The Early Local and Regional Immune Response to Recall Inoculations of Mycobacterium Leprae in the Skin of Rhesus Macaques (Macaca Mulatta).

Epidemiological studies have failed to show any important impact of human immunodeficiency virus (HIV) infection and disease on leprosy, in contrast to the well documented increase in incidence and morbidity with other mycobacteria in these patients, notably Mycobacterium tuberculosis. The early events following exposure and repeated exposure to Mycobacterium leprae (ML) have not still been studied. Previous studies of first inoculations of ML in the skin of rhesus monkeys have indicated delayed recruitment of CD4+ cells and delayed interleukin (IL) 2 secretion in skin inoculation sites in simian immunodeficiency (SIV) positive animals. The development of the secondary immune response against a challenge of ML was studied over a period of 2 months in the skin of 9 rhesus macaques, all inoculated previously with ML, 3 of which were SIV positive slow progressors. Cell recruitment and types of cytokine response in the skin and draining lymph nodes (LN) were investigated using flow cytometry (FC), immunohistochemistry, and reverse transcription polymerase chain reaction to detect relative levels of messenger ribonucleic acid (mRNA) expression for IL2, IL4, interferon gamma (IFNgamma) and IL10. Results were analyzed according to SIV status and persistence of ML infection. An early vigorous expression of IL2 and IFNgamma mRNA, indicative of a strong T helper (Th) 1 cytokine profile, was seen in the skin of macaques that cleared ML infection. Animals that developed persistent ML infection (ML+) had delayed, weak Th1 response, and no evidence of early Th2 response in the skin. In contrast, early up regulation of IL4 was only observed in the LN of ML+ macaques. Recruitment of CD4+ lymphocytes into the skin was significantly lower and delayed in ML+ animals. CD4:CD8 ratio were significantly lower in the blood in SIV+ monkeys. However, no significant differences in CD4+ lymphocyte recruitment or expression of cytokine mRNA were observed between SIV- and SIV+ monkeys. Despite evidence of systemic immunodepression, the slow progressing SIV+ rhesus macaques are still capable of mounting an adequate response to ML re-inoculation in the skin. A Th2 response is not generated in the skin early after re-infection in animals which developed progressive infection

Switchable Windows - Spectral Transmission and Switching Times

The switching time and spectral transmission in fully clear and fully opaque states of polymer dispersed liquid crystals (PDLC), suspended particle device (SPD) and electrochromic (EC) switchable windows were evaluated to assess their suitability to control solar heat transmission though glazed façade and comfort to building occupants. The transmission measurement on a SPD film showed a very effective absorption modulation in the visible range but fast decrease in the near infrared region. The switching speed was demonstrated to be related strongly to wavelengths. A SPD film with a larger absorption and faster switching speed in the infrared region was shown to be preferable to control solar heat transfer through glazings and thermal comfort. The PDLC window did not modulate transmission but rather modulated scattering. In the opaque state, the PDLC window was highly scattering resulting in spectral transmission varying at short distances from the window while being constant in the far field. The switching speed measurement demonstrated that liquid-based switchable windows can respond as fast as the eye to have the potential to control spontaneous glare. The EC window demonstrated a lower absorbance efficiency than the SPD in the visible range but appeared to have a much higher efficiency in the infrared region measured. EC windows are characterized by their slow switching speed when compared to SPD and PDLC. This makes them unsuitable for spontaneous glare control and are more suited to predictive solar heat gain control over a defined time horizon. With the increasing integration of adaptive technologies into building facades and to predict the energetical and ambient performance of such buildings and the impact on the occupants’ comfort, this paper emphasises on the importance to provide spectral performance information of switchable windows

Discreteness effects in a reacting system of particles with finite interaction radius

An autocatalytic reacting system with particles interacting at a finite distance is studied. We investigate the effects of the discrete-particle character of the model on properties like reaction rate, quenching phenomenon and front propagation, focusing on differences with respect to the continuous case. We introduce a renormalized reaction rate depending both on the interaction radius and the particle density, and we relate it to macroscopic observables (e.g., front speed and front thickness) of the system.Comment: 23 pages, 13 figure

Emergence of pulled fronts in fermionic microscopic particle models

We study the emergence and dynamics of pulled fronts described by the Fisher-Kolmogorov-Petrovsky-Piscounov (FKPP) equation in the microscopic reaction-diffusion process A + A A$ on the lattice when only a particle is allowed per site. To this end we identify the parameter that controls the strength of internal fluctuations in this model, namely, the number of particles per correlated volume. When internal fluctuations are suppressed, we explictly see the matching between the deterministic FKPP description and the microscopic particle model.Comment: 4 pages, 4 figures. Accepted for publication in Phys. Rev. E as a Rapid Communicatio

A Review of Control Methodologies for Dynamic Glazing

With adaptive building façade technologies, a building envelope can provide a comfortable indoor environment under varying external conditions with minimal additional heating or cooling. The control strategy applied to the adaptation of the façade is a key determining factor in the successful integration of these technologies into a building. The building envelope plays a key role in regulating light, heat and mass transfer from the outdoor environment to the indoor. Dynamic glazing can be used to adjust the amount of solar radiation entering a building. The control strategies that ultimately determine the success of these switchable technologies to affect a building’s energy performance and occupant comfort are reviewed in this paper

Ultraviolet Radiation Constraints around the Circumstellar Habitable Zones

Ultraviolet radiation is known to inhibit photosynthesis, induce DNA destruction and cause damage to a wide variety of proteins and lipids. In particular, UV radiation between 200-300 nm becomes energetically very damaging to most of the terrestrial biological systems. On the other hand, UV radiation is usually considered one of the most important energy source on the primitive Earth for the synthesis of many biochemical compounds and, therefore, essential for several biogenesis processes. In this work, we use these properties of the UV radiation to define the bounderies of an ultraviolet habitable zone. We also analyze the evolution of the UV habitable zone during the main sequence stage of the star. We apply these criteria to study the UV habitable zone for those extrasolar planetary systems that were observed by the International Ultraviolet Explorer (IUE). We analyze the possibility that extrasolar planets and moons could be suitable for life, according to the UV constrains presented in this work and other accepted criteria of habitability (liquid water, orbital stability, etc.).Comment: 34 pages, 8 figures Accepted for publication by Icaru

High reflectivity grating waveguide coatings for 1064nm

We propose thin single-layer grating waveguide structures to be used as high-reflectivity, but low thermal noise, alternative to conventional coatings for gravitational wave detector test mass mirrors. Grating waveguide (GWG) coatings can show a reflectivity of up to 100% with an overall thickness of less than a wavelength. We theoretically investigate GWG coatings for 1064nm based on tantala (Ta2O5) on a Silica substrate focussing on broad spectral response and low thickness

Elastic fluctuations as observed in a confocal slice

Recent confocal experiments on colloidal solids motivate a fuller study of the projection of three-dimensional fluctuations onto a two-dimensional confocal slice. We show that the effective theory of a projected crystal displays several exceptional features, such as non-standard exponents in the dispersion relations. We provide analytic expressions for the effective two-dimensional elastic properties which allow one to work back from sliced experimental observations to three-dimensional elastic constants.Comment: 5 pages, 2 figure

Toward the reflectance measurement of micro components

Today, the controls by reflection of optical coatings are most of the time made with flat samples thanks to commercial spectrophotometers. However, components become smaller and more complex, curvature radius of lenses or mirrors are larger, so that measures are not so accurate and sometimes are not possible. Flat samples don’t represent anymore the real reflection ability of the component. So to perform this kind of measurements, special devices are needed. A new means developed by the French Atomic Energy Commission (CEA) is proposed to fill in this gap. This device has a accuracy of 0.06% on flat sample over the 400 nm to 950 nm wavelength range with a spot size of 100 mm. It can measure the reflectance of samples even if their shapes are spherical. We investigate stainless steel balls and optical micro components (mirrors and lens) thanks to the tiny size of the analyzing spot of our reflectometer. Herein we introduce our first results on small optical components and show the limiting factors of our device