References of "Nguyen, Bach Kim"
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See detailBelgian beekeeping situation and the symptomatology as discriminatory tools
Nguyen, Bach Kim ULg; Mignon, Jacques ULg; Haubruge, Eric ULg

in Proceedings of the 4th Coloss Conference - Prevention of honey bee losses. COLOSS. Zagreb 3-4 March. abstract book p.8 (2009)

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See detailColony collapse disorder: a descriptive study.
Vanengelsdorp, Dennis; Evans, Jay D; Saegerman, Claude ULg et al

in PLoS ONE (2009), 4(8), 6481

BACKGROUND: Over the last two winters, there have been large-scale, unexplained losses of managed honey bee (Apis mellifera L.) colonies in the United States. In the absence of a known cause, this ... [more ▼]

BACKGROUND: Over the last two winters, there have been large-scale, unexplained losses of managed honey bee (Apis mellifera L.) colonies in the United States. In the absence of a known cause, this syndrome was named Colony Collapse Disorder (CCD) because the main trait was a rapid loss of adult worker bees. We initiated a descriptive epizootiological study in order to better characterize CCD and compare risk factor exposure between populations afflicted by and not afflicted by CCD. METHODS AND PRINCIPAL FINDINGS: Of 61 quantified variables (including adult bee physiology, pathogen loads, and pesticide levels), no single measure emerged as a most-likely cause of CCD. Bees in CCD colonies had higher pathogen loads and were co-infected with a greater number of pathogens than control populations, suggesting either an increased exposure to pathogens or a reduced resistance of bees toward pathogens. Levels of the synthetic acaricide coumaphos (used by beekeepers to control the parasitic mite Varroa destructor) were higher in control colonies than CCD-affected colonies. CONCLUSIONS/SIGNIFICANCE: This is the first comprehensive survey of CCD-affected bee populations that suggests CCD involves an interaction between pathogens and other stress factors. We present evidence that this condition is contagious or the result of exposure to a common risk factor. Potentially important areas for future hypothesis-driven research, including the possible legacy effect of mite parasitism and the role of honey bee resistance to pesticides, are highlighted. [less ▲]

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See detailMortalités, effondrements et affaiblissements des colonies d'abeilles
Toma, Bernard; Alix, Anne; Carpentier, P. et al

Report (2009)

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See detailLe dépérissement des abeilles
Nguyen, Bach Kim ULg; Haubruge, Eric ULg

Conference given outside the academic context (2009)

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See detailDoes Imidacloprid Seed-Treated Maize Have an Impact on Honey Bee Mortality?
Nguyen, Bach Kim ULg; Saegerman, Claude ULg; Pirard, Catherine et al

in Journal of Economic Entomology (2009), 102(2), 616-623

Beekeepers suspected maize. Zea mays L., treated with imidacloprid to result in substantial loss of honey bee (Hymenoptera: Apidae) colonies in Belgium. The objective of this study was to investigate the ... [more ▼]

Beekeepers suspected maize. Zea mays L., treated with imidacloprid to result in substantial loss of honey bee (Hymenoptera: Apidae) colonies in Belgium. The objective of this study was to investigate the potential impact of maize grown from imidacloprid-treated seeds on honey bee mortality. A survey of 16 apiaries was carried out, and all maize fields treated or not with imidacloprid were located within a radius of 3,000 m around the observed apiaries. Samples of honey, beeswax, and bees were collected in three colonies per apiary and analyzed for pesticide contain by liquid chromatography-tandem mass spectrometry and gas chromatography-tandem mass spectrometry. We first found significant correlation between the number of colonies per apiary and the mortality rates in an apiary. In addition, this mortality rate was inversely correlated with the surface of maize fields treated and not with imidacloprid, suggesting that this pesticide do not interact with bees fitness. Moreover, a very large number of our samples contained acarcides either prohibited or ineffective against varroa destructor (Anderson & Trueman) (Acari: Varroidae), suggesting that the treatment method used by the beekeepers to be inadequate for mite control. Our results support the hypothesis that imidacloprid seed-treated maize has no negative impact on honey bees. [less ▲]

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See detailPresence of six bee viruses in Apis mellifera L. populations in Wallonia (Belgium)
Mignon, Jacques ULg; Snoeck, Chantal; Nguyen, Bach Kim ULg et al

Poster (2008)

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See detailDoes one observe the honeybee colony collapse disorder in Europe ?
Nguyen, Bach Kim ULg; Haubruge, Eric ULg

Conference given outside the academic context (2007)

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See detailEtat sanitaire des ruchers en Région wallonne (Belgique)
Mignon, Jacques ULg; Nguyen, Bach Kim ULg; Snoeck, C. et al

Poster (2007, November)

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See detailDevelopment and validation of a multi-residue method for pesticide determination in honey using on-column liquid-liquid extraction and liquid chromatography-tandem mass spectrometry
Pirard, Catherine; Widart, Joëlle ULg; Nguyen, Bach Kim ULg et al

in Journal of Chromatography. A (2007), 1152(1-2), 116-123

We report on the development and validation under ISO 17025 criteria of a multi-residue confirmatory method to identify and quantify 17 widely chemically different pesticides (insecticides: Carbofuran ... [more ▼]

We report on the development and validation under ISO 17025 criteria of a multi-residue confirmatory method to identify and quantify 17 widely chemically different pesticides (insecticides: Carbofuran, Methiocarb, Pirimicarb, Dimethoate, Fipronil, Imidacloprid; herbicides: Amidosulfuron, Rimsulfuron, Atrazine, Simazine, Chloroturon, Linuron, Isoxaflutole, Metosulam; fungicides: Diethofencarb) and 2 metabolites (Methiocarb sulfoxide and 2-Hydroxytertbutylazine) in honey. This method is based on an on-column liquid liquid extraction (OCLLE) using diatomaceous earth as inert solid support and liquid chromatography (LC) coupled to mass spectrometry (MS) operating in tandem mode (MS/MS). Method specificity is ensured by checking retention time and theoretical ratio between two transitions from a single precursor ion. Linearity is demonstrated all along the range of concentration that was investigated, from 0.1 to 20 ng g(-1) raw honey, with correlation coefficients ranging from 0.921 to 0.999, depending on chemicals. Recovery rates obtained on home-made quality control samples are between 71 and 90%, well above the range defined by the EC/657/2002 document, but in the range we had fixed to ensure proper quantification, as levels found in real samples could not be corrected for recovery rates. Reproducibility is found to be between 8 and 27%. Calculated CC alpha and CC beta (0.0002-0.943 mg g(-1) for CC alpha, and 0.0002-1.232 ng g(-1) for CCP) show the good sensitivity attained by this rnulti-residue analytical method. The robustness of the method has been tested in analyzing more than 100 raw honey samples collected from different areas in Belgium, as well as some wax and bee samples, with a slightly adapted procedure. (C) 2007 Elsevier B.V. All rights reserved. [less ▲]

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See detailVirale bijenziekten
Nguyen, Bach Kim ULg; Haubruge, Eric ULg

Conference given outside the academic context (2007)

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See detailLa varroase et les maladies liées au rucher
Nguyen, Bach Kim ULg; Haubruge, Eric ULg

Conference given outside the academic context (2007)

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See detailDépérissement de nos abeilles?
Nguyen, Bach Kim ULg; Widart, Joëlle ULg; De Pauw, Edwin ULg et al

Article for general public (2007)

Detailed reference viewed: 48 (14 ULg)