Search For Gas Giants Around Late-m Dwarfs

We carried out a near-infrared radial velocity search for Jupiter-mass planets around 36 late M dwarfs. This survey was the first of its kind undertaken to monitor radial velocity variability of these faint dwarfs. For this unique survey we employed the 10-m Keck II on Mauna Kea in Hawaii. With a resolution of 20,000 on the near-infrared spectrograph, NIRSPEC, we monitored these stars over four epochs in 2007. In addition to the measurement of relative radial velocity we established physical properties of these stars. The physical properties of M dwarfs we determined included the identification of neutral atomic lines, the measurement of pseudo-equivalent widths, masses, surface gravity, effective temperature, absolute radial velocities, rotational velocities and rotation periods. The identification of neutral atomic lines was carried out using the Vienna Atomic line Database. We were able to confirm these lines that were previously identified. We also found that some of the lines observed in the K-type stars, such as Mg I though weak, still persist in late M dwarfs. Using the measurement of pseudo-equivalent widths (p-EW) of 13 neutral atomic lines, we have established relations between p-EW and spectral type. Such relations serve as a tool in determining the spectral type of an unknown dwarf star by means of measuring its p-EW. We employed the mass-luminosity relation to compute the masses of M dwarfs. Our calculations indicate these dwarfs to be in the range of 0.1 to 0.07 solar masses. This suggests that some of the late M dwarfs appear to be in the Brown dwarf regime. Assuming their radii of 0.1 solar radii, we calculated their surface gravity. The mean surface gravity is, log g = 5.38. Finally their effective temperature was determined by using the spectral-type iii temperature relationship. Our calculations show effective temperatures in the range of 3000 2300 K. Comparison of these values with models in literature show a good agreement. The absolute radial and rotational velocities of our targets were also calculated. Values of rotational velocities indicate that M dwarfs are, in general, slow rotators. Using our result and that from literature, we extended our study of rotational velocities to L dwarfs. Our observations show an increase in rotational velocities from late M to L dwarfs. We also find that the mean periods of M dwarfs are less than 10 hours. In order to improve our precision in measuring relative radial velocity (RV), we employed the use of deconvolution method. With this method we were able to ameliorate relative RV precision from 300 m/s to 200 m/s. This was a substantial improvement in our ability to detect gas-giant planets. However none of the 15 dwarfs we monitored indicate a presence of companions. This null result was then used to compute the upper limit to the binary frequency and close-in Jupiter mass planetary frequency. We find the binary frequency to be 11% while the planetary frequency was 1.20%

Common fixed point theorems for finite number of mappings in symmetric spaces

In this paper, we prove a common fixed theorem for ten mappings on symmetric spaces. We extend our result for finite number of mappings. The mappings involved in our results are noncompatible and discontinuous. We extend and generalize several earlier results.Publisher's Versio

Should I stay or should I go? Mood congruity, self-monitoring and retail context preference

This article extends the discussion of congruity 1) by examining the effect in a retail context and, 2) by considering the moderating role of self-monitoring on congruity. Two experiments found that when low self-monitors imagine a context that differs in valence from their mood, they feel more distinctive from the environment and, in turn, prefer contexts that are congruent with their mood. High self-monitors on the other hand prefer a context that differs in valence from their mood. The implications of these results for retail atmospherics are discussed

The Rotation of M Dwarfs Observed by the Apache Point Galactic Evolution Experiment

We present the results of a spectroscopic analysis of rotational velocities in 714 M dwarf stars observed by the SDSS III Apache Point Galactic Evolution Experiment (APOGEE) survey. We use a template fitting technique to estimate $v\sin{i}$ while simultaneously estimating $\log{g}$, $[\text{M}/\text{H}]$, and $T_{\text{eff}}$. We conservatively estimate that our detection limit is 8 km s$^{-1}$. We compare our results to M dwarf rotation studies in the literature based on both spectroscopic and photometric measurements. Like other authors, we find an increase in the fraction of rapid rotators with decreasing stellar temperature, exemplified by a sharp increase in rotation near the M$4$ transition to fully convective stellar interiors, which is consistent with the hypothesis that fully convective stars are unable to shed angular momentum as efficiently as those with radiative cores. We compare a sample of targets observed both by APOGEE and the MEarth transiting planet survey and find no cases were the measured $v\sin{i}$ and rotation period are physically inconsistent, requiring $\sin{i}>1$. We compare our spectroscopic results to the fraction of rotators inferred from photometric surveys and find that while the results are broadly consistent, the photometric surveys exhibit a smaller fraction of rotators beyond the M$4$ transition by a factor of $\sim 2$. We discuss possible reasons for this discrepancy. Given our detection limit, our results are consistent with a bi-modal distribution in rotation that is seen in photometric surveys.Comment: 31 pages, 11 figures, 4 tables. Accepted for publication by A

Prevalence of Palatogingival Grooves in a Libyan Population and Their Relationship with Periodontal Diseases

Aim: The aim of the present study was to evaluate the prevalence of palatogingival grooves and its correlation to the periodontal health in maxillary incisors. Materials and methods: The 200 individuals, aged between 18 and 60 years, were examined for the presence of the palatogingival grooves in the four maxillary incisor teeth. Plaque index (PLI), gingival index (GI) and periodontal disease index (PDI) were used to evaluate the health of the periodontal tissues on the lingual surfaces of the maxillary incisor teeth. Results: The prevalence of palatogingival grooves in the study sample was 7.5% with no significant gender difference. The lateral incisors had the greatest prevalence of palatogingival grooves (1.68%). There were significant differences in periodontal health between teeth with and without palatogingival grooves. Conclusion: This study shows significant association between palatogingival grooves and periodontal disease.&nbsp

Marketing and Public Policy: Transformative Research in Developing Markets

Developing markets are a challenge for researchers who study them and for governments, business leaders, and citizens who strive to improve the quality of life in them. The limitations of the dominant development paradigm coupled with the need to focus on consumers provide tremendous opportunities to engage in truly transformative research. Toward this outcome, several interactive forces must be understood and addressed during research design, management, and implementation. The purpose of this essay is to provide a synthesis—that is, a framework in the form of a conceptual model—with practical applications to transformative research in developing markets and, ultimately, with the broader objective to stimulate new conceptualizations, research, and best practices to transform consumer well-being