383 research outputs found

    Orthognathic Surgery past, present, and future

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    Orthognathic surgery has been performed for over two centuries with the first procedure occurring in the 1860s. It was not until the late 1950s with the pioneering work of Obwegeser that the modern orthognathic surgery era began. From the beginning, oral surgeons and orthodontists have worked in parallel fashion; advances in both disciplines have led to what is now routinely performed. New and exciting developments are underway not only in diagnosis but also in treatment planning with computer aided surgical simulation and the use of artificial intelligence (AI) to enhance patient treatment outcomes. The purpose of this article is to briefly review the history of orthognathic surgery, to examine the present status and to highlight emerging technologies and advancements

    Ancient Maya Rural Settlement Patterns, Household Cooperation, and Regional Subsistence Interdependency in the RĂ­o Bec Area: Contributions from G-LiHT

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    Research on intensive agricultural features contributes to the social relations of farming, including the means by which farmers mobilize labor and the possible destination of surplus. Lidar provides high-resolution data on ancient houses and agricultural features at a regional scale. This paper uses lidar data from NASA’s G-LiHT airborne imager to derive insights about rural demography, interhousehold cooperation, and subsistence interdependency among the ancient Maya. We assess the differences in intensity of agricultural investment in rural and urban areas of the Río Bec region of southern Campeche and Quintana Roo, Mexico, leading to inferences about regional food exchange and complex economies. The scale of interconnected ridges and terraces clearly implies interhousehold cooperation, yet this cooperation was not centralized. Rather, we envision a landscape of smallholders who jointly planned the layout and articulation of agricultural features but pooled most of their labor at the level of the household

    HerMES: the rest-frame UV emission and a lensing model for the z= 6.34 luminous dusty starburst galaxy HFLS3

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    We discuss the rest-frame ultraviolet emission from the starbursting galaxy HFLS3 at a redshift of 6.34. The galaxy was discovered in Herschel/SPIRE data due to its red color in the submillimeter wavelengths from 250 to 500 ÎŒm. Keck/NIRC2 K s -band adaptive optics imaging data showed two potential near-IR counterparts near HFLS3. Previously, the northern galaxy was taken to be in the foreground at z = 2.1, while the southern galaxy was assumed to be HFLS3's near-IR counterpart. The recently acquired Hubble/WFC3 and Advanced Camera for Surveys (ACS) imaging data show conclusively that both optically bright galaxies are in the foreground at z < 6. A new lensing model based on the Hubble imaging data and the millimeter-wave continuum emission yields a magnification factor of 2.2 ± 0.3, with a 95% confidence upper limit on the magnification of 3.5. When corrected for lensing, the instantaneous star formation rate is 1320 M ☉ yr–1, with the 95% confidence lower limit around 830 M ☉ yr–1. The dust and stellar masses of HFLS3 from the same spectral energy distribution (SED) models are at the level of 3 × 108 M ☉ and ~5 × 1010 M ☉, respectively, with large systematic uncertainties on assumptions related to the SED model. With Hubble/WFC3 images, we also find diffuse near-IR emission about 0.5 arcsec (~3 kpc) to the southwest of HFLS3 that remains undetected in the ACS imaging data. The emission has a photometric redshift consistent with either z ~ 6 or a dusty galaxy template at z ~ 2

    Environment of the submillimeter-bright massive starburst HFLS3 at z∌z\sim6.34

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    We describe the search for Lyman-break galaxies (LBGs) near the sub-millimeter bright starburst galaxy HFLS3 at zz==6.34 and a study on the environment of this massive galaxy during the end of reionization.We performed two independent selections of LBGs on images obtained with the \textit{Gran Telescopio Canarias} (GTC) and the \textit{Hubble Space Telescope} (HST) by combining non-detections in bands blueward of the Lyman-break and color selection. A total of 10 objects fulfilling the LBG selection criteria at zz>>5.5 were selected over the 4.54 and 55.5 arcmin2^2 covered by our HST and GTC images, respectively. The photometric redshift, UV luminosity, and the star-formation rate of these sources were estimated with models of their spectral energy distribution. These zz∌\sim6 candidates have physical properties and number densities in agreement with previous results. The UV luminosity function at zz∌\sim6 and a Voronoi tessellation analysis of this field shows no strong evidence for an overdensity of relatively bright objects (mF105W_{F105W}<<25.9) associated with \textit{HFLS3}. However, the over-density parameter deduced from this field and the surface density of objects can not excluded definitively the LBG over-density hypothesis. Moreover we identified three faint objects at less than three arcseconds from \textit{HFLS3} with color consistent with those expected for zz∌\sim6 galaxies. Deeper data are needed to confirm their redshifts and to study their association with \textit{HFLS3} and the galaxy merger that may be responsible for the massive starburst.Comment: 14 pages, 12 figures, accepted for publication in Ap

    Evaluation Research and Institutional Pressures: Challenges in Public-Nonprofit Contracting

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    This article examines the connection between program evaluation research and decision-making by public managers. Drawing on neo-institutional theory, a framework is presented for diagnosing the pressures and conditions that lead alternatively toward or away the rational use of evaluation research. Three cases of public-nonprofit contracting for the delivery of major programs are presented to clarify the way coercive, mimetic, and normative pressures interfere with a sound connection being made between research and implementation. The article concludes by considering how public managers can respond to the isomorphic pressures in their environment that make it hard to act on data relating to program performance.This publication is Hauser Center Working Paper No. 23. The Hauser Center Working Paper Series was launched during the summer of 2000. The Series enables the Hauser Center to share with a broad audience important works-in-progress written by Hauser Center scholars and researchers

    HerMES: Current Cosmic Infrared Background Estimates Can be Explained by Known Galaxies and their Faint Companions at z < 4

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    We report contributions to cosmic infrared background (CIB) intensities originating from known galaxies and their faint companions at submillimeter wavelengths. Using the publicly-available UltraVISTA catalog, and maps at 250, 350, and 500 {\mu}m from the \emph{Herschel} Multi-tiered Extragalactic Survey (HerMES), we perform a novel measurement that exploits the fact that uncatalogued sources may bias stacked flux densities --- particularly if the resolution of the image is poor --- and intentionally smooth the images before stacking and summing intensities. By smoothing the maps we are capturing the contribution of faint (undetected in K_S ~ 23.4) sources that are physically associated, or correlated, with the detected sources. We find that the cumulative CIB increases with increased smoothing, reaching 9.82 +- 0.78, 5.77 +- 0.43, and 2.32 +- 0.19 nWm−2sr−1\, \rm nW m^{-2} sr^{-1} at 250, 350, and 500 {\mu}m at 300 arcsec FWHM. This corresponds to a fraction of the fiducial CIB of 0.94 +- 0.23, 1.07 +- 0.31, and 0.97 +- 0.26 at 250, 350, and 500 {\mu}m, where the uncertainties are dominated by those of the absolute CIB. We then propose, with a simple model combining parametric descriptions for stacked flux densities and stellar mass functions, that emission from galaxies with log(M/Msun) > 8.5 can account for the most of the measured total intensities, and argue against contributions from extended, diffuse emission. Finally, we discuss prospects for future survey instruments to improve the estimates of the absolute CIB levels, and observe any potentially remaining emission at z > 4.Comment: Accepted to ApJL. 6 Pages, 3 figure

    The evolution of the dust temperatures of galaxies in the SFR–M∗plane up to z ~ 2

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    We study the evolution of the dust temperature of galaxies in the SFR−M ∗ plane up to z ∌ 2 using far-infrared and submillimetre observations from the Herschel Space Observatory taken as part of the PACS Evolutionary Probe (PEP) and Herschel Multi-tiered Extragalactic Survey (HerMES) guaranteed time key programmes. Starting from a sample of galaxies with reliable star-formation rates (SFRs), stellar masses (M ∗ ) and redshift estimates, we grid the SFR−M ∗ parameter space in several redshift ranges and estimate the mean dust temperature (T dust ) of each SFR–M ∗ −z bin. Dust temperatures are inferred using the stacked far-infrared flux densities (100–500ÎŒm) of our SFR–M ∗ −z bins. At all redshifts, the dust temperature of galaxies smoothly increases with rest-frame infrared luminosities (L IR ), specific SFRs (SSFR; i.e., SFR/M ∗ ), and distances with respect to the main sequence (MS) of the SFR−M ∗ plane (i.e., Δlog(SSFR) MS = log[SSFR(galaxy)/SSFR MS (M ∗ ,z)]). The T dust −SSFR and T dust – Δlog(SSFR) MS correlations are statistically much more significant than the T dust −L IR one. While the slopes of these three correlations are redshift-independent, their normalisations evolve smoothly from z = 0 and z ∌ 2. We convert these results into a recipe to derive T dust from SFR, M ∗ and z, valid out to z ∌ 2 and for the stellar mass and SFR range covered by our stacking analysis. The existence of a strong T dust −Δlog(SSFR) MS correlation provides us with several pieces of information on the dust and gas content of galaxies. Firstly, the slope of the T dust −Δlog(SSFR) MS correlation can be explained by the increase in the star-formation efficiency (SFE; SFR/M gas ) with Δlog(SSFR) MS as found locally by molecular gas studies. Secondly, at fixed Δlog(SSFR) MS , the constant dust temperature observed in galaxies probing wide ranges in SFR and M ∗ can be explained by an increase or decrease in the number of star-forming regions with comparable SFE enclosed in them. And thirdly, at high redshift, the normalisation towards hotter dust temperature of the T dust −Δlog(SSFR) MS correlation can be explained by the decrease in the metallicities of galaxies or by the increase in the SFE of MS galaxies. All these results support the hypothesis that the conditions prevailing in the star-forming regions of MS and far-above-MS galaxies are different. MS galaxies have star-forming regions with low SFEs and thus cold dust, while galaxies situated far above the MS seem to be in a starbursting phase characterised by star-forming regions with high SFEs and thus hot dust

    The source counts of submillimetre galaxies detected at 1.1 mm

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    The source counts of galaxies discovered at sub-millimetre and millimetre wavelengths provide important information on the evolution of infrared-bright galaxies. We combine the data from six blank-field surveys carried out at 1.1 mm with AzTEC, totalling 1.6 square degrees in area with root-mean-square depths ranging from 0.4 to 1.7 mJy, and derive the strongest constraints to date on the 1.1 mm source counts at flux densities S(1100) = 1-12 mJy. Using additional data from the AzTEC Cluster Environment Survey to extend the counts to S(1100) ~ 20 mJy, we see tentative evidence for an enhancement relative to the exponential drop in the counts at S(1100) ~ 13 mJy and a smooth connection to the bright source counts at >20 mJy measured by the South Pole Telescope; this excess may be due to strong lensing effects. We compare these counts to predictions from several semi-analytical and phenomenological models and find that for most the agreement is quite good at flux densities > 4 mJy; however, we find significant discrepancies (>3sigma) between the models and the observed 1.1 mm counts at lower flux densities, and none of them are consistent with the observed turnover in the Euclidean-normalised counts at S(1100) < 2 mJy. Our new results therefore may require modifications to existing evolutionary models for low luminosity galaxies. Alternatively, the discrepancy between the measured counts at the faint end and predictions from phenomenological models could arise from limited knowledge of the spectral energy distributions of faint galaxies in the local Universe.Comment: 16 pages, 3 figures, 4 tables; accepted for publication in MNRA

    Prospectus, February 4, 1982

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    WE WANT YOU FOR STUGO; News In Brief; More StuGo prospects; Letters To The Editor: She thinks StuGo should attend to other problems. Thanks to former president; Exercise your right to vote; Nautical look \u27in\u27 this spring; PC Happenings
: Improve thyself, AHT offers Sweetheart raffle, Go Western in Ski Club, Managing your money; Teleview to make debut in March; Need financial aid? Here\u27s how to get it; Teleview to make debut in March; Sheriff discusses overcrowding at jail; Increased enrollment results in overcrowding; Com Club sets election; \u27Snow\u27 chance of a heat wave: Surprise storm hits area for 3rd weekend in a row!; Sunday\u27s snow nearly sets record; Not end of candy business: Chris\u27 reopening; Low-cost trips, tours offered to college students; Keeping friends is series topic; Few in Illinois have tax problems; J. Geils is back; Storm postpones athletic events; College bowling tourney held at Arrowhead; Kinks\u27 latest gives what we want; Big Daddy: rockabilly party; Rick James leads new Punk Funk wave; Something crazy was expected, but...: Ozzy pays back Champaign; This week\u27s happenings: Clubs offer local talent; Abba\u27s new album adds to their success; Reviewer enjoys brass band; \u27Dragonriders\u27 series deals in Pem fantasy; Classifieds; \u27Roots\u27 begins Feb. 9; Euchre tourney begins tonight; Skating party is Feb. 8; Top boxing prospect appearing at Danville; PC track team places in two events; Cagers keep winning streak alive with Joliet victory; Makeever leads Cobras to victory; Lady Cobras suffer defeat; Today\u27s farmer from new era; Burnham establishes scholarship; Farm technology is tapering off; Wind and cold make bitter combinationhttps://spark.parkland.edu/prospectus_1982/1030/thumbnail.jp
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