Hilbert-Schmidt Separability Probabilities and Noninformativity of Priors

The Horodecki family employed the Jaynes maximum-entropy principle, fitting the mean (b_{1}) of the Bell-CHSH observable (B). This model was extended by Rajagopal by incorporating the dispersion (\sigma_{1}^2) of the observable, and by Canosa and Rossignoli, by generalizing the observable (B_{\alpha}). We further extend the Horodecki one-parameter model in both these manners, obtaining a three-parameter (b_{1},\sigma_{1}^2,\alpha) two-qubit model, for which we find a highly interesting/intricate continuum (-\infty < \alpha < \infty) of Hilbert-Schmidt (HS) separability probabilities -- in which, the golden ratio is featured. Our model can be contrasted with the three-parameter (b_{q}, \sigma_{q}^2,q) one of Abe and Rajagopal, which employs a q(Tsallis)-parameter rather than $\alpha$, and has simply q-invariant HS separability probabilities of 1/2. Our results emerge in a study initially focused on embedding certain information metrics over the two-level quantum systems into a q-framework. We find evidence that Srednicki's recently-stated biasedness criterion for noninformative priors yields rankings of priors fully consistent with an information-theoretic test of Clarke, previously applied to quantum systems by Slater.Comment: 26 pages, 12 figure

Geometric morphometrics of macro- and meiofaunal priapulid pharyngeal teeth provides a proxy for studying Cambrian “tooth taxa”

Priapulids are marine, benthic ecdysozoan worms that feed using a distinctive toothed pharynx. While only a handful of lineages have survived to the present day, the Cambrian priapulid stem group left behind a rich record of articulated body fossils and characteristic trace fossils in the form of burrows. Recently, the fossil record of isolated priapulid cuticular elements including pharyngeal teeth has gained increased attention as a means of revealing cryptic priapulid taxa otherwise unknown among macrofossils. In this study, we focus on the ecological implications of shape variation in the teeth of extant and extinct priapulids, which display substantial morphological differences between taxa and life stages. We define a landmarking scheme to capture shape variation in priapulid teeth and apply it to our dataset, which includes a breadth of tooth specimens from extant macrofaunal and meiofaunal lineages alongside numerous Cambrian priapulid teeth preserved as isolated small carbonaceous fossils. Through ordination of the principal components of shape, we explore the priapulid tooth morphospace and find evidence that its occupancy has expanded since Cambrian times, indicating a corresponding expansion of the group’s ecological niche. We also employ our geometric morphometric approach to make linear discriminant analysis-based taxon assignments based on tooth morphology, which can be helpful for classifying enigmatic “tooth taxa” known solely from fossil teeth. Finally, we use discriminant analysis to study tooth shapes from a functional perspective, considering known ecologies to characterize the ecological functions of unclassified isolated teeth

Supporting failure? Damage inflicted to establishing trees in London by a range of tree support and protection systems

Urban foresters employ a diverse range of different tree support and protection systems (TSPS) to help trees establish in the urban environment; however, in some cases, TSPS can cause damage to their host trees. A survey was undertaken of 762 establishing trees across fourteen London boroughs to determine which types of TSPS are in current use, to assess how different systems perform and to record the frequency and severity of damage to trees associated with these different types and configurations of TSPS. We found that TSPS-associated damage was highly prevalent within the sampled population, affecting 34.8% of the trees surveyed. Failure to remove TSPS components after the establishment phase was responsible for more than 80% of the cases of severe damage to trees found by this survey. A comparison between the performance of several TSPS configurations in terms of their effectiveness and association with different TSPS damage types identified that the “two posts and ties” system performed consistently well in comparison with all other TSPS assessed. The survey data also highlighted a 35% rate of TSPSassociated damage related to the use of protective structures and that severe girdling damage and the development of adverse stem taper was more frequent when a TSPS incorporated the use of rubber spacers. We conclude that some simple changes to current tree planting practice would help to minimize the impact of TSPS-associated damage in our urban forests

A formal asymmetric synthesis of both enantiomers of the Erythrina Alkaloid 3-Demethoxyerythratidinone

A formal asymmetric synthesis of both enantiomers of the Erythrina alkaloid 3- demethoxyerythratidinone is reported through the application of a highly functionalised lactam template as an N-acyliminium precursor

An unexpected stereochemical course of dihydroimidazolium ylide cycloadditions

An unexpected stereochemical course of dihydroimidazolium ylide cycloaddition

Repeating adrenal vein sampling when neither aldosterone/cortisol ratio exceeds peripheral yields a high incidence of aldosterone-producing adenoma

Objectives:In primary aldosteronism, adrenal vein sampling (AVS) suggests unilateral aldosterone-producing adenoma (APA) when the aldosterone/cortisol (A/F) ratio is less than or equal to peripheral on one side and at least two times peripheral on the other. When A/F ratios are lower bilaterally than peripheral despite adequate samples (adrenal venous cortisol 3 times peripheral), we recommend repeat AVS. This study aimed to determine the frequency of this occurrence and outcomes in such cases.Methods:We performed a retrospective observational study of all cases of primary aldosteronism undergoing initial AVS over a 34-year period.Results:Initial AVS in 1397 patients returned satisfactory and discriminatory results in 1066 (76.3%) but 37 patients (2.6%) had adequate samples but bilateral A/F ratios no higher than peripheral. Of the 22 of these 37 who agreed to repeat AVS, 10 demonstrated unilateral aldosterone production, and eight of these had unilateral adrenalectomy disclosing APAs and resulting in cure (3) or improvement (5) in hypertension. Eight had bilateral aldosterone production. Four studies were inconclusive. Patients with initial unsatisfactory AVS because of bilaterally low A/F ratios had significantly (P=0.023) more unilateral disease [10 of 18 satisfactory repeat studies (55.6%) vs. 326 of 1066 satisfactory initial studies (30.6%)] and a significantly higher (67.6 vs. 49.9%, P=0.034) percentage of males.Conclusion:As the incidence of APAs was high in a subgroup with low A/F bilaterally on initial AVS, these patients should be offered repeat AVS. This might reflect both a greater dependence of aldosterone production on adrenocorticotrophic hormone (ACTH) in APAs and the pulsatile nature of ACTH secretion

Density-functional Study of Small Molecules within the Krieger-Li-Iafrate Approximation

We report density-functional studies of several small molecules ($H_{2}, N_{2}, CO, H_{2}O$, and $CH_{4}$) within the Krieger-Li-Iafrate (KLI) approximation to the exact Kohn-Sham local exchange potential, using a three-dimensional real-space finite-difference pseudopotential method. It is found that exchange-only KLI leads to markedly improved eigenvalue spectra compared to those obtained within the standard local-density approximation (LDA), the generalized gradient approximation (GGA), and the Hartree-Fock (HF) method. For structural properties, exchange-only KLI results are close to the corresponding HF values. We find that the addition of LDA or GGA correlation energy functionals to the KLI exact exchange energy functional does not lead to systematic improvements.Comment: 16 pages including 1 fugure, to be published in Phys. Rev. A Nov. 1 '9

The Design and Application of Target-Focused Compound Libraries

Target-focused compound libraries are collections of compounds which are designed to interact with an individual protein target or, frequently, a family of related targets (such as kinases, voltage-gated ion channels, serine/cysteine proteases). They are used for screening against therapeutic targets in order to find hit compounds that might be further developed into drugs. The design of such libraries generally utilizes structural information about the target or family of interest. In the absence of such structural information, a chemogenomic model that incorporates sequence and mutagenesis data to predict the properties of the binding site can be employed. A third option, usually pursued when no structural data are available, utilizes knowledge of the ligands of the target from which focused libraries can be developed via scaffold hopping. Consequently, the methods used for the design of target-focused libraries vary according to the quantity and quality of structural or ligand data that is available for each target family. This article describes examples of each of these design approaches and illustrates them with case studies, which highlight some of the issues and successes observed when screening target-focused libraries

A life less ordinary: analysis of the uniquely preserved tattooed dermal remains of an individual from 19th century France

‘Anthropologies of the Body’ often view the human form as a sort of text, onto which meanings and experiences are inscribed during people’s lives, rendering the body effectively as an artefact of material culture. Such ‘inscription’ is generally metaphorical; however, in the case of tattooing, aspects of the way people wish to be perceived are quite literally inscribed upon the body. The current article presents analysis of an unusual ‘artefact’ in the form of the major anterior portion of the preserved, tattooed skin of an adult male. The skin’s provenance was previously unknown, as was the reason why he had been subject to such treatment after death. The current project has progressed towards resolving these issues using multiple approaches, including CT scanning, multispectral light sources, infrared reflectography and spectroscopic dating. The latter technique produced a date range of 1861 ±15 years for the wood on which the skin was mounted. Multispectral and infrared light examination made it possible to discern many of the tattooed motifs much more clearly. The images and text that were made visible suggested this man had been French and had probably spent time overseas, possibly in naval service. Towards the end of his life, he may have been imprisoned and the date ‘1883’ was decipherable. The current analysis allowed the investigators to glean far more information than was initially expected, providing a considerably richer personal narrative of this individual through the content of his tattoos than is usually possible in biological anthropology