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Preoccupation with alternative outcomes (counterfactual thinking) is a central component of the ruminations of trauma victims. The questions investigated were whether such thinking should be distinguished from general rumination and whether elements of counterfactual thinking might relate to the process of adjustment. A sample of assault victims was interviewed. They completed a battery of self-report scales and thought-listing procedures. Frequency of counterfactual thinking was closely associated with continuing levels of posttraumatic distress. However, high availability of counterfactuals (as indexed by verbal fluency) was related to potentially adaptive outcomes, such as the generation of behavioral plans. In addition, as expected, levels of different aspects of counterfactual thinking were moderated by metacognitive control strategies as a function of time since the trauma. Keywords: posttraumatic stress, rumination, emotional processing, heuristics

New heterophasic granules comprised of two high molecular weight semi‐crystalline components ‐ polyethylene (PE) and isotactic polypropylene (iPP) ‐ are prepared from a MgCl2 supported Zeigler‐Natta catalyst. The impact of order of monomer addition on granule morphology and extent of mixing of PE and iPP in these monomer‐to‐polymer scenarios are examined. In one polymerization propylene is followed by ethylene (iPP‐PE; 1), and in the second ethylene is followed by propylene (PE‐iPP; 2). Detailed morphological assessments were carried out on RuO4 stained sections of the nascent granules of these heterophasic products using low voltage scanning electron microscopy (LVSEM) and scanning transmission electron microscopy (STEM). In these side‐by‐side granule morphology comparisons, LVSEM, which has not been used for granule examinations, has proved to be invaluable, typically providing insights into phase morphology that STEM does not. Both polymerizations 1 and 2 result in intimate mixing of PE and iPP on the tens to hundreds of nanometer scale. However, morphological outcomes for 1 and 2 are markedly different. In the case of 1, comprising 31 wt% iPP and 69 wt% of PE (the second‐grown phase), a reticulated mesh network of PE is readily observed coursing through much of the first produced iPP globular and sub‐globular matrix. The PE fibrils that comprise this network are remarkably uniform in diameter; approximately 100–150 nm. This aspect of the morphology is consistent with a PE sheath encapsulating both iPP globules and sub‐globules commonly found in iPP homopolymer granules made with MgCl2 catalysts. This morphology is similar to that of the most extensively studied heterophasic granules, classic iPP‐ethylene‐propylene rubber (EPR) impact copolymer (ICP), where the second grown EPR fills in space between and around the iPP globules and sub‐globules. Thus, the dominant morphology of 1 is consistent with the often‐called pore‐filling model. Using the same catalyst and arriving at a similar global composition (65 wt% PE and 35 wt% iPP), sample 2 is produced through the reverse order of monomer addition. The dominant morphology for 2 cannot be explained by the pore‐filling model. Instead, LVSEM most clearly shows that the second grown iPP phase, is finely dispersed throughout the PE matrix (not outside it) as irregularly shaped inclusions that are nominally 100 to 400 nm in diameter, so the dominant morphology in 2 is consistent with the proposed but not previously observed core‐shell model. The STEM results for 2 also reveal the presence of primitive PE spherulites and organized PE lamellae in the granules; structures not found in 1 and apparently not reported before in polyethylene homopolymer granules. These structures form likely from heat released during ethylene polymerization in the first step in 2. In LVSEM, the PE and iPP phases provide different amplitude contrast (grayscale) that is useful for calibration. In the LVSEM images of both samples 1 and 2, non‐binary strong grayscale gradients are observed in many regions in the micrographs. These suggest, but do not yet prove, fine dispersion of some PE in the first formed iPP (1) as well as a fine dispersion, perhaps on the ~10 nm scale, of some iPP in the first formed PE (2). So even granules of 1 appear to have some hybrid quality; primarily pore‐filling, with some core‐shell result as well. Finally, in STEM images of both 1 and 2 well‐formed, long PE lamella provide occasional marked contrast (especially at boundaries) with nascent iPP, which exists in a microparacrystalline state (short, poorly formed crystals). Regardless of the morphological complexity, the exceedingly fine mixing of the two semi‐crystalline phases accomplished during dilation of the granules to accommodate each second produced crystallizable polymer offers the potential for utility of these heterophasic granules in materials design (grafting and cross‐coupling, for example). [ABSTRACT FROM AUTHOR]

A generalized climate of distrust in political institutions is not functional to healthy democracies. With the advent of social media, recent scholarly efforts attempt to better understand people's conspiracy theory beliefs in inhibiting institutional trust. This study contributes to this literature by considering the direct antecedent effects of uncertainty avoidance and the moderating role of active social media use—SMU (i.e., interactional SMU, informational SMU, and political expressive SMU). The former is theorized to enable conspiracy theories to thrive, while the latter should cushion the negative effects of conspiracy beliefs on institutional trust. Relying on diverse survey data across different cultures from Europe, the Americas, and New Zealand (N = 11,958) and applying structural equation modeling, findings supported the hypothesized model. In high uncertainty‐avoidance societies, where less well‐known situations are perceived as uncomfortable or downright threatening, conspiracy beliefs proliferate and negatively impact institutional trust. Active SMU attenuates these effects. Via social media, citizens have the ability to strengthen social relationships (interactional SMU), keep themselves informed about the community (informational SMU), and engage in political self‐expression (political expressive SMU), which mitigate conspiracy‐belief negative effects on institutional trust. Future research implications and key limitations of the study are all discussed. [ABSTRACT FROM AUTHOR]

The intent of this paper is to predict the effects of random edge roughness on the knife-edge diffraction of an incident wave. This has been accomplished by approximating the field beyond the diffracting half plane with spectral techniques and the Kirchhoff approximation. By restricting the point of observation of the diffracted field to the side opposite from the incident field and not too far into the shadow zone of the edge, the results for a straight knife edge should be very accurate. By similarly restricting the spatial frequency spectrum of the knife-edge roughness to contain no frequencies comparable to or shorter than the electromagnetic wavenumber, the method used to estimate the effects of the roughness is also accurate. The relationships developed for the mean or average diffracted field and the incoherent diffracted power are studied for a range of electrophysical parameters that are representative of the situation encountered in a point-to-point communications link with blockage by a rough-edged half plane. The interpretation of the results is facilitated by the observation that the total diffracted field is a superposition of the incident field and the edge-diffracted field. Thus, the conventional oscillating behavior of the total field as the point of observation recedes from the edge and is attributed to the phase interference between these two fields. When the roughness on the edge increases, the edge diffracted-field becomes more incoherent and the phase interference diminishes; this leads to an attenuation of the oscillations in the coherent or mean total field. The model also predicts that the incoherent power is strongest near to the rough knife and is not generally appreciable when the point of observation of the diffracted field is far away from the edge. This, of course, is in complete agreement with our understanding that shadows, and hence, the details of the shadow-causing boundary (knife-edge), exists only a finite distance behind the boundary. Index Terms--Diffraction, electromagnetic edge diffraction, rough surfaces.

The validity of the lowest order small slope approximation [SSA(1)] and the extended Kirchhoff approach (EKA) by Elfouhaily et al. has been studied by comparing the Doppler spectra of the backscattered signals predicted by these models to their counterparts from exact integral equation-based numerical simulations. The study is conducted at L and S bands (electromagnetic wavelengths 23 and 10 cm); the rough ocean-like surfaces correspond to the wind speed of 5 m/s and were generated using both linear and nonlinear (Creamer) models. The incidence angle varies from normal to low grazing. Expressions for the two analytical models possess many similarities but contain different incidence/scattering angle-dependent factors. The analysis of the bistatic scattering cross sections predicted by the two models reveals that SSA(1) follows the exact numerical results more closely than the EKA. Moreover, at horizontal polarization the extended Kirchhoff bistatic cross section displays certain anomalies (unlimited growth at grazing scattering angles) that are indicative of the problems with this model. However, in the backscattering direction, the expressions for the two models are identical. Doppler analysis of the backscattered signals shows that in general, the analytical models provide better agreement with the numerical results for smaller incident angles. In addition, the agreement between the models and the exact numerical simulations is always better in the case of vertical polarization for which the analytical models give a satisfactory prediction of the Doppler spectrum for incident angles as large as 85 [degrees] from the normal for both linear and nonlinear surfaces. For horizontal polarization, the models give increasingly poor predictions of the shape, magnitude, and location of the Doppler spectrum for incident angles in the range from 60 [degrees] to low grazing. Doppler analysis proves to be a much more precise and sensitive tool in assessing the scattering model's validity than the usual comparison of cross sections. Index Terms--Doppler spectrum, electromagnetic scattering by rough surfaces, integral equation methods, low grazing angles, numerical methods, Pierson-Moskowitz spectrum.

Aim: To ascertain the effect of serious systemic comorbidities upon the quality of life of patients with ophthalmic diseases. Methods: Time tradeoff utility values were obtained in consecutive ophthalmic patients [...]

Abstract Better information about how to use new technologies more effectively in higher education is essential, especially given the current rapidly changing environment in higher education. This paper summarizes the [...]

Results from a Monte Carlo simulation of backscattering from one-dimensional (1-D) time-evolving sea surface models are reported. A numerical electromagnetic method based on an accelerated forward-backward approach is used to calculate backscattered returns from impedance surface profiles at incidence angles of 0 [degrees] (normal), 40 [degrees], and 80 [degrees]. Surfaces are initialized as realizations of a Pierson-Moskowitz spectrum and then stepped in time through a numerical hydrodynamic method. Results from three distinct hydrodynamic methods are compared: a linear evolution, the 'improved linear representation' of Creamer et al. [7], and the 'Watson-West' approach of West et al. in [8]. Instabilities in the West model due to formation of steep wave features limit the study to L-band backscattering for wind speeds less than 2 m/s, so that the surfaces considered are only slightly rough on an electromagnetic scale. The small slope approximation for electromagnetic scattering is shown to provide reasonable predictions in this limit. Statistics of the resulting surface profiles and backscattered fields are compared for the three models and are found to be similar in most respects. Backscattered field Doppler spectra, however, show differences, with the West model apparently capturing more nonlinear interactions in the surface evolution. Index Terms--Doppler spectrum, rough surface scattering, sea scattering.