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    The integral monodromy of hyperelliptic and trielliptic curves

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    We compute the \integ/\ell and \integ_\ell monodromy of every irreducible component of the moduli spaces of hyperelliptic and trielliptic curves. In particular, we provide a proof that the \integ/\ell monodromy of the moduli space of hyperelliptic curves of genus gg is the symplectic group \sp_{2g}(\integ/\ell). We prove that the \integ/\ell monodromy of the moduli space of trielliptic curves with signature (r,s)(r,s) is the special unitary group \su_{(r,s)}(\integ/\ell\tensor\integ[\zeta_3])

    Radiative capture of protons by deuterons

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    The differential cross section for radiative capture of protons by deuterons is calculated using different realistic NN interactions. We compare our results with the available experimental data below Ex=20MeVE_x = 20 MeV. Excellent agreement is found when taking into account meson exchange currents, dipole and quadrupole contributions, and the full initial state interaction. There is only a small difference between the magnitudes of the cross sections for the different potentials considered. The angular distributions, however, are practically potential independent.Comment: 4 pages (twocolumn), 4 postscript figures included, submitted for publication, revised versio

    The railroad switch effect of seasonally reversing currents on the Bay of Bengal high salinity core

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    The Southwest Monsoon Current (SMC) flows eastward from the Arabian Sea into the Bay of Bengal (BoB) during summer, advecting a core of high salinity water. This high salinity core has been linked with Arabian Sea High Salinity Water that is presumed to enter the BoB directly from the Arabian Sea via the SMC. Here we show that the high salinity core originates primarily from the western equatorial Indian Ocean, reaching the BoB via the Somali Current, the Equatorial Undercurrent and the SMC. Years with anomalously saline high salinity cores are linked with the East Africa Coastal Current and the Somali Current winter convergence, and an anomalously strong Equatorial Undercurrent. Seasonal reversals that occur at the Somali Current and SMC junctions act as 'railroad switches' diverting water masses to different basins in the northern Indian Ocean. Interannual fluctuations of the Equatorial Undercurrent are linked to wind stress and El Nino

    Neoliberalisation and 'lad cultures' in higher education

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    This paper links HE neoliberalisation and ‘lad cultures’, drawing on interviews and focus groups with women students. We argue that retro-sexist ‘laddish’ forms of masculine competitiveness and misogyny have been reshaped by neoliberal rationalities to become modes of consumerist sexualised audit. We also suggest that neoliberal frameworks scaffold an individualistic and adversarial culture among young people that interacts with perceived threats to men’s privilege and intensifies attempts to put women in their place through misogyny and sexual harassment. Furthermore, ‘lad cultures’, sexism and sexual harassment in higher education may be invisibilised by institutions to preserve marketability in a neoliberal context. In response, we ask if we might foster dialogue and partnership between feminist and anti-marketisation politics

    Discovery of hybrid γ\gamma Dor and δ\delta Sct pulsations in BD+18 4914 through MOST spacebased photometry

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    We present a total of 57 days of contiguous, high-cadence photometry (14 days in 2004 and 43 in 2005) of the star BD+18 4914 obtained with the MOST satellite. We detect 16 frequencies down to a signal-to-noise of 3.6 (amplitude \~ 0.5 mmag). Six of these are less than 3 cycles/day, and the other ten are between 7 and 16 cycles/day. We intrepret the low frequencies as g-mode γ\gamma Doradus-type pulsations and the others as δ\delta Scuti-type p-modes, making BD+18 4914 one of the few known hybrid pulsators of its class. If the g-mode pulsations are high-overtone non-radial modes with identical low degree l, we can assign a unique mode classification of n={12, 20, 21, 22, 31, 38} based on the frequency ratio method.Comment: 11 pages, 3 figure, to appear in Communications in Asteroseismology v. 14

    Signaling via interleukin-4, receptor alpha chain is required for successful vaccination against schistosomiasis in BALB/c mice

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    Radiation-attenuated (RA) schistosome larvae are potent stimulators of innate immune responses at the skin site of exposure (pinna) that are likely to be important factors in the development of Th1-mediated protective immunity. In addition to causing an influx of neutrophils, macrophages, and dendritic cells (DCs) into the dermis, RA larvae induced a cascade of chemokine and cytokine secretion following in vitro culture of pinna biopsy samples. While macrophage inflammatory protein 1 and interleukin-1 (IL-1) were produced transiently within the first few days, the Th1-promoting cytokines IL-12 and IL-18 were secreted at high levels until at least day 14. Assay of C3H/HeJ mice confirmed that IL-12 secretion was not due to lipopolysaccharide contaminants binding Toll-like receptor 4. Significantly, IL-12 p40 secretion was sustained in pinnae from vaccinated mice but not in those from nonprotected infected mice. In contrast, IL-10 was produced from both vaccinated and infected mice. This cytokine regulates IL-12-associated dermal inflammation, since in vaccinated IL-10/ mice, pinna thickness was greatly increased concurrent with elevated levels of IL-12 p40. A significant number of IL-12 p40 cells were detected as emigrants from in vitro-cultured pinnae, and most were within a population of rare large granular cells that were Ia, consistent with their being antigen-presenting cells. Labeling of IL-12 cells for CD11c, CD205, CD8, CD11b, and F4/80 indicated that the majority were myeloid DCs, although a proportion were CD11c F4/80, suggesting that macrophages were an additional source of IL-12 in the skin

    HI in NGC 5433 and its Environment: High-Latitude Emission in a Small Galaxy Group

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    We present HI synthesis maps of the edge-on starburst NGC 5433 and its environment, obtained with the VLA in its C and D configurations. The observations and spectral model residuals of the main disc emission in NGC 5433 reveal 3 extraplanar features. We associate 2 of these features with coherent extraplanar extensions across multiple spectral channels in our data, including a complete loop in position-velocity space. Interpreting the latter as an expanding shell we derive a corresponding input energy of 2 x 10^54 ergs, comparable to that for the largest supershells found in the Galaxy and those in other edge-on systems. NGC 5433 is in a richer environment than previously thought. We confirm that KUG 1359+326 is a physical companion to NGC 5433 and find two new faint companions, both with Minnesota Automated Plate Scanner identifications, that we label SIS-1 and SIS-2. Including the more distant IC 4357, NGC 5433 is the dominant member of a group of at least 5 galaxies, spanning over 750 kpc in a filamentary structure. A variety of evidence suggests that interactions are occurring in this group. While a number of underlying mechanisms are consistent with the morphology of the high-latitude features in NGC 5433, we argue that environmental effects may play a role in their generation.Comment: 18 pages including 10 figures. Accepted for publication in MNRAS. For higher resolution Fig. 1, see http://www.astro.cornell.edu/~spekkens/papers/ v2: Proof-corrected cop

    Testing alternative hypotheses for the decline of cichlid fish in Lake Victoria using fish tooth time series from sediment cores.

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    Lake Victoria is well known for its high diversity of endemic fish species and provides livelihoods for millions of people. The lake garnered widespread attention during the twentieth century as major environmental and ecological changes modified the fish community with the extinction of approximately 40% of endemic cichlid species by the 1980s. Suggested causal factors include anthropogenic eutrophication, fishing, and introduced non-native species but their relative importance remains unresolved, partly because monitoring data started in the 1970s when changes were already underway. Here, for the first time, we reconstruct two time series, covering the last approximately 200 years, of fish assemblage using fish teeth preserved in lake sediments. Two sediment cores from the Mwanza Gulf of Lake Victoria, were subsampled continuously at an intra-decadal resolution, and teeth were identified to major taxa: Cyprinoidea, Haplochromini, Mochokidae and Oreochromini. None of the fossils could be confidently assigned to non-native Nile perch. Our data show significant decreases in haplochromine and oreochromine cichlid fish abundances that began long before the arrival of Nile perch. Cyprinoids, on the other hand, have generally been increasing. Our study is the first to reconstruct a time series of any fish assemblage in Lake Victoria extending deeper back in time than the past 50 years, helping shed light on the processes underlying Lake Victoria's biodiversity loss
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