3,504 research outputs found

    Early Stuart Courts Leet: Still Needful and Useful

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    Research of the past twenty years has corrected the view that post-medieval leets were decadent and has demonstrated that many Tudor leets remained active and powerful. This article attempts to demonstrate that several early Stuart leets were not "decadents", but still exercised jurisdiction over many misdemeanors and satisfied the desire and need for local, inexpensive, neighbourly justice. Given the local character of early Stuart society, and the dependence of justices upon inferior officers, courts leet were needful and useful.La recherche des vingt dernières années a modifié la vision traditionnelle selon laquelle les courts 1eet auraient sombré dans la décadence pendant la période moderne; elle a démontré que sous les Tudors, les courts 1eet étaient actives et puissantes. Cet article cherche à prouver que sous les Stuarts, un certain nombre de courts 1eet n'étaient pas décadentes, mais continuaient à exercer leur juridiction à l'encontre d'un grand nombre de délits et satisfaisaient le besoin pour une justice locale et peu coûteuse. Compte tenu de la décentralisation de l'Angleterre des Stuarts et de la dépendance des juges envers leurs subordonnés, les courts 1eet étaient nécéssaires et utiles

    An engineered cardiac reporter cell line identifies human embryonic stem cell-derived myocardial precursors.

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    Unlike some organs, the heart is unable to repair itself after injury. Human embryonic stem cells (hESCs) grow and divide indefinitely while maintaining the potential to develop into many tissues of the body. As such, they provide an unprecedented opportunity to treat human diseases characterized by tissue loss. We have identified early myocardial precursors derived from hESCs (hMPs) using an α-myosin heavy chain (αMHC)-GFP reporter line. We have demonstrated by immunocytochemistry and quantitative real-time PCR (qPCR) that reporter activation is restricted to hESC-derived cardiomyocytes (CMs) differentiated in vitro, and that hMPs give rise exclusively to muscle in an in vivo teratoma formation assay. We also demonstrate that the reporter does not interfere with hESC genomic stability. Importantly, we show that hMPs give rise to atrial, ventricular and specialized conduction CM subtypes by qPCR and microelectrode array analysis. Expression profiling of hMPs over the course of differentiation implicate Wnt and transforming growth factor-β signaling pathways in CM development. The identification of hMPs using this αMHC-GFP reporter line will provide important insight into the pathways regulating human myocardial development, and may provide a novel therapeutic reagent for the treatment of cardiac disease

    Heat shock factor 1 regulates lifespan as distinct from disease onset in prion disease

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    Prion diseases are fatal, transmissible, neurodegenerative diseases caused by the misfolding of the prion protein (PrP). At present, the molecular pathways underlying prion-mediated neurotoxicity are largely unknown. We hypothesized that the transcriptional regulator of the stress response, heat shock factor 1 (HSF1), would play an important role in prion disease. Uninoculated HSF1 knockout (KO) mice used in our study do not show signs of neurodegeneration as assessed by survival, motor performance, or histopathology. When inoculated with Rocky Mountain Laboratory (RML) prions HSF1 KO mice had a dramatically shortened lifespan, succumbing to disease ≈20% faster than controls. Surprisingly, both the onset of home-cage behavioral symptoms and pathological alterations occurred at a similar time in HSF1 KO and control mice. The accumulation of proteinase K (PK)-resistant PrP also occurred with similar kinetics and prion infectivity accrued at an equal or slower rate. Thus, HSF1 provides an important protective function that is specifically manifest after the onset of behavioral symptoms of prion disease

    Evidence of strong quasar feedback in the early Universe

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    Most theoretical models invoke quasar driven outflows to quench star formation in massive galaxies, this feedback mechanism is required to account for the population of old and passive galaxies observed in the local universe. The discovery of massive, old and passive galaxies at z=2, implies that such quasar feedback onto the host galaxy must have been at work very early on, close to the reionization epoch. We have observed the [CII]158um transition in SDSSJ114816.64+525150.3 that, at z=6.4189, is one of the most distant quasars known. We detect broad wings of the line tracing a quasar-driven massive outflow. This is the most distant massive outflow ever detected and is likely tracing the long sought quasar feedback, already at work in the early Universe. The outflow is marginally resolved on scales of about 16 kpc, implying that the outflow can really affect the whole galaxy, as required by quasar feedback models. The inferred outflow rate, dM/dt > 3500 Msun/yr, is the highest ever found. At this rate the outflow can clean the gas in the host galaxy, and therefore quench star formation, in a few million years.Comment: 5 pages, 3 figures, accepted for publication in MNRAS Letter

    The Cyborg Astrobiologist: Testing a Novelty-Detection Algorithm on Two Mobile Exploration Systems at Rivas Vaciamadrid in Spain and at the Mars Desert Research Station in Utah

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    (ABRIDGED) In previous work, two platforms have been developed for testing computer-vision algorithms for robotic planetary exploration (McGuire et al. 2004b,2005; Bartolo et al. 2007). The wearable-computer platform has been tested at geological and astrobiological field sites in Spain (Rivas Vaciamadrid and Riba de Santiuste), and the phone-camera has been tested at a geological field site in Malta. In this work, we (i) apply a Hopfield neural-network algorithm for novelty detection based upon color, (ii) integrate a field-capable digital microscope on the wearable computer platform, (iii) test this novelty detection with the digital microscope at Rivas Vaciamadrid, (iv) develop a Bluetooth communication mode for the phone-camera platform, in order to allow access to a mobile processing computer at the field sites, and (v) test the novelty detection on the Bluetooth-enabled phone-camera connected to a netbook computer at the Mars Desert Research Station in Utah. This systems engineering and field testing have together allowed us to develop a real-time computer-vision system that is capable, for example, of identifying lichens as novel within a series of images acquired in semi-arid desert environments. We acquired sequences of images of geologic outcrops in Utah and Spain consisting of various rock types and colors to test this algorithm. The algorithm robustly recognized previously-observed units by their color, while requiring only a single image or a few images to learn colors as familiar, demonstrating its fast learning capability.Comment: 28 pages, 12 figures, accepted for publication in the International Journal of Astrobiolog

    An integrative computational model for intestinal tissue renewal

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    Objectives\ud \ud The luminal surface of the gut is lined with a monolayer of epithelial cells that acts as a nutrient absorptive engine and protective barrier. To maintain its integrity and functionality, the epithelium is renewed every few days. Theoretical models are powerful tools that can be used to test hypotheses concerning the regulation of this renewal process, to investigate how its dysfunction can lead to loss of homeostasis and neoplasia, and to identify potential therapeutic interventions. Here we propose a new multiscale model for crypt dynamics that links phenomena occurring at the subcellular, cellular and tissue levels of organisation.\ud \ud Methods\ud \ud At the subcellular level, deterministic models characterise molecular networks, such as cell-cycle control and Wnt signalling. The output of these models determines the behaviour of each epithelial cell in response to intra-, inter- and extracellular cues. The modular nature of the model enables us to easily modify individual assumptions and analyse their effects on the system as a whole.\ud \ud Results\ud \ud We perform virtual microdissection and labelling-index experiments, evaluate the impact of various model extensions, obtain new insight into clonal expansion in the crypt, and compare our predictions with recent mitochondrial DNA mutation data. \ud \ud Conclusions\ud \ud We demonstrate that relaxing the assumption that stem-cell positions are fixed enables clonal expansion and niche succession to occur. We also predict that the presence of extracellular factors near the base of the crypt alone suffices to explain the observed spatial variation in nuclear beta-catenin levels along the crypt axis

    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

    Electronic dielectric constants of insulators by the polarization method

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    We discuss a non-perturbative, technically straightforward, easy-to-use, and computationally affordable method, based on polarization theory, for the calculation of the electronic dielectric constant of insulating solids at the first principles level. We apply the method to GaAs, AlAs, InN, SiC, ZnO, GaN, AlN, BeO, LiF, PbTiO3_3, and CaTiO3_3. The predicted \einf's agree well with those given by Density Functional Perturbation Theory (the reference theoretical treatment), and they are generally within less than 10 % of experiment.Comment: RevTeX 4 pages, 2 ps figure

    Testing the universality of star formation - II. Comparing separation distributions of nearby star-forming regions and the field

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    We have measured the multiplicity fractions and separation distributions of seven young star-forming regions using a uniform sample of young binaries. Both the multiplicity fractions and separation distributions are similar in the different regions. A tentative decline in the multiplicity fraction with increasing stellar density is apparent, even for binary systems with separations too close (19-100au) to have been dynamically processed. The separation distributions in the different regions are statistically indistinguishable over most separation ranges, and the regions with higher densities do not exhibit a lower proportion of wide (300-620au) relative to close (62-300au) binaries as might be expected from the preferential destruction of wider pairs. Only the closest (19-100au) separation range, which would be unaffected by dynamical processing, shows a possible difference in separation distributions between different regions. The combined set of young binaries, however, shows a distinct difference when compared to field binaries, with a significant excess of close (19-100au) systems among the younger binaries. Based on both the similarities and differences between individual regions, and between all seven young regions and the field, especially over separation ranges too close to be modified by dynamical processing, we conclude that multiple star formation is not universal and, by extension, the star formation process is not universal.Comment: accepted for publication in MNRA
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