The Frames Behind the Games: Player's Perceptions of Prisoner's Dilemma, Chicken, Dictator, and Ultimatum Games

The tension between cooperative and competitive impulses is an eternal issue for every society. But how is this problem perceived by individual participants in the context of a behavioral games experiment? We first assess individual differences in players’ propensity to cooperate in a series of experimental games. We then use openended interviews with a subset of those players to investigate the various concepts (or ‘frames’) they used when thinking about self-interested and cooperative actions. More generally, we hope to raise awareness of player’s perceptions of experimental environments to inform both the design and interpretation of experiments and experimental data.Laboratory Experiment, Frames, Selfishness, Cooperation

Developing a Yeast Model of Amyotrophic Lateral Sclerosis Involving the SOD1 Gene

Amyotrophic lateral sclerosis (ALS), one of the most common neuromuscular diseases in the world, is an unremittingly progressive disease that degenerates motor neurons in the brain and spinal cord. Roughly 10% of ALS cases are considered familial and can result from mutations in more than dozen different genes. The most common mutations in familial ALS occur in the SOD1 gene. SOD1 encodes a copper-zinc superoxide dismutase that detoxifies oxygen free radicals.  To date, approximately 140 mutations in SOD1 (many of which are missense) have been linked to familial ALS.  Evidence suggests that these mutations induce SOD1 protein misfolding and aggregation into cytotoxic structures.  We are developing a yeast model of ALS based on the expression of mutant human SOD1 proteins.  Such a yeast system will permit high throughput genetic screens to identify genes that enhance or suppress the toxic phenotypes associated with mutant SOD1 expression (thereby identifying critical supporting or suppressing pathways), as well as chemical screens to identify compounds that inhibit mutant SOD1 toxicit

BH3I-1 DERIVATIVES INHIBIT THE FILAMENTOUS GROWTH OF THE CEA10 STRAIN OF ASPERGILLUS FUMIGATUS

Recent and exciting advances in medical therapies for cancer and organ failures have greatly extended the life span of afflicted patients. However, these therapies often place the patient at risk for potentially lethal fungal infections. As the number of immunocompromised patients continues to rise, there has been an increase in associated opportunistic fungal infections. Treatment options for invasive mycoses caused by Candida albicans and Aspergillus fumigatus are surprisingly limited. A. fumigatus is the most common Aspergillus species associated with invasive pulmonary aspergillosis, accounting for over 60% of cases. Aspergillus grows as a filamentous mold with true hyphae originating from the germination of asexual conidia.  A. fumigatus is not a dimorphic fungi as is the case with C. albicans, however, as both grow in hyphal form it seems possible that small molecules that inhibit the transition of C. albicans budded cells to hyphal growth (often referred to as the germination of blastoconidia) may also inhibit the germination of Aspergillus conidia. We tested BH3I-1 and derivatives against A. fumigatus strain CEA10 in YPD media. BH3I-1 and five of the derivatives inhibited at a 200?M concentration based on general observation via microscopy as well as eleven showing promising inhibition at possible different concentrations. Out of these inhibiting molecules, seven also shown inhibition within the prior C. albicans assay. We are currently employing a micro-plate reader to obtain quantitative levels of inhibition with increasing concentrations of molecule. Molecule 54 at the 300?M concentration showed similar inhibition to that of BH3I-1 at the same concentration

IDENTIFICATION OF POTENTIAL TARGETS OF THE GRR1P SCF UBIQUITIN LIGASE IN FUNGI

The opportunistic human pathogen Candida albicans causes both superficial and life-threatening systemic infections and is a leading cause of fungal disease in immunocompromised individuals.  C. albicans can grow in different cell shapes, or morphologies, including yeast-like cells and a variety of filamentous forms, such as true hyphae and pseudohyphae.   Yeast, hyphae and pseudohyphae have been observed at the sites of Candida infection and there is strong evidence that morphogenesis, the transition between yeast and filamentous growth forms, is essential for virulence. Several studies have implicated ubiquitin-dependent proteolysis in the regulation of morphogenesis, yet the mechanism by which this pathway does so is largely unknown.  Previously, we have shown that deletion of the GRR1 gene results in the constitutive formation of filamentous growth forms.  The Grr1 protein is a component of an SCF ubiquitin ligase system that selectively targets proteins for degradation.  Thus, the loss of Grr1-mediated proteolysis presumably leads to the aberrant accumulation, and inappropriate activity, of a protein or proteins that induce filamentous growth.  The spectrum of proteins targeted for degradation by Grr1 is not known.  The goal of this project is to identify Grr1 targets in Saccharomyces cerevisiae, an experimentally tractable model system for pathogenic fungi.  We are using a novel proteomics-based approach to isolate and characterize proteins that are ubiquitinated in a Grr1-dependent fashion. The successful identification of Grr1p targets will be important for developing a working model of the pathways involved in the yeast to filamentous growth transition in pathogenic fungi

Post-denial Strategies: How to Get from No to Yes

U.S. Citizenship and Immigration Services (USCIS) seems to be denying more petitions than ever these days. Cases that were solid approvals a few years ago now are receiving denials, even though the law and regulations have not changed. But don’t give up hope. Opportunities exist to overcome denials. This practice advisory focuses on post-denial strategies for petitions filed with USCIS, not strategies in immigration court. The article discusses motions to reopen, motions for reconsideration, appeals to the USCIS Administrative Appeals Office (AAO), and litigation. This practice advisory also discusses when filing a new petition may be a better option, and how the beneficiary’s status, including unlawful presence, may affect the options

Post-denial Strategies: How to Get from No to Yes

U.S. Citizenship and Immigration Services (USCIS) seems to be denying more petitions than ever these days. Cases that were solid approvals a few years ago now are receiving denials, even though the law and regulations have not changed. But don’t give up hope. Opportunities exist to overcome denials. This practice advisory focuses on post-denial strategies for petitions filed with USCIS, not strategies in immigration court. The article discusses motions to reopen, motions for reconsideration, appeals to the USCIS Administrative Appeals Office (AAO), and litigation. This practice advisory also discusses when filing a new petition may be a better option, and how the beneficiary’s status, including unlawful presence, may affect the options

Probable detection of starlight reflected from the giant exoplanet orbiting tau Bootis

Giant planets orbiting stars other than the Sun are clearly detectable through precise radial-velocity measurements of the orbital reflex motion of the parent star. In the four years since the discovery of the companion to the star 51 Peg, similar low-amplitude ``Doppler star wobbles'' have revealed the presence of some 20 planets orbiting nearby solar-type stars. Several of these newly-discovered planets are very close to their parent stars, in orbits with periods of only a few days. Being an indirect technique, however, the reflex-velocity method has little to say about the sizes or compositions of the planets, and can only place lower limits on their masses. Here we report the use of high-resolution optical spectroscopy to achieve a probable detection of the Doppler-shifted signature of starlight reflected from one of these objects, the giant exoplanet orbiting the star tau Bootis. Our data give the planet's orbital inclination i=29 degrees, indicating that its mass is some 8 times that of Jupiter, and suggest strongly that the planet has the size and reflectivity expected for a gas-giant planet.Comment: 15 pages, 4 figures. (Fig 1 and equation for epsilon on p1 para 2 revised; changed from double to single spacing

Results from Solar Reflective Band End-to-End Testing for VIIRS F1 Sensor Using T-SIRCUS

Verification of the Visible Infrared Imager Radiometer Suite (VIIRS) End-to-End (E2E) sensor calibration is highly recommended before launch, to identify any anomalies and to improve our understanding of the sensor on-orbit calibration performance. E2E testing of the Reflective Solar Bands (RSB) calibration cycle was performed pre-launch for the VIIRS Fight 1 (F1) sensor at the Ball Aerospace facility in Boulder CO in March 2010. VIIRS reflective band calibration cycle is very similar to heritage sensor MODIS in that solar illumination, via a diffuser, is used to correct for temporal variations in the instrument responsivity. Monochromatic light from the NIST T-SIRCUS was used to illuminate both the Earth View (EV), via an integrating sphere, and the Solar Diffuser (SD) view, through a collimator. The collimator illumination was cycled through a series of angles intended to simulate the range of possible angles for which solar radiation will be incident on the solar attenuation screen on-orbit. Ideally, the measured instrument responsivity (defined here as the ratio of the detector response to the at-sensor radiance) should be the same whether the EV or SD view is illuminated. The ratio of the measured responsivities was determined at each collimator angle and wavelength. In addition, the Solar Diffuser Stability Monitor (SDSM), a ratioing radiometer designed to track the temporal variation in the SD BRF by direct comparison to solar radiation, was illuminated by the collimator. The measured SDSM ratio was compared to the predicted ratio. An uncertainty analysis was also performed on both the SD and SDSM calibrations