Area products for stationary black hole horizons

Area products for multi-horizon stationary black holes often have intriguing properties, and are often (though not always) independent of the mass of the black hole itself (depending only on various charges, angular momenta, and moduli). Such products are often formulated in terms of the areas of inner (Cauchy) horizons and outer (event) horizons, and sometimes include the effects of unphysical "virtual" horizons. But the conjectured mass-independence sometimes fails. Specifically, for the Schwarzschild-de Sitter [Kottler] black hole in (3+1) dimensions it is shown by explicit exact calculation that the product of event horizon area and cosmological horizon area is not mass independent. (Including the effect of the third "virtual" horizon does not improve the situation.) Similarly, in the Reissner-Nordstrom-anti-de Sitter black hole in (3+1) dimensions the product of inner (Cauchy) horizon area and event horizon area is calculated (perturbatively), and is shown to be not mass independent. That is, the mass-independence of the product of physical horizon areas is not generic. In spherical symmetry, whenever the quasi-local mass m(r) is a Laurent polynomial in aerial radius, r=sqrt{A/4\pi}, there are significantly more complicated mass-independent quantities, the elementary symmetric polynomials built up from the complete set of horizon radii (physical and virtual). Sometimes it is possible to eliminate the unphysical virtual horizons, constructing combinations of physical horizon areas that are mass independent, but they tend to be considerably more complicated than the simple products and related constructions currently being mooted in the literature.Comment: V1: 16 pages; V2: 9 pages (now formatted in PRD style). Minor change in title. Extra introduction, background, discussion. Several additional references; other references updated. Minor typos fixed. This version accepted for publication in PRD; V3: Minor typos fixed. Published versio

Community effects in regulation of translation

Certain forms of translational regulation, and translation itself, rely on long-range interactions between proteins bound to the different ends of mRNAs. A widespread assumption is that such interactions occur only in cis, between the two ends of a single transcript. However, certain translational regulatory defects of the Drosophila oskar (osk) mRNA can be rescued in trans. We proposed that inter-transcript interactions, promoted by assembly of the mRNAs in particles, allow regulatory elements to act in trans. Here we confirm predictions of that model and show that disruption of PTB-dependent particle assembly inhibits rescue in trans. Communication between transcripts is not limited to different osk mRNAs, as regulation imposed by cis-acting elements embedded in the osk mRNA spreads to gurken mRNA. We conclude that community effects exist in translational regulation

Recent Developments in Yeast Aging

In the last decade, research into the molecular determinants of aging has progressed rapidly and much of this progress can be attributed to studies in invertebrate eukaryotic model organisms. Of these, single-celled yeast is the least complicated and most amenable to genetic and molecular manipulations. Supporting the use of this organism for aging research, increasing evidence has accumulated that a subset of pathways influencing longevity in yeast are conserved in other eukaryotes, including mammals. Here we briefly outline aging in yeast and describe recent findings that continue to keep this “simple” eukaryote at the forefront of aging research

Predicting the consequences of indiscriminate poaching on the population persistence of a non-target species of conservation concern

Illegal animal hunting, a contributor to biodiversity loss, occurs along a relative selectivity spectrum from indiscriminate to highly selective. Extensive research has evaluated the impacts of selective hunting on animal populations. In contrast, the ways in which indiscriminate hunting pressure can shape populations of non-target species has not yet received comparable attention. We used empirical field data collection and simulation modelling to predict the persistence of an African lion population (Panthera leo) subject to indiscriminate hunting pressure from non-target subsistence poaching via wire snares in Murchison Falls National Park, Uganda. Our simulation modelling predicted lion population extirpation following a 50 % rise of lethal poaching pressure above the observed levels. When lethal poaching pressure doubled, the lion population was extirpated in ~70 % of our simulations. We then simulated reductions in lethal poaching pressure to quantify the predicted population recovery of lions. We found that the lion population increased by 40 % with reductions in lethal poaching pressure of 50 %. When we removed lethal poaching pressure entirely, the lion population nearly doubled in just 18 years. Our results demonstrate that by reducing the density of wire snares in the study area by just 2.79/km2, the lion population transitioned from being locally extirpated in 67 % of the simulations to reaching carrying capacity inside of two lion generations. We explore how vulnerable even non-target animals are to subsistence poaching and describe the types of applied practices that can be implemented to reduce wire snaring and effectively promote the population recovery of species of conservation concern

Evaluation of Revalor-XH for beef heifers fed different days on feed

Heifers were treated with either no implant, an initial implant of Revalor-200 and re-implanted with Revalor-200, or Revalor-XH and assigned to one of four serial slaughter harvests at 151, 165, 179, and 193 days on feed to determine the effects on feedlot performance and carcass characteristics. Implanting heifers increased final BW, ADG and HCW while decreasing marbling score and improving feed efficiency compared to non-implanted heifers. Increasing days on feed decreased ADG while increasing feed efficiency, HCW, fat thickness, marbling score, and calculated yield grade. By increasing HCW sold, implanting revenue can be maximized, assuming added risk for YG discounts

An Extension to the Frenet-Serret and Bishop Invariant Extended Kalman Filters for Tracking Accelerating Targets

This paper presents an extension to the original Frenet-Serret and Bishop frame target models used in the invariant extended Kalman filter (IEKF) to account for tangential accelerations for highly-manoeuvrable targets. State error propagation matrices are derived for both IEKFs and used to build the accelerating Frenet-Serret (FSa-LIEKF) and Bishop (Ba-LIEKF) algorithms. The filters are compared to the original Frenet-Serret and Bishop algorithms in a tracking scenario featuring a target performing a series of complex manoeuvres. The accelerating forms of the LIEKF are shown to improve velocity estimation during non-constant velocity trajectory segments at the expense of increased noise during simpler manoeuvres

Site and Extent of Digestion of Finishing Diets Containing Syngenta Enhanced Feed Corn

Four ruminally and duodenally fistulated steers were utilized to evaluate the effects of Syngenta Enhanced Feed Corn™ containing an alpha amylase enzyme trait (SYT- EFC) compared to the isoline parental control corn without the alpha amylase enzyme trait (Negative Isoline) on site and extent of digestion in finishing diets. Cattle fed SYT- EFC dry rolled corn had numerically greater postruminal starch digestibility, excreted lower fecal starch, and had greater total tract starch digestibility compared to cattle fed Negative Isoline corn. These data would suggest that cattle are able to utilize more starch from corn containing the SYT- EFC trait, which has resulted in greater gains and efficiencies

Panel options for large precision radio telescopes

The Cornell Caltech Atacama Telescope (CCAT) is a 25 m diameter telescope that will operate at wavelengths as short as 200 microns. CCAT will have active surface control to correct for gravitational and thermal distortions in the reflector support structure. The accuracy and stability of the reflector panels are critical to meeting the 10 micron HWFE (half wave front error) for the whole system. A system analysis based upon a versatile generic panel design has been developed and applied to numerous possible panel configurations. The error analysis includes the manufacturing errors plus the distortions from gravity, wind and thermal environment. The system performance as a function of panel size and construction material is presented. A compound panel approach is also described in which the reflecting surface is provided by tiles mounted on thermally stable and stiff sub-frames. This approach separates the function of providing an accurate reflecting surface from the requirement for a stable structure that is attached to the reflector support structure on three computer controlled actuators. The analysis indicates that there are several compound panel configurations that will easily meet the stringent CCAT requirements

Toward Reproducible Baselines: The Open-Source IR Reproducibility Challenge

The Open-Source IR Reproducibility Challenge brought together developers of open-source search engines to provide reproducible baselines of their systems in a common environment on Amazon EC2. The product is a repository that contains all code necessary to generate competitive ad hoc retrieval baselines, such that with a single script, anyone with a copy of the collection can reproduce the submitted runs. Our vision is that these results would serve as widely accessible points of comparison in future IR research. This project represents an ongoing effort, but we describe the first phase of the challenge that was organized as part of a workshop at SIGIR 2015. We have succeeded modestly so far, achieving our main goals on the Gov2 collection with seven opensource search engines. In this paper, we describe our methodology, share experimental results, and discuss lessons learned as well as next steps

Evaluation of Distillers Grains Components Singly or in Combination in a Calf Fed Feedlot Study

A finishing study was conducted to determine the value of the fiber, protein, fat, and solubles components from wet distillers grains plus solubles (WDGS) alone or in combination for feedlot cattle in comparison to WDGS diets. The fiber portion alone did not improve F:G. When protein was included in the composite with fiber, F:G improved. With fat and solubles both added separately, F:G continued to improve. None of the components alone could make up the feeding value of WDGS, however the composite diet of fiber, protein, fat, and solubles combined matched the performance observed when WDGS is fed