Abstract: The climate of West Antarctica is strongly influenced by remote forcing from the tropical Pacific. For example, recent surface warming over West Antarctica reflects atmospheric circulation changes over the Amundsen Sea, driven by an atmospheric Rossby wave response to tropical sea surface temperature (SST) anomalies. Here, it is demonstrated that tropical Pacific SST anomalies also influence the source and transport of marine-derived aerosols to the West Antarctic Ice Sheet. Using records from four firn cores collected along the Amundsen coast of West Antarctica, the relationship between sea ice–modulated chemical species and large-scale atmospheric variability in the tropical Pacific from 1979 to 2010 is investigated. Significant correlations are found between marine biogenic aerosols and sea salts, and SST and sea level pressure in the tropical Pacific. In particular, La Nina–like conditions generate an atmospheric Rossby wave response that influences atmospheric circulation over Pine Island Bay...

Abstract: We report the production of a broad band (ranging from 400 to 900 nm) white light following the monochromatic infrared light (803.5 and 975 nm) excitation of both nominally un-doped and Nd 3+ -doped Y 2 O 3 nano-powders, even up to 20% of Nd 3+ content. Experimental results indicate that such emission feature is a nano-scale phenomenon, cannot be ascribed to an overlap of sharp emission bands in the un-doped case and, even if assisted by the Nd 34 presence, is a host matrix-related process. The measured white light emission is strongly dependent on either environment pressure (a pressure threshold occurs) or pumping power. The rising patterns of the white light emission were found to increase faster for either increasing Nd 3+ content and pumping power or decreasing particle size. Notably, high correlated color temperature (2756 K), color rendering index (99), and efficiency (864 lx/W) values were measured for the un-doped sample under 803.5 nm exciting wavelength.

Abstract: We present new results of uniform spectral analysis of Swift/XRT observations of the X-ray binary system 4U 1957+11. This includes 26 observations of the source made between MJD 54282-55890 (2007 July 01-2011 November 25). All 26 spectra are predominantly thermal and can be modeled well with emission from an accretion disk around a black hole. We analyze all 26 spectra jointly using traditional χ{sup 2} fitting as well as Markov Chain Monte Carlo simulations. The results from both methods agree, and constrain model parameters like inclination, column density, and black hole spin. These results indicate that the X-ray emitting inner accretion disk is inclined to our line of sight by 77.6{sub −2.2}{sup +1.5} deg. Additionally, the other constraints we obtain on parameters such as the column density and black hole spin are consistent with previous X-ray observations. Distances less than 5 kpc are unlikely and not only ruled out based on our analysis but also from other independent observations. Based on model-derived bolometric luminosities, we require the source distance to be >10 kpc if the black hole's mass is >10 M {sub ☉}. If the hole's mass is <10 M {sub ☉}, then the distance could be in the rangemore » of 5-10 kpc.« less

Abstract: Department of Biological Sciences, Florida Atlantic University, Boca Raton, Florida 33431ABSTRACT In terrestrial vertebrates, the pelvic gir-dle can reliably predict locomotor mode. Because of thediminished gravitational effects on positively buoyantbony fish, the same relationship does not appear toexist. However, within the negatively buoyant elasmo-branch fishes, benthic batoids employ pelvic fin bottom-walking and punting as primary or supplementaryforms of locomotion. Therefore, in this study, weemployed geometric and linear morphometrics to inves-tigate if their pelvic girdles exhibit shape characteris-tics similar to those of sprawling terrestrialvertebrates. We tested for correlates of pelvic girdleshape with 1) Order, 2) Family, 3) Swim Mode, and/or4) Punt Mode. Landmarks and semilandmarks wereplaced along outlines of dorsal views of 61 batoid pelvicgirdles (3/3 orders, 10/13 families, 35/72 genera). Thefirst three relative warps explained 88.45% of the vari-ation among individuals (P<0.01%). Only Order andPunt Mode contained groups that were all significantlydifferent from each other (P<0.01%). Discriminantfunction analyses indicated that the majority of varia-tion within each category was due to differences inextension of lateral and prepelvic processes and puboi-schiac bar angle. Over 60% of the original specimensand 55% of the cross-validated specimens were cor-rectly classified. The neutral angle of the propterygium,which articulates with the pelvic girdle, was signifi-cantly different among punt modes, whereas only pec-toral fin oscillators had differently shaped pelvicgirdles when compared with batoids that perform otherswimming modes (P<0.01). Pelvic girdles of batoidsvary greatly, and therefore, likely function in ways notpreviously described in teleost fishes. This study illus-trates that pelvic girdle shape is a good predictor ofpunt mode, some forms of swimming mode, and a spe-cies’ Order. Such correlation between locomotor styleand pelvic girdle shape provides evidence for the con-vergent evolution of morphological features that sup-port both sprawled-gait terrestrial walking and aquaticbottom-walking. J. Morphol. 000:000–000, 2013.

Abstract: This article explores how an experienced teacher navigates the demands of curriculum to implement her inquiry-centered teaching and learning philosophy, and how administrators along the way supported her during this change. Interviews with this classroom teacher surface suggestions for twenty-first-century professional development and support, including the development of equitable, intellectual, and trusting relationships between teachers and administrators, attitudes of curiosity and availability on the part of administrators, and the use of documentation to provide evidence and visibility of meaningful teaching and learning. This article invites teachers interested in change and administrators committed to supporting competent teachers to consider the strategies proposed.

Abstract: Arp2/3 complex-facilitated actin polymerization plays an essential role in a variety of cellular functions including motility, adherence, endocytosis, and trafficking. In the present study, we employ the sea urchin coelomocyte experimental model system to test the hypotheses that Arp2/3 complex-nucleated actin assembly mediates the motility of two unusual cellular protrusions; the cytoplasmic ridges present during coelomocyte spreading, and inducible, tubular-shaped, and neurite-like projections. Our investigations couple pharmacological manipulation employing inhibitors of actin polymerization and the Arp2/3 complex with a wide array of imaging methods including digitally enhanced phase contrast, DIC, and polarization light microscopy of live cells; conventional, confocal and super-resolution light microscopy of fluorescently labeled cells; and scanning and transmission electron microscopy. Taken together, the results of this study indicate that Arp2/3 complex-facilitated actin polymerization underlies the motility of coelomocyte cytoplasmic ridges and tubular projections, that these processes are related to each other, and that they have been preliminarily identified in other cell types. The results also highlight the broad spectrum of actin-based protrusive activities dependent on the Arp2/3 complex and provide additional insights into the pervasive nature of this ubiquitous actin nucleator. Furthermore, we provide the first evidence of a possible mechanistic difference between the impacts of the small molecule drugs BDM and CK666 on the Arp2/3 complex.

Abstract: Ganymede and Callisto are planet-sized moons of Jupiter, with surfaces composed of a mixture of dark dust and bright ice. Similar in size, they both have interiors of half ice and half rock/metal, but Ganymede's interior appears to be segregated by density, while Callisto's interior is mostly mixed. Both moons appear to have subsurface liquid water oceans sandwiched between low-pressure surface ice and high-pressure ice phases deep in their interiors. Ganymede has an intrinsic magnetic field, probably generated by dynamo action in a molten iron core. The surface of Callisto and part of the surface of Ganymede appear to be ancient, dominated by impact cratering and the slow decay of ice sublimating into the surrounding vacuum, leaving behind dark dust. Two-thirds of Ganymede's surface was rejuvenated during a dramatic event at some point in the middle of solar system history, by intense extensional tectonism and possibly cryovolcanism.

Abstract: Liquid water may lurk beneath the frozen surfaces of Jupiter's moon Europa and other icy worlds. Extending ocean science beyond Earth, planetary oceanographers are linking Europa's ocean dynamics to its enigmatic surface geology.

Abstract: Results of theoretical and experimental investigations of local fields in prepercolation ultrathin nanostructured silver films are presented. Numerical calculations based on the film struc- ture obtained by atomic force microscopy imaging indicate that a substantial amplification of the initial exciting field is possible. The effect is experimentally confirmed by luminescence and Raman measurements. © 2014 Society of Photo-Optical Instrumentation Engineers (SPIE) (DOI: 10

Abstract: The Navajo (or Dine’, as they call themselves) were decimated by their Long Walk in the 1860s, but the survivors soon returned to their homeland, bounded by sacred mountains in the high deserts of ...

Abstract: In typical figure–ground displays the figure has shape and is perceived as being in front, whereas the ground is shapeless and recedes to the back. The recent literature on the visual perception of holes has questioned the nature of this coupling between shape and depth both theoretically and empirically. In this paper we provide a theoretical framework that clarifies the underlying issues and we report new evidence supporting the view that the shape of a hole is perceived as the shape of its interior region. Palmer, Davis, Nelson, and Rock (2008 Perception, 37, 1569–1586) showed that the shape of the interior region of a hole is remembered as such, even though the surface visible through it is perceived as farther in depth. The present paper extends this evidence to perceiving holes. Participants performed a speeded shape-matching task in which they compared a surrounded interior region (of either a hole or an object) or its exterior complement with one of several shapes. The results indicate that holes ...

Abstract: The Newar monastic compounds of the Kathmandu Valley (bāhāḥs and bahīs) are the centres of what is arguably the world's oldest continuously practised form of Buddhism. This article presents a preliminary analysis of a survey that revisited these compounds 25 years after the publication of John Locke's exhaustive study in order to understand how these fundamental institutions of Newar Buddhism have been affected by the radical transformations that Nepalese society has undergone since then. It suggests that Newar practitioners of the dharma have often expressed their devotion in ways that are at once traditional and vitally innovative, transforming these compounds as well as the means through which they transform them in myriad ways. The conspicuous democratisation of sponsorship of ‘repairs’ has resulted in alterations that conform to notions of authenticity—old and new, Newar and foreign—as well as deliberate departures from tradition.

Abstract: Computational methods of inferring regions of noncoding DNA that regulate gene activity are important to efficient biological validation of gene regulatory control. In many cases the available resources may allow for relatively few biological assays to be performed, and computational results allow these assays to be tightly focused on the highest confidence candidate regulatory regions. Here, we present a workflow for the computational identification of candidate regulatory regions that incorporates multiple lines of evidence and illustrate its use to select high-confidence targets for experimental verification using the ciliary gene Tektin3 as an example. The Tektin3 protein is vital for ciliogenesis, a process in which cilia are formed. Cilia are important organelles of cells that are involved in numerous activities, and are related to many human diseases. The study of ciliogenesis genes may lead to advances in treatment for related diseases in humans, including diseases caused by malformation of the cilia.

Abstract: We present an analysis of three archival Chandra observations of the black hole V4641 Sgr, performed during a decline into quiescence. The last two observations in the sequence can be modeled with a simple power law. The first spectrum, however, is remarkably similar to spectra observed in Seyfert-2 active galactic nuclei, which arise through a combination of obscuration and reflection from distant material. This spectrum of V4641 Sgr can be fit extremely well with a model including partial-covering absorption and distant reflection. This model recovers a Γ 2.0 power-law incident spectrum, typical of black holes at low Eddington fractions. The implied geometry is plausible in a high-mass X-ray binary like V4641 Sgr, and may be as compelling as explanations invoking Doppler-split line pairs in a jet, and/or unusual Comptonization. We discuss potential implications and means of testing these models.

Abstract: We report the detection of the two-dimensional structure of the radio source associated with the Galactic Center black hole, Sagittarius A*, obtained from Very Long Baseline Array observations at a wavelength of 7 mm. The intrinsic source is modeled as an elliptical Gaussian with major-axis size 35.4 × 12.6 RS in position angle 95° east of north. This morphology can be interpreted in the context of both jet and accretion disk models for the radio emission. There is supporting evidence in large angular-scale multi-wavelength observations for both source models for a preferred axis near 95°. We also place a maximum peak-to-peak change of 15% in the intrinsic major-axis size over five different epochs. Three observations were triggered by detection of near infrared (NIR) flares and one was simultaneous with a large X-ray flare detected by NuSTAR. The absence of simultaneous and quasi-simultaneous flares indicates that not all high energy events produce variability at radio wavelengths. This supports the conclusion that NIR and X-ray flares are primarily due to electron excitation and not to an enhanced accretion rate onto the black hole.

Abstract: The sources and transport pathways of aerosol species in Antarctica remain uncertain, partly due to limited seasonally resolved data from the harsh environment Here, we examine the seasonal cycles of major ions in three high-accumulation West Antarctic ice cores for new information regarding the origin of aerosol species A new method for continuous acidity measurement in ice cores is exploited to provide a comprehensive, charge-balance approach to assessing the major non-sea-salt (nss) species The average nss-anion composition is 41% sulfate (SO42−), 36% nitrate (NO3−), 15% excess-chloride (ExCl−), and 8% methanesulfonic acid (MSA) Approximately 2% of the acid-anion content is neutralized by ammonium (NH4+), and the remainder is balanced by the acidity (Acy ≈ H+ − HCO3−) The annual cycle of NO3− shows a primary peak in summer and a secondary peak in late winter/spring that are consistent with previous air and snow studies in Antarctica The origin of these peaks remains uncertain, however, and is an area of active research A high correlation between NH4+ and black carbon (BC) suggests that a major source of NH4+ is midlatitude biomass burning rather than marine biomass decay, as previously assumed The annual peak in excess chloride (ExCl−) coincides with the late-winter maximum in sea ice extent Wintertime ExCl− is correlated with offshore sea ice concentrations and inversely correlated with temperature from nearby Byrd station These observations suggest that the winter peak in ExCl− is an expression of fractionated sea-salt aerosol and that sea ice is therefore a major source of sea-salt aerosol in the region

Abstract: Understanding how black holes accrete and supply feedback to their environment is one of the outstanding challenges of modern astrophysics. Swift J1910.2-0546 is a candidate black hole low-mass X-ray binary that was discovered in 2012 when it entered an accretion outburst. To investigate the binary configuration and the accretion morphology, we monitored the evolution of the outburst for 3 months at X-ray, UV, optical (B, V, R, I), and near-infrared (J, H, K) wavelengths using Swift and SMARTS. The source evolved from a hard to a soft X-ray spectral state with a relatively cold accretion disk that peaked at 0.5 keV. A Chandra/HETG spectrum obtained during this soft state did not reveal signatures of an ionized disk wind. Both the low disk temperature and the absence of a detectable wind could indicate that the system is viewed at relatively low inclination. The multi-wavelength light curves revealed two notable features that appear to be related to X-ray state changes. First, a prominent flux decrease was observed in all wavebands 1-2 weeks before the source entered the soft state. This dip occurred in (0.6-10 keV) X-rays 6 days later than at longer wavelengths, which could possibly reflect the viscous timescale of the disk. Second, about two weeks after the source transitioned back into the hard state, the UV emission significantly increased while the X-rays steadily decayed. We discuss how these observations may reflect changes in the accretion morphology, perhaps related to the quenching/launch of a jet or the collapse/recovery of a hot flow.

Abstract: Nithard's Histories of the civil wars fought between Louis the Pious's sons reveal much about mid-ninth-century nobility, political values, and the author's changing social position. This article considers how Nithard's immediate familial history affected the text's composition. We argue that his incorporation of authorial voice and detail, crafting of the royal lineage, and emphasis on fraternitas suggest that Nithard employed the text to fight for legitimacy and honour, both familial and individual. We propose that the Histories should be read as a social commemoration of Nithard's familial memories, thus complicating the assumption that family histories were the purview of women.

Abstract: Grooved terrain on Ganymede consists of distinct areas of parallel to subparallel ridges and troughs at a variety of spatial scales. Grooved terrain has been interpreted as the product of tectonism in the form of fault-accommodated distributed lithospheric extension. We use physical analog methods to test the formation of grooved terrain by imbricate normal faulting in response to distributed extension. Faults and fault systems produced in the models are geometrically and kinematically similar to patterns inferred for some grooved terrains on Ganymede. The high degree of similarity between model structures and those observed on Ganymede indicates that rotational half-graben brittle block faulting can explain at least some tectonic resurfacing on Ganymede and that 20% extension is sufficient to form structures analogous to grooved terrain.