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Usefulness and pitfalls of planar gamma-scintigraphy for measuring aerosol deposition in the lungs: a Monte Carlo investigation

Planar gamma-scintigraphy is often used to quantify pulmonary deposition patterns from aerosol inhalers. The results are quite different from those obtained using 3-dimensional PET and SPECT. The purpose of this study was to characterize the effects of scatter and tissue attenuation on the distribution of radiolabeled aerosol as measured by planar scintigraphy using Monte Carlo simulations. This s

Titanium incorporation and Ti-VI(3+)-Ti-IV(4+) charge transfer in synthetic diopside

A series of Ti-doped diopside samples synthesized by fluxgrowth methods under reducing conditions were investigated by microanalytical methods and optical absorption spectroscopy, to assess Ti incorporation mechanisms, valence states, and related electronic transitions. Chemical characterization show that Ti occurs both in the tri-and tetravalent states, with Ti4+ preferentially ordered to the tet

Humoral immune response to conserved epitopes of Chlamydia trachomatis and human 60-kDa heat-shock protein in women with pelvic inflammatory disease

The association between humoral immunity to unique and conserved epitopes of the Chlamydia trachomatis 60-kDa heat-shock protein (hsp60) and immunity to human hsp60 was examined in 129 women with laparoscopically verified pelvic inflammatory disease. An ELISA was used to detect antichlamydial IgG and IgA antibodies, IgG antibodies to recombinant human hsp60, and antibodies to two synthetic peptide

Duality between cost and density in optimal control

A theorem on duality between cost functions and density functions in optimal control is derived using the Hahn-Banach theorem. The result puts focus on convexity aspects in control synthesis and the theory of almost global stability. In particular, it gives a new proof that existence of a density function is both necessary and sufficient for almost global stability in a nonlinear system.

Performance evaluation of list sequence MAP decoding

List-sequence (LS) decoding has the potential to yield significant coding gain additional to that of conventional single-sequence decoding, and it can be implemented with full backward compatibility in systems where an error-detecting code is concatenated with an error-correcting code. LS maximum-likelihood (ML) decoding provides a list of estimated sequences in likelihood order. For convolutional

Computer supported visualisation of quality systems developed by network teams

This paper reports a pilot study and three case studies to examine aimed at studying if a quality system, according to the ISO 9000 quality standard, can be visualised, exploring how the visualisation should be designed in order to support continuous improvements and evaluating the design process for development of prototypes. By discussing with the research team, three companies in southern Swede

A method of lean air-fuel ratio control using combustion pressure measurement

In this paper a method for control of air–fuel ratio (AFR) in cold or lean-burning spark-ignited engines is investigated. The technique uses combustion pressure as measured by a cylinder-mounted sensor, and is based on the phenomenon of increasing cycle-to-cycle combustion pressure variation as the air–fuel mixture approaches the limits of flammability. The cylinder pressure is measured from one e

The arthropod community of Scots pine (Pinus sylvestris L.) canopies in Norway

We summarise the findings of arthropods collected by fogging the canopy of 24 pine trees in two sites in Eastern and Western Norway. From the samples, taken in 1998 and in 1999, almost 30,000 specimens were determined to 512 species, with Diptera being most species rich (210 species), followed by Coleoptera (76 species) and Araneae (49 species). Of the 96 new species records, nine were new to scie

Conflict Prevention from a Nordic Perspective: Putting Prevention into Practice

Since conflict prevention is a visionary strategy it has beer difficult to put it into practice. This article explores conflict prevention in practice as well as in theory. There have been several attempts by the international community to take a proactive rather than a reactive approach to conflict management. One case often held up as a model for post Cold War prevention is the preventive missio

Simulations of the phonon Bragg switch in GaAs

It has recently been proposed that X-rays can be switched on sub-picosecond time-scales by using laser-generated coherent optical phonons: The so called phonon Bragg switch. We present here detailed simulations of the efficiency of such a switch by solving the time-dependent generalized Takagi-Taupin equations utilizing a perturbative approach. We explore the switching efficiency in diffraction fr

Hedgehog, but not Odd skipped, induces segmental grooves in the Drosophila epidermis.

The formation of segmental grooves during mid embryogenesis in the Drosophila epidermis depends on the specification of a single row of groove cells posteriorly adjacent to cells that express the Hedgehog signal. However, the mechanism of groove formation and the role of the parasegmental organizer, which consists of adjacent rows of hedgehog- and wingless-expressing cells, are not well understood

Electrical "wiring" of viable Gluconobacter oxydans cells with a flexible osmium-redox polyelectrolyte

An application of a flexible polyvinylimidazole osmium functionalised polymer for efficient electrical wiring of whole Gluconobacter oxydans cells is described. The performance of the redox polymer as a mediator for intact bacterial cells was tested with glucose, ethanol and glycerol, typical substrates of the periplasmically localised PQQ-dependent membrane bound dehydrogenases. The efficiency of

Stratospheric ozone, ultraviolet radiation, and cryptogams

The stratospheric ozone layer, which protects the biosphere from biologically active (mostly harmful) ultraviolet-B (UV-B) solar radiation, thinned during the latter half of the 20th century. In this paper some of the effects of UV-B radiation on cryptogams (cyanobacteria, algae, lichens, mosses, liverworts, pteridophytes and fungi) are reviewed. Effects vary among species, and therefore changes i

Nanoconfinement-enhanced conformational response of single DNA molecules to changes in ionic environment

We show that the ionic environment plays a critical role in determining the configurational properties of DNA confined in silica nanochannels. The extension of DNA in the nanochannels increases as the ionic strength is reduced, almost tripling over two decades in ionic strength for channels around 100x100 nm in dimension. Surprisingly, we find that the variation of the persistence length alone wit

Modification of Charge Transfer and Energy Level Alignment at Organic/TiO2 Interfaces

Adsorption of titanyl phthalocyanine (TiOPc) on rutile TiO2(110) modified by a set of pyridine derivatives (2,2'-bipyridine, 4,4'-bipyridine, and 4-tert-butyl pyridine) has been investigated using synchrotron radiation based X-ray photoelectron spectroscopy (XPS). For the unmodified TiOPc/TiO2 system, a strong charge transfer is observed from the first layer TiOPc into the substrate, which leads t

Virtual pedagogical agents: Naturalism vs. stylization

In discussions on naturalism vs. stylization in the design of virtual pedagogical agents (VPAs), the smooth communication argument is one of the most central in favour of visual naturalism. Yet, this argument dissolves if we separate design into the levels of: (l) linguistic performance, where the support for naturalism is strong; (2) dynamic visual appearance, in the sense of bodily behaviour, wi

Transcriptional upregulation and unmethylation of the promoter region of p16 in invasive basal cell carcinoma cells and partial co-localization with the gamma2 chain of laminin-332.

Basal cell carcinoma cells show low proliferation rates at the invasive front and a concordant upregulation of the cdk-inhibitor p16, limiting proliferative capacity. Little is known about the mechanisms of p16 regulation in normal and malignant cells apart from that many transcription factors such as Ets1, Ets2, SP1, SP3, JunB and the polycomb protein Bmi1 have the potential to induce or repress

Biglycan organizes collagen VI into hexagonal-like networks resembling tissue structures.

The ability of the leucine-rich repeat (LRR) proteins biglycan, decorin and chondroadherin to interact with collagen VI and influence its assembly to supramolecular structures was studied by electron microscopy and surface plasmon resonance measurements in the BIAcore 2000 system. Biglycan showed a unique ability to organize collagen VI into extensive hexagonal-like networks over a time period of

On the global existence of solutions to quasilinear parabolic equations

We prove, under quite general assumptions, the global existence of classical solutions for quasilinear parabolic equations in bounded domains with homogeneous Dirichlet boundary conditions. The same results for weakly coupled reaction-diffusion systems are also given. 2000 Mathematics Subject Classification.