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Intracellular and extracellular water volumes in the human body have been computed using a sequence of models starting with a linear first order RC circuit (Cole model) and finishing with the De Lorenzo model. This last model employs a fractional order impedance whose parameters are identified using the frequency characteristics of the impedance module and phase, the latter being not unique. While the Cole model has a two octaves frequency validity range, the De Lorenzo model can be used for three decades. A new linear RC model, valid for a three decades frequency range, is proposed. This circuit can be viewed as an extension of the Cole model for a larger frequency interval, unlike similar models proposed by the same authors.

The large signal operation of the bulk acoustic wave (BAW) resonators is characterized by the amplitude-frequency effect and the intermodulation effect. The measurement of these effects, together with that of the small signal frequency characteristic, are used in this paper for the parameter identification of the nonlinear circuit models developed previously by authors. As the resonator has been connected to the measurement bench by wire bonding, the parasitic elements of this connection have been taken into account, being estimated solving some electrical and magnetic field problems.

The Compton camera, in principle, can improve spatial resolution and efficiency with respect to today's PET and SPECT techniques. The optimization of a Compton camera system in terms of efficiency and resolution is a complex multi-parameter problem. The efficiency depends on various detector parameters (material, thickness, positioning, etc.). The influence of these parameters on the image reconstruction is investigated for a conventional reconstruction technique in order to find optimum detector parameters. The case studies are based on a model for a system consisting of a silicon drift detector (electron detector) and a scintillator detector (photon detector). Effects of secondary and background processes were not included in this model. It was found that high-energy gamma sources (300 keV and more) are preferable over lower-energy sources (e.g., 140 keV) commonly used for SPECT. A Si detector as an electron detector and an angular range between 30[degrees] and 80[degrees] is most useful considering the various physical and experimental constraints. Silicon drift detector (SDD) with integrated front-end electronics offers a very good energy resolution due to its low electronics noise. The intrinsic resolution of both detectors influence the overall resolution considerably. A relatively large pixel size of the SDD considered here reduces the number of readout channels, but also limits the intrinsic resolution. The thickness of the electron detector should be chosen in such a way that its effects on efficiency and spatial resolution are balanced. Interdetector distance of at least 15 cm was found to be appropriate for the detector setup considered in this paper. Index Terms--[sup.113m]In, Compton camera, detector parameters, electronic collimation, emission tomography, silicon drift detector.

Aggressive breast cancer is an invasive form with G3, G4 differentiation degree, the absence of receptors for estrogen and progesterone and the absence or presence of HER2 (+ or 3+) gene. The final diagnosis is established by cumulating the clinical, paraclinical, histopathological and immunohistochemical diagnosis. Material and method: 84 out of 268 aggressive breast cancer cases were presented in the study, which were operated in October 2011-September 2013. The inclusion and exclusion criteria are exposed in the study lot and the treatment schemes. Results: For the study lot (lot A made up of 36 cases, lot B made up of 41 cases, lot C made up of 7 cases) the distribution was presented on age groups, histopathological and immunohistochemical classification, etiologic factors, type of surgery, postoperative staging and complications. Conclusions: The treatment of aggressive breast cancer depends on the level of the aggressiveness of the disease, the biologic status and the age that imposes the order of chemotherapy, radiotherapy, surgical treatment and target therapy. [ABSTRACT FROM AUTHOR]

Aggressive breast cancer is an invasive form with a differentiation degree G3/G4, the absence of estrogen receptor and progesterone and the absence or presence of the gene HER 2(+ or 3+). The immunohistochemical tests have an important role in establishing the diagnosis and the therapy. Material and method: It was shown that the aggressive breast cancers, 97 out of 316 cases were operated in the period October 2011 - February 2014. The criteria of inclusion/ exclusion in the study groups and the treatment schemes were exposed. Results: For the study group (group A=43/ group B=45/ group C=9 cases), the distribution according to the age group and immunohistochemical classification, were shown and, histologically, the type of surgical intervention, postoperative staging, postoperative complications were highlighted. Conclusions: The treatment of the aggressive forms of breast cancer, neoadjuvant and adjuvant can both be set only by IHC tests. [ABSTRACT FROM AUTHOR]

Free vertex operators V(γ,z) are introduced as operators in Hilbert space. They are densely defined for |z|<1. Any radially ordered product of vertex operators is defined on a dense subset as an operator product. ||V(γ,z)Ψ|| is bound by ||exp(cN)Ψ|| for appropriate Ψ, where N is the number operator and c is a positive constant. These results are applied to screened vertex operators. [ABSTRACT FROM AUTHOR]

An explicit form is given of the Borel transform B of g[larger_closed_square]f where g[larger_closed_square]f(z):=g( f(z)) with f Borel summable and g analytic in f(0) and a detailed study of the singularities in B (in the Borel variable) is made. Examples include g(ξ)=1/ξ, log ξ and eξ. The present paper generalizes results of Boenkost et al. [J. Math. Phys. 29, 1118 (1987)]. [ABSTRACT FROM AUTHOR]

A supersymmetric integral theorem that extends results of Parisi, Sourlas, Efetov, Wegner, and others is rigorously proved. In particular, arbitrary generators are allowed in the integrand (instead of canonical ones) and the invariance condition is very much relaxed. The connection with Cauchy’s integral formula is made transparent. In passing, the unitary Lie supergroup is studied by using elementary methods. Applications in the theory of disordered systems are discussed. [ABSTRACT FROM AUTHOR]

Let B1 be the Borel transform of f, f(0)≠0. By means of an integral equation similar to that proposed by ’t Hooft [The Whys of Subnuclear Physics, edited by A. Zichichi (Plenum, New York, 1979)] an explicit representation of the Borel transform B2 of 1/f as a series in convolution powers of B1 and its derivative is given. It is proved that the singularities of B1, B2 on the circle of convergence coincide and have the same strength when approaching these singularities on a path inside their common analyticity domain, but possibly outside the circle of convergence of their power series representation (Borel circle). [ABSTRACT FROM AUTHOR]