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Conodonts are a clade of chordates and are valuable indicator fossils for biostratigraphy. The segminiplanate (neogondolelliform) conodonts represent a major morphological group ranging from upper Carboniferous to Upper Triassic marine sediments. However, the morphological similarity of segminiplanate P 1 elements generates problems for taxonomy, especially in the Permian and Triassic clades. Thi

The end-Permian mass extinction, ∼252 million years ago, is notable for a complex recovery period of ∼5 Myr. Widespread euxinic (anoxic and sulfidic) oceanic conditions have been proposed as both extinction mechanism and explanation for the protracted recovery period, yet the vertical distribution of anoxia in the water column and its temporal dynamics through this time period are poorly constrain

Radionuclide therapy is the use of radioactive drugs for internal radiotherapy, mainly for the treatment of metastatic disease. As opposed to systemic cancer therapies in general, the use of radioactively labeled drugs results not only in a targeted therapy but also the possibility of imaging the distribution of the drug during therapy. From such images, the absorbed doses delivered to tumors and

We present new data on the structure and age of the upper Permian strata in the basin of the Setorym River (tributary of the Vostochnaya Khandyga River) in the South Verkhoyansk region, represented by the Imtachan Formation and the lower part of the Nekuchan Formation. Based on the new findings of bivalve fossils from the Intomodesma costatum Zone, as well as on the study of carbon isotopes in the

Samples from strata spanning the Triassic-Jurassic boundary at the GSSP at Kuhjoch and at Kendlbachgraben were studied by NAA, XRF and combustion analysis to determine Ir levels and associated geochemistry. The results are compared to previously determined carbon isotope stratigraphy at these sections. Ir concentrations in the limestones of the Kössen Formation at Kuhjoch are very low (<. 10 pg/g)

Elasmobranchs are reported for the first time from Lower Triassic deposits in Oman. The well-preserved remains consist of isolated teeth, dermal denticles and fin spines, recovered from conodont residues. The low-palaeolatitude sections consist of Lopingian-Olenekian shallow and pelagic carbonates in exotics, olistoliths and breccia blocks that have been redeposited in younger allochthonous strata

Jiarong (Huishui County, Guizhou Province, South China) is a key locality for the study of the Early Triassic recovery after the end-Permian mass extinction. The size reduction of conodonts at the Smithian/Spathian transition was first documented in Jiarong, and it is also a locality that contributes to the documentation of the Early Triassic paleo-seawater temperatures. In the Jiarong sections, t

We present a model with continuous or discrete abelian generation group G, which predicts all orders of magnitude for fermion masses ad mixings correctly as a function of only one small parameter φS M ≈ 1 10. Here φS is the scale of G symmetry breaking and M the fundamental mass scale of the theory. No small Yukawa couplings or special choices of the scalar potential are needed. We perform a syste

En sammantällning av de 40 orientaliska mynt som framkommit på anlöpsplatsen Vester Egesborg, Själland. Mynten analyseras med hänsyn till kronologi, ursprung och grad av fragmentering. Jämförelser görs med andra vikingatida handels- och centraplatser med orientaliska mynt som Kaupang, Uppåkra, Tissø, Birka och Strøby-Toftegård.

We examine patterns where ratios of the fermion masses and the W-boson mass (xi= mi mw) are proportional to powers of a small parameter λ(xi=ciλPi). For a simple estimate of the uncertainty in the coefficients ci we determine the allowed values of Pi and the corresponding range of λ. Using this information we search for realistic patterns in a large class of anomaly-free SU(3)×SU(2)×U(1)×U(1) mode

We calculate within chiral perturbation theory the cross section for γγ→π0π0 and γγ→π+π- to next-to-leading order. The first process only depends on the one-loop contributions and forms a test of chiral perturbation theory. We also calculate the pion electromagnetic form factor and compare it to recent data.

We present a discussion of the treatment of 1 Nc-corrections in chiral perturbation theory for nonleptonic weak processes. We compare the approach with an explicit cutoff and dimensional regularization in chiral perturbation theory and present evidence that they are equivalent. The quadratic dependence on the cutoff can be subtracted consistently at each level of 1 Nc. We discuss the identificatio

We study the value of the light quark masses combination mu + md in QCD using both Finite Energy Sum Rules and Laplace Sum Rules. We have performed a detailed analysis of both the perturbative QCD and the hadronic parametrization inputs needed in these Sum Rules. As main result, we obtain mu (1 GeV2 + md (1 GeV2) = (12 ± 2.5) MeV for the running MS masses.

The two-point functions in generalized Nambu-Jona-Lasinio models are calculated to all orders in momenta and quark masses to leading order in 1/Nc. The use of Ward identities and the heat-kernel expansion allows for a large degree of regularization independence. We also show how this approach works to the same order for three-point functions on the example of the vectorpseudoscalar-pseudoscalar th

The matrix elements for K → ππlν decays are described by four form factors F, G, H and R. We complete previous calculations by evaluating R at next-to-leading order in the low-energy expansion. We then estimate higher order contributions using dispersion relations and determine the low-energy constants L1, L2 and L3 from data on Ke4 decays and on elastic pion scattering. Finally, we present predic

We show how the effective action of the Extended Nambu-Jona-Lasinio model (ENJL) can be defined in the presence of anomalies in a way that reproduces the flavour anomaly. This necessarily breaks Vector Meson Dominance (VMD) in the usual sense. The same method can be used to construct other chiral effective theories involving constituent quarks and spin-1 mesons that give the correct flavour anomal

We discuss vector, axial-vector, scalar and pseudoscalar two-point functions at low and intermediate energies. We first review what is known from chiral perturbation theory, as well as from a heat kernel expansion within the context of an extended Nambu-Jona-Lasinio (ENJL) model. We derive then these two-point functions to all orders in the momenta and to leading order in 1/N c within the framewo

We evaluate the matrix elements for the radiative kaon decays K+ → l+νlγ, l+νll′+l′- and K → πlνlγ (l, l′ = e, μ) to next-to-leading order in chiral perturbation theory. We calculate total rates and rates with several kinematical cuts and confront the results with existing data. Measurements at future kaon facilities will allow for a more detailed comparison between theory and experiment.

We calculate the O(p6) corrections to the anomalous form factors appearing in π+, K+ → e+νγ, μ+νγ and K14 decays in chiral perturbation theory. The relevant dimension 6 terms of the lagrangian are evaluated assuming their saturation by the vector meson contribution.