Pliocene and Pleistocene chronostratigraphy and paleoenvironment of the Central Arctic Ocean, using deep water agglutinated foraminifera

Deep-water agglutinated foraminifera (DWAF) were studied from Cores PS2177-5, PS2200-5, PS2212-3 and PS2185-6; from the R/V POLARSTERN ARK-VIII/3 Cruise in the central Arctic Ocean. The sediments were non-calcareous containing a sparse assemblage of eleven DWAF species. A chronostratigraphic framework is presented for Cores PS2200-5 and PS2185-6. Paleoenvironmental data suggests a bathyal environment (2000-4000m) affected by water masses in the Arctic Ocean. The taxonomy of all of the DWAF found is presented and illustrated. A new species of the Family Trochamminidae; Trochammina lomonosovensis n. sp. is described and illustrated

Stress-dependent local oxidation of silicon

The two-dimensional isolation oxidation of silicon is considered for stress-dependent reaction and diffusion coefficients. The influence of such parameters is investigated numerically and asymptotically in the bird's beak problem and for curved geometries arising in the oxidation of cylindrical and spherical structures. In the bird's beak problem, the limit of large activation volume is described for a stress-dependent reaction coefficient, illustrating the significant growth retardation of the silicon/silicon oxide interface and reduced stresses in the silicon oxide. Novel high-order nonlinear evolution-type PDEs are derived and investigated using asymptotic and numerical techniques

Indication of Non-equilibrium Transport in SiGe p-MOSFETs

No abstract avaliable

Enhanced velocity overshoot and transconductance in Si/Si(0.64)Ge(0.36)/Si pMOSFETs - predictions for deep submicron devices

No abstract avaliable

Equivalence of two approaches for the inhomogeneous density in the canonical ensemble

In this article we show that the inhomogeneous density obtained from a density-functional theory of classical fluids in the canonical ensemble (CE), recently presented by White et al [Phys. Rev. Lett. 84 (2000) 1220], is equivalent to first order to the result of the series expansion of the CE inhomogeneous density introduced by Gonzalez et al [Phys. Rev. Lett. 79 (1997) 2466].Comment: 6 pages, RevTe

A reduction in long-term spatial memory persists after discontinuation of peripubertal GnRH agonist treatment in sheep

Chronic gonadotropin-releasing hormone agonist (GnRHa) administration is used where suppression of hypothalamic-pituitary-gonadal axis activity is beneficial, such as steroid-dependent cancers, early onset gender dysphoria, central precocious puberty and as a reversible contraceptive in veterinary medicine. GnRH receptors, however, are expressed outside the reproductive axis, e.g. brain areas such as the hippocampus which is crucial for learning and memory processes. Previous work, using an ovine model, has demonstrated that long-term spatial memory is reduced in adult rams (45 weeks of age), following peripubertal blockade of GnRH signaling (GnRHa: goserelin acetate), and this was independent of the associated loss of gonadal steroid signaling. The current study investigated whether this effect is reversed after discontinuation of GnRHa-treatment. The results demonstrate that peripubertal GnRHa-treatment suppressed reproductive function in rams, which was restored after cessation of GnRHa-treatment at 44 weeks of age, as indicated by similar testes size (relative to body weight) in both GnRHa-Recovery and Control rams at 81 weeks of age. Rams in which GnRHa-treatment was discontinued (GnRHa-Recovery) had comparable spatial maze traverse times to Controls, during spatial orientation and learning assessments at 85 and 99 weeks of age. Former GnRHa-treatment altered how quickly the rams progressed beyond a specific point in the spatial maze at 83 and 99 weeks of age, and the direction of this effect depended on gonadal steroid exposure, i.e. GnRHa-Recovery rams progressed quicker during breeding season and slower during non-breeding season, compared to Controls. The long-term spatial memory performance of GnRHa-Recovery rams remained reduced (P < 0.05, 1.5-fold slower) after discontinuation of GnRHa, compared to Controls. This result suggests that the time at which puberty normally occurs may represent a critical period of hippocampal plasticity. Perturbing normal hippocampal formation in this peripubertal period may also have long lasting effects on other brain areas and aspects of cognitive function

Rotational Seismology and Engineering Applications: Proceedings for the First International Workshop Menlo Park, California, U.S.A.—September 18 to 19, 2007

In our recent study of a seven-story reinforced concrete hotel in Van Nuys, California, which was damaged during Northridge 1994, earthquake, we showed that the prediction of where the localized damage may occur should be carried out by non-linear wave propagation methods (Gicev and Trifunac 2006). In this paper we describe how the rotations (local strains and drifts) in the building, depend upon the distribution of the stiffness along the building height, nonlinear properties of the reinforced concrete, and the nature of strong motion. To search for the optimum performance parameters, we vary the distribution of the velocity of propagation of SH waves from story to story. Five hypothetical buildings with: sinusoidal, linear, concave quadratic parabola, convex quadratic parabola and cubic parabola stiffness distributions, together with the actual distribution observed in the structure are considered. It is shown that the maximum rotations appear in the actual building, while the minimum rotations occur for the buildings with velocity distributions described by cubic parabola and quadratic convex parabola (maximum stiffness at the bottom) distributions. It is concluded that the design of the seven-story reinforced concrete hotel was not optimal. For design of new structures and for retrofit of old ones near faults, the stiffness distributions should resemble the cubic parabola or quadratic convex parabola distributions

The phase free, longitudinal, magnetic component of vacuum electromagnetism

A charge $q$ moving in a reference laboratory system with constant velocity {\bf V} in the $X$-axis produces in the $Z$-axis a longitudinal, phase free, vacuum magnetic field which is identified as the radiated ${\bf B}^{(3)}$ field of Evans, Vigier and others.Comment: ReVTeX file, 7pp., no figure

Pattern matching and pattern discovery algorithms for protein topologies

We describe algorithms for pattern matching and pattern learning in TOPS diagrams (formal descriptions of protein topologies). These problems can be reduced to checking for subgraph isomorphism and finding maximal common subgraphs in a restricted class of ordered graphs. We have developed a subgraph isomorphism algorithm for ordered graphs, which performs well on the given set of data. The maximal common subgraph problem then is solved by repeated subgraph extension and checking for isomorphisms. Despite the apparent inefficiency such approach gives an algorithm with time complexity proportional to the number of graphs in the input set and is still practical on the given set of data. As a result we obtain fast methods which can be used for building a database of protein topological motifs, and for the comparison of a given protein of known secondary structure against a motif database

Tunneling and Metastability of continuous time Markov chains

We propose a new definition of metastability of Markov processes on countable state spaces. We obtain sufficient conditions for a sequence of processes to be metastable. In the reversible case these conditions are expressed in terms of the capacity and of the stationary measure of the metastable states