2,701 research outputs found
Alignment of Linear Biochemical Pathways Using Protein Structural Classification
Metabolic, signaling and regulatory pathways form the basis of biological processes and are important for the analysis of cellular behavior and evolution. This paper presents an approach of aligning biochemical pathways on the basis of the structure of involved proteins and their classification. The suitable information is retrieved from an integrated database system.
SIGNALIGN is available at: http://agbi.techfak.uni-bielefeld.de/signalign/index.jsp 


Description of two new actinosporean types from a brook of Fuji Mountain, Honshu, and from Chitose River, Hokkaido, Japan
Actinospore infection of oligochaetes living in the mud of 3 freshwater biotopes in Japan was studied. Using the cell-well plate method, a new aurantiactinomyxon type was found in 0.77 % of the examined Tubifex tubifex oligochaete specimens from a brook near Yamanashi Prefectural Fisheries Experimental Station on Fuji Mountain. In 0.14 % of Lumbriculus variagetus collected from Chitose River, near Chitose Salmon Hatchery, a new siedleckiella type was found, while at the same time 8.1 % of the Lumbriculus spp. oligochaetes released triactinomyxons of Myxobolus arcticus. Of the examined Rhyacodrilus komarovi oligochaetes collected from the Mena River system, Hokkaido, 0.2, 0.6, 0.5 and 0.8% were infected with echinactinomyxon, neoactinomyxum and 2 types of triactinomyxon spores, respectively, and described in our previous paper. The oligochaetes released actinospores for several weeks. Actinospore infection showed high intensity in positive oligochaetes in the case of all the actinosporean types. Two of the actinospore types (aurantiactinomyxon and siedleckiella) presented here have not been previously described
Magnetic susceptibilities of diluted magnetic semiconductors and anomalous Hall-voltage noise
The carrier spin and impurity spin densities in diluted magnetic
semiconductors are considered using a semiclassical approach. Equations of
motions for the spin densities and the carrier spin current density in the
paramagnetic phase are derived, exhibiting their coupled diffusive dynamics.
The dynamical spin susceptibilities are obtained from these equations. The
theory holds for p-type and n-type semiconductors doped with magnetic ions of
arbitrary spin quantum number. Spin-orbit coupling in the valence band is shown
to lead to anisotropic spin diffusion and to a suppression of the Curie
temperature in p-type materials. As an application we derive the Hall-voltage
noise in the paramagnetic phase. This quantity is critically enhanced close to
the Curie temperature due to the contribution from the anomalous Hall effect.Comment: 18 pages, 1 figure include
Optical properties of metallic (III,Mn)V ferromagnetic semiconductors in the infrared to visible range
We report on a study of the ac conductivity and magneto-optical properties of
metallic ferromagnetic (III,Mn)V semiconductors in the infrared to visible
spectrum. Our analysis is based on the successful kinetic exchange model for
(III,Mn)V ferromagnetic semiconductors. We perform the calculations within the
Kubo formalism and treat the disorder effects pertubatively within the Born
approximation, valid for the metallic regime. We consider an eight-band
Kohn-Luttinger model (six valence bands plus two conduction bands) as well as a
ten-band model with additional dispersionless bands simulating
phenomenologically the upper-mid-gap states induced by antisite and
interstitial impurities. These models qualitatively account for
optical-absorption experiments and predict new features in the mid-infrared
Kerr angle and magnetic-circular-dichroism properties as a function of Mn
concentration and free carrier density.Comment: 10 pages, 7 figures, some typos correcte
Heat transport in a Coulomb ion crystal with a topological defect
The thermodynamics of low-dimensional systems departs significantly from
phenomenologically deducted macroscopic laws. Particular examples, not yet
fully understood, are provided by the breakdown of Fourier's law and the
ballistic transport of heat. Low-dimensional trapped ion systems provide an
experimentally accessible and well-controlled platform for the study of these
problems. In our work, we study the transport of thermal energy in
low-dimensional trapped ion crystals, focusing in particular on the influence
of the Aubry-like transition that occurs when a topological defect is present
in the crystal. We show that the transition significantly hinders efficient
heat transport, being responsible for the rise of a marked temperature gradient
in the non-equilibrium steady state. Further analysis reveals the importance of
the motional eigenfrequencies of the crystal.Comment: 9 pages, 5 figure
Absence of skew scattering in two-dimensional systems: Testing the origins of the anomalous Hall effect
We study the anomalous Hall conductivity in spin-polarized, asymmetrically
confined two-dimensional electron and hole systems, focusing on skew-scattering
contributions to the transport. We find that the skew scattering, principally
responsible for the extrinsic contribution to the anomalous Hall effect,
vanishes for the two-dimensional electron system if both chiral Rashba subbands
are partially occupied, and vanishes always for the two-dimensional hole gas
studied here, regardless of the band filling. Our prediction can be tested with
the proposed coplanar two-dimensional electron/hole gas device and can be used
as a benchmark to understand the crossover from the intrisic to the extrinsic
anomalous Hall effect.Comment: 4 pages, 2 figures include
Doping dependence of the Neel temperature in Mott-Hubbard antiferromagnets: Effect of vortices
The rapid destruction of long-range antiferromagnetic order upon doping of
Mott-Hubbard antiferromagnetic insulators is studied within a generalized
Berezinskii-Kosterlitz-Thouless renormalization group theory in accordance with
recent calculations suggesting that holes dress with vortices. We calculate the
doping-dependent Neel temperature in good agreement with experiments for
high-Tc cuprates. Interestingly, the critical doping where long-range order
vanishes at zero temperature is predicted to be xc ~ 0.02, independently of any
energy scales of the system.Comment: 4 pages with 3 figures included, minor revisions, to be published in
PR
Medieneinsatz in der Eignungsdiagnostik:empirische Untersuchung zur Validität eines medial variierten Personalauswahlverfahrens
Die Anforderungen, welche an moderne Personalauswahlverfahren gestellt werden, sind vielschichtig. So sollten diese, neben einer hohen Objektivität, Zuverlässigkeit und Vorhersagegüte, auch in Bezug auf die wahrgenommene soziale Validität und Fairness höchsten Ansprüchen genügen. Einen möglichen Ansatz, um den oben genannten Forderungen gerecht zu werden, stellt der Einsatz von Multimedia dar. Mit der vorliegenden Arbeit wurde, motiviert durch positive Ergebnissen zu videobasierten SJTs, ein erster Versuch unternommen, eine Rollenspielübung in multimedialer, videobasierter Form abzubilden. Anhand des Vergleichs eines zu diesem Zweck konstruierten multimedialen Verfahrens mit einer herkömmlichen Rollenspielübung in Face-to-Face Form und einer Paper-Pencil Variante sollte die Frage beantwortet werden, inwieweit sich für das Rollenspiel eine Verbesserung der kriterienorientierten sowie der wahrgenommenen sozialen Validität und Fairness durch den Einsatz von Multimedia realisieren lässt
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