Economics of Cattle Feeding Systems for West Texas.

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The Transitional Stripped-Envelope SN 2008ax: Spectral Evolution and Evidence for Large Asphericity

Supernova (SN) 2008ax in NGC 4490 was discovered within hours after shock breakout, presenting the rare opportunity to study a core-collapse SN beginning with the initial envelope-cooling phase immediately following shock breakout. We present an extensive sequence of optical and near-infrared spectra, as well as three epochs of optical spectropolarimetry. Our initial spectra, taken two days after shock breakout, are dominated by hydrogen Balmer lines at high velocity. However, by maximum light, He I lines dominated the optical and near-infrared spectra, which closely resembled those of normal Type Ib supernovae (SNe Ib) such as SN 1999ex. This spectroscopic transition defines Type IIb supernovae, but the strong similarity of SN 2008ax to normal SNe Ib beginning near maximum light, including an absorption feature near 6270A due to H-alpha at high velocities, suggests that many objects classified as SNe Ib in the literature may have ejected similar amounts of hydrogen as SN 2008ax, roughly a few x 0.01 M_sun. Early-time spectropolarimetry (6 and 9 days after shock breakout) revealed strong line polarization modulations of 3.4% across H-alpha, indicating the presence of large asphericities in the outer ejecta. The continuum shares a common polarization angle with the hydrogen, helium, and oxygen lines, while the calcium and iron absorptions are oriented at different angles. This is clear evidence of deviations from axisymmetry even in the outer ejecta. Intrinsic continuum polarization of 0.64% only nine days after shock breakout shows that the outer layers of the ejecta were quite aspherical. A single epoch of late-time spectropolarimetry, as well as the shapes of the nebular line profiles, demonstrate that asphericities extended from the outermost layers all the way down to the center of this SN. [Abridged]Comment: 24 pages, 21 figures, 4 tables, appendix, minor revisions to match version accepted by Ap

Noise parametric identification and whitening for LIGO 40-meter interferometer data

We report the analysis we made on data taken by Caltech 40-meter prototype interferometer to identify the noise power spectral density and to whiten the sequence of noise. We concentrate our study on data taken in November 1994, in particular we analyzed two frames of data: the 18nov94.2.frame and the 19nov94.2.frame. We show that it is possible to whiten these data, to a good degree of whiteness, using a high order whitening filter. Moreover we can choose to whiten only restricted band of frequencies around the region we are interested in, obtaining a higher level of whiteness.Comment: 11 pages, 15 figures, accepted for publication by Physical Review

The kinematics and chemical stratification of the Type Ia supernova remnant 0519-69.0

We present an analysis of the XMM-Newton and Chandra X-ray data of the young Type Ia supernova remnant 0519-69.0 in the Large Magellanic Cloud. We used data from both the Chandra ACIS and XMM-Newton EPIC-MOS instruments, and high resolution X-ray spectra obtained with the XMM-Newton Reflection Grating Spectrometer. The Chandra data show that there is a radial stratification of oxygen, intermediate mass elements and iron, with the emission from more massive elements more toward the center. Using a deprojection technique we measure a forward shock radius of 4.0(3) pc and a reverse shock radius of 2.7(4) pc. We took the observed stratification of the shocked ejecta into account in the modeling of the X-ray spectra with multi-component NEI models, with the components corresponding to layers dominated by one or two elements. An additional component was added in order to represent the ISM, which mostly contributed to the continuum emission. This model fits the data well, and was also employed to characterize the spectra of distinct regions extracted from the Chandra data. From our spectral analysis we find that the fractional masses of shocked ejecta for the most abundant elements are: M(O)=32%, M(Si/S)=7%/5%, M(Ar+Ca)=1%, and M(Fe) = 55%. From the continuum component we derive a circumstellar density of nH= 2.4(2)/cm^3. This density, together with the measurements of the forward and reverse shock radii suggest an age of 450+/-200 yr,somewhat lower than, but consistent with the estimate based on the optical light echo (600+/-200 yr). From the RGS spectra we measured a Doppler broadening of sigma=1873+/-50 km/s, from implying a forward shock velocity of vS = 2770+/-500 km/s. We discuss the results in the context of single degenerate explosion models, using semi-analytical and numerical modeling, and compare the characteristics of 0519-69.0 with those of other Type Ia supernova remnants.Comment: Astronomy and Astrophysics in press. This version is the A&A accepted version, which contains improved figures and an extended discussion sectio

Cryo-EM structural analysis of FADD:Caspase-8 complexes defines the catalytic dimer architecture for co-ordinated control of cell fate.

Regulated cell death is essential in development and cellular homeostasis. Multi-protein platforms, including the Death-Inducing Signaling Complex (DISC), co-ordinate cell fate via a core FADD:Caspase-8 complex and its regulatory partners, such as the cell death inhibitor c-FLIP. Here, using electron microscopy, we visualize full-length procaspase-8 in complex with FADD. Our structural analysis now reveals how the FADD-nucleated tandem death effector domain (tDED) helical filament is required to orientate the procaspase-8 catalytic domains, enabling their activation via anti-parallel dimerization. Strikingly, recruitment of c-FLIPS into this complex inhibits Caspase-8 activity by altering tDED triple helix architecture, resulting in steric hindrance of the canonical tDED Type I binding site. This prevents both Caspase-8 catalytic domain assembly and tDED helical filament elongation. Our findings reveal how the plasticity, composition and architecture of the core FADD:Caspase-8 complex critically defines life/death decisions not only via the DISC, but across multiple key signaling platforms including TNF complex II, the ripoptosome, and RIPK1/RIPK3 necrosome

Cryo-EM structural analysis of FADD:Caspase-8 complexes defines the catalytic dimer architecture for co-ordinated control of cell fate.

Regulated cell death is essential in development and cellular homeostasis. Multi-protein platforms, including the Death-Inducing Signaling Complex (DISC), co-ordinate cell fate via a core FADD:Caspase-8 complex and its regulatory partners, such as the cell death inhibitor c-FLIP. Here, using electron microscopy, we visualize full-length procaspase-8 in complex with FADD. Our structural analysis now reveals how the FADD-nucleated tandem death effector domain (tDED) helical filament is required to orientate the procaspase-8 catalytic domains, enabling their activation via anti-parallel dimerization. Strikingly, recruitment of c-FLIPS into this complex inhibits Caspase-8 activity by altering tDED triple helix architecture, resulting in steric hindrance of the canonical tDED Type I binding site. This prevents both Caspase-8 catalytic domain assembly and tDED helical filament elongation. Our findings reveal how the plasticity, composition and architecture of the core FADD:Caspase-8 complex critically defines life/death decisions not only via the DISC, but across multiple key signaling platforms including TNF complex II, the ripoptosome, and RIPK1/RIPK3 necrosome

Does oral sodium bicarbonate therapy improve function and quality of life in older patients with chronic kidney disease and low-grade acidosis (the BiCARB trial)? Study protocol for a randomized controlled trial

Date of acceptance: 01/07/2015 © 2015 Witham et al. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly credited. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated. Acknowledgements UK NIHR HTA grant 10/71/01. We acknowledge the financial support of NHS Research Scotland in conducting this trial.Peer reviewedPublisher PD

Global and local space properties of stream programs

The original publication is available at www.springerlink.comInternational audienceIn this paper, we push forward the approach proposed in [1] aiming at studying semantic interpretation criteria for the purpose of ensuring safety and complexity properties of programs working on streams. The paper improves the previous results by considering global and local upper bounds properties of both theoretical and practical interests guaranteeing that the size of each output stream element is bounded by a function in the maximal size of the input stream elements. Moreover, in contrast to previous studies, these properties also apply to a wide class of stream definitions, that is functions that do not have streams in the input but produce an output stream

Etno-muzeji na otvorenom i zaštita spomenika kulture

Formation of the death-inducing signaling complex (DISC) initiates extrinsic apoptosis. Caspase-8 and its regulator cFLIP control death signaling by binding to death-receptor-bound FADD. By elucidating the function of the caspase-8 homolog, caspase-10, we discover that caspase-10 negatively regulates caspase-8-mediated cell death. Significantly, we reveal that caspase-10 reduces DISC association and activation of caspase-8. Furthermore, we extend our co-operative/hierarchical binding model of caspase-8/cFLIP and show that caspase-10 does not compete with caspase-8 for binding to FADD. Utilizing caspase-8-knockout cells, we demonstrate that caspase-8 is required upstream of both cFLIP and caspase-10 and that DISC formation critically depends on the scaffold function of caspase-8. We establish that caspase-10 rewires DISC signaling to NF-κB activation/cell survival and demonstrate that the catalytic activity of caspase-10, and caspase-8, is redundant in gene induction. Thus, our data are consistent with a model in which both caspase-10 and cFLIP coordinately regulate CD95L-mediated signaling for death or survival

Genetic Diversity Enhances Restoration Success by Augmenting Ecosystem Services

Disturbance and habitat destruction due to human activities is a pervasive problem in near-shore marine ecosystems, and restoration is often used to mitigate losses. A common metric used to evaluate the success of restoration is the return of ecosystem services. Previous research has shown that biodiversity, including genetic diversity, is positively associated with the provision of ecosystem services. We conducted a restoration experiment using sources, techniques, and sites similar to actual large-scale seagrass restoration projects and demonstrated that a small increase in genetic diversity enhanced ecosystem services (invertebrate habitat, increased primary productivity, and nutrient retention). In our experiment, plots with elevated genetic diversity had plants that survived longer, increased in density more quickly, and provided more ecosystem services (invertebrate habitat, increased primary productivity, and nutrient retention). We used the number of alleles per locus as a measure of genetic diversity, which, unlike clonal diversity used in earlier research, can be applied to any organism. Additionally, unlike previous studies where positive impacts of diversity occurred only after a large disturbance, this study assessed the importance of diversity in response to potential environmental stresses (high temperature, low light) along a water–depth gradient. We found a positive impact of diversity along the entire depth gradient. Taken together, these results suggest that ecosystem restoration will significantly benefit from obtaining sources (transplants or seeds) with high genetic diversity and from restoration techniques that can maintain that genetic diversity