Phosphorylation of protein kinase A (PKA) regulatory subunit RIα by protein kinase G (PKG) primes PKA for catalytic activity in cells.

cAMP-dependent protein kinase (PKAc) is a pivotal signaling protein in eukaryotic cells. PKAc has two well-characterized regulatory subunit proteins, RI and RII (each having α and β isoforms), which keep the PKAc catalytic subunit in a catalytically inactive state until activation by cAMP. Previous reports showed that the RIα regulatory subunit is phosphorylated by cGMP-dependent protein kinase (PKG) in vitro, whereupon phosphorylated RIα no longer inhibits PKAc at normal (1:1) stoichiometric ratios. However, the significance of this phosphorylation as a mechanism for activating type I PKA holoenzymes has not been fully explored, especially in cellular systems. In this study, we further examined the potential of RIα phosphorylation to regulate physiologically relevant "desensitization" of PKAc activity. First, the serine 101 site of RIα was validated as a target of PKGIα phosphorylation both in vitro and in cells. Analysis of a phosphomimetic substitution in RIα (S101E) showed that modification of this site increases PKAc activity in vitro and in cells, even without cAMP stimulation. Numerous techniques were used to show that although Ser101 variants of RIα can bind PKAc, the modified linker region of the S101E mutant has a significantly reduced affinity for the PKAc active site. These findings suggest that RIα phosphorylation may be a novel mechanism to circumvent the requirement of cAMP stimulus to activate type I PKA in cells. We have thus proposed a model to explain how PKG phosphorylation of RIα creates a "sensitized intermediate" state that is in effect primed to trigger PKAc activity

The Experience of Choice: Analyzing Choice Architecture on Mobile Shopping Websites

This study examines choice architecture techniques, or design techniques used to guide people toward or away from specific options, in digital choice environments. The term “nudge” has been used to describe the intentional design of choice environments; for example, product placement in stores nudges people toward more expensive items. Nudge-like choice architecture techniques are used by designers to guide decisions in digital environments. Such techniques can be designed to support and to manipulate users’ decision-making. The researcher created two sets of guidelines based on prior work with the goal of describing and delineating between (1) supportive or ethical and (2) manipulative or unethical intent in choice architecture. She used those guidelines to evaluate a sample of mobile shopping websites using a combination of document analysis and heuristic evaluation. This analysis seeks to provide insight into ethical questions inherent in design that balances organizational and end user needs.Master of Science in Information Scienc

Validation of X-ray fluorescence-measured Swine femur lead against atomic absorption spectrometry.

The aim of this study was to apply the technique of (109)Cd-based K-shell X-ray fluorescence (XRF) bone lead measurements to swine femurs and to validate the concentrations obtained therefrom against an independent chemical measurement of bone lead: atomic absorption spectrometry (AAS). The femurs ranged in lead concentration from 1.0 to 24.5 microg of lead per gram of ashed bone, as measured by AAS. On average, XRF overestimated AAS-measured femur lead by 2.6 microg/g [95% confidence interval (CI), 1.1-4.0 microg/g], approximately 2 microg/g poorer than that observed in studies of human tibiae. Measurements of swine femur and, by extension, of nonhuman bones may require adjustment of the XRF spectrum peak extraction method

X-ray Investigation of the Critical Exponent η in Argon

Measurements were made of the small-angle x-ray scattering intensity from argon near the critical point. After the scattering curves are corrected for all known effects except those resulting from irrelevant variables, a value of the critical exponent η=0.09±0.02 is obtained, while if a correction for the estimated effect of irrelevant variables is also made, η=0.03±0.03. The scattering data for argon therefore show that if irrelevant variables can be neglected, the critical exponent η for argon is in good agreement with the value obtained by Warkulwiz, Mozer, and Green from small-angle neutron scattering data for neon. These values of η, however, are clearly greater than those obtained by calculations using high-temperature expansions and renormalizationgroup techniques. On the other hand, if the effects of irrelevant variables are given by the estimate used in correcting the scattering data, the η value computed from the scattering curves agrees with the theoretical results

Incorporating lessons from high-input research into a low-margin year

Increased soybean commodity prices in recent years have generated interest in developing high-input systems to increase yield. However, little information exists about the effects of input-intensive, high-yield management on soybean yield and profitability, as well as interactions with basic agronomic practices

Nitrogen and Sulfur Fertilization in Soybean: Impact on Seed Yield and Quality

Over time, plant breeding efforts for improving soybean [Glycine max (L.) Merr.] yield was prioritized and effects on seed nutritional quality were overlooked, decreasing protein concentration. This research aims to explore the effect of nitrogen (N) and sulfur (S) fertilization on soybean seed yield, seed protein and sulfur amino acids concentration. In 2018, ten field trials were conducted across the main US soybean producing region. The treatments were fertilization at 1) planting (NSP); during 2) vegetative growth (NSV); and 3) reproductive growth (NSR) and 4) unfertilized (Control). Nitrogen fertilization was applied at the rate of 40 lb/a utilizing urea ammo­nium nitrate (UAN), and S at 9 lb/a via ammonium sulfate (AMS). A meta-analysis was performed to consider small variations among experimental designs. A summary of the effect sizes did not show effects for seed yield. However, fertilization at planting (NSP) increased seed protein by 1% more than the control across all sites. Overall, sulfur amino acid concentration increased by 1.5% relative to the control, but the most consistent benefit came from fertilization during the reproductive growth (NSR), increasing sulfur amino acids by 1.9%. Although N and S fertilization did not affect seed yields, applying N and S in different stages of the crop growth can increase protein concentration and improve protein composition, providing the opportunity to open new US soybean markets