Variations on the balloon analogue risk task: A censored regression analysis.

In the present project, we reexamined the balloon analogue risk task (BART) by evaluating three variations on the task: one that does not require pumping, one that controls for trial duration, and another that withholds feedback on popping until the end of each trial. To accurately assess the censored data produced by the BART, performance was compared across these variations using Bayesian analysis with censored regression. The first experiment compared a task that required pumping to one that did not, and revealed that the tendency to respond earlier than is optimal does not reflect an avoidance of effort.

The temporal dynamics of waiting when reward is increasing.

The temporal dynamics of waiting are complex. The present study used a video game involving contingencies that produced differential reinforcement of wait times by arranging for the magnitude of the reward to be related to the duration of each inter-response time. In previous research, when outcomes were gradually increasing in value from a minimum to a maximum, two modes of behavior are observed: waiting as little as possible before cashing in (i.

Optimal go/no-go ratios to maximize false alarms.

Despite the ubiquity of go/no-go tasks in the study of behavioral inhibition, there is a lack of evidence regarding the impact of key design characteristics, including the go/no-go ratio, intertrial interval, and number of types of go stimuli, on the production of different response classes of central interest. In the present study we sought to empirically determine the optimal conditions to maximize the production of a rare outcome of considerable interest to researchers: false alarms. As predicted, the shortest intertrial intervals (450 ms), intermediate go/no-go ratios (2:1 to 4:1), and the use of multiple types of go stimuli produced the greatest numbers of false alarms.

Hot under the collar: The impact of heat on game play.

High temperatures have been documented to affect behavior in a variety of ways depending on the nature of the task. We extended this prior research by examining the effects of dynamically changing temperature on various aspects of performance in a video game task. In the span of approximately an hour, temperature was gradually increased, stayed constant for a period of time, and gradually decreased to baseline.

Pulsed-Plasma Physical Vapor Deposition Approach Toward the Facile Synthesis of Multilayer and Monolayer Graphene for Anticoagulation Applications.

We demonstrate the growth of multilayer and single-layer graphene on copper foil using bipolar pulsed direct current (DC) magnetron sputtering of a graphite target in pure argon atmosphere. Single-layer graphene (SG) and few-layer graphene (FLG) films are deposited at temperatures ranging from 700 °C to 920 °C within <30 min. We find that the deposition and post-deposition annealing temperatures influence the layer thickness and quality of the graphene films formed.

In Situ XPS Chemical Analysis of MnSiO3 Copper Diffusion Barrier Layer Formation and Simultaneous Fabrication of Metal Oxide Semiconductor Electrical Test MOS Structures.

Copper/SiO2/Si metal-oxide-semiconductor (MOS) devices both with and without a MnSiO3 barrier layer at the Cu/SiO2 interface have been fabricated in an ultrahigh vacuum X-ray photoelectron spectroscopy (XPS) system, which allows interface chemical characterization of the barrier formation process to be directly correlated with electrical testing of barrier layer effectiveness. Capacitance voltage (CV) analysis, before and after tube furnace anneals of the fabricated MOS structures showed that the presence of the MnSiO3 barrier layer significantly improved electric stability of the device structures. Evidence of improved adhesion of the deposited copper layer to the MnSiO3 surface compared to the clean SiO2 surface was apparent both from tape tests and while probing the samples during electrical testing.

Sodium butyrate stimulates NHE8 expression via its role on activating NHE8 basal promoter activity.

Butyrate is a major metabolite in colonic lumen. It is produced from bacterial fermentation of dietary fiber. Butyrate has been shown to stimulate electroneutral sodium absorption through its regulation on sodium/hydrogen exchanger 3 (NHE3).

A delay discounting task produces a greater likelihood of waiting than a deferred gratification task.

A first-person-shooter video game was adapted for the study of choice between smaller sooner and larger later outcomes to compare the behavioral patterns produced by deferred gratification (DG) and delay discounting (DD) tasks. Participants played a game in which they could either fire their weapon sooner and do a small amount of damage or wait a few seconds to fire their weapon and do a larger amount of damage. For the DD task, a failure to fire within one second committed the player to waiting for the larger later outcome thus removing the opportunity to defect during the delay that is present in the DG task.

Outcome probability versus magnitude: when waiting benefits one at the cost of the other.

Using a continuous impulsivity and risk platform (CIRP) that was constructed using a video game engine, choice was assessed under conditions in which waiting produced a continuously increasing probability of an outcome with a continuously decreasing magnitude (Experiment 1) or a continuously increasing magnitude of an outcome with a continuously decreasing probability (Experiment 2). Performance in both experiments reflected a greater desire for a higher probability even though the corresponding wait times produced substantive decreases in overall performance. These tendencies are considered to principally reflect hyperbolic discounting of probability, power discounting of magnitude, and the mathematical consequences of different response rates.

Altered residues in key proteins influence the expression and activity of the nitrogenase complex in an adaptive CO2 fixation-deficient mutant strain of Rhodobacter sphaeroides.

Previously, the RubisCO-compromised spontaneous adaptive Rhodobacter sphaeroides mutant, strain 16PHC, was shown to derepress the expression of genes that encode the nitrogenase complex under normal repressive conditions. As a result of this adaptation, the active nitrogenase complex restored redox balance, thus allowing strain 16PHC to grow under photoheterotrophic conditions in the absence of an exogenous electron acceptor. A combination of whole genome pyrosequencing and whole genome microarray analyses was employed to identify possible loci responsible for the observed phenotype.