Fermion Masses and Coupling Unification in E6. Life in the Desert

We present an $E_6$ Grand Unified model with a realistic pattern of fermion masses. All standard model fermions are unified in three fundamental 27-plets (i.e. supersymmetry is not invoked), which involve in addition right handed neutrinos and three families of vector like heavy quarks and leptons. The lightest of those can lie in the low TeV range, being accessible to future collider experiments. Due to the high symmetry, the masses and mixings of all fermions are closely related. The new heavy fermions play a crucial role for the quark and lepton mass matrices and the bilarge neutrino oscillations. In all channels generation mixing and ${\cal CP}$ violation arise from a single antisymmetric matrix. The $E_6$ breaking proceeds via an intermediate energy region with SU(3)_L\tm SU(3)_R\tm SU(3)_C gauge symmetry and a discrete left-right symmetry. This breaking pattern leads in a straightforward way to the unification of the three gauge coupling constants at high scales, providing for a long proton lifetime. The model also provides for the unification of the top, bottom and tau Yukawa couplings and for new interesting relations in flavor and generation space.Comment: RevTex4, three ps figures, some correction

THE MODEL CHARACTERISTICS OF JUMP ACTIONS STRUCTURE OF HIGH PERFORMANCE FEMALE VOLLEYBALL PLAYERS

The purpose of this study was to develop generalized and individual models of the jump actions of skilled female volleyball players. The main prerequisite for the development of the jump actions models were the results of our earlier studies of factor structure of jump actions of 10 sportswomen of the Polish volleyball team "Gedania" (Premier League) in the preparatory and competitive periods of the annual cycle of preparation. The athletes age was 22.0 +- 2.9 years, the sports experience - 8.1 +- 3.1 years, body height - 181.9 +- 8.4 years and body weight - 72.8 +- 10.8 kg. Mathematical and statistical processing of the data (the definition of M ± SD and significant differences between the samples) was performed using a standard computer program "STATISTICA 7,0". Based on the analysis of the factor structure of 20 jump actions of skilled women volleyball players determined to within 5 of the most informative indexes and their tentative values recommended for the formation of a generalized model of this structure. Comparison of individual models of jump actions of skilled women volleyball players with their generalized models in different periods of preparation can be used for the rational choice of means and methods for the increasing of the training process efficiency

A Predictive Minimal Model for Neutrino Masses and Mixings

A model is considered in which the scale of the heavy singlet neutrinos is a few orders of magnitude below the grand unification scale and where right-handed vector bosons play still a negligible role. In a basis with diagonal up-quark and Dirac-neutrino mass matrices it is assumed that the heavy neutrino mass matrix has only zero elements in its diagonal, in analogy to the light neutrino mass matrix in the Zee model. Connecting then the remaining matrix elements with the small parameter describing the hierarchy of quark masses and mixings and by assuming commutativity of the charged lepton with the down-quark mass matrix, the calculation of all neutrino properties can be performed in terms of the two mass differences relevant for atmospheric and solar neutrino oscillations. CP-violation is directly related to CP-violation in the quark sector.Comment: revtex, 9 pages, two references added, to be published in Phys. Rev. D presented at Neutrino' 2000, Sudbury, Canad

Form factor relations for heavy-to-heavy and heavy-to-light meson transitions

Relations between the form factors that parametrize the hadronic matrix elements, in spectator decays of heavy mesons, have been derived by Stech within the constituent quark model. In here, we examine these relations using a slightly modified description of the meson states. We find new and very general relations for some of the form factors. For the other form factors, we obtain small modifications to the relations previously derived by Stech, in the case of heavy-to-light transitions.Comment: 13 pages, LaTex, 2 figure

Molecular data suggest long-term in Situ Antarctic persistence within Antarctica's most speciose plant genus, Schistidium

© 2018 Biersma, Jackson, Stech, Griffiths, Linse and Convey. From glacial reconstructions it is clear that Antarctic terrestrial life must have been extremely limited throughout Quaternary glacial periods. In contrast, recent biological studies provide clear evidence for long-term in situ persistence throughout glacial times within most extant Antarctic faunal and several microbial groups. However, even now, the evolutionary history of the Antarctic flora-despite playing major role in Antarctic ecosystems-remains poorly studied. We assessed the diversity, richness and relative age divergences within Schistidium (Grimmiaceae, Bryophyta), the most species-rich plant genus in the Antarctic, as well as the plant genus containing most Antarctic endemic species. We applied phylogenetic and molecular dating methods based on nuclear ribosomal Internal Transcribed Spacer sequences, including all known Antarctic Schistidium species with available sample material. We additionally investigated the continent-wide genetic diversity within the most common Antarctic representative of the genus-the endemic species Schistidium antarctici-and performed preliminary phylogeographic analyses of the bipolar species Schistidium rivulare. Most previously described Antarctic Schistidium species were genetically distinct, confirming their specific status. Interspecific divergences of all species took place at least ~1 Mya, suggesting a likely in situ persistence in Antarctica for (at least) all endemic Schistidium species. The widespread endemic species, Schistidium antarctici, diverged from other Antarctic congeners in the late Miocene, thereby revealing the oldest extant plant species currently known in Antarctica, and providing increasing support for the hypothesis of vegetation survival through multiple glacial periods. Within S. antarctici we identified several distinct clades dividing the eastern Antarctic Peninsula and Scotia Arc islands from the western Antarctic Peninsula and all continental locations. This suggests that the mountainous spine on the Antarctic Peninsula forms a strong barrier to gene flow in this species, while increased genetic diversity in the northern Maritime Antarctic indicates likely glacial refugia in this area. This study provides an important first step toward assessing the diversity and evolutionary history of the most speciose moss genus in the Antarctic. The multi-million year presence of several endemic species contributes to studies on their adaptive potential to survive climate change over both historical and contemporary timescales.NERC STUDENTSHIP NE/K50094X/

Ptychostomum touwii, a new bryophyte species distinguished from Ptychostomum rubens by iterative morpho-molecular analysis, and a note on Bryum microerythrocarpum

DNA barcoding of Dutch collections of Ptychostomum rubens (Mitt.) Holyoak & N.Pedersen as understood in modern Floras revealed two distinct taxa. A morphological study of these specimens recognized several characters which can be used for identification. Ptychostomum rubens as well as its synonym Bryum bomanssonii Lindb. are lectotypified here. These lectotypes, and hence these two taxa, belong to the same morpho-molecular species. The other species is described here as a new species: Ptychostomum touwii Bijlsma, Kruijer & M.Stech. A key to these two species and the closely related P. bornholmense (Wink. & R.Ruthe) Holyoak & N.Pedersen is given. Their distribution and ecology in the Netherlands are briefly discussed. Ptychostomum rubens is a widespread species in the Netherlands, occurring on disturbed, base-rich, often calcareous and nutrient-rich soils, whereas P. touwii is calcifuge and prefers disturbed, less nutrient-rich, sandy soils and loams. The distribution range of the latter species needs to be clarified yet. After studying material from the South American species Bryum subapiculatum Hampe, B. dentiferum Hampe, and B. rubrinerve Cardot & Broth., we propose to exclude these species from the species concept of B. microerythrocarpum Müll.Hal. & Kindb. awaiting further molecular research of this variable species complex. Since, based on previous molecular research, B. subapiculatum is recently classified in the genus Imbribryum N. Pedersen and B. subapiculatum and B. microerythrocarpum are closely related, we also make the new combination Imbribryum microerythrocarpum (Müll.Hal. & Kindb.) Bijlsma, Kruijer & M. Stech.Plant sciencesNaturali

Non-local anomaly of the axial-vector current for bound states

We demonstrate that the amplitude $<\rho\gamma|\partial_\nu (\bar q\gamma_\nu \gamma_5 q)|0>$ does not vanish in the limit of zero quark masses. This represents a new kind of violation of the classical equation of motion for the axial current and should be interpreted as the axial anomaly for bound states. The anomaly emerges in spite of the fact that the one loop integrals are ultraviolet-finite as guaranteed by the presence of the bound-state wave function. As a result, the amplitude behaves like $\sim 1/p^2$ in the limit of a large momentum $p$ of the current. This is to be compared with the amplitude $$ which remains finite in the limit $p^2\to\infty$. The observed effect leads to the modification of the classical equation of motion of the axial-vector current in terms of the non-local operator and can be formulated as a non-local axial anomaly for bound states.Comment: revtex, 4 pages, numerical value for $\kappa$ in Eq. (19) is corrected, Eqs. (22) and (23) are modified. New references added. Results remain unchange

Leading twist moments of the neutron structure function F2n

We perform a global analysis of neutron F2n structure function data, obtained by combining proton and deuteron measurements over a large range of kinematics. From these data the lowest moments (n <= 10) of the leading twist neutron F2n structure function are extracted. Particular attention is paid to nuclear effects in the deuteron, which become increasingly important for the higher moments. Our results for the nonsinglet, isovector (p - n) combination of the leading twist moments are used to test recent lattice simulations. We also determine the lowest few moments of the higher twist contributions, and find these to be approximately isospin independent, suggesting the possible dominance of ud correlations over uu and dd in the nucleon.Comment: 34 pages, 13 figures. Minor changes. Version to appear in NP

Remote sensing: Physical principles, sensors and products, and the LANDSAT

Techniques of data acquisition by remote sensing are introduced in this teaching aid. The properties of the elements involved (radiant energy, topograph, atmospheric attenuation, surfaces, and sensors) are covered. Radiometers, photography, scanners, and radar are described as well as their products. Aspects of the LANDSAT system examined include the characteristics of the satellite and its orbit, the multispectral band scanner, and the return beam vidicon. Pixels (picture elements), pattern registration, and the characteristics, reception, and processing of LANDSAT imagery are also considered