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See detailCryo-optical testing of large aspheric reflectors operating in the sub mm range
Roose, Stéphane ULg; Houbrechts, Yvette ULg; Mazzoli, Alexandra ULg et al

in Zhang, Y.; Jiang, W.; Cho, M. (Eds.) Proceedings of the 2nd SPIE symposium on Advanced Optical Manufacturing and Testing Technologies (2005, August)

The cryo-optical testing of the PLANCK primary reflector (elliptical off-axis CFRP reflector of 1550 mm x 1890 mm) is one of the major issue in the payload development program. It is requested to measure ... [more ▼]

The cryo-optical testing of the PLANCK primary reflector (elliptical off-axis CFRP reflector of 1550 mm x 1890 mm) is one of the major issue in the payload development program. It is requested to measure the changes of the Surface Figure Error (SFE) with respect to the best ellipsoid, between 293 K and 50 K, with a 1 μm RMS accuracy. To achieve this, Infra Red interferometry has been used and a dedicated thermo mechanical set-up has been constructed. This paper summarises the test activities, the test methods and results on the PLANCK Primary Reflector - Flight Model (PRFM) achieved in FOCAL 6.5 at Centre Spatial de Liege (CSL). Here, the Wave Front Error (WFE) will be considered, the SFE can be derived from the WFE measurement. After a brief introduction, the first part deals with the general test description. The thermo-elastic deformations will be addressed: the surface deformation in the medium frequency range (spatial wavelength down to 60 mm) and core-cell dimpling. [less ▲]

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See detailCryogenic and Thermal Control for Vacuum Facilities Development in KARI
Guiot, Marc ULg; Jamotton, Pierre ULg; Grodent, Christophe ULg et al

in CURRAN (Ed.) 26th Aerospace Testing Seminar 2011: Los Angeles, California, USA, 29 - 31 March 2011 (2011, March 29)

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See detailCryogenic Zone Compression for the Measurement of Dioxins
Focant, Jean-François ULg; Patterson Jr

Scientific conference (2010, April)

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See detailCryogenic Zone Compression for the Measurement of Dioxins in Human Serum at Attogram Level by GCxGC-IDHRMS.
Patterson Jr; Welch; Turner et al

Conference (2008, June)

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See detailCryopréservation d’ovocytes et d’embryons par congélation ou vitrification dans le cadre de l’assistance médicale à la procréation
Vanderzwalmen, Pierre ULg; Ectors, Fabien ULg; Papras, Y et al

in Poncelet, Christophe; Sifer, Christophe (Eds.) Physiologie, pathologie et thérapie de la reproduction chez l’humain (2011)

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See detailCryopreservation des embryons humains par vitrification.
Vanderzwalmen, Pierre ULg; Zech, Nicolas; Greindl, A.-J. et al

in Gynécologie Obstétrique & Fertilité (2006), 34(9), 760-9

Vitrification is a cryopreservation strategy where cells are converted into a glass-like amorphous solid which is free of any crystalline structure. Such process is achieved by a combination of high ... [more ▼]

Vitrification is a cryopreservation strategy where cells are converted into a glass-like amorphous solid which is free of any crystalline structure. Such process is achieved by a combination of high concentration of cryoprotectant and an extremely high cooling rate. In the last years, survival rates of up to 80% after thawing and pregnancy rates of almost 30% could be achieved after transfer of vitrified embryos at the zygote, cleavage, morula and blastocyst stages. Also deliveries of healthy babies have been reported numerous times. To this day, a limited interest in this technique can be noted. The explanation may lye in the apprehension of many ART units regarding exposure of embryos to high concentrations of cryoprotectants and storage in non sterile conditions. The aim of the first part of this article, is to analyse if such fears are justified on the basis that vitrification mimics conditions already in use for many years in slow-cooling procedures where cells are plunged into liquid nitrogen at around -30 degrees C and secondly since storage of embryos are now possible in high aseptic conditions. In the second part, results on survival after thawing, pregnancy rates and baby take home rates of vitrified embryos will be presented and the problems associated with vitrification of blastocysts will be discussed. [less ▲]

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See detailCryopreservation For The Elimination Of Cucumber Mosaic And Banana Streak Viruses From Banana (Musa Spp.)
Helliot, Bertrand; Panis, B.; Poumay, Y. et al

in Plant Cell Reports (2002), 20(12), 1117-1122

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See detailCryopreservation of embryos : a way to reduce the number of housed animals and the genetic drift.
Remy, Benoît ULg; Ectors, Fabien ULg; Drion, Pierre ULg

Poster (2014, January 27)

The GIGA Mouse facility platform has recently improved its mouse line cryopreservation technique. The method of embryo cryopreservation by rapid cooling also called aseptic vitrification has been selected ... [more ▼]

The GIGA Mouse facility platform has recently improved its mouse line cryopreservation technique. The method of embryo cryopreservation by rapid cooling also called aseptic vitrification has been selected. Vitrification media, key steps and timing have been optimized and validated. After a first partial exposition of the embryos to cryoprotective solutions, they are immersed in a vitrifying mixture of penetrating and non-penetrating cryoprotectants for a short time. The straw containing the embryos is immediately sealed before to be plunged in LN2, resulting in a brutal solidification in which crystallization does not have time to occur. [less ▲]

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See detailCryopreservation of Radopholus similis, a tropical plant-parasitic nematode
Elsen, Annemie; Ferrandis Vallterra, Salvador ULg; Van Wauwe, Tom et al

in Cryobiology (2007), 55(2), 148-157

For obligate plant-parasitic nematodes, cryopreservation has advantages over the usual preservation methods on whole plants or axenic culture systems, because the latter two are labourious and time and ... [more ▼]

For obligate plant-parasitic nematodes, cryopreservation has advantages over the usual preservation methods on whole plants or axenic culture systems, because the latter two are labourious and time and space consuming. In addition, cross contamination among different isolates can occur easily. Moreover, specific genetic studies require maintenance of the original population. The nematode under investigation, Radopholus similis, is a plant-parasitic nematode from the humid tropics. Therefore, any treatment at low temperatures is likely to add extra stress to the nematode, making the development of a cryopreservation protocol extremely difficult. In this paper, we describe experiments to achieve a successful cryopreservation protocol for the tropical nematode R. similis using vitrification solution-based methods based on a well defined mixture of cryoprotectants in combination with ultra-rapid cooling and thawing rates. A two-step treatment was used consisting of an incubation in glycerol followed by the application of a vitrifying mixture of methanol, glycerol and glucose. After cryopreservation, the athogenicity of the nematodes was not altered, since they could infect and reproduce on carrot discs after recovery in the Ringer solution. The cryopreservation method described can be used for routine cryopreservation of R. similis lines from different origins. [less ▲]

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See detailCryoscopie des solides de l’organisme. Procédés et résultats
Fredericq, Léon ULg

in Bulletin de l'Académie Royale de Médecine de Belgique (1902), (novembre),

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See detailCryoscopy: a novel enhancing method of in vivo skin imaging.
Nikkels, Arjen ULg; Pierard, Gérald ULg

in Skin Research & Technology (2007), 13(4), 377-84

BACKGROUND: It is a common observation that superficial freezing of normal skin and skin tumors may create a transient superficial whitening effect. In this respect, cryoscopy refers to the direct ... [more ▼]

BACKGROUND: It is a common observation that superficial freezing of normal skin and skin tumors may create a transient superficial whitening effect. In this respect, cryoscopy refers to the direct observation by dermoscopy, with or without digital recording, of the visual alterations of the frozen tissues. AIMS: To define the optimal method of cryoscopy and to describe the cryoscopy patterns of normal skin and selected skin lesions. MATERIALS AND METHODS: The influence of (a) different cryogenic sources [solid carbon dioxide (-78.5 degrees C), liquid nitrogen (N(2), -196 degrees C), and a mixture of dimethyl ether and propane (-57 degrees C)], (b) various application methods (spraying, cotton chill tips, copper plate), and (c) freezing time was assessed with regard to clinical feasability, visualization quality, and persistance time of the whitening effect. Cryoscopy patterns of normal skin, callosities and of histologically proven seborrheic keratoses, verrucous hamartomas, molluscum contagiosum, keratoacanthomas, viral warts, condylomas, actinic keratoses, dermatofibromas, skin tags, basal cell carcinomas, angiomas, and melanocytic naevi were assessed. RESULTS: The cryoscopy images of skin highlighted the skin lines. They appeared similar regardless of the freezing source and the application method. The aspects differed according to the nature of the lesions. The cotton chill tip method provided a longer whitening period compared with the other cold sources, both in normal and lesional skin. Hence, it represented the most convenient way for performing digital recording cryoscopy. On normal skin, cryoapplication was limited to about 1.5 s due to pain, resulting in whitening times ranging from 6 to 9 s, which was too short for easy digital recording. On all studied skin tumors, a 10-s N(2) freezing time was not experienced as painful, and blanching time persisted for 20-34 s, allowing easy digital recording. The whitening time was longer with increasing freezing time on both normal and lesional skin. Every single examined normal skin site and all the skin lesions showed a strong whitening effect, except heavily cornified structures, including some keratoses, callosities, and viral warts. Increased contrast of the skin surface texture was observed in almost every studied lesion. CONCLUSION: The N(2) cotton chill tip technique appeared to be the most convenient technique for cryoscopy and provided longer whitening periods compared with the other freezing sources. Pain prevented its use on normal skin, but a series of exophytic skin lesions was conveniently accessible to cryoscopy. The differences in whitening periods of various epidermal components resulted in increased visual contrast, creating typical cryoscopy images for the different exophytic skin tumors. Cryoscopy represents a novel in vivo skin imaging technique that is rapid, non-invasive, cost-effective, and easily performed. It shows both investigative and diagnostic potentials. It is remarkable that cryoscopy pictures closely resemble those yielded by skin capacitance imaging. [less ▲]

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See detailCryothérapie et maladies rhumatismales
Demoulin, Christophe ULg; Vanderthommen, Marc ULg

in Revue du Rhumatisme (2011), 78

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See detailCryotherapy in rheumatic diseases
Demoulin, Christophe ULg; Vanderthommen, Marc ULg

in Joint Bone Spine (2012), 79

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See detailCryptic diversity in brevipalpus mites (tenuipalpidae)
Navia, D.; Mendonça, R. S.; Ferragut, F. et al

in Zoologica Scripta (2013), 42(4), 406-426

Defining the taxonomic identity of organisms is a prerequisite for their study, and in the case of economically important species, misidentification may lead to the application of inappropriate prevention ... [more ▼]

Defining the taxonomic identity of organisms is a prerequisite for their study, and in the case of economically important species, misidentification may lead to the application of inappropriate prevention and control strategies. Flat mites of the Brevipalpus genus include several crop pests and the systematics of these mites represents a challenge for acarologists. Many of the most economically important Brevipalpus species have repeatedly been inaccurately identified. Such problematic classification has been attributed to the likely occurrence of cryptic species in the genus. In this study, we used an integrative approach that combined molecular analyses, including sequence-based species delimitation, with detailed morphological identification using traits that have recently showed to be taxonomically informative. Sequences of mitochondrial cytochrome c oxidase subunit I (COI) were obtained from individuals collected from host plants belonging to 14 genera and 13 families across 29 locations in the Americas (Brazil, Chile, USA). The phylogenetic analyses included previously published Brevipalpus sequences from GenBank, and the final data set was classified into 44 haplotypes. Six putative species were recognised by COI-based species delimitation analysis, and morphological evidence supported each of these species. The integrative approach revealed the occurrence of cryptic species in the Brevipalpus genus and contributed to the clarification of previously noted incongruences. The results presented here allow for the evaluation of taxonomic characteristics in a phylogenetic context and indicate new characters for the differentiation of Brevipalpus species. In addition, Brevipalpus incognitus n. sp. Ferragut & Navia, a cryptic species detected in this study, is described based on morphological and molecular traits. Implications of the advances in Brevipalpus systematics presented herein with respect to pest management are briefly discussed. © 2013 The Norwegian Academy of Science and Letters. [less ▲]

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See detailCryptic taxa should have names. Reflections in the glasswort genus Salicornia (Amaranthaceae)
Kadereit, G; Piraiinen; Lambinon, Jacques ULg et al

in Taxon (2012), 61

Detailed reference viewed: 33 (4 ULg)