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Motivated by the classical picture of heat flow, we construct a stationary temperature gradient in a relativistic microscopic transport model. Employing the relativistic Navier-Stokes ansatz, we extract the heat conductivity K for a massless Boltzmann gas using only binary collisions with isotropic cross sections. We compare the numerical results to analytical expressions from different theories and discuss the final results. The directly extracted value for the heat conductivity can be referred to as a literature reference within the numerical uncertainties. [ABSTRACT FROM AUTHOR]

Abstract: Ultra-thin organic hetero-layers consisting of tin-phthalocyanine (SnPc) and 1,3,4,8-perylen-tetracarboxylicacid dianhydride (PTCDA) adsorbed on a Ag(111) surface are characterized with photoelectron spectroscopy (PES) and near edge X-ray absorption fine structure (NEXAFS) spectroscopy. If SnPc is deposited on the Ag(111) substrate, which is precovered with one monolayer of PTCDA, a well defined interface is formed with a closed SnPc wetting layer as can be derived from angle dependent core level and from valence photoelectron spectra. Moreover, X-ray absorption data show that the molecules are lying flat and that the bonding at the SnPc/PTCDA interface is weak. [ABSTRACT FROM AUTHOR]

Fungi from approximately 1700 individual arthropods that had been captured in traps set in aspen-dominated woodland in western Canada and baited with coyote dung, moose dung, white-rotted wood, brown-rotted wood and fiberglass were isolated in pure culture and identified. These data were analysed with principal components analysis (PCA) to determine whether different types of substrate attracted specific arthropods and whether these animals carried unique assemblages of fungi with known proclivities for the new habitat. Mycobiotic agar was used to restrict the numbers of fungi isolated and resulted in the recovery of 1687 isolates representing 65 species across 12 orders. Isolates of cosmopolitan fungal taxa such as species of Cladosporium, Penicillium, and Beauveria were the most numerous. Taxa with predilections for specific substrates, such as Myxotrichum and Cryptendoxyla that are known inhabitants of cellulose-rich materials (i.e. rotted wood), and various representatives of the keratinophilic Onygenales were recovered from arthropods attracted respectively to baits rich in cellulose and keratin. When traps were analysed according to the identity and numbers of arthropods captured, there was considerable overlap among clusters representing specific bait types, with traps baited with coyote dung being the most divergent partly because they captured significantly more arthropods than those baited with moose dung or rotted wood. When bait type was examined according to the identity and numbers of fungi on trapped arthropods the degree of overlap was also high although a few trends could be discerned. In particular traps baited with brown-rotted wood and coyote dung diverged slightly indicating that arthropods visiting these bait types were carrying somewhat different suites of fungi. [ABSTRACT FROM AUTHOR]

Cryptendoxyla hypophloia is a rarely reported cleistothecial ascomycete that has a cephalothecoid peridium comprising six to eight plates that split apart at maturity to expose the ascospores. Three new isolates from the bodies of live-trapped insects represent circumstantial evidence supporting an older hypothesis that this fungus is dispersed by arthropods and provided fresh material in which to examine the development of the ascocarp and its unusual active dehiscence mechanism. Vegetative hyphae envelop coiled gametangia to form the earliest stages of the development of the peridium and then accommodate the increasing volume of the expanding centrum tissues by branching and tip growth. Peridial plates are defined early in ascocarp ontogeny and at maturity consist of thick-walled, radially arranged hyphae that have transverse wall thickenings. Cells between plates and underlying dehiscence lines are thin walled. On drying, the radially arranged hyphae of the outer peridial layer contract, rupturing the thin-walled cells around the periphery of each plate along previously formed dehiscence lines. As plates flatten and evert, the ascocarp opens to expose the ascospores, ostensibly for pickup by arthropod carriers. Meristematic growth could not be confirmed in the developing ascocarps of C. hypophloia even though it has been implicated in the growth of the peridium in other cephalothecoid taxa. [ABSTRACT FROM AUTHOR]

Studies variations in cytokine mRNA expression during normal human pregnancy. Disease activity of T cell-mediated, organ-specific autoimmune diseases; Online reverse transcriptase-polymerase chain reaction technique; Serum hormone levels during pregnancy.

Coherent phonons are an excellent tool to investigate the interplay between electronic and structural dynamics. The displacive excitation of coherent phonons in elemental bismuth is one of the most widely studied processes for this purpose. We employ time-resolved photoelectron diffraction to access the structural dynamics by recording the photoemission intensity from one initial state as a function of emission angle. In comparison with tight-binding and single-scattering cluster calculations, this allows electronic and structural effects to be disentangled. Hence, the full dynamics of the hot electron gas and of coherently excited phonons can be accessed in a single experiment. As a major result the phase lag between the coherent phonons and the modulation of the electronic structure can be determined with high precision. The phonon phase lag with respect to the modulation of the electronic structure is about 2.85±0.21 rad, thus significantly smaller than π. The difference is not due to phonon decay by energy dissipation into low-energy modes, but rather caused by the very early evolution of the highly excited electron distribution. [ABSTRACT FROM AUTHOR]

What is the spatiotemporal limit of a macroscopic model that describes the optoelectronic interaction at the interface between different media? This fundamental question has become relevant for time-dependent photoemission from solid surfaces using probes that resolve attosecond electron dynamics on an atomic length scale. We address this fundamental question by investigating how ultrafast electron screening affects the infrared field distribution for a noble metal such as Cu(111) at the solid-vacuum interface. Attosecond photoemission delay measurements performed at different angles of incidence of the light allow us to study the detailed spatiotemporal dependence of the electromagnetic field distribution. Surprisingly, comparison with Monte Carlo semiclassical calculations reveals that the macroscopic Fresnel equations still properly describe the observed phase of the 1R field on the Cu(111) surface on an atomic length and an attosecond time scale. [ABSTRACT FROM AUTHOR]

We present our attoline which is a versatile attosecond beamline at the Ultrafast Laser Physics Group at ETH Zurich for attosecond spectroscopy in a variety of targets. High-harmonic generation (HHG) in noble gases with an infrared (IR) driving field is employed to generate pulses in the extreme ultra-violet (XUV) spectral regime for XUV-IR cross-correlation measurements. The IR pulse driving the HHG and the pulse involved in the measurements are used in a non-collinear set-up that gives independent access to the different beams. Single attosecond pulses are generated with the polarization gating technique and temporally characterized with attosecond streaking. This attoline contains two target chambers that can be operated simultaneously. A toroidal mirror relay-images the focus from the first chamber into the second one. In the first interaction region a dedicated double-target allows for a simple change between photoelectron/photoion measurements with a time-of-fight spectrometer and transient absorption experiments. Any end station can occupy the second interaction chamber. A surface analysis chamber containing a hemispherical electron analyzer was employed to demonstrate successful operation. Simultaneous RABBITT measurements in two argon jets were recorded for this purpose. [ABSTRACT FROM AUTHOR]

In the past, identification of the ingredients responsible for cosmetic allergic reactions was hampered by the difficulty of obtaining ingredient information for individual marketed cosmetic products, as of December 1980. Although some cosmetic companies provided ingredient information for their products, most required that an individual letter be written for each product. Since 1978, the U.S. regulations have required that all ingredients, except components of flavours and fragrances be declared on cosmetic product labels.

In the past, identification of the ingredients responsible for cosmetic allergic reactions was hampered by the difficulty of obtaining ingredient information for individual marketed cosmetic products, as of December 1980. Although some cosmetic companies provided ingredient information for their products, most required that an individual letter be written for each product. Since 1978, the U.S. regulations have required that all ingredients, except components of flavours and fragrances be declared on cosmetic product labels.