Direct imaging constraints on planet populations detected by microlensing

Results from gravitational microlensing suggested the existence of a large population of free-floating planetary mass objects. The main conclusion from this work was partly based on constraints from a direct imaging survey. This survey determined upper limits for the frequency of stars that harbor giant exoplanets at large orbital separations. Aims. We want to verify to what extent upper limits from direct imaging do indeed constrain the microlensing results. We examine the current derivation of the upper limits used in the microlensing study and re-analyze the data from the corresponding imaging survey. We focus on the mass and semi-major axis ranges that are most relevant in context of the microlensing results. We also consider new results from a recent M-dwarf imaging survey as these objects are typically the host stars for planets detected by microlensing. We find that the upper limits currently applied in context of the microlensing results are probably underestimated. This means that a larger fraction of stars than assumed may harbor gas giant planets at larger orbital separations. Also, the way the upper limit is currently used to estimate the fraction of free-floating objects is not strictly correct. If the planetary surface density of giant planets around M-dwarfs is described as df_Planet ~ a^beta da, we find that beta ~ 0.5 - 0.6 is consistent with results from different observational studies probing semi-major axes between ~0.03 - 30 AU. Having a higher upper limit on the fraction of stars that may have gas giant planets at orbital separations probed by the microlensing data implies that more of the planets detected in the microlensing study are potentially bound to stars rather than free-floating. The current observational data are consistent with a rising planetary surface density for giant exoplanets around M-dwarfs out to ~30 AU.Comment: Accepted for publication in A&A as Research Note, 3 page

Service-Relationship Programming Framework for the Social IoT

We argue that for a true realization of innovative programming opportunities for smart spaces, the developers should be equipped with informative tools that assist them in building domain-related applications. Such tools should utilize the services offered by the space's smart things and consider the different relationships that may tie these services opportunistically to build applications. In this paper, we utilize our Inter-thing relationships programming framework to present a distributed programming ecosystem. The framework broadens the restricted set of thing-level relationships of the evolving social IoT paradigm with a set of service-level relationships. Such relationships provide guidance into how services belonging to different things can be combined to build meaningful applications. We also present a uniform way of describing the thing services and the service-level relationships along with new capabilities for the things to dynamically generate their own services, formulate the corresponding programmable interfaces (APIs) and create an ad-hoc network of socially related smart things at runtime. We then present the semantic rules that guide the establishment of IoT applications and finally demonstrate the features of the framework through a proof-of-concept application

Large Magellanic Cloud Microlensing Optical Depth with Imperfect Event Selection

I present a new analysis of the MACHO Project 5.7 year Large Magellanic Cloud (LMC) microlensing data set that incorporates the effects of contamination of the microlensing event sample by variable stars. Photometric monitoring of MACHO LMC microlensing event candidates by the EROS and OGLE groups has revealed that one of these events is likely to be a variable star, while additional data has confirmed that many of the other events are very likely to be microlensing. This additional data on the nature of the MACHO microlensing candidates is incorporated into a simple likelihood analysis to derive a probability distribution for the number of MACHO microlens candidates that are true microlensing events. This analysis shows that 10-12 of the 13 events that passed the MACHO selection criteria are likely to be microlensing events, with the other 1-3 being variable stars. This likelihood analysis is also used to show that the main conclusions of the MACHO LMC analysis are unchanged by the variable star contamination. The microlensing optical depth toward the LMC is = 1.0 +/- 0.3 * 10^{-7}. If this is due to microlensing by known stellar populations, plus an additional population of lens objects in the Galactic halo, then the new halo population would account for 16% of the mass of a standard Galactic halo. The MACHO detection exceeds the expected background of 2 events expected from ordinary stars in standard models of the Milky Way and LMC at the 99.98% confidence level. The background prediction is increased to 3 events if maximal disk models are assumed for both the MilkyWay and LMC, but this model fails to account for the full signal seen by MACHO at the 99.8% confidence level.Comment: 20 pages, 2 postscript figues, accepted by Ap

Differences in Prenatal Tobacco Exposure Patterns among 13 Race/Ethnic Groups in California.

Prenatal tobacco exposure is a significant, preventable cause of childhood morbidity, yet little is known about exposure risks for many race/ethnic subpopulations. We studied active smoking and environmental tobacco smoke (ETS) exposure in a population-based cohort of 13 racially/ethnically diverse pregnant women: white, African American, Hispanic, Native American, including nine Asian/Pacific Islander subgroups: Chinese, Japanese, Korean, Filipino, Cambodian, Vietnamese, Laotian, Samoan, and Asian Indians (N = 3329). Using the major nicotine metabolite, cotinine, as an objective biomarker, we analyzed mid-pregnancy serum from prenatal screening banked in 1999⁻2002 from Southern California in an effort to understand differences in tobacco exposure patterns by race/ethnicity, as well as provide a baseline for future work to assess secular changes and longer-term health outcomes. Prevalence of active smoking (based on age- and race-specific cotinine cutpoints) was highest among African American, Samoan, Native Americans and whites (6.8⁻14.1%); and lowest among Filipinos, Chinese, Vietnamese and Asian Indians (0.3⁻1.0%). ETS exposure among non-smokers was highest among African Americans and Samoans, followed by Cambodians, Native Americans, Vietnamese and Koreans, and lowest among Filipinos, Japanese, whites, and Chinese. At least 75% of women had detectable cotinine. While for most groups, levels of active smoking corresponded with levels of ETS, divergent patterns were also found. For example, smoking prevalence among white women was among the highest, but the group's ETS exposure was low among non-smokers; while Vietnamese women were unlikely to be active smokers, they experienced relatively high ETS exposure. Knowledge of race/ethnic differences may be useful in assessing disparities in health outcomes and creating successful tobacco interventions

High precision microlensing maps of the Galactic bulge

We present detailed maps of the microlensing optical depth and event density over an area of 195 sq. deg towards the Galactic bulge. The maps are computed from synthetic stellar catalogues generated from the Besancon Galaxy Model, which comprises four stellar populations and a three-dimensional extinction map calibrated against the Two-Micron All-Sky Survey. The optical depth maps have a resolution of 15 arcminutes, corresponding to the angular resolution of the extinction map. We compute optical depth and event density maps for all resolved sources above I=19, for unresolved (difference image) sources magnified above this limit, and for bright standard candle sources in the bulge. We show that the resulting optical depth contours are dominated by extinction effects, exhibiting fine structure in stark contrast to previous theoretical optical depth maps. Optical depth comparisons between Galactic models and optical microlensing survey measurements cannot safely ignore extinction or assume it to be smooth. We show how the event distribution for hypothetical J and K-band microlensing surveys, using existing ground-based facilities such as VISTA, UKIRT or CFHT, would be much less affected by extinction, especially in the K band. The near infrared provides a substantial sensitivity increase over current I-band surveys and a more faithful tracer of the underlying stellar distribution, something which upcoming variability surveys such as VVV will be able to exploit. Synthetic population models offer a promising way forward to fully exploit large microlensing datasets for Galactic structure studies.Comment: 8 pages, submitted to MNRA

Effect of HAART on growth parameters and absolute CD4 count among HIV-infected children in a rural community of central Nigeria

Background:Monitoring response to highly active antiretroviral therapy (HAART) in HIV infected children using both laboratory and physical growth parameter is important. But monitoring laboratory parameters could sometimes be challenging in resource-poor settings as the machines used for these measurements may not always be functional or the required technical expertise be available especially in rural areas. Hence, changes in weight-for-age (WAZ), height-for -age (HAZ) and body mass indexfor age (BAZ) Z scores during clinic follow-up visits with or without changes in absolute CD4 count, could be used instead of viral load measurements as indicators of response to HAART in children.Objectives: To determine the effect in children of treatment with HAART - on changes in physical growth using WAZ, HAZ and BAZ and on changes in CD4 count using absolute CD4 count.Methods: Data on demographic/ clinical variables, viral load, absolute CD4 count, and weight and height measurements done at enrolment and at follow-up visits for 72 eligible children < 15 years who were consecutively enrolled into HAART were analysedResults: After nine months of HAART, the median absolute CD4 count increased by 28.2% and median WAZ increased by 28.6%. The reduction in the proportion of children with moderate malnutrition (WAZ < -2) from time of HAART commencement to nine months after HAART, was by 61.5% in those without severe immune suppression (SIS) and by 50% in those with SISConclusion: This study showed that WAZ and absolute CD4 count changes could be useful for monitoring response to HAART in resource –limited settings.Key words: Growth, Absolute CD4 count, Z score, HAAR

Experimental investigation of local half-cone scouring against dam

River morphodynamics and sediment transportSediment-structure interactio

Interoperable communication framework for bridging RESTful and topic-based communication in IoT

The promise of the Internet of Things (IoT) and the many visions of unprecedented and transforming IoT applications are challenged by the realities of a highly fragmented ecosystem of devices, standards and industries. Systems research in IoT is shifting priorities to explore explicit “thing architectures” that promote and enable the friction-free interactions of things despite such fragmentations. In this paper, we focus on overcoming light-weight communication protocol fragmentation. We introduce the Atlas IoT communication framework which enables interactions among things that speak similar or different communication protocols. The framework tools up Atlas things with protocol translator “attachments” that could be either hosted on board the Atlas thing platform, or in the cloud. The translator enables the seamless communication between heterogeneous things through a set of well-defined interfaces. The proposed framework supports seamless communication among the widely adopted Constrained Application Protocol (CoAP), Representational State Transfer (REST) over Hypertext Transfer protocol HTTP, and the Message Queue Telemetry Transport protocol (MQTT). Our framework is carefully designed to facilitate interoperability among heterogeneously communicating things without taxing the performance of things that are homogenously communicating. The framework itself utilizes the topic concept and uses a meta-topic hierarchy to map out and guide the translations. We present the details of the Atlas IoT communication framework and give a detailed benchmarking study to measure the energy consumption and code footprint characteristics of the different aspects of the framework on real hardware platforms. In addition to basic characterizations, we compare our framework to the Eclipse Ponte framework and show how our framework is advantageous in energy consumption and how it is unique in that it does not tangibly penalize the homogeneous communication case

The Effects of Curcumin on ERα, p53, and p21 in the MCF-7 Breast Cancer Cell Line

Curcumin is a golden-yellow flavonoid compound derived from the turmeric plant root that has been used in Chinese and Indian medicine for centuries. Curcumin has been shown to have antioxidant and anti-inflammatory properties, and because of this, has been gaining traction in the field of cancer research. Breast cancer is the most commonly diagnosed cancer in women, and is the second leading cause of cancer death in women, next to lung cancer. Because of the prevalence and mortality of breast cancer, possible therapeutics must be investigated. Due to the beneficial properties of curcumin and pervasiveness of breast cancer, we have decided to investigate their relationship. Our study examines the effects of curcumin, alone and in combination with hormones and anti-hormones, on ERα, p53, and p21 expression in the MCF-7 breast cancer cell line. We utilized western blot analyses, cellular viability assays, and confocal microscopy to gather our data. In order to deplete any endogenous steroids or effectors, breast cancer cells were cultured in a medium containing 5% charcoal-stripped fetal bovine serum for six days before treatment. Western blot analysis revealed significant downregulation of ERα in a concentration-dependent manner when cells were treated with increasing concentrations of curcumin (5μM-100μM). In the hormone studies, when curcumin (40μM) is combined with estradiol, it significantly downregulates ERα, even more so than when either compound is used on its own. This demonstrates the additive effects of curcumin, and that it is able to compete with the estrogen and anti-estrogens for receptor binding. The effects of curcumin on p53 are also promising. In the concentration studies, western blotting revealed a significant concentration-dependent increase in p53 levels with increasing concentrations of curcumin (5μM-100μM). Lastly, the effects of curcumin on p21 show a significant concentration-dependent increase in p21 levels with increasing concentrations of curcumin (5μM-100μM). Cellular viability studies show a significant decrease in cellular proliferation after treatment with curcumin, similar to the levels seen with antiestrogens ICI and tamoxifen. Overall, the effects of curcumin on the MCF-7 breast cancer cell line show significant downregulation of ERα, significant upregulation of p53 and p21, and a significant decrease in breast cancer proliferation. This constellation of findings is promising, and our studies provide a groundwork for further investigation of this compound as it relates to breast cancer progression clinically