Inverse scattering of 2d photonic structures by layer-stripping

Design and reconstruction of 2d and 3d photonic structures are usually carried out by forward simulations combined with optimization or intuition. Reconstruction by means of layer-stripping has been applied in seismic processing as well as in design and characterization of 1d photonic structures such as fiber Bragg gratings. Layer-stripping is based on causality, where the earliest scattered light is used to recover the structure layer-by-layer. Our set-up is a 2d layered nonmagnetic structure probed by plane polarized harmonic waves entering normal to the layers. It is assumed that the dielectric permittivity in each layer only varies orthogonal to the polarization. Based on obtained reflectance data covering a suitable frequency interval, time-localized pulse data are synthesized and applied to reconstruct the refractive index profile in the leftmost layer by identifying the local, time-domain Fresnel reflection at each point. Once the first layer is known, its impact on the reflectance data is stripped off, and the procedure repeated for the next layer. Through numerical simulations it will be demonstrated that it is possible to reconstruct structures consisting of several layers. The impact of evanescent modes and limited bandwidth is discussed

Structures 2 - The response of a clamped circular plate to impulsive loads

Computer analysis of clamped circular plate response to axisymmetric impulsive loa

Structures i- the response of beams and rings to high-intensity, short-duration loading

Computer programs for determining response of beams and rings to high intensity, short duration loadin

Gender Differences in Predicting Unsafe Driving Behaviors in Young Adults

Past research has uncovered personality influences on dangerous driving behavior and vehicle crashes (Furnham & Saipe, 1993; Matthews, Dorn, & Glendon, 1991). Recently, females between 16 and 20 years of age showed an increase in overall crash rate, while males within the same age group showed a decrease in overall crash rate (NHTSA, 2004; NHTSA, 2002). Adolescent and young adult females have become a critical cohort in the study of unsafe driving behavior. The purpose of this study was to examine gender differences in risky driving behavior and personality influences on these behaviors. Data presented are first year cross-sectional results in a 5-year longitudinal study. Participants were 141 male and female drivers who completed the NEO PI-R, the DDDI and a driving behavior questionnaire. In addition, the driving record of each participant was obtained from the State Department of Transportation. Females reported a higher rate of traffic violations and crashes than males. No personality traits were significantly related to crashes, but Extroversion was positively related to total traffic violations within females. The DDDI scales were not significantly related to traffic violations or vehicle crashes, but gender differences were shown within the risky driving and aggressive driving scales. Gender differences were also shown in the relationship between personality traits and DDDI scales. This data indicates that researchers and insurance companies should make an effort to consider females in their work. In addition, this study provides preliminary data on gender differences in personality as it relates to risky driving behavior

Saprolegnia diclina IIIA and S. parasitica employ different infection strategies when colonizing eggs of Atlantic salmon, Salmo salar L.

Acknowledgements The work has been funded by the European Commission through the EU Marie Curie ITN project SAPRO (238550) (MMS, AW). We would also like to acknowledge support from the BBSRC and the University of Aberdeen (PvW) and Landcatch and AquaGen for providing salmon eggs. Elin Rolen's assistance with sequencing of the strains is highly appreciated.Peer reviewedPublisher PD

On the electromagnetic properties of active media

Several results concerning active media or metamaterials are proved and discussed. In particular, we consider the permittivity, permeability, wave vector, and refractive index, and discuss stability, refraction, gain, and fundamental limitations resulting from causality

The effect of gain saturation in a gain compensated perfect lens

The transmission of evanescent waves in a gain-compensated perfect lens is discussed. In particular, the impact of gain saturation is included in the analysis, and a method for calculating the fields of such nonlinear systems is developed. Gain compensation clearly improves the resolution; however, a number of nonideal effects arise as a result of gain saturation. The resolution associated with the lens is strongly dependent on the saturation constant of the active medium.Comment: to appear in J. Opt. Soc. Am.

Medication Exposure Patterns in Primary Care Patients Prescribed Pharmacogenetically Actionable Opioids

Current approaches to assessing medication exposure fail to capture the complexity of the phenomenon and the context in which it occurs. This study’s purpose was to develop a typology of subgroups of patients who share common patterns of medication exposure. To create the typology, we used an exemplar sample of 30 patients in a large public healthcare system who had been prescribed the pharmacogenetically actionable opioids codeine or tramadol. Data related to medication exposure were drawn from large data repositories. Using a person-oriented qualitative approach, eight subgroups of patients who shared common patterns of medication exposure were identified. The subgroups had one of five opioid prescription patterns (i.e., singular, episodic, switching, sustained, multiplex), and one of three types of primary foci of medical care (i.e., pain, comorbidities, both). The findings reveal medication exposure patterns that are dynamic, multidimensional, and complex, and the typology offers an innovative approach to assessing medication exposure