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Upper Marlboro, VT, United States

Marlboro College is an intentionally small, coeducational, academically rigorous liberal-arts college located in Marlboro, Vermont, USA with 235 students. Students at Marlboro create an individualized course of study in collaboration with faculty members and participate in a self-governing community. Students pursue a self-designed, often inter-disciplinary, Plan of Concentration based on their academic interests that culminates in a major body of scholarship. Wikipedia.

Ollis M.A.,Marlboro College
European Journal of Combinatorics | Year: 2014

Let m be an odd powerful number. We show that there is a sequenceable group of order 3. m and hence a complete Latin square of that order. Further, the sequencings we construct are starter-translate and so they may be combined with themselves and other sequencings to construct complete Latin squares for many more orders. We also consider square-free m with all prime divisors congruent to 1 modulo 6: there is a sequenceable group, and hence a complete Latin square, of order 3. m in this case too. This work gives 104 new orders less than 10,000 for which a complete Latin square is known to exist, the smallest of which is 75. © 2014 Elsevier Ltd. Source

Bowen T.A.,Harvard - Smithsonian Center for Astrophysics | Bowen T.A.,Marlboro College | Testa P.,Harvard - Smithsonian Center for Astrophysics | Reeves K.K.,Harvard - Smithsonian Center for Astrophysics
Astrophysical Journal | Year: 2013

We present an analysis of soft X-ray (SXR) and extreme-ultraviolet (EUV) observations of solar flares with an approximate C8 Geostationary Operational Environmental Satellite (GOES) class. Our constraint on peak GOES SXR flux allows for the investigation of correlations between various flare parameters. We show that the duration of the decay phase of a flare is proportional to the duration of its rise phase. Additionally, we show significant correlations between the radiation emitted in the flare rise and decay phases. These results suggest that the total radiated energy of a given flare is proportional to the energy radiated during the rise phase alone. This partitioning of radiated energy between the rise and decay phases is observed in both SXR and EUV wavelengths. Though observations from the EUV Variability Experiment show significant variation in the behavior of individual EUV spectral lines during different C8 events, this work suggests that broadband EUV emission is well constrained. Furthermore, GOES and Atmospheric Imaging Assembly data allow us to determine several thermal parameters (e.g., temperature, volume, density, and emission measure) for the flares within our sample. Analysis of these parameters demonstrate that, within this constrained GOES class, the longer duration solar flares are cooler events with larger volumes capable of emitting vast amounts of radiation. The shortest C8 flares are typically the hottest events, smaller in physical size, and have lower associated total energies. These relationships are directly comparable with several scaling laws and flare loop models. © 2013. The American Astronomical Society. All rights reserved.. Source

Simpore A.,University of Ouagadougou | Simpore A.,National Blood Transfusion Center | Bisseye C.,University of Ouagadougou | Bisseye C.,Universite des Sciences et Techniques de Masuku | And 12 more authors.
Pan African Medical Journal | Year: 2014

Introduction: Due to the existence of a variety of types of non-venereal syphilis caused by the related T. pallidum, regular serological testing such as Rapid Plasma Reagin (RPR) and Chemiluminescent Microparticle Immunoassay Technique (CMIA) are often unable to differentiate venereal syphilis from the non- venereal one, hence, the interest in the use of molecular biology testing for a confirmation diagnosis of syphilis caused by Treponema pallidum subspecies pallidum. Objective: The study is designed to assess the effectiveness of PCR testing and serological methods in the diagnosis of Treponema pallidum subsp pallidum among blood donors in Burkina Faso. Methods: The study included 6375 samples of volunteer blood donors from the regional blood transfusion center of Ouagadougou (CRTS/O). Among samples, 183 positive and 59 negative in RPR were analyzed to detect antibodies anti-T. pallidum subsp pallidum with a immunoassay method (CMIA) and were confirmed using the Polymerase Chain Reaction testing. Results: In RPR, we obtained a prevalence rate of 2.9% (183/6375) for treponematosis. From the 183 RPR+ specimen, 108 (59%) were found CMIA+ and 11 (6%) were confirmed PCR+. While the 59 pattern RPR-; 31 (52.5%) were CMIA + including 3 (5.1%) tested PCR+. Seventy-five (75) samples RPR+/CMIA-; 2 (2.7%) were confirmed positive by PCR. All 28 samples RPR-/CMIA- were confirmed negative by PCR. Conclusion: PCR testing confirmed a low distribution of T. pallidum subsp pallidum in comparison to serological methods. Cross-reactions, existence of non-venereal treponemal or immunological scars could account for the discrepancy between the results obtained. © Abibou Simpore et al. Source

Norsen T.,Marlboro College
Foundations of Physics | Year: 2010

It is shown how, starting with the de Broglie-Bohm pilot-wave theory, one can construct a new theory of the sort envisioned by several of QM's founders: a Theory of Exclusively Local Beables (TELB). In particular, the usual quantum mechanical wave function (a function on a high-dimensional configuration space) is not among the beables posited by the new theory. Instead, each particle has an associated "pilot-wave" field (living in physical space). A number of additional fields (also fields on physical space) maintain what is described, in ordinary quantum theory, as "entanglement." The theory allows some interesting new perspective on the kind of causation involved in pilot-wave theories in general. And it provides also a concrete example of an empirically viable quantum theory in whose formulation the wave function (on configuration space) does not appear-i. e., it is a theory according to which nothing corresponding to the configuration space wave function need actually exist. That is the theory's raison d'etre and perhaps its only virtue. Its vices include the fact that it only reproduces the empirical predictions of the ordinary pilot-wave theory (equivalent, of course, to the predictions of ordinary quantum theory) for spinless non-relativistic particles, and only then for wave functions that are everywhere analytic. The goal is thus not to recommend the TELB proposed here as a replacement for ordinary pilot-wave theory (or ordinary quantum theory), but is rather to illustrate (with a crude first stab) that it might be possible to construct a plausible, empirically viable TELB, and to recommend this as an interesting and perhaps-fruitful program for future research. © 2010 Springer Science+Business Media, LLC. Source

Williams C.C.,University of Massachusetts Amherst | Giavalisco M.,University of Massachusetts Amherst | Cassata P.,Aix - Marseille University | Tundo E.,University of Nottingham | And 18 more authors.
Astrophysical Journal | Year: 2014

We use GOODS and CANDELS images to identify progenitors of massive (M > 1010 M ⊙) compact early-type galaxies (ETGs) at z ∼ 1.6. Because merging and accretion increase the size of the stellar component of galaxies, if the progenitors are among known star-forming galaxies, these must be compact themselves. We select candidate progenitors among compact Lyman-break galaxies at z ∼ 3 on the basis of their mass, star-formation rate (SFR), and central stellar density, and we find that these account for a large fraction of, and possibly all, compact ETGs at z ∼ 1.6. We find that the average far-UV spectral energy distribution (SED) of the candidates is redder than that of the non-candidates, but the optical and mid-IR SED are the same, implying that the redder UV of the candidates is inconsistent with larger dust obscuration and consistent with more evolved (aging) star formation. This is in line with other evidence suggesting that compactness is a sensitive predictor of passivity among high-redshift massive galaxies. We also find that the light distribution of both the compact ETGs and their candidate progenitors does not show any extended "halos" surrounding the compact "core,"both in individual images and in stacks. We argue that this is generally inconsistent with the morphology of merger remnants, even if gas rich, as predicted by N-body simulations. This suggests that the compact ETGs formed via highly dissipative, mostly gaseous accretion of units whose stellar components are very small and undetected in the Hubble Space Telescope images, with their stellar mass assembling in situ, and that they have not experienced any major merging until the epoch of observations at z ∼ 1.6. © 2014. The American Astronomical Society. All rights reserved. Source

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