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Copyright of Der Orthopäde is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

For characterizing the homogeneity of a copper standard for optical emission spectrometry, the results of spark source mass spectrographic (SSMS) milliprobing have been treated by diverse chemometric methods. The proposed strategy includes visualization of the data, global homogeneity testing for each element, testing the anisotropy of elemental distributions, search for correlation between elements, and statements on the homogeneity with respect to other analytical procedures. The copper standard was proved to be non-homogeneous for SSMS but homogeneous for techniques of optical emission spectroscopy having larger sampling volumes. [ABSTRACT FROM AUTHOR]

Copyright of Fresenius' Zeitschrift für Analytische Chemie is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The present paper demonstrates that neutron-photon pairs from radiative capture of stopped pions on chemically bound protons can be used to measure the range of negative pions within phantoms or a patient. Experimental results are given for a polyethylene and a water target of realistic size as well as for a Rando phantom. Monte-Carlo calculations were carried out in order to study the influence of various sizes of treatment volumes, detector geometries and neutron scattering within the targets upon the accuracy of the pion range determination. The results reveal clearly that a pion range monitor for the control of therapy plans and for actual patient irradiations can be designed according to the proposed principle. The absorbed dose required for a measurement is of the order of 0.1 Gy for a single pion beam if one aims at an accuracy of range determination of a few millimeters. [ABSTRACT FROM AUTHOR]

A technique suitable for mapping π stopping density distributions in patients or phantoms is described. As a position sensitive detector a multiwire proportional chamber with a slit or a hole collimator in front was applied. Results using a water and a Rando phantom are presented for various momenta and momentum band widths of the π beam. To our knowledge the two-dimensional visualization of a π stopping density distribution was realized for the first time. [ABSTRACT FROM AUTHOR]

Changes in the width of the CSF space throughout life were studied in CT scans of 170 healthy individuals. The internal and external CSF spaces were evaluated using parameters which can also be employed in routine clinical studies. Tables of normal values for the CSF spaces at various ages are presented. [ABSTRACT FROM AUTHOR]

This paper describes an applicative order graph reducer which under interactive control performs high-level program transformations that are governed by the reduction semantics of a full-fledged untyped γ-calculus. To do so with competitive speed, high-level functional programs are by a pre-processor reversibly converted into graph representations of γ-terms. Its subterms are closed by the abstraction of relatively free variables only to the extent absolutely necessary to avoid the complexity of full β-reductions at run-time. Processing these γ-terms is based on high-level interpretation which exploits the simplicity and efficiency of naive graph pointer substitutions when reducing function calls. Partially or completely reduced graphs are by a post-processor re-converted into high-level programs. Full β-reductions are only employed by the pre- and post-processor to maintain correct binding levels when abstracting free variables from γ-terms and when undoing these abstractions or reducing partial applications left over as closures, respectively. [ABSTRACT FROM AUTHOR]

Copyright of Zeitschrift für Physik is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Zeitschrift für Physik is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Zeitschrift für Physik is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Zeitschrift für Physik is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The three-particle reaction p+d→p+p+n has been investigated at a deuteron bombarding energy of 52.0 MeV. Single counter experiments as well as coincidence measurements have been carried out. The laboratory angular distribution of the break-up reaction and the total break-up cross-section have been determined by means of the single counter experiments. The angular distribution for final-state interacting neutron-proton pairs was obtained by means of coincidence measurements. The coincidence experiments provide a strong evidence for very different shapes of the angular distributions for neutron-proton singlet and triplet final-state interaction. [ABSTRACT FROM AUTHOR]

The elastic deuteron-deuteron scattering and the reactions d(d,p)t and d(d,He) n have been investigated at an incident deuteron energy of 51.5 MeV. Time-of-flight technique was used for the particle identification. The observed angular distributions for the ( d, p) and ( d, n) reaction are identical within the accuracy of the experimental data. The experimental results for the reaction d(d, p)t are compared with a theoretical prediction based on the application of a generalized separable potential model to the four nucleon systems. Information on the single deuteron break-up reaction d+d→d+p+n and on the double deuteron break-up reaction d+d→p+p+n+n is contained in the observed continuous proton and deuteron spectra. The double break-up seems to be contribute only with a rather small amount to the whole break-up cross section. [ABSTRACT FROM AUTHOR]

The polarization of neutrons produced in the reactionC( d, n)N was measured. Deuterons from the Karlsruhe isochronous cyclotron were used to induce this reaction at 51,5 MeV laboratory energy. The degree of polarization was determined by using the special features of Mott-Schwinger scattering. With an uranium scatterer analysing efficiencies of up to 0.92 can be obtained at very small angles (0.23°). The analysing efficiency can be calculated if the differential cross section at 0° and the total cross section is known. These quantities were experimentally determined. The differential cross section for 49.4 MeV neutrons, scattered by uranium, was measured between 0.88° and 2.10°. By an extrapolation the value 43.4±2.6 b/sr was found for the nuclear differential cross section at zero degree. A total cross section of σ=4.80±0.22 b was obtained. The neutron polarization was measured at a reaction angle of 24.5° and the result is P=−0.45±0.07. This value is fairly above the semiclassical 1/3 limit and can be only explained, if spin orbit forces are taken into account. For ( d, n) reactions this is the first neutron-polarization measurement above an energy of 20 MeV. [ABSTRACT FROM AUTHOR]

The external beam of 51.5 MeV deuterons from the Karlsruhe isochronous cyclotron was used to investigate the three particle reactions p(d,pp)n and d(d, dp)n. A kinematically complete experiment was performed by detecting the two emitted protons respectively the proton and the deuteron in coincidence. The data for the reaction p (d, pp) n exhibit a pronounced final state interaction between the outgoing neutron and one proton. This final state interaction is mainly due to the n- p singlet interaction and the extracted n- p scattering length is ¦a¦=(19±2.5) fm. In the investigation of the reaction d(d, dp)n the angles were chosen as to observe quasielastic deuteron-proton-scattering predominantly. The data was analysed in terms of the Chew Low Spectator model and we obtained by 'on-energy-shell' extrapolation for the d−p cross section the value (7±2.5) [mb/sr]. This value has to be compared with the cross section for free d−p scattering which was independently measured and the value obtained for the corresponding angle is (16±1) [mb/sr]. [ABSTRACT FROM AUTHOR]

Copyright of Zeitschrift für Physik is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Zeitschrift für Physik is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Zeitschrift für Physik is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

New measurements of the pionic double charge exchange onFe exhibit a pronounced energy dependence of this reaction at low energies in accordance with similar observations on other nuclei. We show that this peculiar energy dependence finds its natural explanation by a resonance in the πNN subsystem with J=0, T=0 and a mass of 2.065 GeV. [ABSTRACT FROM AUTHOR]