Cepheid Variables in the Maser-Host Galaxy NGC 4258

We present results of a ground-based survey for Cepheid variables in NGC 4258. This galaxy plays a key role in the Extragalactic Distance Scale due to its very precise and accurate distance determination via VLBI observations of water masers. We imaged two fields within this galaxy using the Gemini North telescope and GMOS, obtaining 16 epochs of data in the SDSS gri bands over 4 years. We carried out PSF photometry and detected 94 Cepheids with periods between 7 and 127 days, as well as an additional 215 variables which may be Cepheids or Population II pulsators. We used the Cepheid sample to test the absolute calibration of theoretical gri Period-Luminosity relations and found good agreement with the maser distance to this galaxy. The expected data products from the Large Synoptic Survey Telescope (LSST) should enable Cepheid searches out to at least 10 Mpc.Comment: Accepted for publication in the Astronomical Journa

Distinguishing the opponents in the prisoner dilemma in well-mixed populations

Here we study the effects of adopting different strategies against different opponent instead of adopting the same strategy against all of them in the prisoner dilemma structured in well-mixed populations. We consider an evolutionary process in which strategies that provide reproductive success are imitated and players replace one of their worst interactions by the new one. We set individuals in a well-mixed population so that network reciprocity effect is excluded and we analyze both synchronous and asynchronous updates. As a consequence of the replacement rule, we show that mutual cooperation is never destroyed and the initial fraction of mutual cooperation is a lower bound for the level of cooperation. We show by simulation and mean-field analysis that for synchronous update cooperation dominates while for asynchronous update only cooperations associated to the initial mutual cooperations are maintained. As a side effect of the replacement rule, an "implicit punishment" mechanism comes up in a way that exploitations are always neutralized providing evolutionary stability for cooperation

Force of Beauty or Object of Desire? The Priming Effects of Makeup Video Advertisements on Self-Objectification in College Women

Women are too often valued for their beauty and have shifted their focus from character to body improvement (Brumberg, 1998). Objectification theory (Frederickson & Roberts, 1997) posits that sexual objectification socializes females to evaluate themselves based on looks. Self-objectification is the attempt to control this external perception by monitoring one’s physical appearance. Women are more likely to think “How do I look?” than “What am I capable of?” The priming effects of positive and negative body-focused makeup advertisements on college-aged women’s level of self-objectification were examined in two separate studies. In study one, 87 participants viewing positive vs. negative advertisements reported more traits and abilities; this was especially true for high self-objectifiers. Participants viewing positive advertisements reported more positive emotions, suggesting the salutary role that positive messaging may play. Results were replicated in study two, with 172 participants who viewed positive vs. negative advertisements reporting significantly fewer body shape statements, more trait and abilities, as well as more physical competence statements. In addition, individuals who viewed advertisements with non-objectifying content responded with a significantly greater number of positively valenced statements and significantly fewer negative statements about themselves in comparison to women who viewed objectifying advertisements. These results suggest that marketers should eschew advertising that sexually objectifies women and promotes unattainable beauty goals. Future research should evaluate cumulative and long-term effects of advertisement and examine whether exposure that leads to lower levels of objectification also minimizes negative consequences associated with objectifying media influences (e.g., body shame, depression, eating disorder)

Organizational readiness for wellness promotion - a survey of 100 African American church leaders in South Los Angeles.

BackgroundChurches are an important asset and a trusted resource in the African American community. We needed a better understanding of their readiness to engage in health promotion before launching a large-scale health promotion effort in partnership with South Los Angeles churches.MethodsIn 2017, we conducted surveys with leaders of 100 churches. Surveys were conducted face-to-face (32%) or by telephone (68%) with senior pastors (one per church) and lasted on average 48 min. We compared small (less than 50 active members), medium (50-99 active members) and large churches (at least 100 active members), and assessed which church characteristics were associated with the implementation of wellness activities.ResultsMedium and large churches conducted significantly more wellness activities than small churches and were more likely to have wellness champions and health policies. Regardless of church size, insufficient budget was the most commonly cited barrier to implement wellness activities (85%). A substantial proportion of churches was not sure how to implement wellness activities (61%) and lacked volunteers (58%). Forty-five percent of the variation in the number of wellness activities in the last 12 months was explained by church characteristics, such as size of congregation, number of paid staff, leadership engagement, having a wellness ministry and barriers.ConclusionsMany churches in South Los Angeles are actively engaged in health promotion activities, despite a general lack of resources. We recommend a comprehensive assessment of church characteristics in intervention studies to enable the use of strategies (e.g., stratification by size) that reduce imbalances that could mask or magnify study outcomes. Our data provide empirical support for the inner settings construct of the Consolidated Framework for Implementation Research in the context of health promotion in African American churches

Magnetic and vibrational properties of high-entropy alloys

The magnetic properties of high-entropy alloys based on equimolar FeCoCrNi were investigated using vibrating sample magnetometry to determine their usefulness in high-temperature magnetic applications. Nuclear resonant inelastic x-ray scattering measurements were performed to evaluate the vibrational entropy of the ^(57)Fe atoms and to infer chemical order. The configurational and vibrational entropy of alloying are discussed as they apply to these high-entropy alloys

A Submillimeter HCN Laser in IRC+10216

We report the detection of a strong submillimeter wavelength HCN laser line at a frequency near 805 GHz toward the carbon star IRC+10216. This line, the J=9-8 rotational transition within the (04(0)0) vibrationally excited state, is one of a series of HCN laser lines that were first detected in the laboratory in the early days of laser spectroscopy. Since its lower energy level is 4200 K above the ground state, the laser emission must arise from the inner part of IRC+10216's circumstellar envelope. To better characterize this environment, we observed other, thermally emitting, vibrationally excited HCN lines and find that they, like the laser line, arise in a region of temperature approximately 1000 K that is located within the dust formation radius; this conclusion is supported by the linewidth of the laser. The (04(0)0), J=9-8 laser might be chemically pumped and may be the only known laser (or maser) that is excited both in the laboratory and in space by a similar mechanism.Comment: 11 pages, 3 figure