The Gamma-ray Albedo of the Moon

We use the GEANT4 Monte Carlo framework to calculate the gamma-ray albedo of the Moon due to interactions of cosmic ray (CR) nuclei with moon rock. Our calculation of the albedo spectrum agrees with the EGRET data. We show that the spectrum of gamma rays from the Moon is very steep with an effective cutoff around 3-4 GeV (600 MeV for the inner part of the Moon disk) and exhibits a narrow pion-decay line at 67.5 MeV, perhaps unique in astrophysics. Apart from other astrophysical sources, the albedo spectrum of the Moon is well understood, including its absolute normalisation; this makes it a useful "standard candle" for gamma-ray telescopes. The steep albedo spectrum also provides a unique opportunity for energy calibration of gamma-ray telescopes, such as the forthcoming Gamma Ray Large Area Space Telescope (GLAST). Since the albedo flux depends on the incident CR spectrum which changes over the solar cycle, it is possible to monitor the CR spectrum using the albedo gamma-ray flux. Simultaneous measurements of CR proton and helium spectra by the Payload for Antimatter-Matter Exploration and Light-nuclei Astrophysics (PAMELA), and observations of the albedo gamma rays by the GLAST Large Area Telescope (LAT), can be used to test the model predictions and will enable the LAT to monitor the CR spectrum near the Earth beyond the lifetime of the PAMELA.Comment: 6 pages, 4 figures, emulateapj.cls; to appear in the Astrophysical Journa

Two Trees: Asset Price Dynamics Induced by Market Clearing

If stocks go up, investors may want to rebalance their portfolios. But investors cannot all rebalance. Expected returns may need to change so that the average investor is still happy to hold the market portfolio despite its changed composition. In this way, simple market clearing can give rise to complex asset market dynamics. We study this phenomenon in a very simple model. Our model has two Lucas trees.' Each tree has i.i.d.dividend growth, and the representative investor has log utility. We are able to give analytical solutions to the model. Despite this simple setup, price-dividend ratios, expected returns, and return variances vary through time. A dividend shock leads to underreaction' in some states, as expected returns rise and prices slowly adjust, and overreaction' in others. Expected returns and excess returns are predictable by price-dividend ratios in the time series and in the cross section, roughly matching value effects and return forecasting regressions. Returns generally display positive serial correlation and negative cross-serial correlation, leading to 'momentuem,' but the opposite signs are possible as well. A shock to one asset's dividend a.ects the price and expected return of the other asset, leading to substantial correlation of returns even when there is no correlation of cash flows and giving the appearance of contagion.' Market clearing allows the inverse portfolio' problem to be solved, in which the weights of the assets in the market portfolio are inverted' to solve for the parameters of the assets' return generating process.

Experimental Validation of Ex-Vessel Neutron Spectrum by Means of Dosimeter Materials Activation Method

Neutron spectrum information in reactor core and around of ex-vessel reactor needs to be known with a certain degree of accuracy to support the development of fuels, materials, and other components. The most common method to determine neutron spectra is by utilizing the radioactivation of dosimeter materials. This report presents the evaluation of neutron flux incident on M3dosimeter sets which were irradiated outside the reactor vessel,as well as the validation of neutron spectrum calculation. Al capsules containing both dosimeter set covered withCd and dosimeter set without Cd cover have been irradiated during the 35th operational cycle in the M3 ex-vessel irradiation hole position207 cmfrom core centerline at the space between the reactor vessel and the safety vessel. The capsules were positioned at Z=0.0 cm of core midplane. Each dosimeter set consists of Co-Al, Sc, Fe, Np, Nb, Ni, B, and Ta. The gamma-ray spectra of irradiated dosimeter materials were measured by 63 cc HPGe solid-state detector and photo-peak spectra were analyzed using BOB75 code. The reaction rates of each dosimeter materials and its uncertainty were analyzed based on 59Co (n,g) 60Co, 237Np (n,f) 95Zr-103Ru, 45Sc (n,g) 46Sc, 58Fe (n,g) 59Fe, 181Ta (n,g) 182Ta, and 58Ni (n,p)58Co reactions. The measured Cd ratios indicate that neutron spectrum at the irradiated dosimeter sets was dominated by low energy neutron. The experimental result shows that the calculated neutron spectra by DORT code at the ex-vessel positions need correction, especially in the fast neutron energy region, so as to obtain reasonable unfolding result consistent with the reaction rate measurement without any exception. Using biased DORT initial spectrum, the neutron spectrum and its integral quantity were unfolded by NEUPAC code. The result shows that total neutron flux, flux above 1.0 MeV, flux above 0.1 MeV, and the displacement rate of the dosimeter set not covered with Cd were 1.75× 1012 n cm2 s-1, 1.83× 108 n cm2 s-1, 2.94× 1010 n cm2 s-1, and 2.39× 10-11 dpa s-1, respectively. The uncertainty of neutron flux by NEUPAC was mainly due to the error of the initial spectrum.Received: 10 December 2015; Revised: 14 July 2016; Accepted: 25 September 201

Postcranial remains of Fabrosauridae (Reptilia: Ornithischia) from the Stormberg of southern Africa

The postcranial skeletons of three fabrosaurids from the upper Elliot Formation "Red Beds" of the Stormberg Group in southern Africa are described. The material demonstrates details of fabrosaurid anatomy previously unknown, particularly a short, deep prepubic process which is undoubtedly primitive for the Ornithischia. Besides the short prepubis, fabrosaurids are characterized by 1) a reduced manus; 2) an ilium having a lateral extension of the supra-acetabular margin and a deep nearly vertical brevis shelf; and 3) an elongated hindlimb. Postcranial morphology excludes the fabrosaurids from the ancestry of the contemporaneous heterodontosaurids. Neither can the fabrosaurids be considered ancestral to the 'juvenile scelidosaurid' (BMNH R6704) as has been suggested. On the contrary, the 'scelidosaurid' is more primitive in structure than fabrosaurids. The assignment of Nanosaurus agilis Marsh to the Fabrosauridae is not substantiated after morphological comparisons between the postcranial material of both. The taxonomic status of Scutellosaurus lawleri is regarded as uncertain. The fabrosaurids are more similar to the Morrison Formation camptosaurids, than to Hypsilophodon. Finally, it is argued that ornithopods were not a basal stock for the phylogenesis of non-ornithopods but represent an independent radiation comparable to the other ornithischian suborders. The fabrosaurids were an early development of the ornithopod radiation itself

New records of moths (Insecta, Lepidoptera) from urban gardens on Terceira Island with new data on recently introduced species to the Azores

The urban Duque da Terceira Garden, in the main town of Angra do Heroísmo (Terceira, Azores), was investigated to describe the species composition of moths (Insecta, Lepidoptera). Moths were sampled with two methods: SLAM traps (between April and September 2017) and light trapping (two sessions in the summer of 2017). A total of 42 taxa were sampled with the addition of 19 new records for Duque da Terceira Garden, five of which were also new records for Terceira Island. The five species recorded as new for Terceira were subjected to an exhaustive taxonomic analysis. In addition, we revised the colonization status of some species. Our results show that urban gardens may help the establishment of exotic species and that it is necessary to monitor and control how these species established in urban environments.info:eu-repo/semantics/publishedVersio

Treatment of Massive Metagenomic Data with Graphs

Among the de novo strategies to assemble metagenomic DNA fragments the application of de Bruijn graphs stands out. These graphs greatly reduce the computational complexity and overload that arises as a consequence of the huge data volume. An Eulerian cycle can be established on a de Bruijn graph that allows the assembly of sequence reads into longer fragments for genome reconstruction. This paper shows the theoretical principles of the computational schema applied. Also, the difficulties that appear in the practical application of the method and the algorithmic features of some of the available open source programs. Finally, the work of the authors research group is summarized.Facultad de Informátic

Treatment of Massive Metagenomic Data with Graphs

Among the de novo strategies to assemble metagenomic DNA fragments the application of de Bruijn graphs stands out. These graphs greatly reduce the computational complexity and overload that arises as a consequence of the huge data volume. An Eulerian cycle can be established on a de Bruijn graph that allows the assembly of sequence reads into longer fragments for genome reconstruction. This paper shows the theoretical principles of the computational schema applied. Also, the difficulties that appear in the practical application of the method and the algorithmic features of some of the available open source programs. Finally, the work of the authors research group is summarized.Facultad de Informátic

Designing Smart Applications Using AR (Augmented Reality)

Augmented Reality is rapidly developing in popularity because it brings elements of the virtual world, into our real world. Augmented Reality (AR) is a variation of Virtual Reality (VR). VR technologies immerses a user inside an imaginary environment. While immersed, the user cannot see the real world around them. In contrast, AR allows the user to see the real world, with virtual objects and information intertwined. Therefore, AR supplements reality and enhances the things we see, hear, and feel. This research project will implement a Web page that gives the user the opportunity to experiment with AR