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See detailHigher-Moment Risk Exposures in Hedge Funds
Lambert, Marie ULg; Hübner, Georges ULg; Papageorgiou, Nicolas

Conference (2012, April)

The paper singles out the key roles of US equity skewness and kurtosis in the determination of the market premia embedded in Hedge Fund returns. We propose a conditional higher-moment asset pricing model ... [more ▼]

The paper singles out the key roles of US equity skewness and kurtosis in the determination of the market premia embedded in Hedge Fund returns. We propose a conditional higher-moment asset pricing model with location, trading and higher-moment factors in order to describe the dynamics of the Equity Hedge (Market Neutral, Short Selling and Long/Short strategies), Event Driven, Relative Value, and Funds of Hedge Funds styles. The volatility, skewness and kurtosis implied in the US options markets are used by Hedge Fund managers as instruments to anticipate market movements. Managers should adjust their market exposure in response to variations in the implied higher moments. We show that higher-moment premia improve a conditional asset pricing model both in terms of explanatory power (R-squares and Schwarz criterion) and specification errors across all Hedge Fund styles. [less ▲]

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See detailHighest prevalence of vitamin D inadequacy in institutionalized women compared with noninstitutionalized women: a case-control study.
Bruyère, Olivier ULg; Decock, Caroline; Delhez, Melanie et al

in Women's Health (2009), 5(1), 49-54

The reduced capacity of older skin to synthesize vitamin D(3) under the influence of ultraviolet light makes older persons at risk of vitamin D deficiency. The risk could even be increased in ... [more ▼]

The reduced capacity of older skin to synthesize vitamin D(3) under the influence of ultraviolet light makes older persons at risk of vitamin D deficiency. The risk could even be increased in institutionalized persons owing to their lower sunshine exposure. It has been reported that an inadequate vitamin D level is associated with secondary hyperparathyroidism, increased bone turnover, and bone loss, which increase fracture risk. The objective of this study was to assess the prevalence of inadequate serum vitamin D levels in institutionalized, postmenopausal, osteoporotic women. Assessment of 25-hydroxyvitamin D [25(OH)D] was performed in 445 institutionalized, osteoporotic women from nine countries (Australia, Belgium, France, Germany, Hungary, Italy, Poland, Spain and UK). For each institutionalized woman, three age-matched, noninstitutionalized, osteoporotic controls were also included. Four cutoffs of 25(OH)D inadequacy were fixed: less than 80, less than 75, less than 50 and less than 30 nmol/l. Mean age was 79.7 years (standard deviation [SD] = 5.8) for the institutionalized women and 79.5 years (SD = 5.5) for the noninstitutionalized women (p = 0.45). Significantly fewer institutionalized women received vitamin D supplements (13.2 vs 24.0%; p < 0.0001). In women without vitamin D supplements, the level of 25(OH)D was significantly lower in institutionalized women (56.9 [SD = 23.9] nmol/l) compared with noninstitutionalized women (63.2 [SD = 22.0] nmol/l; p < 0.0001). In institutionalized women (without vitamin D supplements), the prevalence of 25(OH)D inadequacy was 10.4, 41.2, 80.3 and 84.2% when considering cutoffs of 80, 75, 50 and 30 nmol/l, respectively. In the control group, the prevalence was 2.7, 22.9, 74.4 and 81.7%, respectively. The prevalence of vitamin D inadequacy was significantly higher in institutionalized women when considering the 75, 50 and 30 nmol/l cutoffs but not when considering the 80 nmol/l cutoff. This study highlights a high prevalence of vitamin D inadequacy in institutionalized, osteoporotic women. Compared with age-matched osteoporotic controls, the prevalence of severe vitamin D inadequacy was substantially more important in institutionalized women. We believe that a greater awareness of the importance of vitamin D inadequacy is needed in order to address this public health problem. [less ▲]

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See detailHighlighting the immunohistochemical profile of melanocytomas: review.
Quatresooz, Pascale ULg; Pierard, Claudine ULg; Pierard, Gérald ULg

in Oncology Reports (2008), 19(6), 1367-72

The histological assessment of atypical melanocytic neoplasms is mandatory to ensure proper diagnosis and treatment. However, for some atypical lesions, expert pathologists report only moderate ... [more ▼]

The histological assessment of atypical melanocytic neoplasms is mandatory to ensure proper diagnosis and treatment. However, for some atypical lesions, expert pathologists report only moderate concordance in the diagnosis. In addition, certain atypical neoplasms have been coined differently in the literature. These designations include among others atypical and metastasizing Spitz tumor, malignant Spitz naevus, borderline and intermediate melanocytic tumor, and melanocytic tumor of uncertain malignant potential (MELTUMP) or Spitzoid melanocytic tumor of uncertain malignant potential (STUMP). These neoplasms are grouped here under the heading melanocytoma. Such melanocytic lesions have a benign outcome but exhibit an atypical and worrisome aspect. Rare individual cases of melanocytomas can progress to locoregional disease (agminate melanocytomas), and even beyond. At times, the distinction between melanocytoma and melanoma is difficult and may even be impossible. However, multipronged immunohistochemistry can help define malignancy risk stratification and therapeutic guidelines. [less ▲]

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See detailHighlighting the rim of the perifollicular epidermal unit.
Xhauflaire, Emmanuelle ULg; Hermanns, Jean-Francois; Pierard, Claudine ULg et al

in European Journal of Dermatology (2006), 16(3), 225-9

The perifollicular and interfollicular areas of normal skin may look similar. However, some physiological and pathological processes may specifically involve a thin perifollicular rim. This review ... [more ▼]

The perifollicular and interfollicular areas of normal skin may look similar. However, some physiological and pathological processes may specifically involve a thin perifollicular rim. This review illustrates some of the methods available for highlighting the rim of the perifollicular epidermal unit. Non invasive methods rely on dermoscopy, ultraviolet light enhanced visualization (ULEV), skin capacitance imaging and cyanoacrylate skin surface strippings (CSSS). Conventional histology and immunohistochemistry may also show specific perifollicular features without, however, revealing the aspects highlighted by the specific non invasive methods. The clinically relevant modifications consist of pigmentary and hyperkeratotic perifollicular changes. [less ▲]

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See detailHighlights from the Seventh European Congress on Clinical and Economic Aspects of Osteoporosis and Osteoarthritis
Bruyère, Olivier ULg; Reginster, Jean-Yves ULg

in Expert Opinion on Pharmacotherapy (2007), 8(11), 1779-1784

The Seventh European Congress on Clinical and Economic Aspects of Osteoporosis and Osteoarthritis (ECCEO), which was held in Porto between March 28 and March 30, 2007, was the largest meeting in Europe in ... [more ▼]

The Seventh European Congress on Clinical and Economic Aspects of Osteoporosis and Osteoarthritis (ECCEO), which was held in Porto between March 28 and March 30, 2007, was the largest meeting in Europe in the field of osteoporosis and osteoarthritis. The meeting was attended by similar to 4000 scientists and health professionals seeking information on the epidemiology, pathogenesis, prevention and treatment of osteoporosis and osteoarthritis. Specifically addressing these topics, > 500 abstracts were submitted. This paper highlights and summarises the important findings of ECCEO 2007. [less ▲]

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See detailHighlights of the 2007 scientific sessions of the European Society of Cardiology Vienna, Austria, September 1-5, 2007.
Kristensen, Steen D.; Baumgartner, Helmut; Drexler, Helmut et al

in Journal of the American College of Cardiology (2007), 50(25), 2421-30

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See detailHighlights of the 2008 Scientific Sessions of the European Society of Cardiology Munich, Germany, August 30 to September 3, 2008.
Kristensen, Steen D; Baumgartner, Helmut; Casadei, Barbara et al

in Journal of the American College of Cardiology (2008), 52(24), 2032-42

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See detailHighlights of the annual congress of the European Association of Nuclear Medicine, Copenhagen 2007.
Knuuti, Juhani; Hustinx, Roland ULg

in European Journal of Nuclear Medicine and Molecular Imaging (2008), 35(3), 655-72

INTRODUCTION: The Annual Congress of the European Association of Nuclear Medicine took place in Copenhagen on October 13-17, 2007. The event is the major scientific and professional effort in the field of ... [more ▼]

INTRODUCTION: The Annual Congress of the European Association of Nuclear Medicine took place in Copenhagen on October 13-17, 2007. The event is the major scientific and professional effort in the field of nuclear medicine in Europe. The most important developments in the fields of instrumentation, radionuclide production, radiochemistry, radiotherapy, as well as the clinical imaging fields of neurology, cardiology, oncology, and general sciences were reported. OBJECTIVE: This paper emphasizes the major findings and trends at this important gathering. This review is, however, only a brief summary of the large amount of data discussed. [less ▲]

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See detailHighly Confined Spin-Polarized Two-Dimensional Electron Gas in SrTiO3/SrRuO3 Superlattices
Verissimo-Alves, M.; Garcia-Fernandez, P.; Bilc, Daniel ULg et al

in Physical Review Letters (2012), 108

We report first-principles characterization of the structural and electronic properties of (SrTiO3)5/(SrRuO3)1 superlattices. We show that the system exhibits a spin-polarized two-dimensional electron gas ... [more ▼]

We report first-principles characterization of the structural and electronic properties of (SrTiO3)5/(SrRuO3)1 superlattices. We show that the system exhibits a spin-polarized two-dimensional electron gas, extremely confined to the 4d orbitals of Ru in the SrRuO3 layer. Every interface in the superlattice behaves as a minority-spin half-metal ferromagnet, with a magnetic moment of µ = 2.0µB/SrRuO3 unit. The shape of the electronic density of states, half-metallicity, and magnetism are explained in terms of a simplified tight-binding model, considering only the t2g orbitals plus (i) the bidimensionality of the system and (ii) strong electron correlations. [less ▲]

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See detailHighly dispersed iron xerogel catalysts for p-nitrophenol degradation by photo-Fenton effects
Mahy, Julien ULg; Tasseroul, Ludivine ULg; Zubiaur, Anthony ULg et al

in Microporous & Mesoporous Materials (2014), 197

Several iron xerogel catalysts were synthesized by hydrolysis and condensation of tetraethoxysilane (TEOS) and 3-(2-aminoethylamino)propyltrimethoxysilane (EDAS) which is able to form a chelate with iron ... [more ▼]

Several iron xerogel catalysts were synthesized by hydrolysis and condensation of tetraethoxysilane (TEOS) and 3-(2-aminoethylamino)propyltrimethoxysilane (EDAS) which is able to form a chelate with iron ions. The EDAS/TEOS ratio strongly influences the texture of xerogel catalysts. The specific surface area and the micro- and mesoporous volume increase with this ratio. It seems that EDAS plays a nucleating agent role for silica particles and allows to anchor Fe-based moieties inside the silica network. Iron oxide nanoparticles of diameter 1-1.5 nm and Fe3+ ions result, encapsulated in silica particles with sizes of about 10-30 nm in diameter. The iron species was determined by Mössbauer spectroscopy and magnetometry measurements and only Fe3+ species were observed in xerogel catalysts. The Fenton and photo-Fenton effect of these catalysts were evaluated on the degradation of p-nitrophenol in aqueous media under different conditions. Results show that in the presence of H2O2, iron xerogel catalysts present a photo-Fenton effect, reaching 99 % of degradation after 24 h. [less ▲]

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See detailHighly dispersed iron xerogel catalysts for p-nitrophenol degradation by photo-Fenton effects
Mahy, Julien ULg; Tasseroul, Ludivine ULg; Zubiaur, Anthony ULg et al

Poster (2014, July)

Since the beginning of the industrial era, the various human activities have increased steadily, leading to a rapid technological development and a high population growth. Thus, the expansion of the ... [more ▼]

Since the beginning of the industrial era, the various human activities have increased steadily, leading to a rapid technological development and a high population growth. Thus, the expansion of the industry has heavily polluted the atmosphere, soil and water with negative consequences for humans and environment [1]. To decrease this pollution, it exists various treatment methods: chemical, physical and biological [2,3]. Among all these methods, a recent way of treatment is the degradation of pollutants in soils or waters by Fenton and photo-Fenton reactions [3] which use H2O2, iron-based compounds and UV light. In this way, several Fe2O3/SiO2 xerogel catalysts were synthesized by cogelation method by hydrolysis and condensation of tetraethoxysilane (TEOS) and 3-(2-aminoethylamino)propyltrimethoxysilane (EDAS) which is able to form a chelate with iron ions [4]. Five samples were synthesized: four samples with different percentage of iron (0.5, 1, 1.5 and 2.5 theoretical wt% confirmed by ICP-AES measurements), and a sample of pure silica. TEM pictures, nitrogen adsorption-desorption and mercury porosimetry measurements have established that EDAS plays a role of nucleating agent of silica particles [5,6] and allows to anchor iron particles inside silica network [4]. Indeed, it results iron nanoparticles of diameter 1-1.5 nm encapsulated in silica particles with sizes of about 10-30 nm in diameter. The species of iron was determined by Mössbauer spectroscopy and only Fe3+ ions were observed in xerogel catalysts. Then, the Fenton and photo-Fenton effect of these catalysts were evaluated on the degradation of p-nitrophenol (PNP) in aqueous medium in different conditions. Results show that Fe2O3/SiO2 xerogels present a photo-Fenton effect with H2O2, reaching with a sample 99 % of degradation after 24 h. [1] M. A. Khan, A. M. Ghouri, Environmental pollution: its effects on life and its remedies, Journal of Arts, Science & Commerce (Vol. 2), 2011, pg 276-285. [2] M. S. Kuyukina , I. B. Ivshina, Biology of rhodococcus: chapter 9, Springer, 2010, pg 232-256. [3] J. J. Pignatello, E. Oliveros, A. MacKay, Advanced Oxidation Processes for Organic Contaminant Destruction Based on the Fenton Reaction and Related Chemistry, Critical Reviews in Environmental Science and Technology (Vol. 36), 2006, pg 1-84. [4] B. Heinrichs, L. Rebbouh, J.W. Geus, S. Lambert, H.C.L. Abbenhuis, F. Grandjean, G.J. Long, J.-P. Pirard, R.A. van Santen, Iron (III) species dispersed in porous silica through sol-gel chemistry, Journal of Non-Crystalline Solids (Vol. 354), 2008, pg 665-672. [5] S. Lambert, C. Alié, J.-P. Pirard, B. Heinrichs, Study of textural properties and nucleation phenomenon in Pd/SiO2 , Ag/SiO2 and Cu/SiO2 cogelled xerogel catalysts, Journal of Non-Crystalline Solids (Vol. 342), 2004, pg 70-81. [6] B. Heinrichs, S. Lambert , N. Job , J.-P. Pirard, in "Catalyst Preparation: Science and Engineering, J. R. Regalbuto (Ed.)", CRC Press, Taylor & Francis Group, Boca Raton, 2007, p. 163-208. [less ▲]

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See detailHighly dispersed platinum catalysts prepared by impregnation of texture-tailored carbon xerogels
Job, Nathalie ULg; Ribeiro Pereira, Manuel Fernando; Lambert, Stéphanie ULg et al

in Journal of Catalysis (2006), 240(2), 160-171

Pt/C catalysts were prepared by impregnation of carbon xerogels with H2PtCl6 aqueous solutions. Three supports with various pore textures were used: two micro-mesoporous (maximum pore size = 10 and 40 nm ... [more ▼]

Pt/C catalysts were prepared by impregnation of carbon xerogels with H2PtCl6 aqueous solutions. Three supports with various pore textures were used: two micro-mesoporous (maximum pore size = 10 and 40 nm, respectively) and one micro-macroporous (maximum pore size = 70 nm). After impregnation, drying and reduction, the metal particles were at most 1-1.5 nm in diameter. The Pt dispersion was close to 100% in the case of the xerogel with large mesopores. For the two other supports, a small fraction of Pt was trapped in blocked micropores. The specific catalytic activity obtained for benzene hydrogenation was 4-10 times higher than that obtained with active charcoal-supported catalysts prepared by a similar method. The high dispersion of Pt was attributed to the presence in the xerogel of large mesopore or macropore volumes, which facilitates impregnation, and a low amount of oxygenated surface groups. (c) 2006 Elsevier Inc. All rights reserved. [less ▲]

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See detailHighly dispersed Pt/C catalysts prepared by the Charge Enhanced DryImpregnation method
Cao Chongjiang; Yang Guang; Dubau Laetitia et al

in Applied Catalysis B : Environmental (2014), 150-151

tAn efficient method to synthesize highly dispersed Pt/carbon xerogel catalysts for Proton ExchangeMembrane fuel cell applications is described. The synthesis proceeds via the Charge Enhanced ... [more ▼]

tAn efficient method to synthesize highly dispersed Pt/carbon xerogel catalysts for Proton ExchangeMembrane fuel cell applications is described. The synthesis proceeds via the Charge Enhanced DryImpregnation method (CEDI), which combines dry impregnation with the Strong Electrostatic Adsorp-tion technique (SEA). The samples prepared via CEDI or SEA techniques were dried and reduced underhydrogen to obtain supported Pt nanoparticles. In order to increase the Pt mass fraction up to 10 wt.%,two successive impregnation-drying-reduction cycles were performed. The synthesized Pt nanoparticlesare homogeneously distributed on the carbon support and highly dispersed (mean Pt nanoparticle sizeof ca. 2 nm). The CEDI method is ideally suited to avoid Pt losses during the catalyst preparation. [less ▲]

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See detailHighly effective SNP-based association mapping and management of recessive defects in livestock.
Charlier, Carole ULg; Coppieters, Wouter ULg; Rollin, Frédéric ULg et al

in Nature Genetics (2008), 40(4), 449-54

The widespread use of elite sires by means of artificial insemination in livestock breeding leads to the frequent emergence of recessive genetic defects, which cause significant economic and animal ... [more ▼]

The widespread use of elite sires by means of artificial insemination in livestock breeding leads to the frequent emergence of recessive genetic defects, which cause significant economic and animal welfare concerns. Here we show that the availability of genome-wide, high-density SNP panels, combined with the typical structure of livestock populations, markedly accelerates the positional identification of genes and mutations that cause inherited defects. We report the fine-scale mapping of five recessive disorders in cattle and the molecular basis for three of these: congenital muscular dystony (CMD) types 1 and 2 in Belgian Blue cattle and ichthyosis fetalis in Italian Chianina cattle. Identification of these causative mutations has an immediate translation into breeding practice, allowing marker assisted selection against the defects through avoidance of at-risk matings. [less ▲]

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See detailHighly efficient cobalt-mediated radical polymerization of vinyl acetate
Debuigne, Antoine ULg; Caille, Jean-Raphaël; Jérôme, Robert ULg

in Angewandte Chemie (International ed. in English) (2005), 44(7), 1101-1104

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See detailHighly efficient organic/inorganic titania xerogels for photocatalysis applications
Bodson, Céline ULg; Bied, Catherine; Páez Martínez, Carlos ULg et al

Poster (2011)

TiO2 heterogeneous photocatalysis is an attractive technique for the complete destruction of undesirable contaminants either in aqueous or gaseous phase by using solar or artificial light illumination ... [more ▼]

TiO2 heterogeneous photocatalysis is an attractive technique for the complete destruction of undesirable contaminants either in aqueous or gaseous phase by using solar or artificial light illumination. The main drawback of TiO2 is that it can be activated only by UV light because of its large band gap (3.20 eV for anatase). Thus, it would be interesting to sensitize TiO2 to the whole visible region by doping with non-metal atoms such as phosphorus. Furthermore, it was found that the P-doped species could significantly increase the specific surface area of the materials, which consequently exhibit a higher content of surface hydroxyl groups. Upon band gap excitation of TiO2, the photoinduced electrons and positively charged holes can reduce and oxidize the species adsorbed on the TiO2 particles. The high degree of recombination between photogenerated electrons and holes is a major rate-limiting factor controlling the photocatalytic efficiency. Attempts to increase the titania efficiency have been made by doping P-doped TiO2 with metals, such as Ag. In the present study, a sol-gel method is developed to synthesize P-doped TiO2 and P/Ag-codoped xerogels by a cogelation method [1] based on the hydrolysis and the condensation of Ti(OC3H7)4 in the presence of a phosphoryled compound able to complex silver: NH2-(CH2)2-NH-(CH2)2-P(O)-(OC2H5)2, EDAP), in various alcohols. These xerogels are dried at 150°C under vacuum for 24 h, and calcined under air for 5 h at 350°C, 450°C, 550°C and 650°C. The resulting materials were characterized by ICP-AES, TG-DSC, TEM, XRD, nitrogen adsorption-desorption isotherms, FT-IR and diffuse reflectance measurements in the UV/Vis region. To measure the photoactivity of these new hybrid organic/inorganic titania xerogels, all these samples were tested for the degradation of p-nitrophenol under visible light. The titanium, phosphorus and silver contents in xerogels were confirmed by ICP-AES. As expected, theoretical and actual Ti/P molar ratio and Ag contents in xerogels are similar and then after washing with THF for 48 h. These results allow to conclude that EDAP and Ag are well incorporated within the TiO2 matrix: EDAP is anchored in the titania matrix by complexation and cogelation with TTIP [2], whereas silver, first incorporated by complexation through the ethylenediamine fragment of EDAP, is present in the xerogels in the form of nanoparticles. It was found that the phosphor-doped species could significantly increase the surface area of the materials. [2] It is noteworthy that the porosity of these materials is not affected by the addition of silver acetate during the synthesis, a very slight decrease of the specific surface area being observed in all cases. The organic/inorganic hybrid titania materials display very high photocatalytic efficiencies in the degradation of p-nitrophenol compared to pure titania. Deeper investigations concerning the structure of these materials should enable a better understanding of the photocatalytic mechanisms involved with these hybrids and will soon be reported. 1. S. Lambert, K. Y. Tran, G. Arrachart, F. Noville, C. Henrist, C. Bied, J. J. E. Moreau, M. Wong Chi Man, B. Heinrichs, Micropor. Mesopor. Mater. 2008, 115, 609. 2. C.J.Bodson1, S.D. Lambert1, C. Alié1, X. Cattoën2, J-P. Pirard1, C. Bied2, M.Wong Chi Man2, B. Heinrichs1 ,Micropor. Mesopor. Mater. 2010, 134,157 [less ▲]

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See detailHighly Efficient Separation of Actinide from Lanthanide by a Phenanthroline-Derived Bis-triazine Ligand
Lewis, Frank W.; Harwood, Laurence M.; Hudson, Michael J. et al

in Journal of the American Chemical Society (2011), 133

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See detailHighly enantioselective synthesis of no-carrier-added 6-[18F]Fluoro-L-dopa by chiral phase-transfer alkylation
Lemaire, Christian ULg; Gillet, Steve; Guillouet, Stéphane et al

in European Journal of Organic Chemistry (2004), (13), 2899-2904

[F-18]Fluoro-L-dopa, an important radiopharmaceutical for positron emission tomography (PET), has been synthesized using a phase-transfer alkylation reaction. A chiral quaternary ammonium salt derived ... [more ▼]

[F-18]Fluoro-L-dopa, an important radiopharmaceutical for positron emission tomography (PET), has been synthesized using a phase-transfer alkylation reaction. A chiral quaternary ammonium salt derived from a Cinchona alkaloid served as phase-transfer catalyst for the enantioselective alkylation of a glycine derivative. The active methylene group of this Schiff-base substrate was deprotonated with cesium hydroxide and rapidly alkylated by the 2-[F-18]fluoro-4,5-dimethoxybenzyl halide (X = Br, I). The reaction proceeded with high yield (> 90%) at 0 degreesC or room temperature in various solvents such as toluene or dichloromethane. Preparation of the [F-18]alkylating agent on a solid support was developed. After labelling, the labeled [F-18]fluoroveratraldehyde was trapped on a (t)C18 cartridge and then converted on the cartridge into the corresponding benzyl halide derivatives by addition of aqueous sodium borohydride and gaseous hydrobromic or -iodic acid. Hydrolysis and purification by preparative HPLC made 6-[F-18]fluoro-L-dopa ready for human injection in a 25-30% decay-corrected radiochemical yield in a synthesis time of 100 min. The product was found to be chemically, radiochemically and enantiomerically pure (ee > 95%). (C) Wiley-VCH Verlag GmbH [less ▲]

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