What Does It Cost To Guarantee Returns?

The financial crisis has dramatically demonstrated how a collapse in equity prices can decimate retirement accounts. The crisis highlights the fragility of existing 401(k) plans as the only supplement to Social Security and has sparked proposals to reform the retirement income system. One component of such a system could be a new tier of retirement accounts. Given the declines in the share of earnings Social Security will replace, these accounts would bolster replacement rates for low-wage workers and increase the security of middle- and upper-wage workers who increasingly rely on their 401(k) plans to supplement Social Security. However, these new accounts could face the same risk of collapse in value seen over the past year in 401(k)s. So policymakers may find some form of guaranteed return or risk sharing desirable to prevent huge variations in outcomes. This brief explores the feasible range and the cost of the first option – guarantees...

Spin-Glass-Like Behavior in Very Dilute PdFe at Very Low Temperatures

Measurements of the electrical resistivity of palladium, residual resistivity ratio ∼22 500, containing 1.7 ppm of Fe have been made from 5.5 K to 1.8 mK. 15 Hz ac susceptibility measurements from 1 K to 1.8 mK together with the resistivity data suggest that a transition into a spin-glass state occurs near 7 mK

Bringing Agriculture into the GATT: Designing Acceptable Agricultural Policies

Agricultural and Food Policy, International Relations/Trade,

M2 macrophages exhibit higher sensitivity to oxLDL-induced lipotoxicity than other monocyte/macrophage subtypes

<p>Abstract</p> <p>Background</p> <p>In obesity, phenotypic switches occur in macrophage populations such that the predominantly M2-polarised anti-inflammatory state seen in lean individuals changes to a predominantly M1-polarised pro-inflammatory state in those who are obese. However, the mechanisms by which these phenotypic shifts occur have not yet been fully elucidated.</p> <p>Results</p> <p>The effects of oxLDL (1-40 μg/ml; 24 h) on several parameters relevant to the Unfolded Protein Response (UPR)-mediated lipotoxic effects of oxLDL (disruption of ER Ca²⁺handling; activation of the UPR transcription factor XBP-1; upregulation of the UPR target genes BiP and CHOP; apoptosis; cell viability) were investigated in human primary monocyte-derived macrophages, and also in monocyte-macrophages derived from the THP-1 monocytic cell line. A consistent pattern was observed: M2-polarised macrophages were more sensitive to the lipotoxic effects of oxLDL than either non-polarised macrophages or non-differentiated monocytic cells. Specifically, M2-polarised macrophages were the only cell type to undergo significantly increased apoptosis (Primary cells: 1.23 ± 0.01 basal; THP-1-derived: 1.97 ± 0.12 basal; <it>P </it>< 0.05 in both cases) and decreased cell viability (Primary cells: 0.79 ± 0.04 basal; THP-1-derived: 0.67 ± 0.02 basal; <it>P </it>< 0.05 in both cases) when exposed to oxLDL levels similar to those seen in overweight individuals (ie. 1 μg/ml).</p> <p>Conclusions</p> <p>We propose that the enhanced susceptibility of M2-polarised macrophages to lipotoxicity seen in the present <it>in vitro </it>study could, over time, contribute to the phenotypic shift seen in obese individuals <it>in vivo</it>. This is because a higher degree of oxLDL-induced lipotoxic cell death within M2 macrophages could contribute to a decrease in numbers of M2 cells, and thus a relative increase in proportion of non-M2 cells, within macrophage populations. Given the pro-inflammatory characteristics of a predominantly M1-polarised state, the data presented here may constitute a useful contribution to our understanding of the origin of the pro-inflammatory nature of obesity, and of the pathogenesis of obesity-associated inflammatory disorders such as Type 2 Diabetes and atherosclerosis.</p

Dependent Lung Opacity at Thin-Section CT: Evaluation by Spirometrically-Gated CT of the Influence of Lung Volume

ObjectiveTo evaluate the influence of lung volume on dependent lung opacity seen at thin-section CT.Materials and methodsIn thirteen healthy volunteers, thin-section CT scans were performed at three levels (upper, mid, and lower portion of the lung) and at different lung volumes (10, 30, 50, and 100% vital capacity), using spirometric gated CT. Using a three-point scale, two radiologists determined whether dependent opacity was present, and estimated its degree. Regional lung attenuation at a level 2 cm above the diaphragm was determined using semiautomatic segmentation, and the diameter of a branch of the right lower posterior basal segmental artery was measured at each different vital capacity.ResultsAt all three anatomic levels, dependent opacity occurred significantly more often at lower vital capacities (10, 30%) than at 100% vital capacity (p = 0.001). Visually estimated dependent opacity was significantly related to regional lung attenuation (p &lt; 0.0001), which in dependent areas progressively increased as vital capacity decreased (p &lt; 0.0001). The presence of dependent opacity and regional lung attenuation of a dependent area correlated significantly with increased diameter of a segmental arterial branch (r = 0.493 and p = 0.0002; r = 0.486 and p = 0.0003, respectively).ConclusionVisual estimation and CT measurements of dependent opacity obtained by semiautomatic segmentation are significantly influenced by lung volume and are related to vascular diameter

Magnetic Response of a Single, Isolated Gold Loop

Measurements have been made of the low-temperature magnetic response of single, isolated, micron-size Au loops. The magnetic response is found to contain a component which oscillates with the applied magnetic flux with a fundamental period of Φ0=h/e. The amplitude of the oscillatory component corresponds to a persistent current of ≃(0.3–2.0)evF/L, 1 to 2 orders of magnitude larger than predicted by current theories

Optically excited nanoscale ultrasonic transducers

In order to work at higher ultrasonic frequencies, for instance, to increase the resolution, it is necessary to fabricate smaller and higher frequency transducers. This paper presents an ultrasonic transducer capable of being made at a very small size and operated at GHz frequencies. The transducers are activated and read optically using pulsed lasers and without physical contact between the instrumentation and the transducer. This removes some of the practical impediments of traditional piezoelectric architectures (such as wiring) and allows the devices to be placed immediately on or within samples, reducing the significant effect of attenuation which is very strong at frequencies above 1 GHz. The transducers presented in this paper exploit simultaneous optical and mechanical resonances to couple the optical input into ultrasonic waves and vice versa. This paper discusses the mechanical and optical design of the devices at a modest scale (a few lm) and explores the scaling of the transducers toward the sub-micron scale. Results are presented that show how the transducers response changes depending on its local environment and how the resonant frequency shifts when the transducer is loaded by a printed protein sample