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We study a class of model prototype hybrid systems comprised of a microscopic Arrhenius surface process describing adsorption/desorption and/or surface diffusion of particles coupled to an ordinary differential equation displaying bifurcations triggered by the microscopic process. The models proposed here are caricatures of realistic systems arising in diverse applications ranging from surface pro

A new matrix product is defined and its properties are investigated. The commutatuion matrix which flips a left direct product of two matrices into a right direct one is derived as a composition of two identity matrices. The communication matrix is a special case of the direct product permuting matrices defined in this paper which are matrix representations of the permutation operators on tensor s

Certain structures of heparan sulfate (HS) inhibit cell proliferation of fibroblasts. Whether this inhibition is dependent on inhibition of mitogenic signaling pathways or nuclear translocation of HS is unknown. In this study we investigated possible mechanism(s) and structural requirements by which antiproliferative glycosaminoglycans exert their effects on mitogen-activated protein kinase (MAP k

In recent years evidence has emerged that the amount of isoprene emitted from a leaf is affected by the CO2 growth environment. Many - though not all - laboratory experiments indicate that emissions increase significantly at below-ambient CO2 concentrations and decrease when concentrations are raised to above-ambient. A small number of process-based leaf isoprene emission models can reproduce this

The strains in matrix and hydrides around a fatigue crack tip grown in situ in a single-edge notched specimen of hydrided Zircaloy-4 have been determined using synchrotron X-ray diffraction at various stages of loading. The hydride phase shows proportionally larger strains at full load compared to the matrix strain. The residual strains of the matrix ahead of the crack tip reveal the reverse plast

Atypical lipomatous tumor (ALT) is an intermediate malignant mesenchymal tumor that is characterized by supernumerary ring chromosomes and/or giant rod-shaped marker chromosomes (RGMC). Fluorescence in situ hybridization ( FISH) and molecular genetic analyses have disclosed that the RGMCs always contain amplified sequences from the long arm of chromosome 12. Typically, RGMCs are the sole clonal ch

Two cooking liquors and a black liquor were fractionated by ultrafiltration. The liquors were withdrawn from different stages in a kraft pulp mill employing continuous digestion. The ultrafiltration was performed at 90 degrees C with two ceramic membranes with cut-offs of 5 kDa and 15 kDa. Only small differences in membrane performance were observed when concentrating the three liquors to 90% volu

Purpose To investigate whether previously observed correlations between tumor karyotype and risk of metastases could be reproduced in an independent set of high-grade soft tissue sarcomas (STSs). Patients and Methods In a previous study on high-grade STSs with clonal chromosome aberrations, we identified a number of cytogenetic variables, besides tumor grade and size, that were associated with sig

The vehicle ingress and egress are important issues for the automotive industry, both for minimizing assembly work load and for maximizing end-users’ comfort. Digital human modeling tools are used for evaluating and visualizing these issues. The assembler and end-user are more or less performing the very same entering task if the vehicles have identical geometrical prerequisites. The major differe

Variations in total heart volume (atria plus ventricles) during a cardiac cycle affect efficiency of cardiac pumping. The goals of this study were to confirm the presence, extent, and contributors of total heart volume variation during the cardiac cycle in healthy volunteers with the use of MRI. Eight healthy volunteers were examined by MRI at rest. Changes in total cardiac volume throughout the c

An algorithm is presented in which the Colour-Dipole Cascade Model as implemented in the Ariadne program is corrected to match the fixed order tree-level matrix elements for e e(+) --> n jets. The result is a full parton level generator for e e(+) annihilation where the generated states are correct on tree-level to fixed order in alpha(s) and to all orders with modified leading logarithmic (MLLA)

Although colour polymorphisms in adult organisms of many taxa are often adaptive in the context of sexual selection or predation, genetic correlations between colour and other phenotypic traits expressed early in ontogeny could also play an important role in polymorphic systems. We studied phenotypic and genetic variation in development time among female colour morphs in the polymorphic damselfly

Objectives: To estimate the dietary intakes of heterocyclic amines (HCAs), to examine the intakes in relation to socio-economics, lifestyle and other dietary factors and to compare the classification of subjects by intake of HCA versus intake of meat and fish. Design: Cross-sectional analysis within the Malmo Diet and Cancer (MDC) cohort. Data were obtained from a modified diet history, a structur

The Prototype Repository, at the Aspo HRL (Hard Rock Laboratory), is a demonstration project for the deposition of spent nuclear fuel, and provides a full-scale reference for testing predictive models relating to a spent nuclear fuel repository, both its individual components as well as the complete system. The final layout involves six deposition holes, four in an inner section and two in an oute

We have studied the formation of ohmic contacts to InAs nanowires by chemical etching and passivation of the contact areas in an ammonium polysulfide, (NH4)(2)S-x, water solution. The nanowires were exposed to different dilution levels of the (NH4)(2)Sx solution before contact metal evaporation. A process based on a highly diluted ( NH4)S-2(x) solution was found to be self-terminating, with minima

Recent progress in studies of animal flight mechanics is reviewed. A range of birds, and now bats, has been studied in wind tunnel facilities, revealing an array of wake patterns caused by the beating wings and also by the drag on the body. Nevertheless, the quantitative analysis of these complex wake structures shows a degree of similarity among all the different wake patterns and a close agreeme

A packed column has been used to study the absorption of nitrogen oxide in an alkaline solution of potassium permanganate. The reactions taking; place during the absorption have been examined and the rate constants have been estimated from experimental data. The experiments show that potassium permanganate is an excellent absorbent for nitrogen oxide. However, to avoid formation of MnO2, the hydro

More than 40 years of revegetation using mainly Artemisia ordosica, Hedysarum scoparium, and Caragana korshinskii at Shapotou Desert Experimental Research Station near Lanzhou has established a dwarf-shrub and herbaceous cover on the stabilized sand dunes. The evapotranspiration (ET) of the xerophyte dwarf-shrub A. ordosica plant vegetation was measured by the autoweighing lysimeter method during

Objective: We investigated whether newborns respond differently to novel and deviant sounds during quiet sleep. Methods: Twelve healthy neonates were presented with a three-stimulus oddball paradigm, consisting of frequent standard (76%), infrequent deviant (12%), and infrequent novel stimuli (12%). The standards and deviants were counterbalanced between the newborns and consisted of 500 and 750 H