On univoque Pisot numbers

We study Pisot numbers $\beta \in (1, 2)$ which are univoque, i.e., such that there exists only one representation of 1 as $1 = \sum_{n \geq 1} s_n\beta^{-n}$, with $s_n \in \{0, 1\}$. We prove in particular that there exists a smallest univoque Pisot number, which has degree 14. Furthermore we give the smallest limit point of the set of univoque Pisot numbers.Comment: Accepted by Mathematics of COmputatio

Application of general formulas for the correction of a lattice-translocation defect in crystals of a lentiviral integrase in complex with LEDGF.

The symmetry inherent to many biological macromolecular assemblies has been implicated in a range of crystal pathologies, including lattice-translocation defects (LTDs). Crystals suffering from classic LTDs contain two lattices that are shifted with respect to each other but nonetheless remain within the length of coherent interference. LTD introduces an undesirable intensity modulation into diffraction data, resulting in scrambled or partially scrambled electron densities. In this report, LTD theory is extended and a new general method for determining defect fractions is developed based on the heights of the non-origin peaks observed in native Patterson maps. The application of this method to crystals of lentiviral integrase in complex with its cofactor, where the observed translocation vector does not equal a small integral fraction of a unit-cell edge, is reported and its general application to all classic LTD cases is predicted

Identification of Ancient Feather Fragments Found in Melting Alpine Ice Patches in Southern Yukon

Twelve ancient artifacts or fragmented feather samples recovered from melting alpine ice patches in southern Yukon were analyzed in order to identify the species of birds associated with the ice patches or used on weapons recovered from these sites. The identification of bird species used by ancient hunters as long ago as 4500 BP enhances our insight into the customs, culture, and sophistication of life at that time. Downy feather barbs were found on two samples and microscopically identified as duck (Anatidae) and falcon (Falconidae). Further examination and comparisons using museum specimens resulted in a total of six identifications: Anatidae, eagle (Aquila or Haliaeetus), gyrfalcon (Falco rusticolus), white-tailed ptarmigan (Lagopus leucurus), short-eared owl (Asio flammeus), and northern flicker (Colaptes auratus luteus). Three of the feather samples were complete enough to show apparent modification, or notching, along the feather shaft. The identification of non-game birds such as gyrfalcon and eagles, together with evidence of possible worked or notched feathers, indicates that as long as 4500 years ago, Subarctic hunters selected feathers not only for their utility in fletching, but also possibly for symbolic or decorative purposes.On a analysé 12 anciens artefacts ou échantillons de fragments de plumes découverts dans le sud du Yukon lors de la fonte de plaques de glace alpine, afin d’identifier les espèces aviaires associées à ces plaques de glace ou utilisées sur les armes provenant de ces sites. L’identification des espèces aviaires utilisées par les anciens chasseurs à une époque aussi reculée que 4500 BP nous permet de mieux comprendre les coutumes, la culture et le degré de sophistication de la vie à cette époque. On a trouvé des barbes duveteuses sur deux échantillons et l’analyse au microscope a révélé qu’elles appartenaient à un canard (anatidé) et à un faucon (falconidé). Un examen plus poussé et des comparaisons avec des spécimens présents dans des musées ont permis d’établir six provenances: anatidé, aigle (Aquila ou Haliaeetus), faucon gerfaut (Falco rusticolus), lagopède à queue blanche (Lagopus leucurus), hibou des marais (Asio flammeus) et pic flamboyant (Colaptes auratus luteus). Trois des échantillons de plumes étaient assez complets pour révéler des modifications apparentes ou encoches, le long de la tige de la plume. L’identification d’oiseaux non cynégétiques tels que le faucon gerfaut et les aigles, combinée avec la découverte de plumes encochées ou éventuellement travaillées, révèle qu’il y a 4500 ans, les chasseurs subarctiques sélectionnaient déjà les plumes non seulement dans un but utilitaire pour en faire des empennes de flèches, mais peut-être aussi à des fins symboliques ou d’ornementation

Subobject Detection through Spatial Relationships on Mobile Phones

We present a novel image classification technique for detecting multiple objects (called subobjects) in a single image. In addition to image classifiers, we apply spatial relationships among the subobjects to verify and to predict locations of detected and undetected subobjects, respectively. By continuously refining the spatial relationships throughout the detection process, even locations of completely occluded exhibits can be determined. Finally, all detected subobjects are labeled and the user can select the object of interest for retrieving corresponding multimedia information. This approach is applied in the context of PhoneGuide, an adaptive museum guidance system for camera-equipped mobile phones. We show that the recognition of subobjects using spatial relationships is up to 68% faster than related approaches without spatial relationships. Results of a field experiment in a local museum illustrate that unexperienced users reach an average recognition rate for subobjects of 85.6% under realistic conditions

Simvastatin impairs the induction of pulmonary fibrosis caused by a western style diet: A preliminary study

The role of an atherogenic diet in causing pulmonary fibrosis has received little attention and simvastatin has been shown to reduce pulmonary fibrosis in animal models. To determine if an atherogenic diet can induce pulmonary fibrosis and whether simvastatin treatment is beneficial by up-regulating heat shock protein 70 and 90. New Zealand white rabbits (n = 15) were divided: Group 1 (control); Group 2 (MC) received a normal rabbit diet with 1% methionine plus 0.5% cholesterol (atherogenic diet). Group 3 received the same diet as the MC group plus 5 mg/kg/day simvastatin orally (MCS). After 4 weeks, the lungs were collected and analysed. Picrosirus red staining of lung interstitial collagen content showed that the atherogenic diet increased fibrosis 2.9-fold (P < 0.05), bronchiole adventitial collagen was increased 2.3-fold (P < 0.05) and bronchiole epithelium was increased 34-fold (P < 0.05), and simvastatin treatment severely reduced this effect (P < 0.05). Western blot analysis showed that the atherogenic diet significantly reduced lung Hsp70 protein by 22% (P < 0.05) and Hsp90 protein by 18% (P < 0.05) and simvastatin treatment did not affect this result. However, aortic hyper-responsiveness to vasoconstrictors (angiotensin II and phenylephrine) were markedly reduced by simvastatin treatment. We report that an atherogenic diet stimulates pulmonary fibrosis and reduces lung Hsp70/Hsp90 protein concentration. Simvastatin impairs this by mechanisms unrelated to Hsp70/Hsp90, but possibly a reduction in angiotensin II receptor or alpha adrenergic receptor pathways. These results could have implications in idiopathic pulmonary fibrosis

Cosmic Ray Physics with the LOFAR Radio Telescope

The LOFAR radio telescope is able to measure the radio emission from cosmic ray induced air showers with hundreds of individual antennas. This allows for precision testing of the emission mechanisms for the radio signal as well as determination of the depth of shower maximum $X_{\max}$, the shower observable most sensitive to the mass of the primary cosmic ray, to better than 20 g/cm$^2$. With a densely instrumented circular area of roughly 320 m$^2$, LOFAR is targeting for cosmic ray astrophysics in the energy range $10^{16}$ - $10^{18}$ eV. In this contribution we give an overview of the status, recent results, and future plans of cosmic ray detection with the LOFAR radio telescope.Comment: Proceedings of the 26th Extended European Cosmic Ray Symposium (ECRS), Barnaul/Belokurikha, 201

Open-domain topic identification of out-of-domain utterances using Wikipedia

Users of spoken dialogue systems (SDS) expect high quality interactions across a wide range of diverse topics. However, the implementation of SDS capable of responding to every conceivable user utterance in an informative way is a challenging problem. Multi-domain SDS must necessarily identify and deal with out-of-domain (OOD) utterances to generate appropriate responses as users do not always know in advance what domains the SDS can handle. To address this problem, we extend the current state-of-the-art in multi-domain SDS by estimating the topic of OOD utterances using external knowledge representation from Wikipedia. Experimental results on real human-to-human dialogues showed that our approach does not degrade domain prediction performance when compared to the base model. But more significantly, our joint training achieves more accurate predictions of the nearest Wikipedia article by up to about 30% when compared to the benchmarks

In defence of global egalitarianism

This essay argues that David Miller's criticisms of global egalitarianism do not undermine the view where it is stated in one of its stronger, luck egalitarian forms. The claim that global egalitarianism cannot specify a metric of justice which is broad enough to exclude spurious claims for redistribution, but precise enough to appropriately value different kinds of advantage, implicitly assumes that cultural understandings are the only legitimate way of identifying what counts as advantage. But that is an assumption always or almost always rejected by global egalitarianism. The claim that global egalitarianism demands either too little redistribution, leaving the unborn and dissenters burdened with their societies' imprudent choices, or too much redistribution, creating perverse incentives by punishing prudent decisions, only presents a problem for global luck egalitarianism on the assumption that nations can legitimately inherit assets from earlier generations – again, an assumption very much at odds with global egalitarian assumptions