Cytokines and depression in cancer patients and caregivers.

Objective:A better understanding of the biobehavioral mechanisms underlying depression in cancer is required to translate biomarker findings into clinical interventions. We tested for associations between cytokines and the somatic and psychological symptoms of depression in cancer patients and their healthy caregivers. Patients and methods:The GRID Hamilton Rating Scale for Depression (Ham-D) was administered to 61 cancer patients of mixed type and stage, 26 primary caregivers and 38 healthy controls. Concurrently, blood was drawn for multiplexed plasma assays of 15 cytokines. Multiple linear regression, adjusted for biobehavioral variables, identified cytokine associations with the psychological (Ham-Dep) and somatic (Ham-Som) subfactors of the Ham-D. Results:The Ham-Dep scores of cancer patients were similar to their caregivers, but their Ham-Som scores were significantly higher (twofold, p=0.016). Ham-Som was positively associated with IL-1ra (coefficient: 1.27, p≤0.001) in cancer patients, and negatively associated with IL-2 (coefficient: -0.68, p=0.018) in caregivers. Ham-Dep was negatively associated with IL-4 (coefficient: -0.67, p=0.004) in cancer patients and negatively associated with IL-17 (coefficient: -1.81, p=0.002) in caregivers. Conclusion:The differential severity of somatic symptoms of depression in cancer patients and caregivers and the unique cytokine associations identified with each group suggests the potential for targeted interventions based on phenomenology and biology. The clinical implication is that depressive symptoms in cancer patients can arise from biological stressors, which is an important message to help destigmatize the development of depression in cancer patients

Electroweak Measurements Using Heavy Quarks Identified in e+e−e^{+}e^{-} Annihilation

Since 1989, the Large Electron Positron collider at CERN has been used to study elec- troweak physics to an unprecedented precision. The data have acted as spectacular confirmation of the Standard Model as the best description of electroweak interac- tions at scales of - 100 GeV. However, in 1995, a possible anomaly appeared in the LEP measurement of Rb = (Z-adbb) which was more than three standard devia- ( Z-*hadrons) tions above the Standard Model prediction. This effect could not be accounted for by minor adjustment of model parameters, in particular the mass of the top quark which had recently been directly measured at the Fermilab Tevatron. In order to investigate whether the deviation could be an indication of physics beyond the Standard Model we present new precise measurements of both Rb and the forward-backward asymme- try of b quark production, AbFB , using -63 pb - 1 of data at the Z peak recorded by the L3 detector during 1994-95. The results are: Rb = 0.2146 ± 0.0017(stat) + 0.00 3 3 (sys) - 0.139 (R, - 0.171) AbFB = 9.33 ± 1.40(stat) ± 0.65(sys) ± 0.10(QCD)% This value for Rb agrees with the Standard Model to within one standard deviation. AFB leads to a value for the effective weak mixing angle for b-quarks sin 2 eff - 0.2333 ± 0.0025(stat) ± 0.0012(sys) which is consistent with values obtained using different decay modes of the Z and from neutrino physics, supporting flavour universality. We thus observe no deviation from the Standard Model and, from the Rb measurement, limit the effects of new physics to < 1.7% in b decay

Theoretical studies of the kinetics of mechanical unfolding of cross-linked polymer chains and their implications for single molecule pulling experiments

We have used kinetic Monte Carlo simulations to study the kinetics of unfolding of cross-linked polymer chains under mechanical loading. As the ends of a chain are pulled apart, the force transmitted by each crosslink increases until it ruptures. The stochastic crosslink rupture process is assumed to be governed by first order kinetics with a rate that depends exponentially on the transmitted force. We have performed random searches to identify optimal crosslink configurations whose unfolding requires a large applied force (measure of strength) and/or large dissipated energy (measure of toughness). We found that such optimal chains always involve cross-links arranged to form parallel strands. The location of those optimal strands generally depends on the loading rate. Optimal chains with a small number of cross-links were found to be almost as strong and tough as optimal chains with a large number of cross-links. Furthermore, optimality of chains with a small number of cross-links can be easily destroyed by adding cross-links at random. The present findings are relevant for the interpretation of single molecule force probe spectroscopy studies of the mechanical unfolding of load-bearing proteins, whose native topology often involves parallel strand arrangements similar to the optimal configurations identified in the study

On Properties of the Isoscalar Giant Dipole Resonance

Main properties (strength function, energy-dependent transition density, branching ratios for direct nucleon decay) of the isoscalar giant dipole resonance in several medium-heavy mass spherical nuclei are described within a continuum-RPA approach, taking into account the smearing effect. All model parameters used in the calculations are taken from independent data. Calculation results are compared with available experimental data.Comment: 12 pages, 2 figure

Lateral current density fronts in asymmetric double-barrier resonant-tunneling structures

We present a theoretical analysis and numerical simulations of lateral current density fronts in bistable resonant-tunneling diodes with Z-shaped current-voltage characteristics. The bistability is due to the charge accumulation in the quantum well of the double-barrier structure. We focus on asymmetric structures in the regime of sequential incoherent tunneling and study the dependence of the bistability range, the front velocity and the front width on the structure parameters. We propose a sectional design of a structure that is suitable for experimental observation of front propagation and discuss potential problems of such measurements in view of our theoretical findings. We point out the possibility to use sectional resonant-tunneling structures as controllable three-terminal switches.Comment: to appear in J.Appl.Phy

Evaluation of the mean intensity of the P-odd mixing of nuclear compound states

A temperature version of the shell-optical-model approach for describing the low-energy compound-to-compound transitions induced by external single-particle fields is given. The approach is applied to evaluate the mean intensity of the P-odd mixing of nuclear compound states. Unified description for the mixing and electromagnetic transitions allows one to evaluate the mean intensity without the use of free parameters. The valence-mechanism contribution to the mentioned intensity is also evaluated. Calculation results are compared with the data deduced from cross sections of relevant neutron-induced reactions.Comment: LaTeX, 10 page

Approximation of conformal mappings using conformally equivalent triangular lattices

Consider discrete conformal maps defined on the basis of two conformally equivalent triangle meshes, that is edge lengths are related by scale factors associated to the vertices. Given a smooth conformal map $f$, we show that it can be approximated by such discrete conformal maps $f^\epsilon$. In particular, let $T$ be an infinite regular triangulation of the plane with congruent triangles and only acute angles (i.e.\ $<\pi/2$). We scale this tiling by $\epsilon>0$ and approximate a compact subset of the domain of $f$ with a portion of it. For $\epsilon$ small enough we prove that there exists a conformally equivalent triangle mesh whose scale factors are given by $\log|f'|$ on the boundary. Furthermore we show that the corresponding discrete conformal maps $f^\epsilon$ converge to $f$ uniformly in $C^1$ with error of order $\epsilon$.Comment: 14 pages, 3 figures; v2 typos corrected, revised introduction, some proofs extende

Mental health literacy of negative body image: symptom recognition and beliefs about body image in a British community sample

The present study examined mental health literacy of negative body image in a sample of 485 British adults. Participants were presented with vignettes of a fictional woman (‘Kate’) and man (‘Jack’) suffering from negative body image and were asked questions addressing symptom recognition, distress, sympathy and sources of help-seeking. Participants also completed measures of body appreciation and psychiatric skepticism. Results showed that less than a fifth of participants correctly identified the vignettes as depicting cases of negative body image. The vignette describing Kate was rated as significantly more distressing, deserving of sympathy and requiring help than that of Jack. Women rated the conditions described by both vignettes as significantly more distressing and requiring help than did men. Psychiatric skepticism and body appreciation were significantly associated with beliefs about the vignettes. Implications of the results for the promotion of mental health literacy in relation to body image are discussed

Discrete complex analysis on planar quad-graphs

We develop a linear theory of discrete complex analysis on general quad-graphs, continuing and extending previous work of Duffin, Mercat, Kenyon, Chelkak and Smirnov on discrete complex analysis on rhombic quad-graphs. Our approach based on the medial graph yields more instructive proofs of discrete analogs of several classical theorems and even new results. We provide discrete counterparts of fundamental concepts in complex analysis such as holomorphic functions, derivatives, the Laplacian, and exterior calculus. Also, we discuss discrete versions of important basic theorems such as Green's identities and Cauchy's integral formulae. For the first time, we discretize Green's first identity and Cauchy's integral formula for the derivative of a holomorphic function. In this paper, we focus on planar quad-graphs, but we would like to mention that many notions and theorems can be adapted to discrete Riemann surfaces in a straightforward way. In the case of planar parallelogram-graphs with bounded interior angles and bounded ratio of side lengths, we construct a discrete Green's function and discrete Cauchy's kernels with asymptotics comparable to the smooth case. Further restricting to the integer lattice of a two-dimensional skew coordinate system yields appropriate discrete Cauchy's integral formulae for higher order derivatives.Comment: 49 pages, 8 figure

Pulsar timing analysis in the presence of correlated noise

Pulsar timing observations are usually analysed with least-square-fitting procedures under the assumption that the timing residuals are uncorrelated (statistically "white"). Pulsar observers are well aware that this assumption often breaks down and causes severe errors in estimating the parameters of the timing model and their uncertainties. Ad hoc methods for minimizing these errors have been developed, but we show that they are far from optimal. Compensation for temporal correlation can be done optimally if the covariance matrix of the residuals is known using a linear transformation that whitens both the residuals and the timing model. We adopt a transformation based on the Cholesky decomposition of the covariance matrix, but the transformation is not unique. We show how to estimate the covariance matrix with sufficient accuracy to optimize the pulsar timing analysis. We also show how to apply this procedure to estimate the spectrum of any time series with a steep red power-law spectrum, including those with irregular sampling and variable error bars, which are otherwise very difficult to analyse.Comment: Accepted by MNRA