. J.; Chan, H.; Nithiananthan, S.; Qiu, J.; Barker, E.; Bachar, G.; Dixon, B. J.; Irish, J. C.; Siewerdsen, J. H.

    2011-03-01

    A prototype mobile C-arm for cone-beam CT (CBCT) has been translated to a prospective clinical trial in head and neck surgery. The flat-panel CBCT C-arm was developed in collaboration with Siemens Healthcare, and demonstrates both sub-mm spatial resolution and soft-tissue visibility at low radiation dose (e.g., <1/5th of a typical diagnostic head CT). CBCT images are available ~15 seconds after scan completion (~1 min acquisition) and reviewed at bedside using custom 3D visualization software based on the open-source Image-Guided Surgery Toolkit (IGSTK). The CBCT C-arm has been successfully deployed in 15 head and neck cases and streamlined into the surgical environment using human factors engineering methods and expert feedback from surgeons, nurses, and anesthetists. Intraoperative imaging is implemented in a manner that maintains operating field sterility, reduces image artifacts (e.g., carbon fiber OR table) and minimizes radiation exposure. Image reviews conducted with surgical staff indicate bony detail and soft-tissue visualization sufficient for intraoperative guidance, with additional artifact management (e.g., metal, scatter) promising further improvements. Clinical trial deployment suggests a role for intraoperative CBCT in guiding complex head and neck surgical tasks, including planning mandible and maxilla resection margins, guiding subcranial and endonasal approaches to skull base tumours, and verifying maxillofacial reconstruction alignment. Ongoing translational research into complimentary image-guidance subsystems include novel methods for real-time tool tracking, fusion of endoscopic video and CBCT, and deformable registration of preoperative volumes and planning contours with intraoperative CBCT.

  7. Design and validation of novel scattering foils for modulated electron radiation therapy.

    PubMed

    Connell, T; Seuntjens, J

    2014-05-21

    Modulated Electron Radiation Therapy (MERT) continues to be an area of interest to various groups, however, the scattering foils used in beam flattening have not been optimized for this modality. In this work, the feasibility of novel scattering foils specifically designed for MERT is investigated using Monte Carlo methods. Different designs based on foil material, shape and thickness were analyzed. It was shown that low atomic number materials such as aluminum were optimal, while shaped foils such as those employed in current dual foil designs were not necessary. Aluminum foil thickness between 0.36 mm and 1.50 mm were capable of sufficiently broadening beams with energies between 12 MeV and 20 MeV respectively, with beams of lower energies receiving sufficient scatter from the treatment head components and air scatter. Finally, custom foils were manufactured based upon previously simulated designs and were placed into the beamline of a 2100 EX accelerator, and showed excellent agreement between the simulated and measured PDDs and profiles. Custom foils achieved higher dose rates on the central axis compared to the clinical foils by factors of 5.4, 4.9 and 4.5 for 12 MeV, 16 MeV and 20 MeV, respectively. PMID:24743426

  8. Design and validation of novel scattering foils for modulated electron radiation therapy

    NASA Astrophysics Data System (ADS)

    Connell, T.; Seuntjens, J.

    2014-05-01

    Modulated Electron Radiation Therapy (MERT) continues to be an area of interest to various groups, however, the scattering foils used in beam flattening have not been optimized for this modality. In this work, the feasibility of novel scattering foils specifically designed for MERT is investigated using Monte Carlo methods. Different designs based on foil material, shape and thickness were analyzed. It was shown that low atomic number materials such as aluminum were optimal, while shaped foils such as those employed in current dual foil designs were not necessary. Aluminum foil thickness between 0.36 mm and 1.50 mm were capable of sufficiently broadening beams with energies between 12 MeV and 20 MeV respectively, with beams of lower energies receiving sufficient scatter from the treatment head components and air scatter. Finally, custom foils were manufactured based upon previously simulated designs and were placed into the beamline of a 2100 EX accelerator, and showed excellent agreement between the simulated and measured PDDs and profiles. Custom foils achieved higher dose rates on the central axis compared to the clinical foils by factors of 5.4, 4.9 and 4.5 for 12 MeV, 16 MeV and 20 MeV, respectively.

  9. Multiphonon scattering from surfaces

    NASA Astrophysics Data System (ADS)

    Manson, J. R.; Celli, V.; Himes, D.

    1994-01-01

    We consider the relationship between several different formalisms for treating the multiphonon inelastic scattering of atomic projectiles from surfaces. Starting from general principles of formal scattering theory, the trajectory approximation to the scattering intensity is obtained. From the trajectory approximation, the conditions leading to the fast-collision approximation for multiquantum inelastic scattering are systematically derived.

  10. Minnesota: Early Head Start Initiatiive

    ERIC Educational Resources Information Center

    Center for Law and Social Policy, Inc. (CLASP), 2012

    2012-01-01

    Minnesota provides supplemental state funding to existing federal Head Start and Early Head Start (EHS) grantees to increase their capacity to serve additional infants, toddlers, and pregnant women. The initiative was started in 1997 when the state legislature earmarked $1 million of the general state Head Start supplemental funds for children…

  11. Maryland Early Head Start Initiative

    ERIC Educational Resources Information Center

    Center for Law and Social Policy, Inc. (CLASP), 2012

    2012-01-01

    Since 2000, Maryland has provided state supplemental funds to Head Start and Early Head Start (EHS) programs to improve access. Local EHS programs may use funds, through child care partnerships, to extend the EHS day or year. Maryland's approach to building on EHS includes: (1) Increase the capacity of existing Head Start and EHS programs to…

  12. MAGNETIC RECORDING HEAD

    DOEpatents

    Merrill, L.C.

    1958-06-17

    An electromagetic recording head is described for simultaneous recording of a plurality of signals within a small space on a magnetically semsitized medium. Basically the head structure comprises a non-magnetic centerpiece provided with only first and second groups of spaced cut-out slots respectively on opposite sides of the centerpiece. The two groups of slots are in parallel alignment and the slots of one group are staggered with respect to the slots of the other group so that one slot is not directly opposite another slot. Each slot has a magnet pole piece disposed therein and cooperating with a second pole and coil to provide a magnetic flux gap at the upper end of the slot. As a tape is drawn over the upper end of the centerpiece the individual magnetic circuits are disposed along its width to provide means for simultaneously recording information on separate portions, tracks. of the tape.

  13. Multilaser print head

    NASA Astrophysics Data System (ADS)

    Goodman, Douglas S.; Roblee, Jeffrey W.; Plummer, William T.; Clark, Peter P.

    1998-12-01

    This paper discusses the optical and opto-mechanical design of a new laser head developed at Polaroid for printing Helios binary film for printing high quality medical hard copy images. The head is part of an external drum printer for 14' X 17' film. The pixel size is 84 X 84 micrometer, produced by four lasers, with the smallest printable spot 3 X 6 micrometer, to produce 4096 gray levels. Two pixels side-by-side are simultaneously printed. The head has eight independent 840 nm diode lasers manufactured by Polaroid. Each laser emits up to 1.1 W over an emission length of about 100 micrometer, with a particularly uniform nearfield irradiance. The lasers are microlensed to equalize the divergences in the two principal meridians. Each packaged laser is aligned in a field-replaceable illuminator whose output beam, focused at infinity, is bore-sighted in a mechanical cylinder. The illuminators are arranged roughly radially. Eight lenses image the laser nearfields on a multi-facet mirror produced by diamond machining. The mirror facets truncate the beams to give the desired pixel shapes and separations. A reducing afocal relay images the mirror onto the film. The final element is a molded aspheric lens, mounted in an actuator to maintain focus on the film. The focusing unit also comprises a triangulation-based focus sensor. The alignment procedures and fixtures were devised concurrently with the head for manufacturing simplicity. The main physical structure is a casting, into which reference surfaces are machined. All optical subassemblies are attached to this casting, with a mixture of optical alignment and self-location. Semi-kinematic cylinder-in-V methodology is utilized. The active alignment steps are done in a sequence that tends to reduce errors from previous steps.

  14. [Bilateral caudate head infarcts].

    PubMed

    Kuriyama, N; Yamamoto, Y; Akiguchi, I; Oiwa, K; Nakajima, K

    1997-11-01

    We reported a 67-year-old woman with bilateral caudate head infarcts. She developed sudden mutism followed by abulia. She was admitted to our hospital 2 months after ictus for further examination. She showed prominent abulia and was inactive, slow and apathetic. Spontaneous activity and speech, immediate response to queries, spontaneous word recall and attention and persistence to complex programs were disturbed. Apparent motor disturbance, gait disturbance, motor aphasia, apraxia and remote memory disturbance were not identified. She seemed to be depressed but not sad. Brain CT and MRI revealed bilateral caudate head hemorrhagic infarcts including bilateral anterior internal capsules, in which the left lesion was more extensive than right one and involved the part of the left putamen. These infarct locations were thought to be supplied by the area around the medial striate artery including Heubner's arteries and the A1 perforator. Digital subtraction angiography showed asymptomatic right internal carotid artery occlusion. She bad had hypertension, diabetes mellitus and atrial fibrillation and also had a left atrium with a large diameter. The infarcts were thought to be caused by cardioembolic occlusion to the distal portion of the left internal carotid artery. Although some variations of vasculature at the anterior communicating artery might contribute to bilateral medial striate artery infarcts, we could not demonstrate such abnormalities by angiography. Bilateral caudate head infarcts involving the anterior internal capsule may cause prominent abulia. The patient did not improve by drug and rehabilitation therapy and died suddenly a year after discharge. PMID:9503974

  15. Heads or tails: how do chemically substituted fullerenes melt?

    PubMed

    Armstrong, Jeff; Mukhopadhyay, Sanghamitra; Bresme, Fernando; Fernandez-Alonso, Felix

    2016-06-29

    We address the question as to whether the melting of chemically substituted fullerenes is driven by the dynamics of the fullerene moiety (the head) or the substituted sub-unit (the tail). To this end, we have performed quasielastic neutron-scattering experiments and classical molecular-dynamics simulations as a function of temperature on the prototypical fullerene derivative phenyl-C61-butyric acid methyl ester. To enable a direct and quantitative comparison between experimental and simulation data, dynamic structure factors for the latter have been calculated from atomic trajectories and further convolved with the known instrument response. A detailed analysis of the energy- and momentum-transfer dependence of this observable in the quasielastic regime shows that melting is entirely driven by temperature-activated tail motions. We also provide quantitative estimates of the activation energy for this process as the material first enters a plastic-crystalline phase, followed by the emergence of a genuine liquid at higher temperatures. PMID:27087579

  16. Human epidermal growth factor receptor 3 (HER3) blockade with U3-1287/AMG888 enhances the efficacy of radiation therapy in lung and head and neck carcinoma.

    PubMed

    Li, Chunrong; Brand, Toni M; Iida, Mari; Huang, Shyhmin; Armstrong, Eric A; van der Kogel, Albert; Wheeler, Deric L

    2013-09-01

    HER3 is a member of the epidermal growth factor receptor (EGFR) family of receptor tyrosine kinases. In the present study, we investigated the capacity of the HER3 blocking antibody, U3-1287/AMG888, to modulate the in vitro and in vivo radiation response of human squamous cell carcinomas of the lung and head and neck. We screened a battery of cell lines from these tumors for HER3 expression and demonstrated that all cell lines screened exhibited expression of HER3. Importantly, U3-1287/AMG888 treatment could block both basal HER3 activity and radiation induced HER3 activation. Proliferation assays indicated that HER3 blockade could decrease the proliferation of both HNSCC cell line SCC6 and NSCLC cell line H226. Further, we demonstrated that U3-1287/AMG888 can sensitize cells to radiation in clonogenic survival assays, in addition to increasing DNA damage as detected via λ-H2AX immunofluorescence. To determine if U3-1287/AMG888 could enhance radiation sensitivity in vivo we performed tumor growth delay experiments using SCC6, SCC1483, and H226 xenografts. The results of these experiments indicated that the combination of U3-1287/AMG888 and radiation could decrease tumor growth in studies using single or fractionated doses of radiation. Analysis of HER3 expression in tumor samples indicated that radiation treatment activated HER3 in vivo and that U3-1287/AMG888 could abrogate this activation. Immunohistochemistry analysis of SCC6 tumors treated with both U3-1287/AMG888 and a single dose of radiation demonstrated that various cell survival and proliferation markers could be reduced. Collectively our findings suggest that U3-1287/AMG888 in combination with radiation has an impact on cell and tumor growth by increasing DNA damage and cell death. These findings suggest that HER3 may play an important role in response to radiation therapy and blocking its activity in combination with radiation may be of therapeutic benefit in human tumors. PMID:23998444

  17. Scattering Solar Thermal Concentrators

    SciTech Connect

    Giebink, Noel C.

    2015-01-31

    concentrator optical efficiency was found to decrease significantly with increasing aperture width beyond 0.5 m due to parasitic waveguide out-coupling loss and low-level absorption that become dominant at larger scale. A heat transfer model was subsequently implemented to predict collector fluid heat gain and outlet temperature as a function of flow rate using the optical model as a flux input. It was found that the aperture width size limitation imposed by the optical efficiency characteristics of the waveguide limits the absolute optical power delivered to the heat transfer element per unit length. As compared to state-of-the-art parabolic trough CPV system aperture widths approaching 5 m, this limitation leads to an approximate factor of order of magnitude increase in heat transfer tube length to achieve the same heat transfer fluid outlet temperature. The conclusion of this work is that scattering solar thermal concentration cannot be implemented at the scale and efficiency required to compete with the performance of current parabolic trough CSP systems. Applied within the alternate context of CPV, however, the results of this work have likely opened up a transformative new path that enables quasi-static, high efficiency CPV to be implemented on rooftops in the form factor of traditional fixed-panel photovoltaics.

  18. The relationship between occupations and head and neck cancers.

    PubMed Central

    Pinar, Tevfik; Akdur, Recep; Tuncbilek, Arslan; Altundag, Kadri; Cengiz, Mustafa

    2007-01-01

    OBJECTIVE: The objective of this study was to investigate the relationship between occupation and head and neck cancers. PATIENTS AND METHODS: In this case-control study, 206 Turkish patients with head and neck cancers comprised the case group. The control group consisted of 206 age- and sex-matched patients without malignant disease. All patients completed a questionnaire regarding occupation; tobacco and alcohol consumption; educational status; and history of any systemic disease, benign head and neck disease, and cancer among family members. High-risk jobs were considered those in the industries of construction, wood, mining, metal, chemistry and agriculture. RESULTS: Patients with head and neck cancers worked in high-risk occupations more frequently than did controls [odds ratio (OR): 3.42, p<0.05]. Cancer risk decreased with the increase in time interval between quitting the high-risk job and time of interview. Smokers were at higher risk than nonsmokers (OR: 3.33, p<0.05). The risk was also higher in patients who drank alcohol regularly (OR: 1.59, p<0.05). However, occupation was found to be an independent high-risk factor for head and neck cancers in regression analysis. Frequency of benign head and neck disease and family history of cancer were not significant risk factors (p>0.05). CONCLUSION: Our analysis showed that occupation and smoking were significant independent risk factors for the development of head and neck cancers among workers. PMID:17304970

  19. Quantifying entanglement with scattering experiments

    NASA Astrophysics Data System (ADS)

    Marty, O.; Epping, M.; Kampermann, H.; Bruß, D.; Plenio, M. B.; Cramer, M.

    2014-03-01

    We show how the entanglement contained in states of spins arranged on a lattice may be lower bounded with observables arising in scattering experiments. We focus on the partial differential cross section obtained in neutron scattering from magnetic materials but our results are sufficiently general such that they may also be applied to, e.g., optical Bragg scattering from ultracold atoms in optical lattices or from ion chains. We discuss resonating valence bond states and ground and thermal states of experimentally relevant models—such as the Heisenberg, Majumdar-Ghosh, and XY models—in different geometries and with different spin numbers. As a by-product, we find that for the one-dimensional XY model in a transverse field such measurements reveal factorization and the quantum phase transition at zero temperature.

  20. Efficient scatter distribution estimation and correction in CBCT using concurrent Monte Carlo fitting

    SciTech Connect

    Bootsma, G. J.; Verhaegen, F.; Jaffray, D. A.

    2015-01-15

    Purpose: X-ray scatter is a significant impediment to image quality improvements in cone-beam CT (CBCT). The authors present and demonstrate a novel scatter correction algorithm using a scatter estimation method that simultaneously combines multiple Monte Carlo (MC) CBCT simulations through the use of a concurrently evaluated fitting function, referred to as concurrent MC fitting (CMCF). Methods: The CMCF method uses concurrently run MC CBCT scatter projection simulations that are a subset of the projection angles used in the projection set, P, to be corrected. The scattered photons reaching the detector in each MC simulation are simultaneously aggregated by an algorithm which computes the scatter detector response, S{sub MC}. S{sub MC} is fit to a function, S{sub F}, and if the fit of S{sub F} is within a specified goodness of fit (GOF), the simulations are terminated. The fit, S{sub F}, is then used to interpolate the scatter distribution over all pixel locations for every projection angle in the set P. The CMCF algorithm was tested using a frequency limited sum of sines and cosines as the fitting function on both simulated and measured data. The simulated data consisted of an anthropomorphic head and a pelvis phantom created from CT data, simulated with and without the use of a compensator. The measured data were a pelvis scan of a phantom and patient taken on an Elekta Synergy platform. The simulated data were used to evaluate various GOF metrics as well as determine a suitable fitness value. The simulated data were also used to quantitatively evaluate the image quality improvements provided by the CMCF method. A qualitative analysis was performed on the measured data by comparing the CMCF scatter corrected reconstruction to the original uncorrected and corrected by a constant scatter correction reconstruction, as well as a reconstruction created using a set of projections taken with a small cone angle. Results: Pearson’s correlation, r, proved to be a

  1. Head-Neck Taper Corrosion in Hip Arthroplasty

    PubMed Central

    Hussenbocus, S.; Kosuge, D.; Solomon, L. B.; Howie, D. W.; Oskouei, R. H.

    2015-01-01

    Modularity at the head-neck junction of the femoral component in THA became popular as a design feature with advantages of decreasing implant inventory and allowing adjustment of leg length, offset, and soft tissue balancing through different head options. The introduction of a new modular interface to femoral stems that were previously monoblock, or nonmodular, comes with the potential for corrosion at the taper junction through mechanically assisted crevice corrosion. The incidence of revision hip arthroplasty is on the rise and along with improved wear properties of polyethylene and ceramic, use of larger femoral head sizes is becoming increasingly popular. Taper corrosion appears to be related to all of its geometric parameters, material combinations, and femoral head size. This review article discusses the pathogenesis, risk factors, clinical assessment, and management of taper corrosion at the head-neck junction. PMID:25954757

  2. Measuring head circumference

    PubMed Central

    Harris, Susan R.

    2015-01-01

    Abstract Objective To provide an evidence-based update emphasizing the importance of measuring head circumference (HC) in infants, with a focus on microcephaly. Quality of evidence PubMed and EMBASE (OvidSP) were searched. Search terms used were head circumference and infants and measurement; microcephaly and infants and measurement; idiopathic microcephaly and infants; and congenital microcephaly and infants. Most of the references for this review were published in 2000 or later. Most evidence is level II. Main message Serial measurement of HC should be incorporated into routine well-child care. Measure the distance around the back of the child’s head with a nonelastic tape measure held above the eyebrows and ears, and plot the measurement on an age- and sex-appropriate growth chart. Microcephaly is HC more than 2 SD below the mean. The most common disability associated with microcephaly is intellectual delay; other common concomitant conditions include epilepsy, cerebral palsy, language delay, strabismus, ophthalmologic disorders, and cardiac, renal, urinary tract, and skeletal anomalies. An interdisciplinary approach to microcephaly is warranted. Although there are no specific interventions to enhance brain growth, dietary or surgical interventions might be helpful in some cases. Infants with microcephaly who show developmental delays might benefit from early intervention programs or developmental physical and occupational therapy. Conclusion Early identification of HC concerns by family physicians can be a critical first step in identifying disorders such as microcephaly, leading to referral to pediatric specialists and, as needed, provision of family-centred early intervention services. PMID:26505062

  3. Reactor vessel head permanent shield

    SciTech Connect

    Hankinson, M.F.; Leduc, R.J.; Richard, J.W.; Malandra, L.J.

    1989-05-09

    A nuclear reactor is described comprising: a nuclear reactor pressure vessel closure head; control rod drive mechanisms (CRDMs) disposed within the closure head so as to project vertically above the closure head; cooling air baffle means surrounding the control rod drive mechanisms for defining cooling air paths relative to the control rod drive mechanisms; means defined within the periphery of the closure head for accommodating fastening means for securing the closure head to its associated pressure vessel; lifting lugs fixedly secured to the closure head for facilitating lifting and lowering movements of the closure head relative to the pressure vessel; lift rods respectively operatively associated with the plurality of lifting lugs for transmitting load forces, developed during the lifting and lowering movements of the closure head, to the lifting lugs; upstanding radiation shield means interposed between the cooling air baffle means and the periphery of the enclosure head of shielding maintenance personnel operatively working upon the closure head fastening means from the effects of radiation which may emanate from the control rod drive mechanisms and the cooling air baffle means; and connecting systems respectively associated with each one of the lifting lugs and each one of the lifting rods for connecting each one of the lifting rods to a respective one of each one of the lifting lugs, and for simultaneously connecting a lower end portion of the upstanding radiation shield means to each one of the respective lifting lugs.

  4. Radiation Dose to the Lens of the Eye from Computed Tomography Scans of the Head

    NASA Astrophysics Data System (ADS)

    Januzis, Natalie Ann

    factors were derived for each scanner individually, but also were derived with the combined data from the two scanners as a means to investigate the feasibility of a scanner-independent method. Using the scanner-independent method to derive the CTDIvol-to-lens dose conversion factor from the effective head diameter, most of the fitted lens dose values fell within 10-15% of the measured values from the phantom study, suggesting that this is a fairly accurate method of estimating lens dose from the CTDIvol with knowledge of the patient's head size. Second, the dose reduction potential of organ-based tube current modulation (OB-TCM) and its effect on the CTDIvol-to-lens dose estimation method was investigated. The lens dose was measured with MOSFET dosimeters placed within the same six anthropomorphic phantoms. The phantoms were scanned with the five clinical head CT protocols with OB-TCM enabled on the one scanner model at our institution equipped with this software. The average decrease in lens dose with OB-TCM ranged from 13.5 to 26.0%. Using the size-specific method to derive the CTDIvol-to-lens dose conversion factor from the effective head diameter for protocols with OB-TCM, the majority of the fitted lens dose values fell within 15-18% of the measured values from the phantom study. Third, the effect of gantry angulation on lens dose was investigated by measuring the lens dose with TLDs placed within the six anthropomorphic phantoms. The 2-dimensional spatial distribution of dose within the areas of the phantoms containing the orbit was measured with radiochromic film. A method was derived to determine the CTDIvol-to-lens dose conversion factor based upon distance from the primary beam scan range to the lens. The average dose to the lens region decreased substantially for almost all the phantoms (ranging from 67 to 92%) when the orbit was exposed to scattered radiation compared to the primary beam. The effectiveness of this method to reduce lens dose is highly

  5. Head motions while riding roller coasters: Implications for brain injury

    PubMed Central

    Chickola, Larry; Smith, Douglas H.

    2009-01-01

    The risk of traumatic brain injury (TBI) while riding roller coasters has received substantial attention. Case reports of TBI around the time of riding roller coasters have led many medical professionals to assert that the high gravitational forces (G-forces) induced by roller coasters pose a significant TBI risk. Head injury research, however, has shown that G-forces alone cannot predict TBI. Established head injury criterions and procedures were employed to compare the potential of TBI between daily activities and roller coaster riding. Three dimensional head motions were measured during three different roller coaster rides, a pillow fight, and car crash simulations. Data was analyzed and compared to published data using similar analyses of head motions. An 8.05m/s car crash lead to the largest head injury criterion measure (HIC15) of 28.1 and head impact factor (HIP) of 3.41, over six times larger than the roller coaster rides of 4.1 and 0.36. Notably, the linear and rotational components of head acceleration during roller coaster rides were milder than those induced by many common activities. As such, there appears to be an extremely low risk of TBI due to the head motions induced by roller coaster rides. PMID:19901817

  6. Optics as Scattering

    ERIC Educational Resources Information Center

    di Francia, Giuliano Toraldo

    1973-01-01

    The art of deriving information about an object from the radiation it scatters was once limited to visible light. Now due to new techniques, much of the modern physical science research utilizes radiation scattering. (DF)

  7. Reactor pressure vessel vented head

    DOEpatents

    Sawabe, J.K.

    1994-01-11

    A head for closing a nuclear reactor pressure vessel shell includes an arcuate dome having an integral head flange which includes a mating surface for sealingly mating with the shell upon assembly therewith. The head flange includes an internal passage extending therethrough with a first port being disposed on the head mating surface. A vent line includes a proximal end disposed in flow communication with the head internal passage, and a distal end disposed in flow communication with the inside of the dome for channeling a fluid therethrough. The vent line is fixedly joined to the dome and is carried therewith when the head is assembled to and disassembled from the shell. 6 figures.

  8. Firing Properties of Rat Lateral Mammillary Single Units: Head Direction, Head Pitch, and Angular Head Velocity

    PubMed Central

    Stackman, Robert W.; Taube, Jeffrey S.

    2006-01-01

    Many neurons in the rat anterodorsal thalamus (ADN) and postsubiculum (PoS) fire selectively when the rat points its head in a specific direction in the horizontal plane, independent of the animal’s location and ongoing behavior. The lateral mammillary nuclei (LMN) are interconnected with both the ADN and PoS and, therefore, are in a pivotal position to influence ADN/PoS neurophysiology. To further understand how the head direction (HD) cell signal is generated, we recorded single neurons from the LMN of freely moving rats. The majority of cells discharged as a function of one of three types of spatial correlates: (1) directional heading, (2) head pitch, or (3) angular head velocity (AHV). LMN HD cells exhibited higher peak firing rates and greater range of directional firing than that of ADN and PoS HD cells. LMN HD cells were modulated by angular head velocity, turning direction, and anticipated the rat’s future HD by a greater amount of time (~95 msec) than that previously reported for ADN HD cells (~25 msec). Most head pitch cells discharged when the rostrocaudal axis of the rat’s head was orthogonal to the horizontal plane. Head pitch cell firing was independent of the rat’s location, directional heading, and its body orientation (i.e., the cell discharged whenever the rat pointed its head up, whether standing on all four limbs or rearing). AHV cells were categorized as fast or slow AHV cells depending on whether their firing rate increased or decreased in proportion to angular head velocity. These data demonstrate that LMN neurons code direction and angular motion of the head in both horizontal and vertical planes and support the hypothesis that the LMN play an important role in processing both egocentric and allocentric spatial information. PMID:9787007

  9. Head Lice: Diagnosis

    MedlinePlus

    ... Treatment FAQs Malathion FAQs Epidemiology & Risk Factors Disease Biology Diagnosis Treatment Prevention & Control Resources for Health Professionals ... Frequently Asked Questions (FAQs) Epidemiology & Risk Factors Disease Biology Diagnosis Treatment Prevention & Control Resources for Health Professionals ...

  10. Head Lice: Disease

    MedlinePlus

    ... Treatment FAQs Malathion FAQs Epidemiology & Risk Factors Disease Biology Diagnosis Treatment Prevention & Control Resources for Health Professionals ... Frequently Asked Questions (FAQs) Epidemiology & Risk Factors Disease Biology Diagnosis Treatment Prevention & Control Resources for Health Professionals ...

  11. Head and neck considerations in the elderly patient.

    PubMed

    Robinson, D S

    1994-04-01

    An evaluation of head and neck surgery in the elderly reveals that old age should not be an issue in determining the course of treatment. The risks, complication rates, mortality rates, and final outcome of older patients are similar to those seen in younger patients with head and neck cancer. Although age itself should not be an issue in setting forth a plan of treatment, underlying co-morbid factors such as cardiovascular and respiratory illness that may occur with advanced age should be taken into careful account. As our population becomes older, surgeons dealing with head and neck cancer will need to give special consideration to this age group. PMID:8165475

  12. Extracting the frequencies of the pinna spectral notches in measured head related impulse responses

    NASA Astrophysics Data System (ADS)

    Raykar, Vikas C.; Duraiswami, Ramani; Yegnanarayana, B.

    2005-07-01

    The head related impulse response (HRIR) characterizes the auditory cues created by scattering of sound off a person's anatomy. The experimentally measured HRIR depends on several factors such as reflections from body parts (torso, shoulder, and knees), head diffraction, and reflection/diffraction effects due to the pinna. Structural models (Algazi et al., 2002; Brown and Duda, 1998) seek to establish direct relationships between the features in the HRIR and the anatomy. While there is evidence that particular features in the HRIR can be explained by anthropometry, the creation of such models from experimental data is hampered by the fact that the extraction of the features in the HRIR is not automatic. One of the prominent features observed in the HRIR, and one that has been shown to be important for elevation perception, are the deep spectral notches attributed to the pinna. In this paper we propose a method to robustly extract the frequencies of the pinna spectral notches from the measured HRIR, distinguishing them from other confounding features. The method also extracts the resonances described by Shaw (1997). The techniques are applied to the publicly available CIPIC HRIR database (Algazi et al., 2001c). The extracted notch frequencies are related to the physical dimensions and shape of the pinna.

  13. The potential and limitations of utilising head impact injury models to assess the likelihood of significant head injury in infants after a fall.

    PubMed

    Cory, C Z; Jones, M D; James, D S; Leadbeatter, S; Nokes, L D

    2001-12-01

    The use of engineering principles in assessing head injury scenarios is of increasing significance in investigations into suspected child abuse. A fall scenario is often given as the history for a head injury to an infant. This paper addresses the basic engineering principles and factors to be considered when calculating the severity of a head impact after free-fall. The application of head injury models (HIMs) to ascertain the forces involved in childhood head injuries from impact is also discussed. Previous studies including Duhaime et al. [J. Neurosurg. 66 (1987) 409] and Nokes et al. [Forensic Sci. Int. 79 (1995) 85] have utilised HIMs for this purpose: this paper reviews those models most widely documented.The HIM currently considered the 'state-of-the-art' is the head injury criterion (HIC) and it is suggested that this model should be utilised for assessing head impact injury in child abuse cases where appropriate. PMID:11728733

  14. Head Injury With Subsequent, Intermittent, Nonschizophrenic, Psychotic Symptoms and Violence

    PubMed Central

    Bell, Carl C.; Kelly, Ruby P.

    1987-01-01

    A young, black, adult woman presented to an outpatient clinic for treatment with a history of intermittent, nonschizophrenic, psychotic symptoms. Blacks, because of their situational sociology, may be more predisposed to severe head injuries, and this acquired biologic factor may be, in part, responsible for the high rates of black-on-black murder. The use of beta blockers is discussed as an adjunct in the treatment of violence occurring in patients with a past history of severe head injury. PMID:3694693

  15. Chryse 'Alien Head'

    NASA Technical Reports Server (NTRS)

    2005-01-01

    26 January 2004 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows an impact crater in Chryse Planitia, not too far from the Viking 1 lander site, that to seems to resemble a bug-eyed head. The two odd depressions at the north end of the crater (the 'eyes') may have formed by wind or water erosion. This region has been modified by both processes, with water action occurring in the distant past via floods that poured across western Chryse Planitia from Maja Valles, and wind action common occurrence in more recent history. This crater is located near 22.5oN, 47.9oW. The 150 meter scale bar is about 164 yards long. Sunlight illuminates the scene from the left/lower left.

  16. NASA head sworn in

    NASA Astrophysics Data System (ADS)

    James C. Fletcher was sworn in on May 12, 1986, as administrator of the National Aeronautics and Space Administration (NASA). At a news conference after he was sworn in, Fletcher said that NASA would deal with both its technical problems and its procedural problems before the shuttle will fly again. According to press accounts, he stressed that funds should be made available to replace the Challenger orbiter, which was lost in an explosion on January 28.Fletcher, who had also headed the agency from 1971 to 1977, succeeds James M. Beggs, who was indicted in December 1985 for conspiring to defraud the federal government while serving as a senior executive at the General Dynamics Corporation.

  17. Head of Administration

    NASA Astrophysics Data System (ADS)

    2005-03-01

    Purpose and scope of the position: The main task is to provide efficient administrative services and advice to the Director General, Division Leaders and to staff members in the scientific and technical areas in the fields of financial planning and accounting, personnel management, purchasing, legal and contractual matters, information systems and building and site maintenance. As a member of the ESO Management the Head of Administration contributes essentially to the development of the overall policy, strategic planning, relations to the members of the personnel and maintains professional contacts at highest level outside the Organisation. ESO employs in total approximately 650 staff members and the Administration Division comprises the Administration at the Headquarters in Garching near Munich and the Administration in Santiago (Chile). The successful candidate will be supported by some 50 qualified staff members.

  18. Electromagnetic inverse scattering

    NASA Technical Reports Server (NTRS)

    Bojarski, N. N.

    1972-01-01

    A three-dimensional electromagnetic inverse scattering identity, based on the physical optics approximation, is developed for the monostatic scattered far field cross section of perfect conductors. Uniqueness of this inverse identity is proven. This identity requires complete scattering information for all frequencies and aspect angles. A nonsingular integral equation is developed for the arbitrary case of incomplete frequence and/or aspect angle scattering information. A general closed-form solution to this integral equation is developed, which yields the shape of the scatterer from such incomplete information. A specific practical radar solution is presented. The resolution of this solution is developed, yielding short-pulse target resolution radar system parameter equations. The special cases of two- and one-dimensional inverse scattering and the special case of a priori knowledge of scatterer symmetry are treated in some detail. The merits of this solution over the conventional radar imaging technique are discussed.

  19. Materials for a Stirling engine heater head

    NASA Technical Reports Server (NTRS)

    Noble, J. E.; Lehmann, G. A.; Emigh, S. G.

    1990-01-01

    Work done on the 25-kW advanced Stirling conversion system (ASCS) terrestrial solar program in establishing criteria and selecting materials for the engine heater head and heater tubes is described. Various mechanisms contributing to incompatibility between materials are identified and discussed. Large thermal gradients, coupled with requirements for long life (60,000 h at temperature) and a large number of heatup and cooldown cycles (20,000) drive the design from a structural standpoint. The pressurized cylinder is checked for creep rupture, localized yielding, reverse plasticity, creep and fatigue damage, and creep ratcheting, in addition to the basic requirements for bust and proof pressure. In general, creep rupture and creep and fatigue interaction are the dominant factors in the design. A wide range of materials for the heater head and tubes was evaluated. Factors involved in the assessment were strength and effect on engine efficiency, reliability, and cost. A preliminary selection of Inconel 713LC for the heater head is based on acceptable structural properties but driven mainly by low cost. The criteria for failure, the structural analysis, and the material characteristics with basis for selection are discussed.

  20. San Andreas fault zone head waves near Parkfield, California

    SciTech Connect

    Ben-Zion, Y.; Malin, P. Univ. of California, Santa Barbara, CA )

    1991-03-29

    Microearthquakes seismograms from the borehole seismic network on the San Andreas Fault near Parkfield, California, provide three lines of evidence that first P arrivals are head waves refracted along the cross-fault material contrast. First, the travel time difference between these arrivals and secondary phases identified as direct P waves scales linearly with the source-receiver distance. Second, these arrivals have the emergent wave character associated in theory and practice with refracted head waves instead of the sharp first breaks associated with direct P arrivals. Third, the first motion polarities of the emergent arrivals are reversed from those of the direct P waves as predicted by the theory of fault zone head waves for slip on the San Andreas fault. The presence of fault zone head waves in local seismic network data may help account for scatter in earthquake locations and source mechanisms. The fault zone head waves indicate that the velocity contrast across the San Andreas fault near Parkfield is approximately 4 percent. Further studies of these waves may provide a way of assessing changes in the physical state of the fault system.

  1. San andreas fault zone head waves near parkfield, california.

    PubMed

    Ben-Zion, Y; Malin, P

    1991-03-29

    Microearthquake seismograms from the borehole seismic network on the San Andreas fault near Parkfield, California, provide three lines of evidence that first P arrivals are "head" waves refracted along the cross-fault material contrast. First, the travel time difference between these arrivals and secondary phases identified as direct P waves scales linearly with the source-receiver distance. Second, these arrivals have the emergent wave character associated in theory and practice with refracted head waves instead of the sharp first breaks associated with direct P arrivals. Third, the first motion polarities of the emergent arrivals are reversed from those of the direct P waves as predicted by the theory of fault zone head waves for slip on the San Andreas fault. The presence of fault zone head waves in local seismic network data may help account for scatter in earthquake locations and source mechanisms. The fault zone head waves indicate that the velocity contrast across the San Andreas fault near Parkfield is approximately 4 percent. Further studies of these waves may provide a way of assessing changes in the physical state of the fault system. PMID:17793143

  2. Dual-Head Robotic Welder

    NASA Technical Reports Server (NTRS)

    Beard, Gary S.

    1990-01-01

    Robotic welder uses two welding heads simultaneously. Developed for assembly of "hot dog" shell on main injector for Space Shuttle main engine, concept applicable to other, similarly rounded or contoured workpieces. Opposed heads reduce distortion and stress in opposed weld joints and speed up welding operations.

  3. Kansas: Early Head Start Initiative

    ERIC Educational Resources Information Center

    Center for Law and Social Policy, Inc. (CLASP), 2012

    2012-01-01

    Kansas Early Head Start (KEHS) provides comprehensive services following federal Head Start Program Performance Standards for pregnant women and eligible families with children from birth to age 4. KEHS was implemented in 1998 using Child Care and Development Block Grant (CCDBG) quality set-aside dollars augmented by a transfer of federal…

  4. Cutting Head for Ultrasonic Lithotripsy

    NASA Technical Reports Server (NTRS)

    Angulo, Earl D. (Inventor); Goodfriend, Roger (Inventor)

    1989-01-01

    A cutting head for attachment to the end of the wire probe of an ultrasonic kidney stone disintegration instrument. The cutting head has a plurality of circumferentially arranged teeth formed at one end thereof to provide a cup-shaped receptacle for kidney stones encountered during the disintegration procedure. An integral reduced diameter collar diminishes stress points in the wire and reduces breakage thereof.

  5. Vision Screening For Head Starters.

    ERIC Educational Resources Information Center

    Foley, Celia

    To determine which children in the Head Start program may have vision problems, Head Start teachers and staff do vision "screening." This booklet demonstrates how to do the screening using the Snellen "E Chart." Trouble signs that the test administrator should be aware of are listed, and vision scores are explained simply. Amblyopia is defined,…

  6. Nebraska: Early Head Start Initiative

    ERIC Educational Resources Information Center

    Center for Law and Social Policy, Inc. (CLASP), 2012

    2012-01-01

    Since 1999, Nebraska's Early Head Start Infant/Toddler Quality Initiative has supported Early Head Start (EHS) and community child care partnerships to improve the quality and professionalism of infant and toddler care. EHS programs apply to receive funding to establish partnerships with center-based or home-based child care.The initiative has…

  7. The Acquisition of [Head] Movement.

    ERIC Educational Resources Information Center

    Pye, Clifton

    An analysis of one theory of the acquisition of head movement by children is presented, using longitudinal data from the Mayan language, K'iche'. This theory assumes that children would just require positive evidence of head movement in the input language to instantiate the constructions of their own grammar. The Incorporation Theory addresses the…

  8. Interview with Joe F. Head

    ERIC Educational Resources Information Center

    West, Kim

    2008-01-01

    This article presents an interview with Joe F. Head, Dean of University Admissions and Enrollment Services at Kennesaw State University (KSU) in Georgia, who has more than 35 years of experience in admissions and enrollment services. After completing an M.Ed. in higher education at Georgia Southern University, Head immediately landed a position as…

  9. The Start of Head Start

    ERIC Educational Resources Information Center

    Neugebauer, Roger

    2010-01-01

    The creation of the Head Start program occurred at break-neck speed with many dramatic turns and many colorful players. No one tells the story better than Edward Zigler in "Head Start: The Inside Story of America's Most Successful Educational Experiment"--a detailed and personal, behind the scenes look at the program's inception. From this…

  10. Head-Up Displays and Attention Capture

    NASA Technical Reports Server (NTRS)

    Prinzel, Lawrence J., III; Risser, Matthew

    2004-01-01

    The primary role of head-up displays (HUDs) is to provide primary flight, navigation, and guidance information to the pilot in a forward field-of-view on a head-up transparent screen. Therefore, this theoretically allows for optimal control of an aircraft through the simultaneous scanning of both instrument data and the out-the-window scene. However, despite significant aviation safety benefits afforded by HUDs, a number of accidents have shown that their use does not come without costs. The human factors community has identified significant issues related to the pilot distribution of near and far domain attentional resources because of the compellingness of symbology elements on the HUD; a concern termed, attention or cognitive capture. The paper describes the phenomena of attention capture and presents a selected survey of the literature on the etiology and potential prescriptions.

  11. Idiopathic head tremor in English bulldogs.

    PubMed

    Guevar, Julien; De Decker, Steven; Van Ham, Luc M L; Fischer, Andrea; Volk, Holger A

    2014-02-01

    Idiopathic head tremor (IHT) syndrome is a recognized but poorly characterized movement disorder in English bulldogs (EBs). The data analyzed were collected via a detailed online questionnaire and video recordings. Thirty-eight percent of the population demonstrated IHT. The first presentation was early in life. There was no sex or neutered status predisposition. The condition disappeared with time in 50% of the cases. The direction of the head movement was vertical or horizontal. The number of episodes per day and the duration of the episodes were greatly variable. The majority of episodes occurred at rest. Most of the episodes were unpredictable. And there was no alteration of the mental status for most dogs during the episodes. Stress has been reported as a suspected trigger factor. IHT in EBs can be considered an idiopathic paroxysmal movement disorder. PMID:24375621

  12. Head Start Impact Study: First Year Findings

    ERIC Educational Resources Information Center

    Puma, Michael; Bell, Stephen; Cook, Ronna; Heid, Camilla; Lopez, Michael

    2005-01-01

    The Congressionally-mandated Head Start Impact Study is being conducted across 84 nationally representative grantee/delegate agencies. Approximately 5,000 newly entering 3- and 4-year-old children applying for Head Start were randomly assigned to either a Head Start group that had access to Head Start program services or to a non-Head Start group…

  13. Stereotactic Body Radiotherapy for Head and Neck Tumors

    ClinicalTrials.gov

    2016-04-18

    Squamous Cell Carcinoma of the Head and Neck; Nasopharyngeal Carcinoma; Salivary Gland Cancer; Head and Neck Sarcoma; Paraganglioma of Head and Neck; Chordoma of Head and Neck; Chondrosarcoma of Head and Neck; Angiofibroma of Head and Neck

  14. Granular structure determined by terahertz scattering

    NASA Astrophysics Data System (ADS)

    Born, Philip; Rothbart, Nick; Sperl, Matthias; Hübers, Heinz-Wilhelm

    2014-05-01

    Light scattering from particles reveals static and dynamical information about the particles and their correlations. Such methods are particularly powerful when the wavelength of the light is chosen similar to the sizes and distances of the particles. To apply scattering to investigate granular matter in particular —or other objects of similar submillimeter size— light of suitable wavelength in the terahertz regime needs to be chosen. By using a quantum cascade laser in a benchtop setup we determine the angle-dependent scattering of spherical particles as well as coffee powder and sugar grains. The scattering from single particles can be interpreted by form factors derived within the Mie theory. In addition, collective correlations can be extracted as static structure factors and compared to recent computer simulations.

  15. Magnetized stimulated scattering in pulsar winds

    NASA Technical Reports Server (NTRS)

    Sincell, Mark W.; Krolik, Julian H.

    1992-01-01

    The effects of stimulated scattering on a collimated high brightness temperature beam of photons traversing a relativistically streaming magnetized plasma are studied. Under the assumption that the center of the photon beam is parallel to the bulk motion, we calculate the scattering rate as a function of the angular spread of the beam and the Lorentz factor gamma. Magnetization changes the photon recoil, without which stimulated scattering has no effect. It also introduces a strong dependence on frequency and polarization: if the photon frequency matches the electron cyclotron frequency, the scattering rate of photons polarized perpendicular to the magnetic field can be substantially enhanced relative to Thomson, and if the photon frequency is much less than the cyclotron frequency, the scattering is suppressed. Applying these calculations to pulsars, we find that stimulated scattering of the radio beam in the magnetized wind believed to exist outside the light cylinder can substantially alter the spectrum and polarization state of the radio signal. We suggest that the scattering rate is so high in some pulsars that the ability of the radio signal to penetrate the pulsar magnetosphere requires modification of either the conventional model of the magnetosphere or assumptions about the effects of stimulated scattering upon a beam.

  16. Turbidity Current Head Mixing

    NASA Astrophysics Data System (ADS)

    Hernandez, David; Sanchez, Miguel Angel; Medina, Pablo

    2010-05-01

    A laboratory experimental set - up for studying the behaviour of sediment in presence of a turbulent field with zero mean flow is compared with the behaviour of turbidity currents [1] . Particular interest is shown on the initiation of sediment motion and in the sediment lift - off. The behaviour of the turbidity current in a flat ground is compared with the zero mean flow oscilating grid generated turbulence as when wave flow lifts off suspended sediments [2,3]. Some examples of the results obtained with this set-up relating the height of the head of the turbidity current to the equilibrium level of stirred lutoclines are shown. A turbulent velocity u' lower than that estimated by the Shield diagram is required to start sediment motion. The minimum u' required to start sediment lift - off, is a function of sediment size, cohesivity and resting time. The lutocline height depends on u', and the vorticity at the lutocline seems constant for a fixed sediment size [1,3]. Combining grid stirring and turbidty current head shapes analyzed by means of advanced image analysis, sediment vertical fluxes and settling speeds can be measured [4,5]. [1] D. Hernandez Turbulent structure of turbidity currents and sediment transport Ms Thesis ETSECCPB, UPC. Barcelona 2009. [2] A. Sánchez-Arcilla; A. Rodríguez; J.C. Santás; J.M. Redondo; V. Gracia; R. K'Osyan; S. Kuznetsov; C. Mösso. Delta'96 Surf-zone and nearshore measurements at the Ebro Delta. A: International Conference on Coastal Research through large Scale Experiments (Coastal Dynamics '97). University of Plymouth, 1997, p. 186-187. [3] P. Medina, M. A. Sánchez and J. M. Redondo. Grid stirred turbulence: applications to the initiation of sediment motion and lift-off studies Physics and Chemistry of the Earth, Part B: Hydrology, Oceans and Atmosphere. 26, Issue 4, 2001, Pages 299-304 [4] M.O. Bezerra, M. Diez, C. Medeiros, A. Rodriguez, E. Bahia., A. Sanchez-Arcilla and J.M. Redondo. Study on the influence of waves on

  17. Roles of scattered radiation in SRIXE

    SciTech Connect

    Hanson, A.L.

    1988-01-01

    The scattering of x-rays is the major source of background and hence is a limiting factor in the minimum detectable limits available with SRIXE measurements. The scattering can be utilized for normalizing the net peak areas to fluctuations in sample thickness or mass on a relative basis or on a comparative basis. Even then measurement of the scattered x-rays should be made at backward angles. Measurement at forward angles should be avoided because of diffraction problems. The uncertainties in the measurement of an absolute intensity of the x-rays can be extremely large.

  18. Benign paroxysmal positional vertigo and head position during sleep.

    PubMed

    Shigeno, Kohichiro; Ogita, Hideaki; Funabiki, Kazuo

    2012-01-01

    To determine whether any particular head positions during sleep are associated with BPPV, head position during sleep was monitored for 3 days in 50 BPPV patients after the disappearance of positional nystagmus and in 25 normal control subjects. A gravity sensor was attached to the center of the subject's forehead at home. The positional angle of the head was measured at 5-second intervals during sleep. In BPPV, the posterior semicircular canal was involved in 40 patients and the lateral semicircular canal in 10 patients. Recurrence was found in 22 of 50 BPPV patients. BPPV patients with recurrence were significantly more likely to sleep in the affected-ear-down 45-degree head position than were patients with no history of recurrence (P< 0.02). When the head is in the affected-ear-down 45-degree head position, the non-ampullated half of the posterior semicircular canal and the non-ampullated half of the lateral semicircular canal are nearly in the earth-vertical position, making it easier for detached otoconia to fall into the posterior or lateral semicircular canal and to agglomerate and attain a certain size in the lowest portion of each semicircular canal. Our findings showed that the affected-ear-down 45-degree head position during sleep could be an etiological factor of BPPV, more particularly in patients with recurrent BPPV. PMID:23142834

  19. In-Plane Scattering In Glass And Niobium Oxide Waveguides

    NASA Astrophysics Data System (ADS)

    Brandt, Gerald B.

    1981-02-01

    Scattered light which remains in an optical waveguide to be guided to the detector is an important limiting factor to the performance of integrated optical devices. In sputtered glass and niobium oxide wavegu ides the principal mechanisms for scattering are refractive index variations in the wave-guide and surface roughness of the waveguide. Theories for scattering from surface roughness, in the regime expected for these wavegu ides, predict that the wavelength variation of the scattering should be proportional to the inverse square of the wavelength. Theory for scattering from refractive index variations predicts a wavelength dependence ranging from inverse fourth power of the wavelength to no dependence upon wavelength, when the range of possible scattering diameters is varied from small to le ge with respect to the optical wavelength. Experiments on a number of relatively lossy wavegu ides indicate that there is little relation between overall waveguide loss and the magnitude of the scattering in the near forward direction. Furthermore, overall loss and in-plane scattering have different variations with wavelength suggesting that the mechanisms involved in loss and scat-tering are different. Waveguide surface preparation prior to sputtering ap-pears to be an important factor in determining overall quality, but more as it influences the bulk properties of the waveguide film than as a direct scattering mechanism. Homogeneity of the waveguide film appears to be the controlling factor in production of low scatter wavegu ides.

  20. Head and Neck Cancer: Symptoms and Signs

    MedlinePlus

    ... Symptoms and Signs Request Permissions Print to PDF Head and Neck Cancer - Symptoms and Signs Approved by the Cancer. ... Cancer Research and Advocacy Survivorship Blog About Us Head and Neck Cancer Guide Cancer.Net Guide Head and Neck ...

  1. Keeping Your Head On Target

    PubMed Central

    Wong, Aaron L.; Zee, David S.; Jinnah, H. A.

    2013-01-01

    The mechanisms by which the human brain controls eye movements are reasonably well understood, but those for the head less so. Here, we show that the mechanisms for keeping the head aimed at a stationary target follow strategies similar to those for holding the eyes steady on stationary targets. Specifically, we applied the neural integrator hypothesis that originally was developed for holding the eyes still in eccentric gaze positions to describe how the head is held still when turned toward an eccentric target. We found that normal humans make head movements consistent with the neural integrator hypothesis, except that additional sensory feedback is needed, from proprioceptors in the neck, to keep the head on target. We also show that the complicated patterns of head movements in patients with cervical dystonia can be predicted by deficits in a neural integrator for head motor control. These results support ideas originally developed from animal studies that suggest fundamental similarities between oculomotor and cephalomotor control, as well as a conceptual framework for cervical dystonia that departs considerably from current clinical views. PMID:23825431

  2. Eye and head motion during head turns in spaceflight

    NASA Technical Reports Server (NTRS)

    Thornton, William E.; Uri, John J.; Moore, Thomas P.; Pool, Sam L.

    1988-01-01

    Eye-head motion was studied pre-, in- and postflight during single voluntary head turns. A transient increase in vestibulo-ocular reflex (VOR) gain occurred early in the flight, but later trended toward normal. This increased gain was produced by a relative increase in eye counterrotation velocity. Asymmetries in gain with right and left turns also occurred, caused by asymmetries in eye counterrotation velocities. These findings were remarkably similar to those from Soviet primate studies using gaze fixation targets, except the human study trended more rapidly toward normal. These findings differ substantially from those measuring VOR gain by head oscillation, in which no significant changes were found inflight. No visual disturbances were noted in either test condition or in normal activities. These head turn studies are the only ones to date documenting any functional change in VOR in weightlessness.

  3. Adding Insult to Injury: Nonconvulsive Seizures in Abusive Head Trauma.

    PubMed

    Greiner, Mary V; Greiner, Hansel M; Caré, Marguerite M; Owens, Deanna; Shapiro, Robert; Holland, Katherine

    2015-11-01

    The primary objectives of this study were to determine the prevalence of nonconvulsive seizures and nonconvulsive status epilepticus in patients with abusive head trauma who underwent electroencephalography (EEG) monitoring and to describe predictive factors for this population. Children with a diagnosis of abusive head trauma were studied retrospectively to determine the rate of EEG monitoring, the rate of nonconvulsive seizures and nonconvulsive status epilepticus, and the associated neuroimaging findings. Over 11 years, 73 of 199 (36.8%) children with abusive head trauma had electroencephalography monitoring performed. Of these, 20 (27.4%) had nonconvulsive seizures and 3 (4.1%) had nonconvulsive status epilepticus. The presence of subarachnoid hemorrhage and cortical T2 / fluid-attenuated inversion recovery signal abnormalities were both significantly associated with the presence of nonconvulsive seizures / nonconvulsive status epilepticus. Nonconvulsive seizures are relatively common in abusive head trauma and may go unrecognized. Specific neuroimaging characteristics increase the likelihood of nonconvulsive seizures on EEG. PMID:25900138

  4. Multiple scattering tomography.

    PubMed

    Modregger, Peter; Kagias, Matias; Peter, Silvia; Abis, Matteo; Guzenko, Vitaliy A; David, Christian; Stampanoni, Marco

    2014-07-11

    Multiple scattering represents a challenge for numerous modern tomographic imaging techniques. In this Letter, we derive an appropriate line integral that allows for the tomographic reconstruction of angular resolved scattering distributions, even in the presence of multiple scattering. The line integral is applicable to a wide range of imaging techniques utilizing various kinds of probes. Here, we use x-ray grating interferometry to experimentally validate the framework and to demonstrate additional structural sensitivity, which exemplifies the impact of multiple scattering tomography. PMID:25062159

  5. Kaon-nucleus scattering

    NASA Technical Reports Server (NTRS)

    Hong, Byungsik; Maung, Khin Maung; Wilson, John W.; Buck, Warren W.

    1989-01-01

    The derivations of the Lippmann-Schwinger equation and Watson multiple scattering are given. A simple optical potential is found to be the first term of that series. The number density distribution models of the nucleus, harmonic well, and Woods-Saxon are used without t-matrix taken from the scattering experiments. The parameterized two-body inputs, which are kaon-nucleon total cross sections, elastic slope parameters, and the ratio of the real to the imaginary part of the forward elastic scattering amplitude, are presented. The eikonal approximation was chosen as our solution method to estimate the total and absorptive cross sections for the kaon-nucleus scattering.

  6. Environment scattering in GADRAS.

    SciTech Connect

    Thoreson, Gregory G.; Mitchell, Dean James; Theisen, Lisa Anne; Harding, Lee T.

    2013-09-01

    Radiation transport calculations were performed to compute the angular tallies for scattered gamma-rays as a function of distance, height, and environment. Green's Functions were then used to encapsulate the results a reusable transformation function. The calculations represent the transport of photons throughout scattering surfaces that surround sources and detectors, such as the ground and walls. Utilization of these calculations in GADRAS (Gamma Detector Response and Analysis Software) enables accurate computation of environmental scattering for a variety of environments and source configurations. This capability, which agrees well with numerous experimental benchmark measurements, is now deployed with GADRAS Version 18.2 as the basis for the computation of scattered radiation.

  7. Cutting Head for Ultrasonic Lithotripsy

    NASA Technical Reports Server (NTRS)

    Angulo, E. D.; Goodfriend, R.

    1987-01-01

    Kidney stones lodged in urinary tract disintegrated with increased safety and efficiency by cutting head attached to end of vibrated wire probe. Aligns probe with stone and enables probe to vibrate long enough to disintegrate stone. Design of cutting head reduces risk of metal-fatigue-induced breakage of probe tip leaving metal fragments in urinary tract. Teeth of cutting head both seat and fragment kidney stone, while extension of collar into catheter lessens mechanical strain in probe wire, increasing probe life and lessening danger of in situ probe breakage.

  8. Topiramate Responsive Exploding Head Syndrome

    PubMed Central

    Palikh, Gaurang M.; Vaughn, Bradley V.

    2010-01-01

    Exploding head syndrome is a rare phenomenon but can be a significant disruption to quality of life. We describe a 39-year-old female with symptoms of a loud bang and buzz at sleep onset for 3 years. EEG monitoring confirmed these events occurred in transition from stage 1 sleep. This patient reported improvement in intensity of events with topiramate medication. Based on these results, topiramate may be an alternative method to reduce the intensity of events in exploding head syndrome. Citation: Palikh GM; Vaughn BV. Topiramate responsive exploding head syndrome. J Clin Sleep Med 2010;6(4):382-383. PMID:20726288

  9. Anaphylaxis Due to Head Injury

    PubMed Central

    Bruner, Heather C.; Bruner, David I.

    2015-01-01

    Both anaphylaxis and head injury are often seen in the emergency department, but they are rarely seen in combination. We present a case of a 30-year-old woman who presented with anaphylaxis with urticaria and angioedema following a minor head injury. The patient responded well to intramuscular epinephrine without further complications or airway compromise. Prior case reports have reported angioedema from hereditary angioedema during dental procedures and maxillofacial surgery, but there have not been any cases of first-time angioedema or anaphylaxis due to head injury. PMID:25987924

  10. Positron scattering from vinyl acetate

    NASA Astrophysics Data System (ADS)

    Chiari, L.; Zecca, A.; Blanco, F.; García, G.; Brunger, M. J.

    2014-09-01

    Using a Beer-Lambert attenuation approach, we report measured total cross sections (TCSs) for positron scattering from vinyl acetate (C4H6O2) in the incident positron energy range 0.15-50 eV. In addition, we also report an independent atom model with screening corrected additivity rule computation results for the TCSs, differential and integral elastic cross sections, the positronium formation cross section and inelastic integral cross sections. The energy range of these calculations is 1-1000 eV. While there is a reasonable qualitative correspondence between measurement and calculation for the TCSs, in terms of the energy dependence of those cross sections, the theory was found to be a factor of ˜2 larger in magnitude at the lower energies, even after the measured data were corrected for the forward angle scattering effect.

  11. Generalized Rayleigh scattering. II. Matrix source functions.

    NASA Astrophysics Data System (ADS)

    Ivanov, V. V.; Kasaurov, A. M.; Loskutov, V. M.; Viik, T.

    1995-11-01

    Numerical and analytical data are presented on the matrix source functions S(τ) of the standard problem of multiple generalized Rayleigh scattering (GRS) in homogeneous semi-infinite atmospheres with uniformly distributed embedded primary sources of partially polarized radiation. The source matrices S(τ) are found by the discrete-ordinate solution of the relevant 2x2 matrix transfer equation and by albedo shifting technique, which is a version of the accelerated {LAMBDA}-iteration approach. The dependence of the solution of the matrix transfer equation on the parameters of the problem of multiple molecular scattering, albedo of single scattering λ_I_ and depolarization factor W, is carefully considered. (The value W=1 corresponds to Rayleigh scattering, while for scalar isotropic scattering W=0). From the pair of the parameters (λ_I_, W) we switch to (λ_I_, λ_Q_), with λ_Q_=0.7Wλ_I_, and instead of the physically natural domain of the parameter values, λ_Iin[0,1], λ_ Qin[0,0.7λ_I_], in GRS we consider a wider one, λ_ I_, λ_Qin[0,1]. On the plane with the axes (λ_I_, λ_Q_), or the λ-plane, there is a one-parameter family of curves, the isopols, along which S(0) remains constant. The λ-plane and the isopols are the basic instruments in our analysis. Along with presenting the numerical data we discuss the asymptotic behavior of S(τ) for τ->{infinity}. It is shown that the matrix counterpart of the usual scalar conservative isotropic scattering is not the ordinary conservative Rayleigh scattering (λ_I_=1, λ_ Q_=0.7), but the biconservative scattering, i.e., scattering with λ_I_=λ_Q_=1. The analysis of the remarkable properties of biconservative scattering naturally leads to matrix generalizations of the Hopf-Bronstein relation, the Hopf constant etc.

  12. Head-Up Tilt.

    PubMed

    Xu, Jinyi; Yang, Lihong; Zhang, Qiang; Li, Shuaibing; Qiao, Zihao; Fang, Ying; Zhao, Guihua; Wang, Qingyi; Liu, Guanghui

    2015-01-01

    Autonomic dysfunction has been associated with paroxysmal atrial fibrillation (PAF). The head-up tilt test (HUTT) is an important diagnostic tool for autonomic dysfunction. The aim of this study was to examine atrial fibrillation recurrence after RFCA by performing HUTT. A total of 488 consecutive patients with PAF who underwent RFCA were prospectively enrolled. HUTT was positive in 154 (31.6%) patients after a mean follow-up of 22.7 ± 3.5 months, and 163 (33.4%) had a recurrence. HUTT positive was significantly higher in PAF patients with recurrence compared to those without (68 (41.7%) versus 86 (26.5%), P < 0.001). Multivariate Cox regression analysis revealed that HUTT positive (HR: 1.96; 95% CI: 1.49-2.48, P < 0.001), left atrial diameter (HR: 1.77; 95%CI: 1.15-2.11, P = 0.004), AF duration (HR: 1.27; 95%CI: 0.98-1.83, P = 0.014), and sleep apnea (HR: 1.02; 95%CI: 0.81-1.53, P = 0.032) were independent predictors of clinical recurrence after RFCA. The success rate of ablation was 70.4% in patients in the HUTT negative group compared with 58.4% in patients in the HUTT positive group (log-rank P = 0.006). Patients with a positive headup tilt test were at an increased risk of AF recurrence after catheter ablation. Our results suggest that HUTT was a significant predictor for AF recurrence after catheter ablation for PAF. PMID:26370369

  13. The Drosophila fork head domain protein crocodile is required for the establishment of head structures.

    PubMed Central

    Häcker, U; Kaufmann, E; Hartmann, C; Jürgens, G; Knöchel, W; Jäckle, H

    1995-01-01

    The fork head (fkh) domain defines the DNA-binding region of a family of transcription factors which has been implicated in regulating cell fate decisions across species lines. We have cloned and molecularly characterized the crocodile (croc) gene which encodes a new family member from Drosophila. croc is expressed in the head anlagen of the blastoderm embryo under the control of the anterior, the dorsoventral and the terminal maternal organizer systems. The croc mutant phenotype indicates that the croc wild-type gene is required to function as an early patterning gene in the anterior-most blastoderm head segment anlage and for the establishment of a specific head skeletal structure that derives from the non-adjacent intercalary segment at a later stage of embryogenesis. As an early patterning gene, croc exerts unusual properties which do not allow it to be grouped among the established segmentation genes. A single-site mutation within the croc fkh domain, which causes a replacement of the first out of four conserved amino acid residues thought to be involved in the coordinate binding of Mg2+, abolishes the DNA binding of the protein in vitro. In view of the resulting lack-of-function mutant phenotype, it appears likely that metal binding by the affected region of the fkh domain is crucial for proper folding of the DNA-binding structure. Images PMID:7489720

  14. Head and neck cancer in two American presidents: Case reports.

    PubMed

    Weinberg, Mea A; Wang, Beverly

    2011-01-01

    Two former U.S. presidents, Ulysses S. Grant and Grover Cleveland, were diagnosed with head and neck cancer in 1884 and 1893, respectively. A historical review of the risk factors, diagnoses, and treatments is examined and compared with modern-day interpretations. A comparison was made using the original diagnoses with today's equivalent diagnosis. Different treatment outcomes at the time of the original diagnoses relative to today's treatment are reviewed. Clinicians must be familiar with risk factors, signs, symptoms, diagnosis, and treatment of head and neck cancer. PMID:22313921

  15. Knowledge and Screening of Head and Neck Cancer Among American Indians in South Dakota

    PubMed Central

    Deschler, Daniel; Sargent, Michele; Emerick, Kevin; Guadagnolo, B. Ashleigh; Petereit, Daniel

    2015-01-01

    Objectives. We established the level of awareness of risk factors and early symptoms of head and neck cancer among American Indians in South Dakota and determined whether head and neck cancer screening detected clinical findings in this population. Methods. We used the European About Face survey. We added questions about human papillomavirus, a risk factor for head and neck cancer, and demographics. Surveys were administered at 2 public events in 2011. Participants could partake in a head and neck cancer screening at the time of survey administration. Results. Of the 205 American Indians who completed the survey, 114 participated in the screening. Mean head and neck cancer knowledge scores were 26 out of 44. Level of education was the only factor that predicted higher head and neck cancer knowledge (b = 0.90; P = .01). Nine (8%) people had positive head and neck cancer screening examination results. All abnormal clinical findings were in current or past smokers (P = .06). Conclusions. There are gaps in American Indian knowledge of head and neck cancer risk factors and symptoms. Community-based head and neck cancer screening in this population is feasible and may be a way to identify early abnormal clinical findings in smokers. PMID:25320895

  16. Topics in Scattering Amplitudes

    NASA Astrophysics Data System (ADS)

    Dennen, Tristan Lucas

    In Part 1, we combine on-shell methods with the six-dimensional helicity formalism of Cheung and O'Connell to construct tree-level and multiloop scattering amplitudes. As a nontrivial multiloop example, we confirm that the recently constructed four-loop four-point amplitude of N=4 super-Yang-Mills theory, including nonplanar contributions, is valid for dimensions less than or equal to six. We demonstrate that the tree-level amplitudes of maximal super-Yang-Mills theory in six dimensions, when stripped of their overall momentum and supermomentum delta functions, are covariant with respect to the six-dimensional dual conformal group. We demonstrate that this property is also present for loop amplitudes. In Part 2, we explore consequences of the recently discovered duality between color and kinematics, which states that kinematic numerators in a diagrammatic expansion of gauge-theory amplitudes can be arranged to satisfy Jacobi-like identities in one-to-one correspondence to the associated color factors. The related squaring relations express gravity amplitudes in terms of gauge-theory ingredients. We then present a Yang-Mills Lagrangian whose diagrams through five points manifestly satisfy the duality between color and kinematics. Finally, we compute the coefficient of the potential three-loop divergence in pure N=4 supergravity and show that it vanishes, contrary to expectations from symmetry arguments.

  17. Preventing head injuries in children

    MedlinePlus

    ... strapped in with the safety harness. Store all firearms and bullets in a locked cabinet. ... of Health and Human Services. Centers for Disease Control and Prevention. Heads up. Facts for physicians about ...

  18. Heater head for stirling engine

    DOEpatents

    Corey, John A.

    1985-07-09

    A monolithic heater head assembly which augments cast fins with ceramic inserts which narrow the flow of combustion gas and obtains high thermal effectiveness with the assembly including an improved flange design which gives greater durability and reduced conduction loss.

  19. Tensile Tests of Round-head, Flat-head, and Brazier-head Rivets

    NASA Technical Reports Server (NTRS)

    Schuette, Evan H; Bartone, Leonard M; Mandel, Merven W

    1944-01-01

    An investigation was conducted to determine the tensile strength of round-head (AN43C), flat-head(AN442), and brazier-head (AN4556) aluminum-alloy rivets because of the scarcity of information on the tensile strength of rivets. The results of the investigation are presented as curves that show the variation of the ratio of the tensile strength of the rivet to the tensile strength of the rivet crank with the ratio of the sheet thickness to the rivet diameter for the different types of rivet.

  20. Indications for ulnar head replacement.

    PubMed

    Berger, Richard A

    2008-08-01

    Implanting an endoprosthesis is a clinically proven means of reestablishing mechanical contact between the distal radius and ulna, thus providing the foundation for stability of the entire forearm. The indications for, contraindications to, and outcomes of ulnar head replacement are discussed, together with the underlying mechanics, pathomechanics of ulnar head excision, the theoretical basis for implant arthroplasty, and the designs that have been employed. PMID:18836608

  1. Cutting head for ultrasonic lithotripsy

    NASA Technical Reports Server (NTRS)

    Anguluo, E. D.; Goodfriend, R. (Inventor)

    1985-01-01

    A cutting head for attachment to the end of the wire probe of an ultrasonic kidney stone disintegration instrument is described. The cutting head has a plurality of circumferentially arranged teeth formed at one end thereof to provide a cup shaped receptacle for kidney stones encountered during the disintegration procedure. An integral reduced diameter collar diminishes stress points in the wire and reduce breakage thereof.

  2. Head Pose Estimation Using Multilinear Subspace Analysis for Robot Human Awareness

    NASA Technical Reports Server (NTRS)

    Ivanov, Tonislav; Matthies, Larry; Vasilescu, M. Alex O.

    2009-01-01

    Mobile robots, operating in unconstrained indoor and outdoor environments, would benefit in many ways from perception of the human awareness around them. Knowledge of people's head pose and gaze directions would enable the robot to deduce which people are aware of the its presence, and to predict future motions of the people for better path planning. To make such inferences, requires estimating head pose on facial images that are combination of multiple varying factors, such as identity, appearance, head pose, and illumination. By applying multilinear algebra, the algebra of higher-order tensors, we can separate these factors and estimate head pose regardless of subject's identity or image conditions. Furthermore, we can automatically handle uncertainty in the size of the face and its location. We demonstrate a pipeline of on-the-move detection of pedestrians with a robot stereo vision system, segmentation of the head, and head pose estimation in cluttered urban street scenes.

  3. Limitations in scatter propagation

    NASA Astrophysics Data System (ADS)

    Lampert, E. W.

    1982-04-01

    A short description of the main scatter propagation mechanisms is presented; troposcatter, meteor burst communication and chaff scatter. For these propagation modes, in particular for troposcatter, the important specific limitations discussed are: link budget and resulting hardware consequences, diversity, mobility, information transfer and intermodulation and intersymbol interference, frequency range and future extension in frequency range for troposcatter, and compatibility with other services (EMC).

  4. Compton scattering overview

    SciTech Connect

    Hartemann, F V

    2008-12-01

    An overview of linear and nonlinear Compton scattering is presented, along with a comparison with Thomson scattering. Two distinct processes play important roles in the nonlinear regime: multi-photon interactions, leading to the generation of harmonics, and radiation pressure, yielding a downshift of the radiated spectral features. These mechanisms, their influence on the source brightness, and different modeling strategies are also briefly discussed.

  5. Diffractive hard scattering

    SciTech Connect

    Berger, E.L.; Collins, J.C.; Soper, D.E.; Sterman, G.

    1986-03-01

    I discuss events in high energy hadron collisions that contain a hard scattering, in the sense that very heavy quarks or high P/sub T/ jets are produced, yet are diffractive, in the sense that one of the incident hadrons is scattered with only a small energy loss. 8 refs.

  6. Electron scattering intensities and Patterson functions of Skyrmions

    NASA Astrophysics Data System (ADS)

    Karliner, M.; King, C.; Manton, N. S.

    2016-06-01

    The scattering of electrons off nuclei is one of the best methods of probing nuclear structure. In this paper we focus on electron scattering off nuclei with spin and isospin zero within the Skyrme model. We consider two distinct methods and simplify our calculations by use of the Born approximation. The first method is to calculate the form factor of the spherically averaged Skyrmion charge density; the second uses the Patterson function to calculate the scattering intensity off randomly oriented Skyrmions, and spherically averages at the end. We compare our findings with experimental scattering data. We also find approximate analytical formulae for the first zero and first stationary point of a form factor.

  7. SCAP. Point Kernel Single or Albedo Scatter

    SciTech Connect

    Disney, R.K.; Bevan, S.E.

    1982-08-05

    SCAP solves for radiation transport in complex geometries using the single or albedo-scatter point kernel method. The program is designed to calculate the neutron or gamma-ray radiation level at detector points located within or outside a complex radiation scatter source geometry or a user-specified discrete scattering volume. The geometry is described by zones bounded by intersecting quadratic surfaces with an arbitrary maximum number of boundary surfaces per zone. The anisotropic point sources are described as point-wise energy dependent distributions of polar angles on a meridian; isotropic point sources may be specified also. The attenuation function for gamma rays is an exponential function on the primary source leg and the scatter leg with a buildup factor approximation to account for multiple scatter on the scatter leg. The neutron attenuation function is an exponential function using neutron removal cross sections on the primary source leg and scatter leg. Line or volumetric sources can be represented as distributions of isotropic point sources, with uncollided line-of-sight attenuation and buildup calculated between each source point and the detector point.

  8. Ghost Head Nebula

    NASA Technical Reports Server (NTRS)

    1999-01-01

    Looking like a colorful holiday card, a new image from NASA's Hubble Space Telescope reveals a vibrant green and red nebula far from Earth.

    The image of NGC 2080, taken by Hubble's Wide Field and Planetary Camera 2, designed and built by NASA's Jet Propulsion Laboratory, Pasadena, Calif., is available online at http://www.jpl.nasa.gov/images/wfpc . Images like this help astronomers investigate star formation in nebulas.

    NGC 2080, nicknamed 'The Ghost Head Nebula,' is one of a chain of star-forming regions lying south of the 30 Doradus nebula in the Large Magellanic Cloud. 30 Doradus is the largest star-forming complex in the local group of galaxies. This 'enhanced color' picture is composed of three narrow-band-filter images obtained by Hubble on March 28, 2000.

    The red and blue light come from regions of hydrogen gas heated by nearby stars. The green light on the left comes from glowing oxygen. The energy to illuminate the green light is supplied by a powerful stellar wind, a stream of high-speed particles coming from a massive star just outside the image. The central white region is a combination of all three emissions and indicates a core of hot, massive stars in this star-formation region. Intense emission from these stars has carved a bowl-shaped cavity in surrounding gas.

    In the white region, the two bright areas (the 'eyes of the ghost') - named A1 (left) and A2 (right) -- are very hot, glowing 'blobs' of hydrogen and oxygen. The bubble in A1 is produced by the hot, intense radiation and powerful stellar wind from one massive star. A2 contains more dust and several hidden, massive stars. The massive stars in A1 and A2 must have formed within the last 10,000 years, since their natal gas shrouds are not yet disrupted by the powerful radiation of the newborn stars.

    The Space Telescope Science Institute is operated by the Association of Universities for Research in Astronomy, Inc., for NASA, under contract with the Goddard Space Flight Center

  9. Toward improved photon-atom scattering predictions

    NASA Astrophysics Data System (ADS)

    Kissel, Lynn

    1995-05-01

    Photon-atom scattering is important in a variety of applications, but scattering from a composite system depends on the accurate characterization of the scattering from an isolated atom or ion. We have been examining the validity of simpler approximations of elastic scattering in the light of second-order S-matrix theory. Partitioning the many-body amplitude into Rayleigh and Delbrück components, processes beyond photoionization contribute. Subtracted cross sections for bound-bound atomic transitions and bound pair annihilation are required in anomalous scattering factors for: (1) convergence of the dispersion integral; (2) agreement with predictions of the more sophisticated S-matrix approach; (3) satisfying the Thomas-Reiche-Kuhn sum rule. New accurate tabulations of anomalous scattering factors have been prepared for all Z, for energies 0-10 000 keV, within the independent particle approximation (IPA) using a Dirac-Slater model of the atom. Separately, experimental atomic photoabsorption threshold information has been used to modify these IPA predictions for improved comparison with experiment.

  10. Toward improved photon-atom scattering predictions

    NASA Astrophysics Data System (ADS)

    Kissel, Lynn

    1994-10-01

    Photon-atom scattering is important in a variety of applications, but scattering from a composite system depends on the accurate characterization of the scattering from an isolated atom or ion. We have been examining the validity of simpler approximations of elastic scattering in the light of second-order S-matrix theory. Partitioning the many-body amplitude into Rayleigh and Delbrueck components, processes beyond photoionization contribute. Subtracted cross sections for bound-bound atomic transitions, bound pair annihilation, and bound pair production are required in anomalous scattering factors for: (1) convergence of the dispersion integral; (2) agreement with predictions of the more sophisticated S-matrix approach; (3) satisfying the Thomas-Reiche-Kuhn sum rule. New accurate tabulations of anomalous scattering factors have been prepared for all Z, for energies 0-10,000 keV, within the independent particle approximation (IPA) using a Dirac-Slater model of the atom. Separately, experimental atomic photoabsorption threshold information has been used to modify these IPA predictions for improved comparison with experiment.

  11. Light scattering study of rheumatoid arthritis

    SciTech Connect

    Beuthan, J; Netz, U; Minet, O; Mueller, G; Scheel, A; Henniger, J

    2002-11-30

    The distribution of light scattered by finger joints is studied in the near-IR region. It is shown that variations in the optical parameters of the tissue (scattering coefficient {mu}{sub s}, absorption coefficient {mu}{sub a}, and anisotropy factor g) depend on the presence of the rheumatoid arthritis (RA). At the first stage, the distribution of scattered light was measured in diaphanoscopic experiments. The convolution of a Gaussian error function with the scattering phase function proved to be a good approximation of the data obtained. Then, a new method was developed for the reconstruction of distribution of optical parameters in the finger cross section. Model tests of the quality of this reconstruction method show good results. (laser biology and medicine)

  12. Tumefactive fibro-inflammatory lesions of the head and neck.

    PubMed

    Wold, L E; Weiland, L H

    1983-07-01

    Seven patients had tumefactive inflammatory fibrous lesions of the head similar in histologic appearance to Riedel's thyroiditis, sclerosing mediastinitis, and retroperitoneal fibrosis. Five patients were females, and the mean age at presentation was 48 years. Four patients presented clinically with a mass. Histologically, these lesions were characterized by an admixture of mature fibrous tissue and an inflammatory infiltrate of lymphocytes and scattered polymorphonuclear leukocytes. Initially, all patients had been treated surgically. Two patients received radiation therapy when recurrent disease could not be controlled surgically. Five of the six patients on whom follow-up information was available were alive at follow-up that ranged from 14 to 49 months (mean 29). These lesions are distinct histologically from desmoid tumors, fibromatoses, and nodular fasciitis. The spectrum of fibrosclerosing lesions (Riedel's thyroiditis, idiopathic mediastinal fibrosis, retroperitoneal fibrosis, and sclerosing cholangitis) probably includes this group of tumefactive inflammatory fibrous lesions of the head. PMID:6614311

  13. 29 CFR 1917.93 - Head protection.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 29 Labor 7 2010-07-01 2010-07-01 false Head protection. 1917.93 Section 1917.93 Labor Regulations...) MARINE TERMINALS Personal Protection § 1917.93 Head protection. (a) The employer shall ensure that each... the head from falling objects. (b)(1) The employer must ensure that head protection complies with...

  14. 29 CFR 1917.93 - Head protection.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 29 Labor 7 2014-07-01 2014-07-01 false Head protection. 1917.93 Section 1917.93 Labor Regulations...) MARINE TERMINALS Personal Protection § 1917.93 Head protection. (a) The employer shall ensure that each... the head from falling objects. (b)(1) The employer must ensure that head protection complies with...

  15. 29 CFR 1926.100 - Head protection.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 29 Labor 8 2010-07-01 2010-07-01 false Head protection. 1926.100 Section 1926.100 Labor... § 1926.100 Head protection. (a) Employees working in areas where there is a possible danger of head... Institute, Z89.1-1969, Safety Requirements for Industrial Head Protection. (c) Helmets for the...

  16. 29 CFR 1917.93 - Head protection.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 29 Labor 7 2012-07-01 2012-07-01 false Head protection. 1917.93 Section 1917.93 Labor Regulations...) MARINE TERMINALS Personal Protection § 1917.93 Head protection. (a) The employer shall ensure that each... the head from falling objects. (b)(1) The employer must ensure that head protection complies with...

  17. 29 CFR 1917.93 - Head protection.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 29 Labor 7 2011-07-01 2011-07-01 false Head protection. 1917.93 Section 1917.93 Labor Regulations...) MARINE TERMINALS Personal Protection § 1917.93 Head protection. (a) The employer shall ensure that each... the head from falling objects. (b)(1) The employer must ensure that head protection complies with...

  18. 29 CFR 1917.93 - Head protection.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 29 Labor 7 2013-07-01 2013-07-01 false Head protection. 1917.93 Section 1917.93 Labor Regulations...) MARINE TERMINALS Personal Protection § 1917.93 Head protection. (a) The employer shall ensure that each... the head from falling objects. (b)(1) The employer must ensure that head protection complies with...

  19. Communicating printed headings to the ear.

    PubMed

    Lorch, Robert F; Chen, Hung-Tao; Jawahir, Aqeel A; Lemarié, Julie

    2016-05-01

    Two experiments compared three methods of translating printed headings into an auditory format. In both experiments, college students listened to a text with instructions to stop the recording whenever they heard a heading and type the hierarchical level and exact wording of the heading. Listeners were poor at identifying headings and their levels if the headings were not distinguished from the rest of the text. However, listeners were very good at identifying headings if any method of signalling was used to distinguish headings and communicate their hierarchical level. The methods included: (1) tones preceding headings, (2) changes of speaker to indicate headings or (3) verbal labels preceding headings. Although all three signalling methods improved identification of a heading's hierarchical level, the labelling method was the most effective means of communicating hierarchical level. Thus, the study identifies a simple method of effectively communicating headings in spoken text. Practitioner Summary: The study attempted to identify effective ways of communicating heading information in spoken text. College students listened to texts in order to detect headings and record their wording and hierarchical level. Performance was excellent when headings were preceded by verbal phrases that signalled the upcoming headings and their levels. PMID:27267653

  20. Dense Plasma X-ray Scattering: Methods and Applications

    SciTech Connect

    Glenzer, S H; Lee, H J; Davis, P; Doppner, T; Falcone, R W; Fortmann, C; Hammel, B A; Kritcher, A L; Landen, O L; Lee, R W; Munro, D H; Redmer, R; Weber, S

    2009-08-19

    We have developed accurate x-ray scattering techniques to measure the physical properties of dense plasmas. Temperature and density are inferred from inelastic x-ray scattering data whose interpretation is model-independent for low to moderately coupled systems. Specifically, the spectral shape of the non-collective Compton scattering spectrum directly reflects the electron velocity distribution. In partially Fermi degenerate systems that have been investigated experimentally in laser shock-compressed beryllium, the Compton scattering spectrum provides the Fermi energy and hence the electron density. We show that forward scattering spectra that observe collective plasmon oscillations yield densities in agreement with Compton scattering. In addition, electron temperatures inferred from the dispersion of the plasmon feature are consistent with the ion temperature sensitive elastic scattering feature. Hence, theoretical models of the static ion-ion structure factor and consequently the equation of state of dense matter can be directly tested.

  1. Calculates Thermal Neutron Scattering Kernel.

    Energy Science and Technology Software Center (ESTSC)

    1989-11-10

    Version 00 THRUSH computes the thermal neutron scattering kernel by the phonon expansion method for both coherent and incoherent scattering processes. The calculation of the coherent part is suitable only for calculating the scattering kernel for heavy water.

  2. Pattern of head and neck cancer in Yemen.

    PubMed

    Abdul-Hamid, G; Saeed, N M; Al-Kahiry, W; Shukry, S

    2010-01-01

    Head and neck cancer constitutes one of the commonest malignancies in Yemen. There may be a role for the use of Shamma and Zarda and Khat for the increase of HNC in Yemen. This study was conducted retrospectively with an overall aim to describe the pattern of head and neck cancers among Yemeni patients attending the Oncology Department of Al-Gamhouria Teaching Hospital, Aden, for the period from Jan. 2001 to Dec. 2004. The study included 183 patients with head and neck cancers (Lymphoma and thyroid were excluded), 134 were males (73.2%) and 49 were females (26.8%) , with male to female ratio of 2.7:1. The mean age was 51.3 +/- 14.9 years (range: 3 - 82 years). Statistically, there is significant difference between the mean age of male (49.5 +/- 15.1 years) and female (45.4 +/- 16.3 years) patients with head and neck cancers [t= 2.1, p: 0.03]. The common types of head and neck cancers in this study are cancers of the oral cavity (31.7%), followed by pharyngeal (22.9%) and laryngeal (19.1%). In relation to sex, there is a significant statistical relationship between certain head and neck cancers and sex (p: 0.0000). In males, the common cancers are oral cavity cancers (22.7%), laryngeal (22.1%) and pharyngeal cancers (20.8%). The common histopathological type of head and neck cancers in this study is the well differentiated squamous cell carcinoma (70.5%). This study concluded that head and neck cancers are among the common health problems affecting Yemeni patients and recommended further wide national studies to determine the real incidence and the risk factors associated with such cancer. PMID:20164005

  3. The perception of heading during eye movements

    NASA Technical Reports Server (NTRS)

    Royden, Constance S.; Banks, Martin S.; Crowell, James A.

    1992-01-01

    Warren and Hannon (1988, 1990), while studying the perception of heading during eye movements, concluded that people do not require extraretinal information to judge heading with eye/head movements present. Here, heading judgments are examined at higher, more typical eye movement velocities than the extremely slow tracking eye movements used by Warren and Hannon. It is found that people require extraretinal information about eye position to perceive heading accurately under many viewing conditions.

  4. Severe Traumatic Head Injury Affects Systemic Cytokine Expression

    PubMed Central

    LaPar, Damien J; Rosenberger, Laura H; Walters, Dustin M; Hedrick, Traci L; Swenson, Brian R; Young, Jeffrey S; Dossett, Lesly A; May, Addison K; Sawyer, Robert G

    2012-01-01

    Background The neuroimmunologic effect of traumatic head injury remains ill-defined. This study aimed to characterize systemic cytokine profiles among traumatically injured patients to assess the effect of traumatic head injury on the systemic inflammatory response. Study Design Over five years, 1,022 patients were evaluated from a multi-institutional trauma immunomodulatory database (TIMD). Patients were stratified by presence of severe head injury (SHI, Head ISS ≥ 4, n=335) versus non-severe head injury (NHI, Head ISS ≤ 3, n=687). Systemic cytokine expression was quantified by ELISA within 72 hours of admission. Patient factors, outcomes, and cytokine profiles were compared by univariate analyses. Results SHI patients were more severely injured with higher mortality despite similar ICU infection and ventilator associated pneumonia (VAP) rates. Expression of early pro-inflammatory cytokines, IL-6 (p<0.001) and tumor necrosis factor (TNF)-α (p=0.02), were higher among NHI patients, while expression of immunomodulatory cytokines, interferon-γ (p=0.01) and IL-12 (p=0.003), was higher in SHI patients. High TNF-α levels in NHI patients were associated with mortality (p=0.01), increased mechanical ventilation (p=0.02), and development of VAP (p=0.01). Alternatively, among SHI patients, high IL-2 levels were associated with survival, decreased mechanical ventilation, and absence of VAP. Conclusions The presence of severe traumatic head injury significantly alters systemic cytokine expression and exerts an immunomodulatory effect. Early recognition of these profiles may allow for targeted intervention to reduce patient morbidity and mortality. PMID:22342787

  5. Prediction of Chronic Subdural Hematoma in Minor Head Trauma Patients

    PubMed Central

    Han, Sang-Beom; Song, Shi-Hun; Youm, Jin-Young; Koh, Hyeon-Song; Kim, Seon-Hwan; Kwon, Hyon-Jo

    2014-01-01

    Objective Chronic subdural hematoma (CSDH) is relatively common in neurosurgical field. However not all patients develop CSDH after minor head trauma. In this study, we evaluate the risk factors of post-traumatic CSDH. Methods Two-hundred and seventy-seven patients were enrolled and analyzed in this study from January 2012 to December 2013. Of those, 20 participants had minor head trauma developed CSDH afterward. We also included 257 patients with minor head trauma who did not develop CSDH during the same follow-up period as the control group. We investigated the risk factors related to the development of CSDH after minor head trauma. Results Old age (p=0.014), preexisting diabetes mellitus (p=0.010), hypertension (p=0.026), history of cerebral infarction (p=0.035), antiplatelet agents (p=0.000), acute subdural hematoma in the convexity (p=0.000), encephalomalacia (p=0.029), and long distance between skull and brain parenchyma (p=0.000) were significantly correlated with the development of CSDH after trauma. Multivariate analysis revealed that only the maximum distance between the skull and the cerebral parenchyma was the independent risk factor for the occurrence of CSDH (hazard ratio 2.55, p=0.000). Conclusion We should consider the possibility of developing CSDH in the post-traumatic patients with the identified risk factors. PMID:27169043

  6. Parents' Role in the Early Head Start Children's Language Development

    ERIC Educational Resources Information Center

    Griswold, Cecelia Smalls

    2014-01-01

    The development of language during a child's early years has been linked to parental involvement. While Early Head Start (EHS) researchers have theorized that parental involvement is an important factor in language development, there has been little research on how parents view their roles in the language development process. The purpose of this…

  7. Maternal Role Competence: Promoting Family Resilience in Head Start Programs

    ERIC Educational Resources Information Center

    Grossman, Judy

    2005-01-01

    This article describes one component of a comprehensive model of family-centered preventive mental health services that were delivered as part of a University-Head Start Partnership grant. Personal Best, a carefully designed role competence curriculum, was implemented through a group intervention to examine the personal and contextual factors that…

  8. Kernel Integration Code System--Multigroup Gamma-Ray Scattering.

    Energy Science and Technology Software Center (ESTSC)

    1988-02-15

    GGG (G3) is the generic designation for a series of computer programs that enable the user to estimate gamma-ray scattering from a point source to a series of point detectors. Program output includes detector response due to each source energy, as well as a grouping by scattered energy in addition to a simple, unscattered beam result. Although G3 is basically a single-scatter program, it also includes a correction for multiple scattering by applying a buildupmore » factor for the path segment between the point of scatter and the detector point. Results are recorded with and without the buildup factor. Surfaces, defined by quadratic equations, are used to provide for a full three-dimensional description of the physical geometry. G3 evaluates scattering effects in those situations where more exact techniques are not economical. G3 was revised by Bettis and the name was changed to indicate that it was no longer identical to the G3 program. The name S3 was chosen since the scattering calculation has three steps: calculation of the flux arriving at the scatterer from the point source, calculation of the differential scattering cross section, and calculation of the scattered flux arriving at the detector.« less

  9. Rayleigh Scattering Diagnostics Workshop

    NASA Technical Reports Server (NTRS)

    Seasholtz, Richard (Compiler)

    1996-01-01

    The Rayleigh Scattering Diagnostics Workshop was held July 25-26, 1995 at the NASA Lewis Research Center in Cleveland, Ohio. The purpose of the workshop was to foster timely exchange of information and expertise acquired by researchers and users of laser based Rayleigh scattering diagnostics for aerospace flow facilities and other applications. This Conference Publication includes the 12 technical presentations and transcriptions of the two panel discussions. The first panel was made up of 'users' of optical diagnostics, mainly in aerospace test facilities, and its purpose was to assess areas of potential applications of Rayleigh scattering diagnostics. The second panel was made up of active researchers in Rayleigh scattering diagnostics, and its purpose was to discuss the direction of future work.

  10. Intra-beam scattering

    NASA Astrophysics Data System (ADS)

    Piwinski, A.

    Intra-beam scattering is analysed and the rise times or damping times of the beam dimensions are derived. The theoretical results are compared with experimental values obtained on the CERN AA and SPS machines.

  11. Electron scattering from pyrimidine

    NASA Astrophysics Data System (ADS)

    Colmenares, Rafael; Fuss, Martina C.; Oller, Juan C.; Muñoz, Antonio; Blanco, Francisco; Almeida, Diogo; Limão-Vieira, Paulo; García, Gustavo

    2014-04-01

    Electron scattering from pyrimidine (C4H4N2) was investigated over a wide range of energies. Following different experimental and theoretical approaches, total, elastic and ionization cross sections as well as electron energy loss distributions were obtained.

  12. Cosmic Ray Scattering Radiography

    NASA Astrophysics Data System (ADS)

    Morris, C. L.

    2015-12-01

    Cosmic ray muons are ubiquitous, are highly penetrating, and can be used to measure material densities by either measuring the stopping rate or by measuring the scattering of transmitted muons. The Los Alamos team has studied scattering radiography for a number of applications. Some results will be shown of scattering imaging for a range of practical applications, and estimates will be made of the utility of scattering radiography for nondestructive assessments of large structures and for geological surveying. Results of imaging the core of the Toshiba Nuclear Critical Assembly (NCA) Reactor in Kawasaki, Japan and simulations of imaging the damaged cores of the Fukushima nuclear reactors will be presented. Below is an image made using muons of a core configuration for the NCA reactor.

  13. Mayo Clinic Experience with Unfavorable Results After Free Tissue Transfer to Head and Neck.

    PubMed

    Nagel, Thomas H; Hayden, Richard E

    2016-10-01

    Free tissue transfer to the head and neck in the modern era has a high success rate. To maximize success with reconstructive surgery in the head and neck region, it helps to understand those factors that present unique challenges. These factors include contamination by the upper aerodigestive tract, tissue mobility, and a high percentage of patients receiving radiotherapy for oncologic treatment. This article reviews the authors' experience in the head and neck, specifically how addressing these factors can best lead to successful functional and aesthetic outcomes. The authors share surgical techniques and lessons learned from their successes and failures. PMID:27601391

  14. Positron-rubidium scattering

    NASA Technical Reports Server (NTRS)

    Mceachran, R. P.; Horbatsch, M.; Stauffer, A. D.

    1990-01-01

    A 5-state close-coupling calculation (5s-5p-4d-6s-6p) was carried out for positron-Rb scattering in the energy range 3.7 to 28.0 eV. In contrast to the results of similar close-coupling calculations for positron-Na and positron-K scattering the (effective) total integrated cross section has an energy dependence which is contrary to recent experimental measurements.

  15. [Bobble-head doll syndrome].

    PubMed

    Roubergue, A; Beauvais, P; Richardet, J M

    1985-05-01

    A new case of Bobble-head doll syndrome with aqueductal stenosis is presented in a 14 year-old boy. Ventriculocisternostomy performed 8 years after the onset of the abnormal movement resulted in moderate reduction of the head bobbling. Twenty-two cases were found in a review of the literature. In all cases there was a chronic slowly progressive hydrocephalus with usually a cyst of the third ventricle; aqueductal stenosis was less frequent. When recorded, psychomotor development was impaired. Treatment is neurosurgical. Pathogenesis remains unknown. PMID:4074089

  16. Rotary head type reproducing apparatus

    DOEpatents

    Takayama, Nobutoshi; Edakubo, Hiroo; Kozuki, Susumu; Takei, Masahiro; Nagasawa, Kenichi

    1986-01-01

    In an apparatus of the kind arranged to reproduce, with a plurality of rotary heads, an information signal from a record bearing medium having many recording tracks which are parallel to each other with the information signal recorded therein and with a plurality of different pilot signals of different frequencies also recorded one by one, one in each of the recording tracks, a plurality of different reference signals of different frequencies are simultaneously generated. A tracking error is detected by using the different reference signals together with the pilot signals which are included in signals reproduced from the plurality of rotary heads.

  17. Variation in natural head position and establishing corrected head position.

    PubMed

    Barbera, A L; Sampson, W J; Townsend, G C

    2014-06-01

    Corrected head position (CHP) has been simulated by using the Frankfurt horizontal (FH) for over 100 years but FH varies between individuals. Because CHP is biologically relevant for orthodontic diagnosis and treatment planning, orthognathic surgical planning, and art, this study examined relationships between head position and selected cephalometric planes. Natural head position cephalograms of Aboriginal Australians and two contemporary samples from private orthodontic practices were analysed. Each sample comprised 40 individuals (20 males and 20 females). The Aboriginal Australian sample comprised longitudinal data (T1 early adolescent, T2 late adolescent, and T3 adult), enabling examination of natural head position (NHP) reproducibility over a period of approximately 8 years. Results of reproducibility differences revealed an absolute mean=2.9°, range=-7.9° to 8.2°, and standard deviation=3.6°. Stable basicranial line (SBL), neutral horizontal axis (NHA), FH, palatal plane (P plane), and Krogman-Walker plane (KW plane) demonstrated near parallelism and their mean angulations from the true horizontal (HOR) ranged between -4.6° and 2.4°. While NHP is not consistently reproducible at the individual level, the combined use of multiple planes such as SBL, P plane, and KW plane enables a more consistent CHP to be achieved. PMID:24785580

  18. Head kinematics during shaking associated with abusive head trauma.

    PubMed

    Lintern, T O; Puhulwelle Gamage, N T; Bloomfield, F H; Kelly, P; Finch, M C; Taberner, A J; Nash, M P; Nielsen, P M F

    2015-09-18

    Abusive head trauma (AHT) is a potentially fatal result of child abuse but the mechanisms of injury are controversial. To address the hypothesis that shaking alone is sufficient to elicit the injuries observed, effective computational and experimental models are necessary. This paper investigates the use of a coupled rigid-body computational modelling framework to reproduce in vivo shaking kinematics in AHT. A sagittal plane OpenSim computational model of a lamb was developed and used to interpret biomechanical data from in vivo shaking experiments. The acceleration of the head during shaking was used to provide in vivo validation of the associated computational model. Results of this study demonstrated that peak accelerations occurred when the head impacted the torso and produced acceleration magnitudes exceeding 200ms(-)(2). The computational model demonstrated good agreement with the experimental measurements and was shown to be able to reproduce the high accelerations that occur during impact. The biomechanical results obtained with the computational model demonstrate the utility of using a coupled rigid-body modelling framework to describe infant head kinematics in AHT. PMID:26256822

  19. Giant scattering cones in obscured quasars

    NASA Astrophysics Data System (ADS)

    Obied, Georges; Zakamska, Nadia L.; Wylezalek, Dominika; Liu, Guilin

    2016-03-01

    We analyse Hubble Space Telescope observations of scattering regions in 20 luminous obscured quasars at 0.24 < z < 0.65 (11 new observations and nine archival ones) observed at rest frame ˜3000 Å. We find spectacular 5-10 kpc-scale scattering regions in almost all cases. The median scattering efficiency at this wavelength (the ratio of observed to estimated intrinsic flux) is 2.3, and 73 per cent of the observed flux at this wavelength is due to scattered light, which if unaccounted for may strongly bias estimates of quasar hosts' star formation rates. Modelling these regions as illuminated dusty cones, we estimate the radial density distributions of the interstellar medium as well as the geometric properties of circumnuclear quasar obscuration - inclinations and covering factors. Small derived opening angles (median half-angle and standard deviation 27° ± 9°) are inconsistent with a 1:1 type 1/type 2 ratio. We suggest that quasar obscuration is patchy and that the observer has an ˜40 per cent chance of seeing a type 1 source even through the obscuration. We estimate median density profile of the scattering medium to be nH = 0.04-0.5 (1 kpc/r)2 cm-3, depending on the method. Quasars in our sample likely exhibit galaxy-wide winds, but if these consist of optically thick clouds then only a small fraction of the wind mass ( ≲ 10 per cent) contributes to scattering.

  20. Anomalous and resonance small angle scattering: Revision

    SciTech Connect

    Epperson, J.E.; Thiyagarajan, P.

    1987-11-01

    Significant changes in the small angle scattered intensity can be induced by making measurements with radiation close to an absorption edge of an appropriate atomic species contained in the sample. These changes can be related quantitatively to the real and imaginary anomalous dispersion terms for the scattering factor (x-rays) or scattering length (neutrons). The physics inherent in these anomalous dispersion terms is first discussed before considering how they enter the relevant scattering theory. Two major areas of anomalous scattering research have emerged; macromolecules in solution and unmixing of metallic alloys. Research in each area is reviewed, illustrating both the feasibility and potential of these techniques. All the experimental results reported to date have been obtained with x-rays. However, it is pointed out that the formalism is the same for the analogue experiment with neutrons, and a number of suitable isotopes exist which exhibit resonance in an accessible range of energy. Potential applications of resonance small angle neutron scatterings are discussed. 54 refs., 8 figs., 1 tab.