Assessing equity in health, wealth, and civic engagement: a nationally representative survey, United States, 2020

BACKGROUND

The principle of equity is fundamental to many current debates about social issues and plays an important role in community and individual health. Traditional research has focused on singular dimensions of equity (e.g., wealth), and often lacks a comprehensive perspective. The goal of this study was to assess relationships among three domains of equity, health, wealth, and civic engagement, in a nationally representative sample of U.S. residents.

METHODS

We developed a conceptual framework to guide our inquiry of equity across health, wealth, and civic engagement constructs to generate a broad but nuanced understanding of equity. Through Ipsos' KnowledgePanel service, we conducted a cross-sectional, online survey between May 29-June 20, 2020 designed to be representative of the adult U.S.

POPULATION

Based on our conceptual framework, we assessed the population-weighted prevalence of health outcomes and behaviors, as well as measures of wealth and civic engagement. We linked individual-level data with population-level environmental and social context variables. Using structural equation modeling, we developed latent constructs for wealth and civic engagement, to assess associations with a measured health variable.

RESULTS

We found that the distribution of sociodemographic, health, and wealth measures in our sample (n = 1267) were comparable to those from other national surveys. Our quantitative illustration of the relationships among the domains of health, wealth, and civic engagement provided support for the interrelationships of constructs within our conceptual model. Latent constructs for wealth and civic engagement were significantly correlated (p = 0.013), and both constructs were used to predict self-reported health. Beta coefficients for all indicators of health, wealth, and civic engagement had the expected direction (positive or negative associations).

CONCLUSION

Through development and assessment of our comprehensive equity framework, we found significant associations among key equity domains. Our conceptual framework and results can serve as a guide for future equity research, encouraging a more thorough assessment of equity.

Nanopores in solid-state membranes engineered for single molecule detection

A nanopore is an analytical tool with single molecule sensitivity. For detection, a nanopore relies on the electrical signal that develops when a molecule translocates through it. However, the detection sensitivity can be adversely affected by noise and the frequency response. Here, we report measurements of the frequency and noise performance of nanopores </=8 nm in diameter in membranes compatible with semiconductor processing. We find that both the high frequency and noise performance are compromised by parasitic capacitances. From the frequency response we extract the parameters of lumped element models motivated by the physical structure that elucidates the parasitics, and then we explore four strategies for improving the electrical performance. We reduce the parasitic membrane capacitances using: (1) thick Si(3)N(4) membranes; (2) miniaturized composite membranes consisting of Si(3)N(4) and polyimide; (3) miniaturized membranes formed from metal-oxide-semiconductor (MOS) capacitors; and (4) capacitance compensation through external circuitry, which has been used successfully for patch clamping. While capacitance compensation provides a vast improvement in the high frequency performance, mitigation of the parasitic capacitance through miniaturization offers the most promising route to high fidelity electrical discrimination of single molecules.

Small-Signal Performance and Modeling of sub-50nm nMOSFETs with f above 460-GHz

We have fabricated and tested the performance of sub-50nm gate nMOSFETs to assess their suitability for mixed signal applications in the super high frequency (SHF) band, i.e. 3-30GHz. For a 30nm×40 μm×2 device, we found f(T) =465GHz at V(ds)=2V, V(g)=0.67V, which is the highest cut-off frequency reported for a MOSFET produced on bulk silicon substrate so far. However, our measurements of f(max) and noise figure indicate that parasitics impose limitations on SHF operation. We also present a high-frequency ac model appropriate to sub-50nm gate length nanotransistors, which incorporates the effects of the parasitics. The model accurately accounts for measurements of the S and Y parameters in the frequency range from 1 to 50GHz.

Beyond the Gene Chip

We describe a prospective strategy for reading the encyclopedic information encoded in the genome: using a nanopore in a membrane formed from an MOS-capacitor to sense the charge in DNA. In principle, as DNA permeates the capacitor-membrane through the pore, the electrostatic charge distribution characteristic of the molecule should polarize the capacitor and induce a voltage on the electrodes that can be measured. Silicon nanofabrication and molecular dynamic simulations with atomic detail are technological linchpins in the development of this detector. The sub-nanometer precision available through silicon nanotechnology facilitates the fabrication of the detector, and molecular dynamics provides us with a means to design it and analyze the experimental outcomes.

The scimitar syndrome: demonstration with magnetic resonance imaging

The authors describe a case of scimitar syndrome, which is a rare congenital lung abnormality characterized by partially anomalous pulmonary venous return. MRI findings as well as other methods of diagnosis are discussed.

Changes in CNS responses to high pressure during maturation of newborn mice

From birth to maturity CD-2 mice were exposed to progressively increasing pressures of helium-oxygen. In all age groups a regular progression of changes in locomotor behavior was observed including, in sequence, increased locomotor activity and two types of convulsions designated as types I and II. The effects of altering compression rate and of reserpine pretreatment were recorded for all age groups. Maturation in these mice is associated with increased resistance to high-pressure neurological syndrome convulsions of either type, in contrast to what might have been expected from previous phylogenetic studies. The patterns in development of the two seizure types differ greatly in detail, further supporting the previously advanced inference that they represent neurological events that differ in kind rather than merely quantitatively. The effect of the results on theories that concern the mechanism of action of pressure on the vertebrate central nervous system is discussed.