THORACOSCOPY - DIAGNOSTIC AND THERAPEUTIC OPPORTUNITIES IN SURGICAL CHEST DISEASES

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A Short Form Of The Maximization Scale: Factor Structure, Reliability And Validity Studies

We conducted an analysis of the 13-item Maximization Scale (Schwartz et al., 2002) with the goal of establishing its factor structure, reliability and validity. We also investigated the psychometric properties of several proposed refined versions of the scale. Four sets of analyses are reported. The first analysis confirms the 3-part factor structure of the scale and assesses its reliability. The second analysis identifies those items that do not perform well on the basis of internal, external, and judgmental criteria, and develops three shorter versions of the scale. In the third analysis, the three refined versions of the scale are cross-validated to confirm dimensionality, reliability, and validity. The fourth analysis uses an experiment in an investment decision making context to assess the reliability and nomological validity of the refined scales. These analyses lead us to conclude that a shorter, 6-item Maximization Scale performs best and should be used by future researchers. It is hoped that clarification of the conceptual underpinnings of the maximization construct and development of a refined scale will enhance its use among researchers across severa

Upper critical field measurements up to 60 T in arsenic-deficient LaO_(0.9)F_(0.1)FeAs_(1-delta): Pauli limiting behaviour at high fields vs improved superconductivity at low fields

We report resistivity and upper critical field B_c2(T) data for As deficient LaO_(0.9)F_(0.1)FeAs_(1-delta) in a wide temperature and high field range up to 60 T. These disordered samples exhibit a slightly enhanced superconducting transition at T_c = 29 K and a significantly enlarged slope dB_(c2))/dT = -5.4 T/K near T_c which contrasts with a flattening of B_(c2)(T) starting near 23 K above 30 T. This flattening is interpreted as Pauli limiting behaviour (PLB) with B_(c2)(0) approx 63 T. We compare our results with B_(c2)(T)-data reported in the literature for clean and disordered samples. Whereas clean samples show no PLB for fields below 60 to 70 T, the hitherto unexplained flattening of B_(c2)(T) for applied fields H || ab observed for several disordered closely related systems is interpreted also as a manifestation of PLB. Consequences of our results are discussed in terms of disorder effects within the frame of conventional and unconventional superconductivity.Comment: 4 pages, 3 figures, submitted to RHMF09 (9th International Conference on the Research in High Magnetic Fields), Dresden, July 22-25, 200

Low Temperature Transport and Specific Heat Studies of Nd_{1-x}Pb_{x}MnO_{3} Single Crystals

Electrical transport and specific heat properties of Nd_{1-x}Pb_{x}MnO_{3} single crystals for 0.15 < x 0.5 have been studied in low temperature regime. The resistivity in the ferromagnetic insulating (FMI) phase for x < 0.3 has an activated character. The dependence of the activation gap Delta on doping x has been determined and the critical concentration for the zero-temperature metal-insulator transition was determined as x_{c} ~ 0.33. For a metallic sample with x=0.42, a conventional electron-electron (e-e) scattering term proportional T^{2} is found in the low-temperature electrical resistivity, although the Kadowaki-Woods ratio is found to be much larger for this manganite than for a normal metal. For a metallic sample with x=0.5, a resistivity minimum is observed for x= 0.5. The effect is attributed to weak localization and can be described by a negative T^{1/2} weak-localization contribution to resistivity for a disordered three-dimensional electron system. The specific heat data have been fitted to contributions from free electrons (gamma), spin excitations (beta_{3/2}), lattice and a Schottky-like anomaly related to the rare-earth magnetism of the Nd ions. The value of gamma is larger than for normal metals, which is ascribed to magnetic ordering effects involving Nd. Also, the Schottky-like anomaly appears broadened and weakened suggesting inhomogeneous molecular fields at the Nd-sites.Comment: 14 pages, 8 figure

Is satisficing really satisfying? Satisficers exhibit greater threat than maximizers during choice overload.

When selecting from too many options (i.e., choice overload), maximizers (people who search exhaustively to make decisions that are optimal) report more negative post-decisional evaluations of their choices than do satisficers (people who search minimally to make decisions that are sufficient). Although ample evidence exists for differences in responses after-the-fact, little is known about possible divergences in maximizers' and satisficers' experiences during choice overload. Thus, using the biopsychosocial model of challenge/threat, we examined 128 participants' cardiovascular responses as they actively made a selection from many options. Specifically, we focused on cardiovascular responses assessing the degree to which individuals (a) viewed their decisions as valuable/important and (b) viewed themselves as capable (vs. incapable) of making a good choice. Although we found no differences in terms of the value individuals placed on their decisions (i.e., cardiovascular responses of task engagement), satisficers-compared to maximizers-exhibited cardiovascular responses consistent with feeling less capable of making their choice (i.e., greater relative threat). The current work provides a novel investigation of the nature of differences in maximizers'/satisficers' momentary choice overload experiences, suggesting insight into why they engage in such distinct search behaviors

Surprises in the doping dependence of the Fermi surface in Bi(Pb)-2212

A detailed and systematic ARPES investigation of the doping-dependence of the normal state Fermi surface (FS) of modulation-free (Pb,Bi)-2212 is presented. The FS does not change in topology away from hole-like at any stage. The data reveal, in addition, a number of surprises. Firstly the FS area does not follow the usual curve describing Tc vs x for the hole doped cuprates, but is down-shifted in doping by ca. 0.05 holes per Cu site, indicating either the break-down of Luttinger's theorem or the consequences of a significant bi-layer splitting of the FS. Secondly, the strong k-dependence of the FS width is shown to be doping independent. Finally, the relative strength of the shadow FS has a doping dependence mirroring that of Tc.Comment: 5 pages, 4 figures (revtex

Evidence for strong electron-phonon coupling in MgCNi_3

The title compound is investigated by specific heat measurements in the normal and superconducting state supplemented by upper critical field transport, susceptibility and magnetization measurements. From a detailed analysis including also full potential electronic structure calculations for the Fermi surface sheets, Fermi velocities and partial densities of states the presence of both strong electron-phonon interactions and considerable pair-breaking has been revealed. The specific heat and the upper critical field data can be described to first approximation by an effective single band model close to the clean limit derived from a strongly coupled predominant hole subsystem with small Fermi velocities. However, in order to account also for Hall-conductivity and thermopower data in the literature, an effective general two-band model is proposed. This two-band model provides a flexible enough frame to describe consistently all available data within a scenario of phonon mediated s-wave superconductivity somewhat suppressed by sizeable electron-paramagnon or electron-electron Coulomb interaction. For quantitative details the relevance of soft phonons and of a van Hove type singularity in the electronic density of states near the Fermi energy is suggested.Comment: 21 pages, 26 figures (high quality version of figures 2,11 available at http://www.ifw-dresden.de/imw/21/coworker/waelte.priv/

Cognitive Ability, Expectations, and Beliefs about the Future: Psychological Influences on Retirement Decisions

Social Security Administrationhttp://deepblue.lib.umich.edu/bitstream/2027.42/102273/1/wp298.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/102273/4/wp298.pd

Re-Examination Of Maximization: Psychometric Assessment And Derivation Of A Short Form Of The Maximization Scale

This paper provides a psychometric assessment of the 13-item maximization scale developed by Schwartz and colleagues (2002), with the goal of reexamining its factor structure, reliability, and validity. The psychometric properties of several proposed revised versions of the scale are also investigated. The analyses reveal that a shorter, 6-item version of the scale performs better than the original scale and should be considered for use in future studies. Clarification of the conceptual underpinnings of the maximization construct and development of a more psychometrically sound version of the scale should enhance its use among behavioral researchers across several of the social science disciplines