The Global Positioning System: Global Developments and Opportunities

International Relations/Trade,

Recent advances in our understanding of the structure and function of more unusual cation channels.

As their name implies, cation channels allow the regulated flow of cations such as sodium, potassium, calcium, and magnesium across cellular and intracellular membranes. Cation channels have long been known for their fundamental roles in controlling membrane potential and excitability in neurons and muscle. In this review, we provide an update on the recent advances in our understanding of the structure-function relationship and the physiological and pathophysiological role of cation channels. The most exciting developments in the last two years, in our opinion, have been the insights that cryoelectron microscopy has provided into the inner life and the gating of not only voltage-gated channels but also mechanosensitive and calcium- or sodium-activated channels. The mechanosensitive Piezo channels especially have delighted the field not only with a fascinating new type of structure but with important roles in blood pressure regulation and lung function

Interferometry with Synthetic Gauge Fields

We propose a compact atom interferometry scheme for measuring weak, time-dependent accelerations. Our proposal uses an ensemble of dilute trapped bosons with two internal states that couple to a synthetic gauge field with opposite charges. The trapped gauge field couples spin to momentum to allow time dependent accelerations to be continuously imparted on the internal states. We generalize this system to reduce noise and estimate the sensitivity of such a system to be S~10^-7 m / s^2 / Hz^1/2

MicroRNA detection on microsensor arrays by SPR imaging measurements with enzymatic signal enhancement.

We investigated sequence-specific and simultaneous microRNA (miRNA) detections by surface plasmon resonance (SPR) imaging measurements on SPR chips possessing an Au spot array modified with probe DNAs based on a miRNA-detection-selective SPR signal amplification method. MiRNAs were detected with the detection limit of the attomole level by SPR imaging measurements for different miRNA concentrations on a single chip. SPR signals were enhanced based on a combination process of sequence-specific hybridization of the miRNA to the probe DNAs, extension reaction of polyadenine (poly(A)) tails by poly(A) polymerase, binding of a ternary complex of T30-biotin/horseradish peroxidase (HRP)-biotin/streptavidin to the poly(A) tails, and the oxidation reaction of tetramethylbenzidine (TMB) on the HRP by providing a blue precipitate on the surface. This process sequence-specifically and dramatically amplified the SPR signals. This is a simple, cost-effective, and feasible signal amplification method based on the organic compound TMB instead of metal nanoparticles

Differential rotation of relativistic superfluid in neutron stars

It is shown how to set up a mathematically elegant and fully relativistic superfluid model that can provide a realistic approximation (neglecting small anisotropies due to crust solidity, magnetic fields, et cetera, but allowing for the regions with vortex pinning) of the global structure of a rotating neutron star, in terms of just two independently moving constituents, one of which represents the differentially rotating neutron superfluid, while the other part represents the combination of all the other ingredients, including the degenerate electrons, the superfluid protons in the core, and the ions in the crust, whose electromagnetic interactions will tend to keep them locked together in a state of approximately rigid rotation. Order of magnitude estimates are provided for relevant parameters such as the resistive drag coefficient and the maximum pinning force.Comment: 35 pages, Latex, no figure, submitted to M.N.R.A.

Meron Ground State of Rashba Spin-Orbit-Coupled Dipolar Bosons

We study the effects of dipolar interactions on a Bose-Einstein condensate with synthetically generated Rashba spin-orbit coupling. The dipolar interaction we consider includes terms that couple spin and orbital angular momentum in a way perfectly congruent with the single-particle Rashba coupling. We show that this internal spin-orbit coupling plays a crucial role in the rich ground-state phase diagram of the trapped condensate. In particular, we predict the emergence of a thermodynamically stable ground state with a meron spin configuration.Comment: 4+ pages, 3 figure

Perceptions of Shared Power, Gender Conformity, and Marital Quality in Same- and Different-Sex Marriages

Marriage is a key institutional context for the study of gender and gender inequality. One way in which gender inequality is maintained in marriage is through gender norms, which are often upheld by hegemonic masculinity—the pattern of practices that legitimize men’s dominance over women. While studies have focused on how gender conformity (i.e., women embody femininity and men embody masculinity) affects different-sex unions, they have not considered how gender conformity might shape inequalities and marital quality within same-sex unions. Marriage is a key institutional context for the study of gender and gender inequality. This research brief, led by PRC postdoctoral fellow Amanda Pollitt, examines the relationships between gender conformity (i.e., women embody femininity and men embody masculinity), perceptions of shared power, and marital quality in same- and different-sex marriages.This research was supported, in part, by Grant R21AG044585 from the National Institute on Aging (PI, Debra Umberson); Grant P2CHD042849 awarded to the Population Research Center at The University of Texas at Austin by the Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD); and Grant T32 HD007081, Training Program in Population Studies, awarded to the Population Research Center at The University of Texas at Austin by NICHD.Population Research Cente