878 research outputs found
Refugees & Violent Group Grievance
Do refugee inflows have an effect on state fragility? In this article I examine whether refugee inflows, commonly associated in the literature with economic and cultural pressures, result in a more fragile state by means of increased violent group grievance. Violent group grievance captures a distinct form of intrastate violence, specifically small-scale hate crimes and ethnic group clashes associated with powerlessness and discrimination. The main hypothesis in this paper is that refugee inflows may increase violent group grievance. I examine the effect of refugee inflows on the level of domestic violent group grievance using quantitative analyses based on original large-N datasets and cross-sectional longitudinal models to fill gaps in the literature on state fragility. This study controls for alternative explanations and covers the time period between 2006 and 2014. The analysis results confirm the main hypothesis of this paper
The Prefix PO- and Aspect in Russian and Polish: A Cognitive Grammar Account
This study examines the meanings of the prefix po- and verbal aspect in Russian and Polish in a Cognitive Grammar framework. The principles of Cognitive Grammar adopted in this study are based on Langacker (1991). This study follows Dickey's (2000) East-West division of aspect, within which the prototypical meanings of the Russian perfective and imperfective aspects are temporal definiteness and qualitative temporal indefiniteness, respectively, and the prototypical meanings of the Polish perfective and imperfective aspects are temporal definiteness/totality and quantitative temporal indefiniteness. According to Cognitive Grammar, the prototype is the most salient node in a network; this study is based around an analysis of the meaning and grammatical function of the Russian delimitative in po- and the Polish distributive in po- as prototypes in their respective semantic networks for po-. Regarding the methodological approach of this dissertation, in addition to relying on the views presented in the traditional literature, quantitative data is also presented, consisting of dictionary counts and hit counts and relative frequencies drawn from online corpora in support of the view that the delimitative is the prototype verb in po- in Russian and the distributive is the prototype verb in po- in Polish. The results of the corpus-based research show that the productivity and level of use are higher for the prototype Russian delimitative in po- relative to the Polish delimitative in po-and for the prototype Polish distributive in po- relative to the Russian distributive in po-. The main conclusion arrived upon in this study is that the meanings of the prototype verb in po- and the prototypical perfective meaning in each language overlap, which is manifested as the ability of the prototype verb in po- to function as a perfective partner in the grammar
Optimizations of Pt/SiC and W/Si multilayers for the Nuclear Spectroscopic Telescope Array
The Nuclear Spectroscopic Telescope Array, NuSTAR, is a NASA funded Small Explorer Mission, SMEX, scheduled for launch in mid 2011. The spacecraft will fly two co-aligned conical approximation Wolter-I optics with a focal length of 10 meters. The mirrors will be deposited with Pt/SiC and W/Si multilayers to provide a broad band reflectivity from 6 keV up to 78.4 keV. To optimize the mirror coating we use a Figure of Merit procedure developed for gazing incidence optics, which averages the effective area over the energy range, and combines an energy weighting function with an angular weighting function to control the shape of the desired effective area. The NuSTAR multilayers are depth graded with a power-law, d_i = a/(b + i)^c, and we optimize over the total number of bi-layers, N, c, and the maximum bi-layer thickness, d_(max). The result is a 10 mirror group design optimized for a flat even energy response both on and off-axis
Multicolor Conjugated Polymer Dots for Biological Fluorescence Imaging
Highly fluorescent conjugated polymer dots were developed for demanding applications such as fluorescence imaging in live cells. These nanoparticles exhibit small particle diameters, extraordinary fluorescence brightness, and excellent photostability. Single particle fluorescence imaging and kinetic studies indicate much higher emission rates (âŒ108 sâ1) and little or no blinking of the nanoparticles as compared to typical results for single dye molecules and quantum dots. Analysis of single particle photobleaching trajectories reveals excellent photostabilityâas many as 109 or more photons emitted per nanoparticle prior to irreversible photobleaching. The superior figures of merit of these new fluorescent probes, together with the demonstration of cellular imaging, indicate their enormous potential for demanding fluorescence-based imaging and sensing applications such as high speed super-resolution single molecule/particle tracking and highly sensitive assays
THE EFFECTS OF TWO DIFFERENT TYPES OF DYNAMIC WARM-UP AND STATIC STRETCHING ON POWER AND SPEED
Static stretching has often been found to decrease performance in power and speed activities, but dynamic warm-ups usually increase performance. We examined the effects of a mini-band warm-up, a medicine ball warm-up, and static stretching on 10m and 20m sprint times, as well as overhead medicine ball throw performance. Twenty-four Division I female soccer players completed the three warm-ups and a control 5 minute jog condition on separate days and were tested on the 10m and 20m sprint times and overhead medicine ball throw. ANOVA's and follow-up paired t-tests ( ~ ~ 0 . 0 5w)er e used to determine differences between the warm-ups. Significant differences were found between groups for the 1 Om sprint times but not for the 20m sprint times or the overhead medicine ball throw
W/SiC x-ray multilayers optimized for use above 100 keV
We have developed a new depth-graded multilayer system comprising W and SiC layers, suitable for use as hard x-ray reflective coatings operating in the energy range 100-200 keV. Grazing-incidence x-ray reflectance at E = 8 keV was used to characterize the interface widths, as well as the temporal and thermal stability in both periodic and depth-graded W/SiC structures, whereas synchrotron radiation was used to measure the hard x-ray reflectance of a depth-graded multilayer designed specifically for use in the range E ~150-170 keV. We have modeled the hard x-ray reflectance using newly derived optical constants, which we determined from reflectance versus incidence angle measurements also made using synchrotron radiation, in the range E = 120-180 keV. We describe our experimental investigation in detail, compare the new W/SiC multilayers with both W/Si and W/B4C films that have been studied previously, and discuss the significance of these results with regard to the eventual development of a hard x-ray nuclear line telescope
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Analysis of Regional Mechanics in Canine Lung Injury Using Forced Oscillations and 3D Image Registration
Acute lung injury is characterized by heterogeneity of regional mechanical properties, which is thought to be correlated with disease severity. The feasibility of using respiratory input impedance () and computed tomographic (CT) image registration for assessing parenchymal mechanical heterogeneity was evaluated. In six dogs, measurements of () before and after oleic acid injury at various distending pressures were obtained, followed by whole lung CT scans. Each () spectrum was fit with a model incorporating variable distributions of regional compliances. CT image pairs at different inflation pressures were matched using an image registration algorithm, from which distributions of regional compliances from the resulting anatomic deformation fields were computed. Under baseline conditions, average model compliance decreased with increasing inflation pressure, reflecting parenchymal stiffening. After lung injury, these average compliances decreased at each pressure, indicating derecruitment, alveolar flooding, or alterations in intrinsic tissue elastance. However, average compliance did not change as inflation pressure increased, consistent with simultaneous recruitment and strain stiffening. Image registration revealed peaked distributions of regional compliances, and that small portions of the lung might undergo relative compression during inflation. The authors conclude that assessments of lung function using () combined with the structural alterations inferred from image registration provide unique but complementary information on the mechanical derangements associated with lung injury
Earthquake Monitoring and Response from Space: The TREMOR Concept
Earthquakes and their after-effects claim thousands of lives and cause enormous property damage each year. Early warning of impending seismological events has the potential to reduce human suffering and physical damage resulting from these natural disasters. Reliable earthquake precursors have yet to be identified, but some research is currently being performed into phenomena that could be observable from space. Satellites have been unquestionably beneficial in the response to earthquakes, providing essential communication and remote sensing support. The Technological Resources for Earthquake MOnitoring and Response (TREMOR) concept was initially developed as a team project at the 2007 International Space University Summer Session Program. It recommends the establishment of an international non-governmental organization that can more efficiently co-ordinate space-based and ground-based resources for the protection of human lives and property. The TREMOR concept is explored further here, concentrating on its use of space technology to minimize the economic and human impact of earthquakes. Updated cost estimates for TREMOR satellite mission concepts are also presented
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