Glow curve calculations are presented for a system of interactive traps in which the deep trap population is an order of magnitude greater than that of the active TL traps. It is shown that the glow peak exhibits a first-order type of kinetic behaviour even when recombination does not predominate over retrapping. Under most of the dose ranges it is the recapture by the deep traps which is responsible for this kinetic behaviour. The likely reason for the apparent dominance of first-order kinetics appears to be the interaction between the active TL traps and the deep traps. Another important consequence of interactive kinetics is that the growth of TL intensity with dose becomes supralinear. The interactive nature of the traps thus provides an interpretation not only for the kinetic behaviour of the glow peaks but explains also their supralinearity.Glowkurven werden berechnet fur ein System mit wechselwirkenden Haftstellen, in dem die Konzentration der tiefen Haftstellen um das zehnfache grol3er ist als die der aktiven Haftstellen. Es wird gezeigt, dal3 der auftretende Peak einer Kinetik erster Ordnung entspricht, selbst wenn Rekombination nicht die Wiederhaftung uberwiegt. Fur den grol3ten Teil des Dosisbereichs wird dieses kinetische Verhalten durch Wiederhaftung an tiefen Haftstellen verursacht. Die bestmogliche Ursache fur dieses anscheinende Uberwiegen der Kinetik erster Ordnung scheint die Wechselwirkung zwischen tiefen und aktiven Haftstellen zu sein. Eine andere wichtige Folge der wechselwirkenden Kinetik ist, da8 eine supralineare Beziehung zwischen Dosis und Thermolumineszenzintensitat entsteht. Die wechselwirkende Natur der Haftstellen liefert also nicht nur eine Interpretation fur das kinetische Verhalten der Glowpeaks, sondern erklirt auch ihre Supralinearitat.

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Nowadays, the optimization in digital mammography is one of the most important challenges in diagnostic radiology. The new digital technology has introduced additional elements to be considered in this scenario. A major goal of mammography is related to the detection of structures on the order of micrometers (μm) and the need to distinguish the different types of tissues, with very close density values. The diagnosis in mammography faces the difficulty that the breast tissues and pathological findings have very close linear attenuation coefficients within the energy range used in mammography. The aim of this study was to develop a methodology for optimizing exposure parameters of digital mammography based on a new Figure of Merit: FOM ≡ (IQF)/AGD, considering the image quality and dose. The study was conducted using the digital mammography Senographe DS/GE, and CDMAM and TORMAM phantoms. The characterization of clinical practice, carried out in the mammography system under study, was performed considering different breast thicknesses, the technical parameters of exposure, and processing options of images used by the equipment's automatic exposure system. The results showed a difference between the values of the optimized parameters and those ones chosen by the automatic system of the mammography unit, specifically for small breast. The optimized exposure parameters showed better results than those obtained by the automatic system of the mammography, for the image quality parameters and its impact on detection of breast structures when analyzed by radiologists.

In the present work we propose a generalization of Newton's gravitational theory from the original works of Heaviside and Sciama, that takes into account both approaches, and accomplishes the same result in a simpler way than the standard cosmological approach. The established formulation describes the local gravitational field related to the observables and effectively implements the Mach's principle in a quantitative form that retakes Dirac's large number hypothesis. As a consequence of the equivalence principle and the application of this formulation to the observable universe, we obtain, as an immediate result, a value of Omega = 2. We construct a dynamic model for a galaxy without dark matter, which fits well with recent observational data, in terms of a variable effective inertial mass that reflects the present dynamic state of the universe and that replicates from first principles, the phenomenology proposed in MOND. The remarkable aspect of these results is the connection of the effect dubbed dark matter with the dark energy field, which makes it possible for us to interpret it as longitudinal gravitational waves.Comment: 18 pages, 4 figures. Final version: almost identical to the reference journal; Cent. Eur. J. Phys. 201

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The energy distribution of electrons in a part of the electron beam selected by two apertures situated on the axis was measured using a wienfilter-type energy analyser. These measurements gave brightness values for electrons in specific energy intervals of the distribution which fitted the theory extremely well. The influence of the measuring system on the energy distribution was also demonstrated and it indicated that the discrepancy between experiment and theory observed by Nottingham and Hutson was due to a crude approximation in the electron optics of the theory rather than a large electron reflection effect. The anomalous broadening of the energy distribution (Boersch effect) was found to be independent of the measuring system and had no influence on the brightness. Energy gains were also observed in the broadening process.

The general order kinetics (GOK) expression of thermoluminescence was proposed on the premise that retrapping may neither be neglected altogether nor assumed to have a probability coefficient equal to that of recombination. In the present paper it is shown that the parameters called the kinetic order (b) and the pre-exponential factor (s') vary while the glow curve is being readout and that their effective value for the full glow curve depends on the initial trap occupancy (dose). It is only under restricted conditions that the hand the .r' become independent of trap occupancy. In the case of s', the dimensions also change with the results that the values of this parameter cannot even be compared with each other at different trap occupancies.