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Photodisintegration is a main energy loss process for ultrahigh-energy cosmic-ray (UHECR) nuclei in intergalactic space. Therefore, it is crucial to understand systematic uncertainty in photodisintegration when simulating the propagation of UHECR nuclei. In this work, we calculated the cross sections using the random phase approximation (RPA) of density functional theory (DFT), a microscopic nuclear model. We calculated the E 1 strength of 29 nuclei using three different density functionals. We obtained the cross sections of photonuclear reactions, including photodisintegration, with the E 1 strength. Then, we implemented the cross sections in the cosmic-ray propagation code CRPropa. We found that assuming certain astrophysical parameter values, the difference between UHECR energy spectrum predictions using the RPA calculation and the default photodisintegration model in CRPropa can be more than the statistical uncertainty of the spectrum. We also found that the differences between the RPA calculations and CRPropa default in certain astrophysical parameters obtained by a combined fit of UHECR energy spectrum and composition data assuming a phenomenological model of UHECR sources can be more than the uncertainty of the data. [ABSTRACT FROM AUTHOR]

We compare two techniques for simulation of the propagation of ultra-high-energy cosmic rays (UHECR) in intergalactic space: the Monte Carlo approach and a method based on solving transport equations in one dimension. For the former, we adopt the publicly available tool CRPropa and for the latter, we use the code TransportCR, which has been developed by the first author and used in a number of applications, and is made available online with publishing this paper. While the CRPropa code is more universal, the transport equation solver has the advantage of a roughly 100 times higher calculation speed. We conclude that the methods give practically identical results for proton or neutron primaries if some accuracy improvements are introduced to the CRPropa code. [ABSTRACT FROM AUTHOR]

Sugarcane ( Saccharum spp.) is a clonally propagated outcrossing polyploid crop of great importance in tropical agriculture. Up to now, all sugarcane genetic maps had been developed using either full-sib progenies derived from interspecific crosses or from selfing, both approaches not directly adopted in conventional breeding. We have developed a single integrated genetic map using a population derived from a cross between two pre-commercial cultivars (‘SP80-180’ × ‘SP80-4966’) using a novel approach based on the simultaneous maximum-likelihood estimation of linkage and linkage phases method specially designed for outcrossing species. From a total of 1,118 single-dose markers (RFLP, SSR and AFLP) identified, 39% derived from a testcross configuration between the parents segregating in a 1:1 fashion, while 61% segregated 3:1, representing heterozygous markers in both parents with the same genotypes. The markers segregating 3:1 were used to establish linkage between the testcross markers. The final map comprised of 357 linked markers, including 57 RFLPs, 64 SSRs and 236 AFLPs that were assigned to 131 co-segregation groups, considering a LOD score of 5, and a recombination fraction of 37.5 cM with map distances estimated by Kosambi function. The co-segregation groups represented a total map length of 2,602.4 cM, with a marker density of 7.3 cM. When the same data were analyzed using JoinMap software, only 217 linked markers were assigned to 98 co-segregation groups, spanning 1,340 cM, with a marker density of 6.2 cM. The maximum-likelihood approach reduced the number of unlinked markers to 761 (68.0%), compared to 901 (80.5%) using JoinMap. All the co-segregation groups obtained using JoinMap were present in the map constructed based on the maximum-likelihood method. Differences on the marker order within the co-segregation groups were observed between the two maps. Based on RFLP and SSR markers, 42 of the 131 co-segregation groups were assembled into 12 putative homology groups. Overall, the simultaneous maximum-likelihood estimation of linkage and linkage phases was more efficient than the method used by JoinMap to generate an integrated genetic map of sugarcane. [ABSTRACT FROM AUTHOR]

Upper Devonian marine deposits of the Baruunhuurai Terrane in western Mongolia represent island arc settings, which yielded a diverse conodont assemblage of 30 taxa, including species of Ancyrognathus (as well as one new species), Icriodus , Mehlina , Polygnathus and Palmatolepis. Biodiversity analysis of Ancyrognathus , Pelekysgnathus , Mehlina and Icriodus shows that the Mongolian conodont assemblage consists of two endemic and few cosmopolitan taxa. Representatives of the otherwise globally distributed genus Pelekysgnathus are absent. An important factor influencing the regional distribution of conodont taxa seems to be the siliciclastic-dominated sedimentation of the Baruunhuurai Terrane during the early Famennian. • Biostratigraphic range at Hushoot Shiveetiin gol section (western Mongolia) covers Pa. min. minuta to Pa. rhomboidea biozones. • Among an assemblage of 30 conodont taxa, Ancyrognathus minjini n. sp. is newly described. • The early Famennian part of the section is dominated by polygnathid-palmatolepid conodont biofacies. [ABSTRACT FROM AUTHOR]

Photonuclear reactions of light nuclei below a mass of A = 60 are planned to be studied experimentally and theoretically with the PANDORA (Photo-Absorption of Nuclei and Decay Observation for Reactions in Astrophysics) project. Two experimental methods, virtual photon excitation by proton scattering and real photo absorption by a high-brilliance γ -ray beam produced by laser Compton scattering, will be applied to measure the photoabsorption cross sections and decay branching ratio of each decay channel as a function of the photon energy. Several nuclear models, e.g. anti-symmetrized molecular dynamics, mean-field and beyond-mean-field models, a large-scale shell model, and ab initio models, will be employed to predict the photonuclear reactions. The uncertainty in the model predictions will be evaluated based on the discrepancies between the model predictions and experimental data. The data and predictions will be implemented in the general reaction calculation code, TALYS. The results will be applied to the simulation of the photo-disintegration process of ultra-high-energy cosmic rays in inter-galactic propagation. [ABSTRACT FROM AUTHOR]

Abstract: The faunal characteristics, successions and geographical distribution of the Permian rugose corals in Inner Mongolia–Northeast China and Japan are reviewed using current coral taxonomy and the recently revised Permian global time scale. The co-occurrences of Cathaysian compound corals, abundant non-dissepimented solitary corals, and endemic corals indicate that Inner Mongolia and Northeast China represent an independent biogeographical entity, quite separate from South China and the Japanese terranes. However, the common occurrence in South China of Permian taxa such as Wentzellophyllum, Lonsdaleiastraea, Yatsengia, Ipciphyllum, and Waagenophyllum indicates, in a broad sense, a Tethyan affinity for the Akiyoshi and Mino terranes in Japan. Rocks from the Asselian to the Artinskian in the South Kitakami Terrane of Japan contain eleven large dissepimented solitary and compound genera, including Huangia, Iranophyllum, Laophyllum, Polythecalis, Sestrophyllum, Wentzelella, Wentzellophyllum and Yatsengia. These genera are all typical of, and common in, South China, but are absent from coeval strata in Northeast China. Middle Permian rocks in the South Kitakami Terrane also contain rugose corals that are abundant in South China, in some cases the same species, such as Parawentzelella regularis, Waagenophyllum indicum, Waagenophyllum virgalense and Yatsengia kiangsuensis. Thus, the coral faunas from the South Kitakami Terrane indicate a close paleobiogeographical affinity with those from South China, which is consistent with the paleobiogeography based on ammonoids and bivalves. [Copyright &y& Elsevier]

The aim of this study was to characterize the key physiological aspects of three sugarcane cultivars (RB92579, RB867515 and RB872552) under biological nitrogen fixation (BNF). Plants were generated in tubes containing aseptic substrates and these plants were transferred to pots containing washed sand, but watered with a mineral fertilizer, and inoculated with a mixture of five diazotrophic bacteria three times at seven-day intervals. Under BNF, all of the cultivars contained half of their total leaf nitrogen content and 50% less shoot dry mass. The leaves of plants under BNF showed approximately 65% less of the total protein content (TP). The gas-exchange control plants had twice the CO assimilation rates than the BNF plants. The activity of superoxide dismutase (SOD) and ascorbate peroxidase (APX) was increased in all cultivars under BNF when compared with the control; thus, the content of hydrogen peroxide (HO) was also increased in these plants. The results of this study indicate that after acclimatization, the inoculation of young plants from tissue culture with diazotrophic bacteria could supply approximately 50% of their nitrogen requirement. [ABSTRACT FROM AUTHOR]

Abstract: Since 2007, the Telescope Array (TA) experiment, based in Utah, USA, has been observing ultra high energy cosmic rays to understand their origins. The experiment includes a surface detector (SD) array and three fluorescence detector (FD) stations. The FD stations, installed surrounding the SD array, measure the air fluorescence light emitted from extensive air showers (EASs) for precise determination of their energies and species. The detectors employed at one of the three FD stations were relocated from the High Resolution Fly''s Eye (HiRes) experiment. At the other two stations, newly designed detectors were constructed for the TA experiment. An FD consists of a primary mirror and a camera equipped with photomultiplier tube pixels. To obtain the EAS parameters with high accuracy, understanding the FD optical characteristics is important. In this paper, we report the characteristics and installation of the new FDs and the performances of the FD components. The results of the monitored mirror reflectance during the observation time are also described in this report. [Copyright &y& Elsevier]