Detection of H2O and evidence for TiO/VO in an ultra hot exoplanet atmosphere

This is the author accepted manuscript. The final version is available from American Astronomical Society via the DOI in this recordWe present a primary transit observation for the ultra hot (Teq 2400 K) gas giant expolanetWASP-121b, made using the Hubble Space Telescope Wide Field Camera 3 in spectroscopic mode across the 1.12{1.64 m wavelength range. The 1.4 m water absorption band is detected at high con dence (5:4 ) in the planetary atmosphere. We also reanalyze ground-based photometric lightcurves taken in the B, r0, and z0 lters. Signi cantly deeper transits are measured in these optical bandpasses relative to the near-infrared wavelengths. We conclude that scattering by high-altitude haze alone is unlikely to account for this di erence, and instead interpret it as evidence for titanium oxide and vanadium oxide absorption. Enhanced opacity is also inferred across the 1:12{1:3 m wavelength range, possibly due to iron hydride absorption. If con rmed, WASP-121b will be the rst exoplanet with titanium oxide, vanadium oxide, and iron hydride detected in transmission. The latter are important species in M/L dwarfs, and their presence is likely to have a signi cant e ect on the overall physics and chemistry of the atmosphere, including the production of a strong thermal inversionThe research leading to these results has received funding from the European Research Council under the European Union Seventh Framework Program (FP7/2007-2013) ERC grant agreement no. 336792

History of clinical transplantation

The emergence of transplantation has seen the development of increasingly potent immunosuppressive agents, progressively better methods of tissue and organ preservation, refinements in histocompatibility matching, and numerous innovations is surgical techniques. Such efforts in combination ultimately made it possible to successfully engraft all of the organs and bone marrow cells in humans. At a more fundamental level, however, the transplantation enterprise hinged on two seminal turning points. The first was the recognition by Billingham, Brent, and Medawar in 1953 that it was possible to induce chimerism-associated neonatal tolerance deliberately. This discovery escalated over the next 15 years to the first successful bone marrow transplantations in humans in 1968. The second turning point was the demonstration during the early 1960s that canine and human organ allografts could self-induce tolerance with the aid of immunosuppression. By the end of 1962, however, it had been incorrectly concluded that turning points one and two involved different immune mechanisms. The error was not corrected until well into the 1990s. In this historical account, the vast literature that sprang up during the intervening 30 years has been summarized. Although admirably documenting empiric progress in clinical transplantation, its failure to explain organ allograft acceptance predestined organ recipients to lifetime immunosuppression and precluded fundamental changes in the treatment policies. After it was discovered in 1992 that long-surviving organ transplant recipient had persistent microchimerism, it was possible to see the mechanistic commonality of organ and bone marrow transplantation. A clarifying central principle of immunology could then be synthesized with which to guide efforts to induce tolerance systematically to human tissues and perhaps ultimately to xenografts

VLT/FORS2 comparative transmission spectroscopy II: confirmation of a cloud-deck and Rayleigh scattering in WASP-31b, but no potassium?

This is the author accepted manuscript. The final version is available from OUP via the DOI in this record.We present transmission spectroscopy of the hot-Jupiter WASP-31b using FORS2 on the VLT during two primary transits. The observations cover a wavelength range of ≈400–840 nm. The light curves are corrupted by significant systematics, but these were to first order invariant with wavelength and could be removed using a commonmode correction derived from the white light curves. We reach a precision in the transit depth of ≈140 ppm in 15 nm bins, although the precision varies significantly over the wavelength range. Our FORS2 observations confirm the cloud-deck previously inferred using HST/STIS. We also re-analyse the HST/STIS data using a Gaussian process model, finding excellent agreement with earlier measurements. We reproduce the Rayleigh scattering signature at short wavelengths (. 5300 ˚A) and the cloud-deck at longer wavelengths. However, our FORS2 observations appear to rule out the large potassium feature previously detected using STIS, yet it is recovered from the HST/STIS data, although with reduced amplitude and significance (≈ 2.5σ). The discrepancy between our results and the earlier STIS detection of potassium (≈ 4.3σ) is either a result of telluric contamination of the ground-based observations, or an underestimate of the uncertainties for narrow-band features in HST/STIS when using linear basis models to account for the systematics. Our results further demonstrate the use of ground-based multi-object spectrographs for the study of exoplanet atmospheres, and highlight the need for caution in our interpretation of narrow-band features in low-resolution spectra of hot-Jupiters.This work is based on observations collected at the European Organisation for Astronomical Research in the Southern Hemisphere under ESO programme 096.C-0765. N. P. G. gratefully acknowledges support from the Royal Society in the form of a University Research Fellowship. N. N, D. K. S, and T. M. E. acknowledge funding from the European Research Council under the European Unions Seventh Framework Programme (FP7/2007-2013) / ERC grant agreement no. 336792. J. K. B. is supported by a Royal Astronomical Society Research Fellowship. P.A.W. acknowledges the support of the French Agence Nationale de la Recherche (ANR), under program ANR-12-BS05-0012 ‘Exo-Atmos’. We are grateful to the developers of the NumPy, SciPy, Matplotlib, iPython and Astropy packages, which were used extensively in this work (Jones et al. 01 ; Hunter 2007; P´erez & Granger 2007; Astropy Collaboration et al. 2013)

In vitro modulation of inflammatory cytokine and IgG levels by extracts of Perna canaliculus

BACKGROUND: Inflammation is a predominant characteristic of autoimmune diseases which is characterized by the increased expression of pro-inflammatory cytokines. Soon to be published work from our laboratory has shown that ingestion of Perna canaliculus prevents the development of autoimmune diseases such as Systemic Lupus Erythematosus and rheumatoid arthritis in laboratory animals. The current paper attempts to illustrate how Perna can alleviate inflammation by modulating inflammatory cytokines, cyclooxygenase enzymes and Immunoglobulin-G (IgG) levels. METHODS: In the present study, hydrochloric acid [HCl] and Tween-20 were used to develop extracts of Perna. These extracts were assayed for protein content. Increasing concentrations of these extracts were then tested in cell culture for modulation of inflammatory cytokine, cyclooxygenase enzymes and IgG levels. Parallel tests were run using an available glycogen extract of Perna as a comparison to our in-house laboratory preparations. RESULTS: Tween-20 Perna extracts were found to be more stable and less toxic in cell culture than HCl digest of Perna. They also assayed higher in protein content that HCl extracts. Although both extracts inhibited IgG production in V2E9 hybridomas, Tween-20 extracts were more consistent in IgG suppression than HCl extracts. Overall Tween-20 extracts effectively decreased levels of TNF-α, IL-1, IL-2 and IL-6 as observed using cytokine bioassays. Twenty micrograms of Tween-20 Perna extracts induced such significant decreases in inflammatory cytokine production that when tested on sensitive cell lines, they very nearly abolished the decrease in viability induced by these cytokines. Tween-20 extracts effectively inhibited both COX-1 and COX-2 cyclooxygenase activity. As a comparison, the glycogen extract also demonstrated a similar though weaker effect on COX-1 and COX-2 enzymes. The active components of both extracts (Tween-20 and glycogen) were observed to possess molecular weights above 100 kDa. Although the anti-cytokine activity of the Tween-20 extract was destroyed by Proteinase-K treatment, the anti-COX-1 and anti-COX-2 activity of both the extracts were not sensitive to protease treatment. CONCLUSION: We have successfully demonstrated modulation in the levels of inflammatory cytokines, cyclooxygenase enzymes and immunoglobulins by our in-house laboratory preparations of Perna canaliculus, whereby suggesting an immunomodulatory role of Perna canaliculus in regulating inflammation

Predictive Modelling Of Temperature And Water Activity (Solutes) On The In Vitro Radial Growth Of Botrytis Cinerea Pers

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El corregidor de indios, la corrupción y el estado virreinal en Perú, 1580-1630

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The Nature of Notebooks: How Enlightenment Schoolchildren Transformed the Tabula Rasa

John Locke's comparison of the mind to a blank piece of paper, the tabula rasa, was one of the most recognizable metaphors of the British Enlightenment. Though scholars embrace its impact on the arts, humanities, natural sciences, and social sciences, they seldom consider why the metaphor was so successful. Concentrating on the notebooks made and used by the schoolchildren of Enlightenment Scotland, this essay contends that the answer lies in the material and visual conditions that gave rise to the metaphor's usage. By the time students had finished school, they had learned to conceptualize the pages, the script, and the figures of their notebooks as indispensable learning tools that could be manipulated by scores of adaptable folding, writing, and drawing techniques. In this article, I reveal that historicizing the epistemology and manipulability of student manuscript culture makes it possible to see that the success of Locke's metaphor was founded on its appeal to everyday note-keeping activities performed by British schoolchildren