Formation and tidal evolution of hot super-Earths in multiple planetary systems

Hot super-Earths are exoplanets with masses < 10 Earth masses and orbital periods < 20 days. Around 8 hot super-Earths have been discovered in the neighborhood of solar system. In this lecture, we review the mechanisms for the formation of hot super-Earths, dynamical effects that play important roles in sculpting the architecture of the multiple planetary systems. Two example systems (HD 40307 and GJ 436) are presented to show the formation and evolution of hot super-Earths or Neptunes.Comment: 12 pages, 4 color figures, Lecture in 'Extrasolar planets in Multi-Body systems: Theory and Observation',Torun (Poland), August 25-29, 2008, to appear in European Astronomical Society Publication Serie

Gendered aspects of perceived and internalized HIV-related stigma in China.

Although studies have demonstrated that females experience more HIV-related stigma than males do, questions remain regarding the different dimensions of the stigma (i.e., perceived versus internalized) in China. The present study investigated gender differences in perceived and internalized HIV-related stigma, taking into account the potential influence of education. The study was conducted between October 2011 and March 2013. A total of 522 people living with HIV (PLH) were recruited from Anhui Province, China. The PLH participated in a survey using the Computer Assisted Personal Interview (CAPI) method. The gender differences in perceived and internalized HIV-related stigma were calculated with and without stratifying by education level. Female participants had significantly less education than the male participants. No significant difference was observed between females and males with respect to perceived stigma. However, females reported significantly higher internalized stigma than males did (p &lt; .001). When socio-demographic characteristics were controlled, the gender difference in internalized stigma remained significant among educated participants (p = .038). The findings suggested that gender differences in HIV-related stigma were primarily found for internalized stigma. Heightened intervention efforts are encouraged to reduce internalized HIV-related stigma, particularly among female PLH in China and other regions with similar gender dynamics

The silicate model and carbon rich model of CoRoT-7b, Kepler-9d and Kepler-10b

Possible bulk compositions of the super-Earth exoplanets, CoRoT-7b, Kepler-9d, and Kepler-10b are investigated by applying a commonly used silicate and a non-standard carbon model. Their internal structures are deduced using the suitable equation of state of the materials. The degeneracy problems of their compositions can be partly overcome, based on the fact that all three planets are extremely close to their host stars. By analyzing the numerical results, we conclude: 1) The iron core of CoRoT-7b is not more than 27% of its total mass within 1 $\sigma$ mass-radius error bars, so an Earth-like composition is less likely, but its carbon rich model can be compatible with an Earth-like core/mantle mass fraction; 2) Kepler-10b is more likely with a Mercury-like composition, its old age implies that its high iron content may be a result of strong solar wind or giant impact; 3) the transiting-only super-Earth Kepler-9d is also discussed. Combining its possible composition with the formation theory, we can place some constraints on its mass and bulk composition.Comment: 20 pages, 8figures, accepted for publication in RAA. arXiv admin note: text overlap with arXiv:0707.289

GreenVis: Energy-Saving Color Schemes for Sequential Data Visualization on OLED Displays

The organic light emitting diode (OLED) display has recently become popular in the consumer electronics market. Compared with current LCD display technology, OLED is an emerging display technology that emits light by the pixels themselves and doesn’t need an external back light as the illumination source. In this paper, we offer an approach to reduce power consumption on OLED displays for sequential data visualization. First, we create a multi-objective optimization approach to find the most energy-saving color scheme for given visual perception difference levels. Second, we apply the model in two situations: pre-designed color schemes and auto generated color schemes. Third, our experiment results show that the energy-saving sequential color scheme can reduce power consumption by 17.2% for pre-designed color schemes. For auto-generated color schemes, it can save 21.9% of energy in comparison to the reference color scheme for sequential data

The effect of planet-planet scattering on the survival of exomoons

Compared to the giant planets in the solar system, exoplanets have many remarkable properties such as the prevalence of giant planets on eccentric orbits and the presence of hot Jupiters. Planet-planet scattering (PPS) between giant planets is a possible mechanism in interpreting above and other observed properties. If the observed giant planet architectures are indeed the outcomes of PPS, such drastic dynamical process must affect their primordial moon systems. In this Letter, we discuss the effect of the PPS on the survival of their regular moons. From the viewpoint of observations, some preliminary conclusions are drawn from the simulations. 1. PPS is a destructive process to the moon systems, single planets on eccentric orbits are not the ideal moon-search targets. 2. If hot Jupiters formed through PPS, their original moons have little chance to survive. 3. Planets in multiple systems with small eccentricities are more likely holding their primordial moons. 4. Compared to the lower-mass planets, the massive ones in multiple systems may not be the preferred moon-search targets if the system underwent a PPS history.Comment: published at ApJ