Growth and the expression of alternative life cycles in the salamander \u3ci\u3eAmbystoma talpoideum\u3c/i\u3e (Caudata: Ambystomatidae)

Complex life cycles (CLCs) contain larval and adult phases that are morphologically and ecologically distinct. Simple life cycles (SLCs) have evolved from CLCs repeatedly in a wide variety of lineages but the processes that may underlie the transition have rarely been identified or investigated experimentally. We examined the influence of larval growth rate on the facultative expression of alternative life cycles (metamorphosis or maturation as gill-bearing adults [= paedomorphosis]) in the salamander Ambystoma talpoideum. We manipulated growth rates by altering the amount of food individuals received throughout larval development. The expression of alternative life cycles in A. talpoideum is influenced by growth via food levels, but the same growth rates at different points in the larval period elicit different responses. Individuals were more likely to metamorphose (i.e. express a CLC) when food levels and growth rates were high later in development and more likely to mature without metamorphosing (SLC) when growth rates were comparatively low during the same point in development. Growth rates at particular points in development, rather than overall larval growth rate, may be an important proximate factor in salamander life-cycle evolution

Introduction: Ain’t It Evil to Live Backwards? : A Hip Hop Perspective of Religion

Historically, Black religion has been the cornerstone of the African experience in America. Due to the peculiar institution” of slavery and the ways this institutional residue still affect the lives of slave descendants, Hip Hop provides a forum to simultaneously acknowledge similarities and highlight differences. What scholars of religion and Hip Hop studies have revealed are the ways in which the effectiveness and our very understanding of “religion” changes when we bring Hip Hop in to the mix

Astronomical, physical, and meteorological parameters for planetary atmospheres

A newly compiled table of astronomical, physical, and meteorological parameters for planetary atmospheres is presented. Formulae and explanatory notes for their application and a complete listing of sources are also given

Extremely Irradiated Hot Jupiters: Non-Oxide Inversions, H- Opacity, and Thermal Dissociation of Molecules

Extremely irradiated hot Jupiters, exoplanets reaching dayside temperatures ${>}$2000 K, stretch our understanding of planetary atmospheres and the models we use to interpret observations. While these objects are planets in every other sense, their atmospheres reach temperatures at low pressures comparable only to stellar atmospheres. In order to understand our \textit{a priori} theoretical expectations for the nature of these objects, we self-consistently model a number of extreme hot Jupiter scenarios with the PHOENIX model atmosphere code. PHOENIX is well-tested on objects from cool brown dwarfs to expanding supernovae shells and its expansive opacity database from the UV to far-IR make PHOENIX well-suited for understanding extremely irradiated hot Jupiters. We find several fundamental differences between hot Jupiters at temperatures ${>}$2500 K and their cooler counterparts. First, absorption by atomic metals like Fe and Mg, molecules including SiO and metal hydrides, and continuous opacity sources like H$^-$ all combined with the short-wavelength output of early-type host stars result in strong thermal inversions, without the need for TiO or VO. Second, many molecular species, including H$_2$O, TiO, and VO are thermally dissociated at pressures probed by eclipse observations, biasing retrieval algorithms that assume uniform vertical abundances. We discuss other interesting properties of these objects, as well as future prospects and predictions for observing and characterizing this unique class of astrophysical object, including the first self-consistent model of the hottest known jovian planet, KELT-9b.Comment: 23 pages, 16 figures, 1 table. Submitted to Ap

Consent Verification Under Evolving Privacy Policies

Personal data provides important business value, for example, in the personalization of services. In addition, companies are moving toward new business models, in which products and services are offered without charge to users, but in exchange for targeted advertising revenue. New privacy regulations require organizations to explicitly state their data practices in privacy policies, including which data types will be collected. By consenting to data collections described in a policy, the user acknowledges that he or she is granting the company the authorizations needed to access their data. When data practices change, a new version of the policy is released. This release can occur a few times a year, when requirements are rapidly changing for the collection and processing of personal data. Furthermore, the user may change his or her privacy consent by opting in or out of the policy. We propose a formal framework to support companies and users in their understanding of policies evolution under consent regime that supports both retroactive and non-retroactive consent and consent revocation. Preliminary results include an ontology for policy evolution, expressed in Description Logic, that can be used to formalize consent and data collection logs and then query for which data types can be legally accessed

The Influence of Host Star Spectral Type on Ultra-Hot Jupiter Atmospheres

Ultra-hot Jupiters are the most highly irradiated gas giant planets, with equilibrium temperatures from 2000 to over 4000 K. Ultra-hot Jupiters are amenable to characterization due to their high temperatures, inflated radii, and short periods, but their atmospheres are atypical for planets in that the photosphere possesses large concentrations of atoms and ions relative to molecules. Here we evaluate how the atmospheres of these planets respond to irradiation by stars of different spectral type. We find that ultra-hot Jupiters exhibit temperature inversions that are sensitive to the spectral type of the host star. The slope and temperature range across the inversion both increase as the host star effective temperature increases due to enhanced absorption at short wavelengths and low pressures. The steep temperature inversions in ultra-hot Jupiters around hot stars result in increased thermal dissociation and ionization compared to similar planets around cooler stars. The resulting increase in H$^{-}$ opacity leads to a transit spectrum that has muted absorption features. The emission spectrum, however, exhibits a large contrast in brightness temperature, a signature that will be detectable with both secondary eclipse observations and high-dispersion spectroscopy. We also find that the departures from local thermodynamic equilibrium in the stellar atmosphere can affect the degree of heating caused by atomic metals in the planet's upper atmosphere. Additionally, we further quantify the significance of heating by different opacity sources in ultra-hot Jupiter atmospheres.Comment: 13 pages, 9 figures, 2 tables. Accepted for publication in Ap

On the Rare Endemic Hydrophyllum brownei Kral & Bates (Browne\u27s Waterleaf): New Population Information and a Recommendation for Change in Status

Hydrophyllum brownei Krai & Bates (Browne\u27s waterleaf), newly described in 1991, is endemic to the Ouachita Mountain Natural Division of Arkansas. For the purpose of better understanding population parameters within which H. brownei grows, ranges of shade values, population extents, and population distance relationships to streams were measured. Hydrophyllum brownei grows in extremely high shade, in populations of widely varying sizes, and always in association with a stream system. In order to list species associated with H. brownei, vouchers of species assemblages were collected at the H. brownei sites visited. The species is designated as critically imperiled globally because of its extreme rarity (Gl). It is also extremely rare in Arkansas (Si) according to NatureServe and the Arkansas Natural Heritage Commission. Previously unknown populations were discovered in this study, and a recommendation to lower species rarity rank is made. However, based upon information gathered about population parameters, it is recommended that the species be reduced in status only to the global rank of G2 (imperiled globally because of rarity) and the state rank of S2 (very rare). Hydrophyllum brownei is currently known from 26 distinct sites, nine of which were discovered in 2002. Because H. brownei is a rare endemic to the Ouachita Mountains, continued intermittent monitoring of its populations is advised