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The problem of a hydrogen atom in a strong magnetic field is a notorious example of a quantum system that has genuinely different asymptotic behaviors in different directions. In the direction perpendicular to the magnetic field the motion is quadratically confined, while in the direction along the field line the motion is a Coulomb-distorted free motion. In this work, we identify the asymptotically relevant parts of the Hamiltonian and cast the problem into a Lippmann-Schwinger form. Then, we approximate the asymptotically irrelevant parts by a discrete Hilbert space basis that allows an exact analytic evaluation of the relevant Green’s operators by continued fractions. The total asymptotic Green’s operator is calculated by a complex contour integral of subsystem Green’s operators. We present a sample of numerical results for a wide range of magnetic field strengths.

IntroductionPsychological factors, such as emotional regulation strategies, play a crucial role in the management and care of chronic somatic health conditions among adolescents. In the existing literature, catastrophising has been associated negatively with health-related quality of life in the context of chronic health conditions in general. However, there is limited knowledge about its role in specific illness types.ObjectivesWe aimed to evaluate the impact of catastrophising on the health-related quality of life in two distinct illness groups: diabetes and oncology, within a Hungarian sample.MethodsA cross-sectional study using self-report measures was carried out, involving a total of 273 adolescents (mean age: 14.72 years, SD: 1,82 years; 50.2% females) in the two paediatric samples. The diabetes group consisted of 171 participants, while the oncology group was comprised of 102 individuals. No significant differences were found between the two chronic condition groups in terms of gender (χ2 = 116.51; p = 0.50), or mean age (F(-0.82; 0.77) = 1.66; p = 0.19). The short-version of the Cognitive Emotion Regulation Questionnaire (CERQ-short) was used to assess the cognitive emotional regulation strategies of the children, specifically focusing on the catastrophising subscale. Health-related quality of life was measured using the 4.0 version of the PedsQL, which included subscales for Physical, Emotional, Social, and School Functioning.ResultsA Hayes-moderation analysis with an interaction effect was conducted, controlling for gender, age, and the duration of the illness. A significant interaction effect was observed between catastrophising and the illness groups, impacting School Functioning (F(1, 243) = 4.17; p = 0.04), Physical Functioning (F(1, 245) = 4.67; p = 0.03), Social Functioning (F(1, 245) = 4,23; p = 0.04), and Emotional Functioning (F(1, 245) = 4.20; p = 0.04). The association between catastrophising and health-related quality of life remained stronger in the oncology group.ConclusionsCatastrophising appears to be a risk factor that affects the quality of life of children facing oncology illnesses. Therefore, addressing catastrophising in interventions tailored to this paediatric illness group may be beneficial.Keywords: catastrophising, health-related quality of life, adolescents, chronic somaticThis study was supported by the Hungarian National Research, Development and Innovation Office (K143764).Disclosure of InterestNone Declared

We propose a computational method for relativistic spin-1/2 particles by solving the corresponding Feshbach–Villars equation. We have found that the Feshbach–Villars spin-1/2 Hamiltonian can be written as two spin-coupled Feshbach–Villars spin-0 Hamiltonians. For the solution method, we adopted an integral equation formalism. The potential operators are represented in a discrete Hilbert space basis and the relevant Green’s operator has been calculated by a matrix continued fraction.

A computational method is proposed to calculate bound and resonant states by solving the Klein–Gordon and Dirac equations for real and complex energies, respectively. The method is an extension of a non-relativistic one, where the potential is represented in a Coulomb–Sturmian basis. This basis facilitates the exact analytic evaluation of the Coulomb Green’s operator in terms of a continued fraction. In the extension to relativistic problems, we cast the Klein–Gordon and Dirac equations into an effective Schrödinger form. Then the solution method is basically an analytic continuation of non-relativistic quantities like the angular momentum, charge, energy and potential into the effective relativistic counterparts.

1. Urbanized habitats differ from natural ones in several ecological features, including climate, food availability, strength of predation and competition. Although the effects of urbanization on avian community composition are well known, there is much less information about how individual birds are affected by these human-generated habitat differences. 2. In this study we investigated the relationships between the morphological characteristics and the degree of habitat urbanization in house sparrows, Passer domesticus (Linne 1758) . We collected data for more than 1000 non-breeding adult birds in Hungary between 1997 and 2006, from seven sites including farmlands, suburban areas and city centres. 3. We found that the body mass, tarsus length and body condition of free-living sparrows differed among the sites: birds in more urbanized habitats were consistently smaller and in worse condition than birds in more rural habitats. A composite measure of habitat urbanization (based on building density, road density and vegetation cover) explained over 75% of variance between sites in the studied traits, after we controlled for the effects of sex, year, season and time of capture. 4. The difference in body mass between rural and urban sparrows was significant when birds were kept in aviaries under identical conditions, with constant ad libitum food availability. It is therefore unlikely that the reduced body size and condition of urban sparrows are a consequence of reduced access to food for adults (e.g. due to strong competition), or their short-term responses to high food predictability (e.g. by strategic mass regulation). 5. We suggest that habitat differences in nestling development or adaptive divergence of sparrow populations due to distinct environmental conditions (such as differing predation pressure) may account for the differences along the urbanization gradient.

Levosimendan, a calcium sensitizer and potassium channel-opener, is widely appreciated by many specialist heart failure practitioners for its effects on systemic and pulmonary hemodynamics and for the relief of symptoms of acute heart failure. The drug’s impact on mortality in large randomized controlled trials has been inconsistent or inconclusive but, in contrast to conventional inotropes, there have been no indications of worsened survival and some signals of improved heart failure-related quality of life. For this reason, levosimendan has been proposed as a safer inodilator option than traditional agents in settings, such as advanced heart failure. Positive effects of levosimendan on renal function have also been described. At the HEART FAILURE 2018 congress of the Heart Failure Association of the European Society of Cardiology, safe and effective use levosimendan in acute and advanced heart failure was examined in a series of expert tutorials. The proceedings of those tutorials are summarized in this review, with special reference to advanced heart failure and heart failure with concomitant renal dysfunction. Meta-analysis of clinical trials data is supportive of a renal-protective effect of levosimendan, while physiological observations suggest that this effect is exerted at least in part via organ-specific effects that may include selective vasodilation of glomerular afferent arterioles and increased renal blood flow, with no compromise of renal oxygenation. These lines of evidence require further investigation and their clinical significance needs to be evaluated in specifically designed prospective trials.

Traffic congestion in highway networks is one of the main issues to be addressed by today's traffic management schemes. Automation combined with the increasing market penetration of on-line communication, navigation and advanced driver assistance systems will ultimately result in intelligent vehicle highway systems (IVHS), that distribute intelligence between roadside infrastructure and vehicles and that -- in particular on the longer term -- are one of the most promising solutions to the traffic congestion problem. In this study, the authors present, a survey on traffic management and control frameworks for IVHS. First, they give a short overview of the main currently used traffic control methods for freeways. Next, they discuss IVHS-based traffic control measures. Then, various traffic management architectures for IVHS, such as PATH, Dolphin, Auto21 CDS etc., are discussed and a comparison of the various frameworks is presented. Finally, the authors sketch, how existing traffic control methodologies could fit in an IVHS-based traffic control set-up.

We propose a solution method for studying relativistic spin-0 particles. We adopt the Feshbach–Villars formalism of the Klein–Gordon equation and express the formalism in an integral equation form. The integral equation is represented in the Coulomb–Sturmian basis. The corresponding Green’s operator with Coulomb and linear confinement potential can be calculated as a matrix continued fraction. We consider Coulomb plus short range vector potential for bound and resonant states and linear confining scalar potentials for bound states. The continued fraction is naturally divergent at resonant state energies, but we made it convergent by an appropriate analytic continuation.

Few studies have included subjects with the propensity to reach old age in good health, with the aim to disentangle mechanisms contributing to staying healthier for longer. The hypothalamic-pituitary-thyroid (HPT) axis maintains circulating levels of thyroid stimulating hormone (TSH) and thyroid hormone (TH) in an inverse relationship. Greater longevity has been associated with higher TSH and lower TH levels, but mechanisms underlying TSH/TH differences and longevity remain unknown. The HPT axis plays a pivotal role in growth, development and energy metabolism. We report that offspring of nonagenarians with at least one nonagenarian sibling have increased TSH secretion but similar bioactivity of TSH and similar TH levels compared to controls. Healthy offspring and spousal controls had similar resting metabolic rate and core body temperature. We propose that pleiotropic effects of the HPT axis may favour longevity without altering energy metabolism.

The Feshbach–Villars equations, like the Klein–Gordon equation, are relativistic quantum mechanical equations for spin-0 particles.We write the Feshbach–Villars equations into an integral equation form and solve them by applying the Coulomb–Sturmian potential separable expansion method. We consider boundstate problems in a Coulomb plus short range potential. The corresponding Feshbach–Villars CoulombGreen’s operator is represented by a matrix continued fraction.