Design and verification of the Far Ultraviolet Spectrographic Imager (FUV-SI) for the IMAGE mission

peer reviewedThe IMAGE FUV-SI is simultaneously imaging auroras at 121.8 nm and 135.8 nm. The spectrograph design challenge is the efficient rejection of the intense Lyman-alpha emission at 121.6 nm while passing its Doppler-shifted component at 121.8 nm. The FUV-SI opto-mechanical design, analysis integration, and verification of performances against environment are discussed in this paper. In absence of STM environmental constraints at subsystem levels are derived analytically from F.E.M. and used for pre-qualifying optical subsystems

Farmer seed networks make a limited contribution to agriculture? Four common misconceptions

The importance of seed provisioning in food security and nutrition, agricultural development and rural livelihoods, and agrobiodiversity and germplasm conservation is well accepted by policy makers, practitioners and researchers. The role of farmer seed networks is less well understood and yet is central to debates on current issues ranging from seed sovereignty and rights for farmers to GMOs and the conservation of crop germplasm. In this paper we identify four common misconceptions regarding the nature and importance of farmer seed networks today. (1) Farmer seed networks are inefficient for seed dissemination. (2) Farmer seed networks are closed, conservative systems. (3) Farmer seed networks provide ready, egalitarian access to seed. (4) Farmer seed networks are destined to weaken and disappear. We challenge these misconceptions by drawing upon recent research findings and the authors’ collective field experience in studying farmer seed systems in Africa, Europe, Latin America and Oceania. Priorities for future research are suggested that would advance our understanding of seed networks and better inform agricultural and food policy

Enabling planetary science across light-years. Ariel Definition Study Report

Ariel, the Atmospheric Remote-sensing Infrared Exoplanet Large-survey, was adopted as the fourth medium-class mission in ESA's Cosmic Vision programme to be launched in 2029. During its 4-year mission, Ariel will study what exoplanets are made of, how they formed and how they evolve, by surveying a diverse sample of about 1000 extrasolar planets, simultaneously in visible and infrared wavelengths. It is the first mission dedicated to measuring the chemical composition and thermal structures of hundreds of transiting exoplanets, enabling planetary science far beyond the boundaries of the Solar System. The payload consists of an off-axis Cassegrain telescope (primary mirror 1100 mm x 730 mm ellipse) and two separate instruments (FGS and AIRS) covering simultaneously 0.5-7.8 micron spectral range. The satellite is best placed into an L2 orbit to maximise the thermal stability and the field of regard. The payload module is passively cooled via a series of V-Groove radiators; the detectors for the AIRS are the only items that require active cooling via an active Ne JT cooler. The Ariel payload is developed by a consortium of more than 50 institutes from 16 ESA countries, which include the UK, France, Italy, Belgium, Poland, Spain, Austria, Denmark, Ireland, Portugal, Czech Republic, Hungary, the Netherlands, Sweden, Norway, Estonia, and a NASA contribution

Agronomic importance of Fusarium culmorum : occurrence, diversity and resistance to triazole fungicides

A variety of Fusarium spp. can infect wheat ears leading to a fungal disease known has Fusarium head blight (FHB), which is associated with yield losses and mycotoxins accumulation. The occurrence of Fusarium spp. and their related mycotoxins was monitored from 2010 to 2013 in wheat fields to evaluate the risk caused by FHB in Belgium. The most prevalent species were F. graminearum, F. avenaceum, F. poae and F. culmorum, with large variations between years and locations. Deoxynivalenol (DON), nivalenol (NIV), enniatins and moniliformin were found in every field in various concentrations, whereas beauvericin was more scarcely detected. The presence of each toxin was tightly correlated with the presence of at least one Fusarium spp. Fusarium culmorum was the most prevalent species in 2011 and was associated with high NIV concentrations in the grains. This species showed a broad spectrum of resistance levels to triazole fungicides, which did not appear to be correlated to its high genetic diversity. Interestingly, the strains producing NIV were significantly more resistant than the DON-producing ones. A F. culmorum strain resistant to DMI was therefore produced in vitro from the sensitive strain UK99 to understand the genetic basis of the observed resistance phenomenon. The analysis of its transcriptomic response to tebuconazole allowed identifying an overexpressed drug-efflux transporter. The implication of this transporter in triazole resistance was subsequently confirmed in resistant strains isolated from fields. This thesis brings new insights on FHB epidemiology in Belgium and on resistance mechanisms developed by fungal populations in response to fungicides.(AGRO - Sciences agronomiques et ingénierie biologique) -- UCL, 201

Vertical distributions of Fusarium spp. infections on mature wheat ears under natural field conditions

Wheat spikes have a vertical architecture, presenting multiple spikelets on which Fusarium spp. infectious propagules can land, initiate grain infection and possibly spread into the rachis to infect neighboring kernels. However, it is not known whether fungal infections occur randomly along the ear nor if species naturally interact within the ear. Over 4 years, five wheat fields in Belgium were surveyed annually and Fusarium spp. were isolated from kernels sampled from three positions on the ears (top, middle and bottom). This study revealed a vertical gradient of infection by Fusarium spp., with more isolates recovered from the bottom than from the top of the ears. This observation could result from infections by an inoculum from the ground, a downward movement of propagules present on the ear surface carried by rain and/or a downward spread of the fungus within the rachis. Moreover, multiple infected kernels originating from the same spike were frequent but, in most cases, the same species could be isolated from those grains and almost no relationships were observed among species present on the same spikes. Therefore, Fusarium spp. infections on wheat ears occur preferentially at the bottom of the spike and independently of the other species present

Patent: Method for forming a hermetically sealed cavity - EP 1 840 081 B1

European patent EP 1 840 081 B1status: publishe

Method for forming a hermetically sealed cavity (United States Patent No US 8,062,497 B2)

One inventive aspect relates to a method for forming hermetically sealed cavities, e.g. semiconductor cavities comprising fragile devices, MEMS or NEMS devices. The method allows forming hermetically sealed cavities at a controlled atmosphere and pressure and at low temperatures, for example, at temperatures not exceeding about 200° C. The method further allows forming sealed cavities with short release times, for example, release times of about a few minutes to 30 minutes. The method may, for example, be used for zero level packaging of MEMS or NEMS devices.status: publishe

Les cahiers du sergent Walter / Pierre Loevenbruck et Pierre Hellin ; lettre-préface du général Gouraud

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