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Liquid nitrogen is commonly circulating through radiative panels which cover satellite supporting structure inside thermal vacuum test chamber. In the Large Space Simulator (LSS) located in the ESA* ESTEC** Test Centre, there is the need to move the satellite specimen inside the vacuum chamber to modify its relative orientation vis-a-vis the artificial sun beam. Re-orientation of the radiative panels is then required. ESA is currently developing a New Motion System (NMS) allowing dynamic motion from Gimbal to the Yoke Stand without any reconfiguration of the test. To do so, a nitrogen supply is required which can follow the rotation of the thermal shrouds under vacuum. Nitrogen flexible hoses are not anymore suitable due to their volume and mass constraints and due to the limitation in the rotation range. This paper describes the design, manufacturing and tests of a new compact multi-turn Rotary Nitrogen Joint (RNJ) compliant with thermal vacuum conditions used for spacecraft thermal testing. This prototype development is funded by the ESA Technology and Research Program. *European Space Agency **European Space Research and Technology Centre

SPICE is a high resolution imaging spectrometer operating at extreme ultraviolet wavelengths, 70.4 – 79.0 nm and 97.3 - 104.9 nm. It is a facility instrument on the Solar Orbiter mission. SPICE will address the key science goals of Solar Orbiter by providing the quantitative knowledge of the physical state and composition of the plasmas in the solar atmosphere, in particular investigating the source regions of outflows and ejection processes which link the solar surface and corona to the heliosphere. By observing the intensities of selected spectral lines and line profiles, SPICE will derive temperature, density, flow and composition information for the plasmas in the temperature range from 10,000 K to 10MK. The instrument optics consists of a single-mirror telescope (off-axis paraboloid operating at near-normal incidence), feeding an imaging spectrometer. The spectrometer is also using just one optical element, a Toroidal Variable Line Space grating, which images the entrance slit from the telescope focal plane onto a pair of detector arrays, with a magnification of approximately x5. Each detector consists of a photocathode coated microchannel plate image intensifier, coupled to active-pixel-sensor (APS). Particular features of the instrument needed due to proximity to the Sun include: use of dichroic coating on the mirror to transmit and reject the majority of the solar spectrum, particle-deflector to protect the optics from the solar wind, and use of data compression due to telemetry limitations.

Inflammatory bowel disease in interleukin 2 (IL-2) deficient (IL-2(-/-)) mice is triggered by the intestinal microflora and mediated by CD4(+) T cells.To determine the characteristics of microflora specific intestinal T cells, including migration and cytokine production.Intestinal T cell populations and cytokine mRNA expression of specific pathogen free (SPF) and germ free (GF) IL-2(-/-) and IL-2(+/+) mice were compared by flow cytometry and reverse transcription-polymerase chain reaction. Cytokine production of intestinal mononuclear cells on stimulation with microflora antigens was assessed by ELISA. In vivo migration of T cells was assessed by adoptive transfer of (51)Cr labelled CD4(+)CD25(-)alpha beta(+) T cells. The ability of intestinal T cell lines to promote colitis was determined by adoptive transfer experiments.SPF IL-2(-/-) mice produced higher interferon gamma (IFN-gamma) and tumour necrosis factor alpha mRNA levels than GF IL-2(-/-) mice, which was accompanied by an increased number of CD4(+)alpha beta T cells in the colon. Tracking of (51)Cr labelled and adoptively transferred T cells revealed an increased MAdCAM-1 dependent but VCAM-1 independent recruitment of these cells into the colon of SPF IL-2(-/-) mice. Colon lamina propria lymphocytes (LPL) from SPF IL-2(-/-) mice showed increased spontaneous IFN-gamma production in vitro. On stimulation with bacterial microflora antigens, intraepithelial lymphocytes and LPL did not produce IFN-gamma, but high quantities of IL-10, which did not suppress IFN-gamma production. Bacterial antigen specific cell lines established from colon LPL of SPF IL-2(-/-) mice with colitis showed a regulatory T cell-like cytokine profile and only marginally modulated the course of colitis and survival of IL-2(-/-) mice.Our results suggest that microflora reactive regulatory T cells are present in the colon of SPF IL-2(-/-) mice. However, IL-10 produced by these cells did not significantly modulate a possible secondary proinflammatory CD4 Th1 cell population to produce IFN-gamma.