1,558 research outputs found

    A Caging Inspired Gripper using Flexible Fingers and a Movable Palm

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    This paper proposes the design of a robotic gripper motivated by the bin-picking problem, where a variety of objects need to be picked from cluttered bins. The presented gripper design focuses on an enveloping cage-like approach, which surrounds the object with three hooked fingers, and then presses into the object with a movable palm. The fingers are flexible and imbue grasps with some elasticity, helping to conform to objects and, crucially, adding friction to cases where an object cannot be caged. This approach proved effective on a set of basic shapes, such as cuboids and cylinders, in which every object could be grasped. In particular, flat bottom parts could be grasped in a very stable manner, as demonstrated by testing grasps with multiple 5N and 10N disturbances. A set of supermarket items were also tested, highlighting promising features such as effective grasping of fruits and vegetables, as well as some limitations in the current embodiment, which is not always able to slip the fingers underneath objects

    Climate, cryosphere and carbon cycle controls on Southeast Atlantic orbital-scale carbonate deposition since the Oligocene (30–0 Ma)

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    The evolution of the Cenozoic cryosphere from unipolar to bipolar over the past 30 million years (Myr) is broadly known. Highly resolved records of carbonate (CaCO_{3}) content provide insight into the evolution of regional and global climate, cryosphere, and carbon cycle dynamics. Here, we generate the first Southeast Atlantic CaCO3 content record spanning the last 30 Myr, derived from X-ray fluorescence (XRF) ln(Ca / Fe) data collected at Ocean Drilling Program Site 1264 (Walvis Ridge, SE Atlantic Ocean). We present a comprehensive and continuous depth and age model for the entirety of Site 1264 (∼ 316 m; 30 Myr). This constitutes a key reference framework for future palaeoclimatic and palaeoceanographic studies at this location. We identify three phases with distinctly different orbital controls on Southeast Atlantic CaCO_{3} deposition, corresponding to major developments in climate, the cryosphere and the carbon cycle: (1) strong ∼ 110 kyr eccentricity pacing prevails during Oligocene–Miocene global warmth (∼ 30–13 Ma), (2) increased eccentricity-modulated precession pacing appears after the middle Miocene Climate Transition (mMCT) (∼ 14–8 Ma), and (3) pervasive obliquity pacing appears in the late Miocene (∼ 7.7–3.3 Ma) following greater importance of high-latitude processes, such as increased glacial activity and high-latitude cooling. The lowest CaCO_{3} content (92 %–94 %) occurs between 18.5 and 14.5 Ma, potentially reflecting dissolution caused by widespread early Miocene warmth and preceding Antarctic deglaciation across the Miocene Climatic Optimum (∼ 17–14.5 Ma) by 1.5 Myr. The emergence of precession pacing of CaCO_{3} deposition at Site 1264 after ∼ 14 Ma could signal a reorganisation of surface and/or deep-water circulation in this region following Antarctic reglaciation at the mMCT. The increased sensitivity to precession at Site 1264 between 14 and 13 Ma is associated with an increase in mass accumulation rates (MARs) and reflects increased regional CaCO3 productivity and/or recurrent influxes of cooler, less corrosive deep waters. The highest carbonate content (%CaCO_{3}) and MARs indicate that the late Miocene–early Pliocene Biogenic Bloom (LMBB) occurs between ∼ 7.8 and 3.3 Ma at Site 1264; broadly contemporaneous with the LMBB in the equatorial Pacific Ocean. At Site 1264, the onset of the LMBB roughly coincides with appearance of strong obliquity pacing of %CaCO_{3}, reflecting increased high-latitude forcing. The global expression of the LMBB may reflect increased nutrient input into the global ocean resulting from enhanced aeolian dust and/or glacial/chemical weathering fluxes, due to enhanced glacial activity and increased meridional temperature gradients. Regional variability in the timing and amplitude of the LMBB may be driven by regional differences in cooling, continental aridification and/or changes in ocean circulation in the late Miocene

    Ursinus College Alumni Journal, November 1964

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    President\u27s letter • Charles David Mattern, 1907-1964: With tributes from some of his colleagues • Professor without portfolio: A portrait of the Rev. John Henry Augustus Bomberger, D. D., founder and first president of Ursinus College and School of Theology • The contemporary French literary scene • Quarter-century change . . . decade planning • Student facilities building construction moves steadily toward completion by mid-\u2765 • Joseph Chapline, \u2742, former computer expert builds organs - tells how and why • Larry Koch, \u2762, advances with Western Electric • Schellhase saga • Insurance executive, author - historian, two new members of Ursinus Board • The 1964 European travel seminar • Yale Press to publish Dr. Foster\u27s volumes • Four Ursinus alumni attend campus conference for furloughed missionaries • Pancoast, \u2737 elected to Pennsylvania House of Representatives • Collegeville comes to life as Ursinus students return • Founders Day focus on distinguished alumni • Remarks presenting portrait of President of Ursinus Board • Gutenberg Bible reproductions presented by Henry Pfeiffer, \u2748 • Loyalty Fund report: October 10, 1964 • Sports victories, crowning of Queen Jeanne, feature 1964 Homecoming Day at Ursinus • Twenty-three bear cubs in Ursinus freshman class • Frederick Wentz named college business manager • Another John H. A. Bomberger • Alumni news and notes • Weddings • Births • Necrology • Former Dean dead at 83 • Vice-president of directors dies unexpectedly November 1 • Former board member dies • Ursinus Women\u27s Club luncheon December 5 • Chef Colameco hurt in railroad wreck • You need a will . . . and Ursinus needs to be rememberedhttps://digitalcommons.ursinus.edu/alumnijournal/1081/thumbnail.jp

    Phylogenetic relationships of cone snails endemic to Cabo Verde based on mitochondrial genomes

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    Background: Due to their great species and ecological diversity as well as their capacity to produce hundreds of different toxins, cone snails are of interest to evolutionary biologists, pharmacologists and amateur naturalists alike. Taxonomic identification of cone snails still relies mostly on the shape, color, and banding patterns of the shell. However, these phenotypic traits are prone to homoplasy. Therefore, the consistent use of genetic data for species delimitation and phylogenetic inference in this apparently hyperdiverse group is largely wanting. Here, we reconstruct the phylogeny of the cones endemic to Cabo Verde archipelago, a well-known radiation of the group, using mitochondrial (mt) genomes. Results: The reconstructed phylogeny grouped the analyzed species into two main clades, one including Kalloconus from West Africa sister to Trovaoconus from Cabo Verde and the other with a paraphyletic Lautoconus due to the sister group relationship of Africonus from Cabo Verde and Lautoconus ventricosus from Mediterranean Sea and neighboring Atlantic Ocean to the exclusion of Lautoconus endemic to Senegal (plus Lautoconus guanche from Mauritania, Morocco, and Canary Islands). Within Trovaoconus, up to three main lineages could be distinguished. The clade of Africonus included four main lineages (named I to IV), each further subdivided into two monophyletic groups. The reconstructed phylogeny allowed inferring the evolution of the radula in the studied lineages as well as biogeographic patterns. The number of cone species endemic to Cabo Verde was revised under the light of sequence divergence data and the inferred phylogenetic relationships. Conclusions: The sequence divergence between continental members of the genus Kalloconus and island endemics ascribed to the genus Trovaoconus is low, prompting for synonymization of the latter. The genus Lautoconus is paraphyletic. Lautoconus ventricosus is the closest living sister group of genus Africonus. Diversification of Africonus was in allopatry due to the direct development nature of their larvae and mainly triggered by eustatic sea level changes during the Miocene-Pliocene. Our study confirms the diversity of cone endemic to Cabo Verde but significantly reduces the number of valid species. Applying a sequence divergence threshold, the number of valid species within the sampled Africonus is reduced to half.Spanish Ministry of Science and Innovation [CGL2013-45211-C2-2-P, CGL2016-75255-C2-1-P, BES-2011-051469, BES-2014-069575, Doctorado Nacional-567]info:eu-repo/semantics/publishedVersio

    Ursinus College Alumni Journal, March 1964

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    Standing room only • New student facilities building • Campaign receipts reach $285,765 at mid-March • Matching gifts • Mid-year report of 1964 Loyalty Fund campaign • Income while you live . . . benefaction when you die • Cutting campus • John Fitzgerald Kennedy • Eccentricities of our political life • A bitter dramatic example • Crisis of conscience in Dallas • Student reaction to November 22-25 • Two recipients for 1964 alumni award • The class of 1911 • The alumni album: C. Richard Snyder, \u2729; William D. Reimert, \u2724; Wainright E. H. Diehl, \u2751; Marguerite Goldthwaite Godshall, \u2732; Franklin E. Morris, \u2741; J. William Ditter, Jr., \u2743; Robert Poole, III, \u2750; Bain and Edwards\u27 sons: football foes • Nominees for alumni association offices • Class notes • Weddings • Births • Necrology • Regionalshttps://digitalcommons.ursinus.edu/alumnijournal/1079/thumbnail.jp

    Precision luminosity measurements at LHCb

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    Measuring cross-sections at the LHC requires the luminosity to be determined accurately at each centre-of-mass energy √s. In this paper results are reported from the luminosity calibrations carried out at the LHC interaction point 8 with the LHCb detector for √s = 2.76, 7 and 8 TeV (proton-proton collisions) and for √sNN = 5 TeV (proton-lead collisions). Both the "van der Meer scan" and "beam-gas imaging" luminosity calibration methods were employed. It is observed that the beam density profile cannot always be described by a function that is factorizable in the two transverse coordinates. The introduction of a two-dimensional description of the beams improves significantly the consistency of the results. For proton-proton interactions at √s = 8 TeV a relative precision of the luminosity calibration of 1.47% is obtained using van der Meer scans and 1.43% using beam-gas imaging, resulting in a combined precision of 1.12%. Applying the calibration to the full data set determines the luminosity with a precision of 1.16%. This represents the most precise luminosity measurement achieved so far at a bunched-beam hadron collider

    Ursinus College Alumni Journal, August 1963

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    The President writes • The uses and limitations of words • Commencement 1963 • 3,032 pledge 509,081;2,809contribute509,081; 2,809 contribute 192,568 • Loyalty Fund committee reorganized • Joseph J. Lynch, college steward • A description of the new dining hall • Chemistry changes • NSF grants for bio profs • Teaching awards • Pilot project: Physics chemistry mathematics • The not-so-ugly American • Best track season in Ursinus history • Double your dollars • Things are looking up • Preliminary thoughts on wills • Reading, writing, and Mazurkiewicz • The augmented Roman alphabet • Edwin C. Myers, \u2764 and Frederic W. Yocum, Jr. \u2764 • Eugene J. Bradford, \u2736 • Robert A. Petersen, \u2760 • Sue Harman, \u2765 • Results of the 1963 Loyalty Fund campaign • The leaders • Contributors to the 1963 Loyalty Fund • Ursinus alumni at Methacton High School • Class notes • Weddings • Births • Necrology • Our role as alumnihttps://digitalcommons.ursinus.edu/alumnijournal/1077/thumbnail.jp

    Differential branching fraction and angular analysis of the decay B0→K∗0μ+μ−

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    The angular distribution and differential branching fraction of the decay B 0→ K ∗0 μ + μ − are studied using a data sample, collected by the LHCb experiment in pp collisions at s√=7 TeV, corresponding to an integrated luminosity of 1.0 fb−1. Several angular observables are measured in bins of the dimuon invariant mass squared, q 2. A first measurement of the zero-crossing point of the forward-backward asymmetry of the dimuon system is also presented. The zero-crossing point is measured to be q20=4.9±0.9GeV2/c4 , where the uncertainty is the sum of statistical and systematic uncertainties. The results are consistent with the Standard Model predictions

    Measurements of the branching fractions of B+→ppK+ decays

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    The branching fractions of the decay B+ → pp̄K+ for different intermediate states are measured using data, corresponding to an integrated luminosity of 1.0 fb-1, collected by the LHCb experiment. The total branching fraction, its charmless component Mpp̄ < 2.85 GeV/c2 and the branching fractions via the resonant cc̄ states η c(1S) and ψ(2S) relative to the decay via a J/ψ intermediate state are [Equation not available: see fulltext.] Upper limits on the B + branching fractions into the η c(2S) meson and into the charmonium-like states X(3872) and X(3915) are also obtained

    Searches for B0(s)→J/ψppˉ and B+→J/ψppˉπ+ decays

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    The results of searches for B0(s)→J/ψ pp¯ and B + → J/ψ p p¯ π+ decays are reported. The analysis is based on a data sample, corresponding to an integrated luminosity of 1.0 fb−1 of pp collisions, collected with the LHCb detector. An excess with 2.8 σ significance is seen for the decay B0s→J/ψ pp¯ and an upper limit on the branching fraction is set at the 90 % confidence level: B(B0s→J/ψ pp¯) < 4.8 × 10−6, which is the first such limit. No significant signals are seen for B0 → J/ψ pp¯ and B+ → J/ψ pp¯ π + decays, for which the corresponding limits are set: B(B0→J/ψ pp¯) < 5.2 × 10−7, which significantly improves the existing limit; and B(B+→J/ψ pp¯π+) < 5.0 × 10−7, which is the first limit on this branching fraction
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