Research Brief: The Role of Tasks and Skills in Explaining the Disability Pay Gap

A disparity in pay exists between workers with and without disabilities. This gap persists even in analyses that control for a variety of factors and incorporate compensation benefits other than wages and salaries. To better understand the underlying sources of these differences, occupation-level data on employee skill and task requirements are considered. Evaluating the earnings gap with this additional information provides insights regarding the economic returns to certain workplace tasks and skills that may contribute to the earnings gap that we observe for people with disabilities

Magnetization transfer magnetic resonance of human atherosclerotic plaques ex vivo detects areas of high protein density

<p>Abstract</p> <p>Background</p> <p>Proteins are major plaque components, and their degradation is related to the plaque instability. We sought to assess the feasibility of magnetization transfer (MT) magnetic resonance (MR) for identifying fibrin and collagen in carotid atherosclerotic plaques <it>ex vivo</it>.</p> <p>Methods</p> <p>Human carotid artery specimens (n = 34) were obtained after resection from patients undergoing endarterectomy. MR was completed within 12 hr after surgery on an 11.7T MR microscope prior to fixation. Two sets of T1W spoiled gradient echo images were acquired with and without the application of a saturation pulse set to 10 kHz off resonance. The magnetization transfer ratio (MTR) was calculated, and the degree of MT contrast was correlated with histology.</p> <p>Results</p> <p>MT with appropriate calibration clearly detected regions with high protein density, which showed a higher MTR (thick fibers (collagen type I) (54 ± 8%)) compared to regions with a low amount of protein including lipid (46 ± 8%) (p = 0.05), thin fibers (collagen type III) (11 ± 6%) (p = 0.03), and calcification (6.8 ± 4%) (p = 0.02). Intraplaque hemorrhage (IPH) with different protein density demonstrated different MT effects. Old (rich in protein debris) and recent IPH (rich in fibrin) had a much higher MTR 69 ± 6% and 55 ± 9%, respectively, compared to fresh IPH (rich in intact red blood cells)(9 ± 3%).</p> <p>Conclusions</p> <p>MT MR enhances plaque tissue contrast and identifies the protein-rich regions of carotid artery specimens. The additional information from MTR of IPH may provide important insight into the role of IPH on plaque stability, evolution, and the risk for future ischemic events.</p

Research Brief: Total Compensation Gaps are Distinct from Wage Gaps

While the disparity in wage and salary income between workers with and without disabilities is well documented in the literature, less is known about the gap in total compensation. Health insurance, mandated benefits, and days of leave for vacation or illness are examples of the additional forms of compensation that comprise roughly 30 percent of total hourly compensation costs by firms for workers

Private Computation of Polynomials over Networks

This study concentrates on preserving privacy in a network of agents where each agent seeks to evaluate a general polynomial function over the private values of her immediate neighbors. We provide an algorithm for the exact evaluation of such functions while preserving privacy of the involved agents. The solution is based on a reformulation of polynomials and adoption of two cryptographic primitives: Paillier as a Partially Homomorphic Encryption scheme and multiplicative-additive secret sharing. The provided algorithm is fully distributed, lightweight in communication, robust to dropout of agents, and can accommodate a wide class of functions. Moreover, system theoretic and secure multi-party conditions guaranteeing the privacy preservation of an agent's private values against a set of colluding agents are established. The theoretical developments are complemented by numerical investigations illustrating the accuracy of the algorithm and the resulting computational cost.Comment: 11 pages, 2 figure

Hidden spin-current conservation in 2d Fermi liquids

We report the existence of regimes of the two dimensional Fermi liquid that show unusual conservation of the spin current and may be tuned by varying some parameter like the density of fermions. We show that for reasonable models of the effective interaction the spin current may be conserved in general in 2d, not only for a particular regime. Low temperature spin waves propagate distinctively in these regimes and entirely new ``spin-acoustic'' modes are predicted for scattering-dominated temperature ranges. These new high-temperature propagating spin waves provide a clear signature for the experimental search of such regimes.Comment: 4 pages, no figures, revised version, accepted for pub. in the PR

Is the meiofauna a good indicator for climate change and anthropogenic impacts?

Our planet is changing, and one of the most pressing challenges facing the scientific community revolves around understanding how ecological communities respond to global changes. From coastal to deep-sea ecosystems, ecologists are exploring new areas of research to find model organisms that help predict the future of life on our planet. Among the different categories of organisms, meiofauna offer several advantages for the study of marine benthic ecosystems. This paper reviews the advances in the study of meiofauna with regard to climate change and anthropogenic impacts. Four taxonomic groups are valuable for predicting global changes: foraminifers (especially calcareous forms), nematodes, copepods and ostracods. Environmental variables are fundamental in the interpretation of meiofaunal patterns and multistressor experiments are more informative than single stressor ones, revealing complex ecological and biological interactions. Global change has a general negative effect on meiofauna, with important consequences on benthic food webs. However, some meiofaunal species can be favoured by the extreme conditions induced by global change, as they can exhibit remarkable physiological adaptations. This review highlights the need to incorporate studies on taxonomy, genetics and function of meiofaunal taxa into global change impact research

MSI-78, an Analogue of the Magainin Antimicrobial Peptides, Disrupts Lipid Bilayer Structure via Positive Curvature Strain

In this work, we present the first characterization of the cell lysing mechanism of MSI-78, an antimicrobial peptide. MSI-78 is an amphipathic α-helical peptide designed by Genaera Corporation as a synthetic analog to peptides from the magainin family. (31)P-NMR of mechanically aligned samples and differential scanning calorimetry (DSC) were used to study peptide-containing lipid bilayers. DSC showed that MSI-78 increased the fluid lamellar to inverted hexagonal phase transition temperature of 1,2-dipalmitoleoyl-phosphatidylethanolamine indicating the peptide induces positive curvature strain in lipid bilayers. (31)P-NMR of lipid bilayers composed of MSI-78 and 1-palmitoyl-2-oleoyl-phosphatidylethanolamine demonstrated that the peptide inhibited the fluid lamellar to inverted hexagonal phase transition of 1-palmitoyl-2-oleoyl-phosphatidylethanolamine, supporting the DSC results, and the peptide did not induce the formation of nonlamellar phases, even at very high peptide concentrations (15 mol %). (31)P-NMR of samples containing 1-palmitoyl-2-oleoyl-phosphatidylcholine and MSI-78 revealed that MSI-78 induces significant changes in the bilayer structure, particularly at high peptide concentrations. At lower concentrations (1–5%), the peptide altered the morphology of the bilayer in a way consistent with the formation of a toroidal pore. Higher concentrations of peptide (10–15%) led to the formation of a mixture of normal hexagonal phase and lamellar phase lipids. This work shows that MSI-78 induces significant changes in lipid bilayers via positive curvature strain and presents a model consistent with both the observed spectral changes and previously published work

The effects of librations on the 13C13C chemical shift and 2H2H electric field gradient tensors in β-calcium formate

The magnitudes and orientations of the principal elements of the 13C13C chemical shift anisotropy (CSA) tensor in the molecular frame of the formate ion in β-calcium formate is determined using one-dimensional dipolar-shift spectroscopy. The magnitudes of the principal elements of the 13C CSA13CCSA tensor are σ11C = 104 ppm,σ11C=104ppm, σ22C = 179 ppm,σ22C=179ppm, and σ33C = 233 ppm.σ33C=233ppm. The least shielding element of the 13C CSA13CCSA tensor, σ33C,σ33C, is found to be collinear with the C–H bond. The temperature dependence of the 13C CSA13CCSA and the 2H2H quadrupole coupling tensors in β-calcium formate are analyzed for a wide range of temperature (173–373 K). It was found that the span of the 13C CSA13CCSA and the magnitude of the 2H2H quadrupole coupling interactions are averaged with the increasing temperature. The experimental results also show that the 2H2H quadrupole coupling tensor becomes more asymmetric with increasing temperature. A librational motion about the σ22Cσ22C axis of the 13C CSA13CCSA tensor is used to model the temperature dependence of the 13C CSA13CCSA tensor. The temperature dependence of the mean-square amplitude of the librational motion is found to be 〈α2〉 = 2.6×10−4(T) rad2〈α2〉=2.6×10−4(T)rad2 K−1.K−1. The same librational motion also accounts for the temperature-dependence of the 2H2H quadrupole coupling tensor after the relative orientation of the 13C CSA13CCSA and 2H2H electric field gradient tensors are taken into account. Reconsideration of the results of a previous study found that the librational motion, not the vibrational motion, accounts for an asymmetry in the 1H–13C1H–13C dipolar coupling tensor of α-calcium formate at room temperature. © 2000 American Institute of Physics.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/71312/2/JCPSA6-113-24-11187-1.pd