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Optical pump-terahertz probe spectroscopy has become a widely used experimental tool for the investigation of the ultrafast far-infrared response of polar systems. In this paper the authors present an analytical method of calculating the propagation of ultrashort terahertz pulses in photoexcited media. The transient terahertz wave form transmitted through the sample is equal to a product of the in
The aggregating proteoglycans (aggrecan, versican, neurocan, and brevican) are important components of many extracellular matrices. Their N-terminal globular domain binds to hyaluronan, but the function of their C-terminal region containing a C-type lectin domain is less clear. We now report that a 90-kDa protein copurifies with recombinant lectin domains from aggrecan and versican, but not from t
The lilioid herb, Anthericum ramosum, occurs in four geographically-isolated regions (Sjaelland, Skane, Oland and Gotland) in Denmark and southern Sweden. We investigated allozyme variation at nine polymorphic loci in A. ramosum from 16 sites (33 populations) in the four regions. There was no clear overall geographic pattern of differentiation between the regions, but the southernmost Gotland and
Recently, primitive human bone marrow (BM) progenitors supporting hematopoiesis in extended (>60 days) long-term BM cultures were identified. Such extended long-term culture-initiating cells (ELTC-IC) are of the CD34(+)CD38(-) phenotype, are quiescent, and are difficult to recruit into proliferation, implicating ELTC-IC as the most primitive human progenitor cells detectable in vitro. However, it
The behavior of microstructurally short inherent cracks within a preoxidized thermal barrier coating system upon thermal shock loading is considered. A thin alumina oxide layer holding residual stresses was induced at the ceramic/metal interface to simulate thermally grown oxide on the bond coat. Undulation of the oxidized bond coat was modeled as a sinusoidal surface. The variations of the stress
An investigation of the lifetime of the 3d(9)4s D-3(3) level along a part of the nickel-like isoelectronic sequence has been performed. The focus of this work has been to evaluate the importance of the hyperfine induced electric quadrupole channel of the 3d(10) S-1(0)-3d(9)4s D-3(3) transition for isotopes with nuclear spin. Comparisons between the magnetic octupole transition rate and the hyperfi
We study the rapid decrease of peak gain in resonant-phonon THz Quantum Cascade Lasers with increasing temperature. The effect of various microscopic scattering processes on the gain profile as a function of temperature is discussed. We argue that increased broadening, prim arily due to increased impurity scattering, and not diminishing population inversion, is the main reason for the reduction o
Streptomycetes are mycelial bacteria that resemble filamentous fungi in their apical growth, branching, and morphogenetic development. One inroad into the largely unknown mechanisms underlying this prokaryotic growth polarity is provided by Streptomyces DivIVA, a protein localized at hyphal tips and involved in tip extension. Another aspect is a proposed migration of nucleoids. During sporulation,
The structure and stability of the lamellar liquid crystal formed by the surfactant sodium bis-2ethylhexyl sulfosuccinate (AOT) in water is perturbed by small amounts of the substituted acrylamides N-isopropyl, N,N-diethyl, N-acryloylmorpholine, and N,N-dimethyl methacrylamide, as revealed by small angle X-ray scattering (SAXS), deuterium NMR, and microscopy. These molecules are water soluble and
Current treatments of osteoarthritis (OA) focus on pain and loss of joint function. When these interventions fail, the destroyed joint is replaced by implants of metal, plastic and ceramics. In the future, we need to detect cartilage loss before it is too severe, prevent further loss and stimulate regrowth of lost cartilage. Research in tissue engineering can help us understand the complex require
Albinism in birds is thought to result from the expression of recessive alleles that disrupt melanin pigmentation at feather development. We have studied great reed warblers Acrocephalus arundinaceus in a recently founded and increasing population in Sweden during 15 years for the presence of birds with albinistic feathers. The study population was founded in 1978 and the few cases of albinism was
This paper presents some improvements of the differential equation algorithm for transmission line protection. The improvements are: fault classification; new filtering; new algorithm for three-phase faults. Simulation results indicate a nominal operation time of 5-7 ms for three-phase faults and slightly higher for other fault types.
Glucagon-like peptide-1 (GLP-1), a future treatment for type 2 diabetes, is efficiently degraded by the enzyme dipeptidyl peptidase IV (DPP IV), yielding the major metabolite GLP-1-(9-36)-amide. In this study, we examined the potential glucose lowering effect of GLP-1(9-36)-amide in mice and found that GLP-1-(9-36)-amide (3 and 10 nmol/kg) did not affect insulin secretion or glucose elimination wh
Machine learning clustering techniques are used to characterize and, after the training phase, to identify phases within an ignition process. Forth e ethanol mechanism used in this paper, four physically identifiable phases were found and characterized: the initiation phase, preignition phase, ignition phase, and the postignition phase. The clustering is done with respect to fuzzy logic predicates
1. We investigated age-related changes in two reproductive traits (laying date and annual fecundity) in barn swallows Hirundo rustica L. using a mixed model approach to di-stinguish among between- and within-individual changes in breeding performance with age. 2. We tested predictions of age-related improvements of competence (i.e. constraint hypothesis) and age-related progressive disappearance o
