Mast cells generated from patients with atopic eczema have enhanced levels of granule mediators and an impaired Dectin-1 expression.

BACKGROUND: The disrupted skin barrier of patients with atopic eczema (AE) might facilitate contact between mast cells (MCs) in the skin and environmental triggers of the disease. One such trigger is the skin-colonizing yeast Malassezia sympodialis (M. sympodialis). In this study, we investigated the interaction of MC with M. sympodialis. METHODS: Mast cells were generated from peripheral blood CD34(+) progenitor cells of healthy controls (HC) and M. sympodialis-sensitized AE patients. Biopsy specimens were taken from HC and lesional AE skin for immunohistological stainings. RESULTS: The progenitor-derived MCs expressed the macrophage-inducible C-type lectin receptor Mincle, and exposure of these cells to M. sympodialis induced up-regulation of the mRNA expression of Mincle. Furthermore, we demonstrate that, when compared to HC, the progenitor-derived MCs from AE patients (i) contain more intrinsic granule mediators such as histamine, (ii) exhibit enhanced IL-6 release in response to M. sympodialis exposure, and (iii) have an impaired up-regulation of the fungal recognition receptor Dectin-1. In addition, analysis of skin sections from HC and AE patients revealed MCs as the predominant Dectin-1-expressing cell type in the skin. CONCLUSION: Our data indicate that progenitor-derived MCs from AE patients differ from those from HC. Further investigations with skin-derived MCs are necessary to confirm the observed differences which could provide new insights into the pathogenic mechanisms underlying AE.

Environmentally friendly use of non-coal ashes in Sweden.

The Swedish Thermal Engineering Research Institute (Värmeforsk) initiated an applied research program "Environmentally friendly use of non-coal ashes", in 2002. The program aims at increasing knowledge on the by-products of energy production and their application. The goal of formulating technical and environmental guidelines and assessments is a major point of the program, which is supported by about forty authorities and private organisations. The programme has been divided into four areas: recycling of ashes to forests, geotechnical applications, use in landfilling, and environmental aspects and chemistry. Among all results obtained, the following progress is shown: *Evidence for the positive effects of spreading ashes on forest growth. *A proposal for environmental guidelines on the utilisation of ashes in construction. *A handbook for using non-coal fly ashes in unpaved roads. *Technical and environmental assessments of MSWI bottom ashes in road construction. *Development of the use of ashes with municipal wastewater sludge as a cover for landfills and mine tailings. *Use of ashes from bio-fuels in concrete and replacement of cement in stoop mining. *A method to classify those by-products from combustion that have mirror entries in the EWC as a hazardous or non-hazardous compound. The Ash Programme has also made it possible to increase knowledge on ashes as valuable materials, on quality assurance and on markets for recovered materials.

High-energy X-ray optics with silicon saw-tooth refractive lenses.

Silicon saw-tooth refractive lenses have been in successful use for vertical focusing and collimation of high-energy X-rays (50-100 keV) at the 1-ID undulator beamline of the Advanced Photon Source. In addition to presenting an effectively parabolic thickness profile, as required for aberration-free refractive optics, these devices allow high transmission and continuous tunability in photon energy and focal length. Furthermore, the use of a single-crystal material (i.e. Si) minimizes small-angle scattering background. The focusing performance of such saw-tooth lenses, used in conjunction with the 1-ID beamline's bent double-Laue monochromator, is presented for both short ( approximately 1:0.02) and long ( approximately 1:0.6) focal-length geometries, giving line-foci in the 2 microm-25 microm width range with 81 keV X-rays. In addition, a compound focusing scheme was tested whereby the radiation intercepted by a distant short-focal-length lens is increased by having it receive a collimated beam from a nearer (upstream) lens. The collimation capabilities of Si saw-tooth lenses are also exploited to deliver enhanced throughput of a subsequently placed small-angular-acceptance high-energy-resolution post-monochromator in the 50-80 keV range. The successful use of such lenses in all these configurations establishes an important detail, that the pre-monochromator, despite being comprised of vertically reflecting bent Laue geometry crystals, can be brilliance-preserving to a very high degree.

On the electronic coupling of the C=O stretching vibrations in Cl(2)Pt(malonate)(-).

Ab initio calculations on the complex Cl(2)Pt(malonate)(-) have been performed to estimate the magnitude and the source of the splitting between the symmetric and antisymmetric C=O stretches. It is shown that a large part of the splitting can result from pure electronic coupling mediated via the pi-structure of the ligand. Calculations have also been performed on the free ligand malonate(-) and the neutral malonaldehyde that show decreasing electronic coupling, which is consistent with the decreasing resonance stabilization. A simple effective C=O interaction potential has been produced for Cl(2)Pt(malonate)(-) that is used to estimate the electronic splitting of the 1600 cm(-1) IR band to 137 cm(-1). Anharmonic contributions seem to reduce this value somewhat, but the magnitude and sign of the splitting is similar to the experimental value of 183 cm(-1) found for the similar Cl(2)Pt(acac)(-) complex.

International round-robin experiment to test the International Organization for Standardization total-scattering draft standard.

An international round-robin experiment has been conducted among laboratories in different countries to test the measurement and the data-analysis procedures in the International Organization for Standardization draft standard ISO/DIS 13696 for measuring total scattering from low-scatter laser optics. Ten laboratories measured total backscattering from high-reflectance mirrors, 50% beam splitters, and antireflection-coated windows. Results were sent to the Laser Zentrum Hannover, which acted as coordinator and analyzed all the backscattering data. The results showed that the procedure in the draft standard was useful for measuring and reporting backscattering for low-scatter optics. Problems encountered in the round-robin experiment included the accumulation of particles on the surfaces, particularly on the high-reflectance mirrors.

TiN-alloy coatings for temperature control of space vessels.

The problem of combining the temperature control of a space vehicle with the mechanical and chemical stability of the surface is addressed. With the absorption of solar radiation and the emission of thermal radiation considered the static and dominant factors that determine the equilibrium temperature of a spherical object, a simple model is formulated. Realistic variations of the two material-dependent parameters, solar absorptance alpha and hemispherical emittance epsilon, permit a large change in the equilibrium temperature, from less than -50 to more than +150 degrees C. It is pointed out that for a generalized gray surface, i.e., one made from a material whose reflectance-emittance has the same value within the visible and the thermal wavelength regions, the equilibrium temperature is approximately 5 degrees C, independent of the numerical value of the reflectance. With the requirement for electrical conductivity also taken into account, TiN alloys are identified as candidate materials. Measurements and calculations of some of them indicate that this group may contain a material that fulfills all the requirements. The experimental reflectance spectrum is used in estimating the equilibrium temperature for different TiN alloys; one Ti-Al-N-alloy with a gradient content of Al is found to have the lowest equilibrium temperature, 66 degrees C.

Temperature dependence of the band emittance for nongray bodies.

The general problem of obtaining correct emittance values from broadband IR radiometric measurements on nongray samples is discussed. If the spectral emittance has structure in a band, the emittance, averaged over that band, will be temperature dependent, even if the spectral emittance is insensitive to the temperature change. We point out that a widely used expression, with correction for radiance from the surroundings reflected by the sample, is valid only if the spectral emittance is temperature and wavelength independent, i.e., gray. If the spectral emittance is nongray, the conventional emission factor, as determined by a broadband radiometer, is temperature dependent and the numerical value is significantly different from the averaged band emittance sought. Two algorithms are suggested to extract the correct band-averaged emittance from the temperature-dependent radiometric emission factor obtained with the conventional expression. The algorithms are demonstrated with a step model for the spectral emittance, and it is shown that the agreement with the correct average band emittance is significantly improved.

Optical constants and Drude analysis of sputtered zirconium nitride films.

Opaque and semitransparent dc magnetron-sputtered ZrN films on glass and silicon have been optically characterized with spectral reflectance measurements and ellipsometry. High rate sputtered ZrN has good optical selectivity, i.e., higher than 90% infrared reflectance and a pronounced reflectance step in the visible to a reflectance minimum of less than 10% at 350 nm. The results are comparable with those obtained for single crystalline samples and those prepared by chemical vapor deposition. The complex optical constant (N = n v ik) for opaque films has been determined in the 0.23-25-µm wavelength range with Kramers-Kronig integration of bulk reflectance combined with oblique incidence reflectance for p-polarized light. A variable angle of incidence spectroscopic ellipsometer has been used for determination of the optical constants in the 0.28-1.0-µm wavelength region. The results of the two methods show excellent agreement. The results indicate that ZrN is free electronlike and the Drude model can be applied. The best opaque films had Drude plasma energies (hω(p) between 6.6 and 7.5 eV and relaxation energies (h/τ) between 0.29 and 0.36 eV. Ellipsometer data for the semitransparent films show that the refractive index (n) in the visible increases with decreasing film thickness whereas the extinction coefficient (k) is essentially unchanged. The optical properties are improved by deposition upon a heated substrate.

Reststrahlen band studies of polycrystalline beryllium oxide.

New experimental bulk reflectance and emittance spectra from the 9-15-µm reststrahlen band region of polycrystallline beryllium oxide are reported. Note that the polycrystalline material exhibits a dip at 10 pm, which is not present in spectra for single crystals. The possible origins of this feature are discussed including absorption by a surfaceboscillation excited at boundaries of 20-µm crystalline grains. Owing to the reststrahlen band, beryllium oxide is selectively low, emitting in the primary atmospheric window, which makes this material useful for frost prevention when electrical conductors cannot be used. This protection is susceptible to reduction by surface contaminants from air pollution. Using an established acceleration procedure, we simulated such pollution, and the increase in emittance was measured. It was observed that the emissivity increased from 0.31 for a clean surface to 0.36 for a surface heavily polluted by an industrial atmosphere.

Infrared optical constants of polycrystalline boron nitride: comment.

In contrast to statements in a recent article by M. Khelkhal and F. Herlemont [Appl. Opt. 32, 57-59 (1993)], it is pointed out that well-documented IR data exist for boron nitride in both the cubic and hexagonal phases. Furthermore, the existence of a strong reststrahlen band causes a significant dispersion over the wavelength region of 1-10 µm.

Determination of interface roughness by using a spectroscopic total-integrated-scatter instrument.

A spectroscopic total-integrated-scatter instrument has been constructed. It uses a Coblentz sphere for the collection of the scattered light and a lamp with a monochromator as a light source. It can be used to measure diffuse reflectance as well as transmittance. The instrument has been used to measure diffuse reflectance of thermally and chemical-vapor-deposition oxidized silicon wafers. Comparisons are made with measurements by using a spectrophotometer with an integrating sphere. The data have been interpreted with a parameterized model for light scattering from a double layer, to obtain rms surfaceroughness values for the two interfaces of the oxide film.

Reststrahlen material bilayers: an option for tailoring in the infrared.

Double-layer interference calculations are used to show that the frost-preventing properties of insulating beryllium oxide can be improved. An underlying substrate of cubic boron nitride, which has a short-wavelength reststrahlen band, will reduce the thermal radiation leak of beryllium oxide in the 8-9.5 interval. The interference calculations for these highly dispersive and partly absorbing materials demonstrate that the configuration with beryllium oxide as an outer layer is essential for the performance. Less than 20% average emittance and 11 W/m(2) irradiance in the 8-13-µm window is predicted when an optimum thickness of 2.5-µm beryllium oxide upon cubic boron nitride is used.

Beryllium oxide: a frost-preventing insulator.

A method is suggested of achieving low outdoor radiative losses by low spectral emittance in the atmospheric window of 8-13 microm, which will reduce dew and frost formation on surfaces exposed to the clear sky. The use of this selectively low emittance makes it feasible to use electrically insulating materials. It is argued that lattice-based reststrahlen bands can be exploited for this purpose. The observation is made that hexagonal beryllium oxide has a strong reststrahlen band that covers most of the primary atmospheric window. Results from experiments with polycrystalline samples demonstrate that bulk beryllium oxide is equally effective for dew and frost prevention as glass coated with conducting tin oxide.

Optical scattering from oxidized metals. 1: Model formulation and properties.

Strong scattering, which exhibits a conspicuous wavelength dependence, has been experimentally observed from certain oxidized metals. A model is presented which combines the effects of interface illumination in a new normalization procedure with the scalar scattering reduction of the Fresnel interface reflectance coefficients. The model is used to calculate the specular and the diffuse part of the hemispheric reflectance from the double layer, with oxide thickness and rms roughness as input parameters. The results give a qualitatively correct spectral variation and underline the importance of the substrate reflectance. The results also illustrate an interesting difference in scattering behavior, whether the front surface or the oxide-metal interface is rough.

Optical scattering from oxidized metals. 1: Model formulation and properties; errata.

This erratum Letter draws attention to an omission and an error in the original submission.

Optical scattering from oxidized metals. 2: Model verification for oxidized copper.

A model for the calculation of diffuse reflectance spectra for oxidized metals is applied to thermally oxidized copper films and compared with experiments. The model calculations reproduce the spectral structure observed in the experiments. It is demonstrated that the air-oxide interface roughness dominates the scattering for wavelengths shorter than the absorption threshold of the oxide, and the oxide-metal interface roughness dominates for longer wavelengths. Using the model for fitting calculations the rms roughness values for the two interfaces are determined independently. The roughness values agree with the results from high accuracy stylus profiling of the oxide front surface as well as stylus profiling and total integrated scattering of He-Ne light from the bare metal surface, obtained after etching away the oxide. The good overall agreement between the calculated and experimental diffuse reflectance spectra, as well as the rms roughness values determined with different techniques, confirms the applicability of the model.

Anomalies in integrating sphere measurements on structured samples.

Anomalies are reported in total and diffuse reflectance values obtained from measurements on structured samples with a double-beam integrating sphere. It is demonstrated that these anomalies are caused by an interplay between the sample structure and geometric sphere imperfections. The sample structure causes a confinement of the diffuse reflectance which may suffer port losses as well as erroneously high signal levels. This can lead to deviations in the recorded reflectance values as high as 50%.

Interpretation of integrating sphere signal output for non-Lambertian samples.

A new formalism is derived for the analysis of signal output from double-beam integrating spheres. The analysis explicitly considers the effects of port losses and a non-Lambertian sample surface and introduces a separation of the diffusely reflected light into two parts: one which should be analyzed as a specular component and one which is fully diffuse. An experimental procedure to determine the two parameters in the formalism is described for two cases, a brushed copper and a rolled aluminum surface, and it is experimentally verified that the formalism eliminates spurious structure from the barium sulfate reference. A criterion is also given for the selection of barium sulfate or polytetrafluorethylene powder as a reference material.

Determination of the SiO(2)/Si interface roughness by diffuse reflectance measurements.

The problem of determining the roughness of the SiO(2)/Si interface is treated. A model is used based on the Fresnel formalism and scalar scattering theory. The resulting formulas express the diffuse reflectance as a function of the optical constants of the two materials, the oxide thickness and the rms roughness of the interfaces. Using the roughness values as adjustable parameters, quantitative information about the interface roughness is obtained from the diffuse reflectance spectra for an SiO(2)/Si double layer. Excellent agreement between calculated and experimental spectra is obtained for an rms roughness of 9.0 nm at the front surface and 2.2 nm at the oxide substrate interface for the case of a low-pressure low-temperature CVD film of SiO(2) on Si.