405 research outputs found

    Mycosis fungoides bullosa: a case report and review of the literature

    Get PDF
    Introduction: Mycosis fungoides, the most common type of cutaneous T-cell lymphoma, can manifest in a variety of clinical and histological forms. Bulla formation is an uncommon finding in mycosis fungoides and only approximately 20 cases have been reported in the literature. Case presentation: We present a case of rapidly progressive mycosis fungoides in a 68-year-old Caucasian man who initially presented with erythematous plaques characterised by blister formation. Conclusion: Although mycosis fungoides bullosa is extremely rare, it has to be regarded as an important clinical subtype of cutaneous T-cell lymphoma. Mycosis fungoides bullosa represents a particularly aggressive form of mycosis fungoides and is associated with a poor prognosis. The rapid disease progression in our patient confirms bulla formation as an adverse prognostic sign in cutaneous T-cell lymphoma

    Electronic structure and spectroscopy of the quaternary Heusler alloy Co2_2Cr1x_{1-x}Fex_{x}Al

    Full text link
    Quaternary Heusler alloys Co2_2Cr1x_{1-x}Fex_{x}Al with varying Cr to Fe ratio xx were investigated experimentally and theoretically. The electronic structure and spectroscopic properties were calculated using the full relativistic Korringa-Kohn-Rostocker method with coherent potential approximation to account for the random distribution of Cr and Fe atoms as well as random disorder. Magnetic effects are included by the use of spin dependent potentials in the local spin density approximation. Magnetic circular dichroism in X-ray absorption was measured at the L2,3L_{2,3} edges of Co, Fe, and Cr of the pure compounds and the x=0.4x=0.4 alloy in order to determine element specific magnetic moments. Calculations and measurements show an increase of the magnetic moments with increasing iron content. Resonant (560eV - 800eV) soft X-ray as well as high resolution - high energy (3.5\geq 3.5keV) hard X-ray photo emission was used to probe the density of the occupied states in Co2_2Cr0.6_{0.6}Fe0.4_{0.4}Al.Comment: J.Phys.D_Appl.Phys. accepte

    Generalized quantum potentials in scale relativity

    Full text link
    We first recall that the system of fluid mechanics equations (Euler and continuity) that describes a fluid in irrotational motion subjected to a generalized quantum potential (in which the constant is no longer reduced to the standard quantum constant hbar) is equivalent to a generalized Schrodinger equation. Then we show that, even in the case of the presence of vorticity, it is also possible to obtain, for a large class of systems, a Schrodinger-like equation of the vectorial field type from the continuity and Euler equations including a quantum potential. The same kind of transformation also applies to a classical charged fluid subjected to an electromagnetic field and to an additional potential having the form of a quantum potential. Such a fluid can therefore be described by an equation of the Ginzburg-Landau type, and is expected to show some superconducting-like properties. Moreover, a Schrodinger form can be obtained for the fluctuating rotational motion of a solid. In this case the mass is replaced by the tensor of inertia, and a generalized form of the quantum potential is derived. We finally reconsider the case of a standard diffusion process, and we show that, after a change of variable, the diffusion equation can also be given the form of a continuity and Euler system including an additional potential energy. Since this potential is exactly the opposite of a quantum potential, the quantum behavior may be considered, in this context, as an anti-diffusion.Comment: 33 pages, submitted for publicatio

    Strongly Enhanced Backward Emission of Electrons in Transfer and Ionization

    Get PDF
    We studied three-dimensional angular distributions and longitudinal momentum spectra of electrons ejected in transfer plus ionization (TI), i.e., the ejection of one and the capture of a second target electron, for ion-helium collisions. We observe a pronounced structure strongly focused opposite to the projectile beam direction, which we associate with a new correlated TI mechanism proposed recently. This process contributes significantly to the total cross sections over a broad range of perturbations η, even at η as large as 0.5, where uncorrelated TI mechanisms were thought to be dominant

    Constraining parameter space in type-II two-Higgs doublet model in light of a 126 GeV Higgs boson

    Full text link
    We explore the implications of a 126 GeV Higgs boson indicated by the recent LHC results for two-Higgs doublet model (2HDM). Identifying the 126 GeV Higgs boson as either the lighter or heavier of CP even neutral Higgs bosons in 2HDM, we examine how the masses of Higgs fields and mixing parameters can be constrained by the theoretical conditions and experimental constraints. The theoretical conditions taken into account are the vacuum stability, perturbativity and unitarity required to be satisfied up to a cut-off scale. We also show how bounds on the masses of Higgs bosons and mixing parameters depend on the cut-off scale. In addition, we investigate whether the allowed regions of parameter space can accommodate particularly the enhanced di-photon signals, ZZ* and WW* decay modes of the Higgs boson, and examine the prediction of the signal strength of Z{\gamma} decay mode for the allowed regions of the parameter space.Comment: To be published in JHEP, 20 pages, 11 figures, Figures and results are updated for the recent LHC result

    Fibre bundle formulation of nonrelativistic quantum mechanics: I. Introduction. The evolution transport

    Full text link
    We propose a new systematic fibre bundle formulation of nonrelativistic quantum mechanics. The new form of the theory is equivalent to the usual one but it is in harmony with the modern trends in theoretical physics and potentially admits new generalizations in different directions. In it a pure state of some quantum system is described by a state section (along paths) of a (Hilbert) fibre bundle. Its evolution is determined through the bundle (analogue of the) Schr\"odinger equation. Now the dynamical variables and the density operator are described via bundle morphisms (along paths). The mentioned quantities are connected by a number of relations derived in this work. The present first part of this investigation is devoted to the introduction of basic concepts on which the fibre bundle approach to quantum mechanics rests. We show that the evolution of pure quantum-mechanical states can be described as a suitable linear transport along paths, called evolution transport, of the state sections in the Hilbert fibre bundle of states of a considered quantum system.Comment: 26 standard (11pt, A4) LaTeX 2e pages. The packages AMS-LaTeX and amsfonts are required. Revised: new material, references, and comments are added. Minor style chages. Continuation of quan-ph/9803083. For continuation of the this series see http://www.inrne.bas.bg/mathmod/bozhome

    On the avoidability of breast cancer in industrialized societies: older mean age at first birth as an indicator of excess breast cancer risk

    Get PDF
    Background Breast cancer incidence continuous to increase. We examined at population level the association between the relative excess risk of breast cancer and previous age of mother at first birth. Method Incidence of breast cancer in 34 industrialized countries was obtained from the GLOBOCAN 2002 and SEER databases. Data on age of mother at first birth was collected through national statistics offices. National relative excess risk (RER) was calculated by subtracting the lowest age-specific incidence rate from the rate in each population, and dividing the difference by the latter. Results The national RER in 2002 correlated closely with a higher average age at first birth in 1972, 1982, 1992 and also 2002, Pearson correlation [r] being 0.83, 0.79, 0.72 and 0.61, respectively; P < 0.0001. RER of breast cancer in 2002 for those aged 15–44 years correlated closely with the mean age at first birth in 1982 and 1992 (r: 0.81 and 0.75; P < 0.0001), whereas RER for those aged 45–54 years correlated strongly with age at first birth in 1972 and 1982 (r: 0.81 and 0.76; P < 0.0001), and for those aged 55–64 years with age at first birth in 1972 (r: 0.77; P < 0.0001). Conclusions The rising age at first childbirth of mothers has been followed by marked increases in breast cancer incidence. Later age at first birth seems to characterize secular diffusion of ‘modern’ lifestyles with a potentially large impact on increased breast cancer risk, and hence should be accompanied by greater opportunities for prevention through modifiable risk factors

    Presence of depression and anxiety before and after coronary artery bypass graft surgery and their relationship to age

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>Scientific literature on depression and anxiety in patients with coronary heart disease (CHD) consistently reports data of elevated anxiety and depression scores indicating clinically relevant quantities of these psychopathological conditions. Depression is considered to be a risk factor for the development of CHD and deteriorates the outcome after cardiac rehabilitation efforts. The aim of our study was to evaluate the presence of clinically relevant anxiety and depression in patients before and after coronary artery bypass grafting (CABG). Additionally we evaluated their relationship to age because of the increasing number of elderly patients undergoing CABG surgery.</p> <p>Methods</p> <p>One hundred and forty-two consecutive patients who underwent CABG in our hospital were asked to fill in the "Hospital Anxiety and Depression Scale – German Version (HADS)" to measure depression and anxiety scores two days before and ten days after CABG surgery. Differences between these pre- and post-surgical scores were then calculated as means for changes, and the amount of elevated scores were appraised. In order to investigate the relationship between age and anxiety and depression, respectively, Spearman correlations between age and the difference scores were calculated. In addition, ANOVA procedures with the factor "age group" and McNemar tests were calculated. Therefore the sample was divided into four equally sized age groups.</p> <p>Results</p> <p>25.8% of the patients were clinically depressed before and 17.5% after surgery; 34.0% of the patients were clinically anxious before and 24.7% after surgery. This overall change is not significant. We found a significant negative correlation between age and the difference between the two time points for anxiety (Spearman rho = -.218; p = 0.03), but not for depression (Spearman rho = -.128; p = 0.21). ANOVA and McNemar-Tests revealed that anxiety scores and the number of patients high in anxiety declined statistically meaningful only in the youngest patient group. Such a relationship could not be found for depression.</p> <p>Conclusion</p> <p>Our data show a relationship between age and anxiety. Younger patients are more anxious before CABG surgery than older ones and show a decline in symptoms while elderly patients show hardly any change.</p

    Spintronics: Fundamentals and applications

    Get PDF
    Spintronics, or spin electronics, involves the study of active control and manipulation of spin degrees of freedom in solid-state systems. This article reviews the current status of this subject, including both recent advances and well-established results. The primary focus is on the basic physical principles underlying the generation of carrier spin polarization, spin dynamics, and spin-polarized transport in semiconductors and metals. Spin transport differs from charge transport in that spin is a nonconserved quantity in solids due to spin-orbit and hyperfine coupling. The authors discuss in detail spin decoherence mechanisms in metals and semiconductors. Various theories of spin injection and spin-polarized transport are applied to hybrid structures relevant to spin-based devices and fundamental studies of materials properties. Experimental work is reviewed with the emphasis on projected applications, in which external electric and magnetic fields and illumination by light will be used to control spin and charge dynamics to create new functionalities not feasible or ineffective with conventional electronics.Comment: invited review, 36 figures, 900+ references; minor stylistic changes from the published versio

    Depression and anxiety in relation to catechol-O-methyltransferase Val158Met genotype in the general population: The Nord-Trøndelag Health Study (HUNT)

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>The catechol-O-methyltransferase (COMT) gene contains a functional polymorphism, Val158Met, which has been linked to anxiety and depression, but previous results are not conclusive. The aim of the present study was to examine the relationship between the Val158Met COMT gene polymorphism and anxiety and depression measured by the Hospital Anxiety and Depression Scale (HADS) in the general adult population.</p> <p>Methods</p> <p>In the Nord-Trøndelag Health Study (HUNT) the association between the Val158Met polymorphism and anxiety and depression was evaluated in a random sample of 5531 individuals. Two different cut off scores (≥ 8 and ≥ 11) were used to identify cases with anxiety (HADS-A) and depression (HADS-D), whereas controls had HADS-A <8 and HADS-D <8.</p> <p>Results</p> <p>The COMT genotype distribution was similar between controls and individuals in the groups with anxiety and depression using cut-off scores of ≥ 8. When utilizing the alternative cut-off score HADS-D ≥ 11, Met/Met genotype and Met allele were less common among men with depression compared to the controls (genotype: p = 0.017, allele: p = 0.006). In the multivariate analysis, adjusting for age and heart disease, depression (HADS-D ≥ 11) was less likely among men with the Met/Met genotype than among men with the Val/Val genotype (OR = 0.37, 95% CI = 0.18–0.76).</p> <p>Conclusion</p> <p>In this population-based study, no clear association between the Val158Met polymorphism and depression and anxiety was revealed. The Met/Met genotype was less likely among men with depression defined as HADS-D ≥ 11, but this may be an incidental finding.</p
    corecore