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See detailFirst detection of CTX-M-28 in a Tunisian hospital from a cefotaxime-resistant Klebsiella pneumoniae strain.
Ben Achour, N.; Mercuri, Paola ULg; Power, P. et al

in Pathologie-biologie (2009), 57(5), 343-8

A cefotaxime-resistant Klebsiella pneumoniae ML4313 was obtained from a patient from intensive care unit of Military hospital in Tunisia. This strain was resistant to beta-lactams, aminoglycosides ... [more ▼]

A cefotaxime-resistant Klebsiella pneumoniae ML4313 was obtained from a patient from intensive care unit of Military hospital in Tunisia. This strain was resistant to beta-lactams, aminoglycosides, quinolones and phenicols, and tetracyclines. It was identified as producer of extended-spectrum beta-lactamases (ESBL) by double-disk synergy test between amoxicillin-clavulanate and cefotaxime, ceftriaxone, ceftazidime and aztreonam. The ESBL was identified as CTX-M-28 by sequencing of PCR products and by isoelectric focusing. The ESBL resistance was transferred by a 50kb plasmid. CTX-M-28 is closely related to CTX-M-15. This is the first description of this enzyme in Tunisia. [less ▲]

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See detailFirst detection of hydroxyl in the atmosphere of Venus
Piccioni, G.; Drossart, P.; Zasova, L. et al

in Astronomy and Astrophysics (2008), 483

Context: Airglow emissions, such as previously observed from NO and O2(a-X) (0-0) on Venus, provide insight into the chemical and dynamical processes that control the composition and energy balance in the ... [more ▼]

Context: Airglow emissions, such as previously observed from NO and O2(a-X) (0-0) on Venus, provide insight into the chemical and dynamical processes that control the composition and energy balance in the upper atmospheres of planets. The OH airglow emission has been observed previously only in the Earth's atmosphere where it has been used to infer atomic oxygen abundances. The O2(a-X) (0-1) airglow emission also has only been observed in the Earth's atmosphere, and neither laboratory nor theoretical studies have reached a consensus on its transition probability. Aims: We report measurements of night-side airglow emission in the atmosphere of Venus in the OH (2-0), OH (1-0), O2(a-X) (0-1), and O2(a-X) (0-0) bands. This is the first detection of the first three of these airglow emissions on another planet. These observations provide the most direct observational constraints to date on H, OH, and O3, key species in the chemistry of Venus' upper atmosphere. Methods: Airglow emission detected at wavelengths of 1.40-1.49 and 2.6-3.14 mum in limb observations by the Visible and Infrared Thermal Imaging Spectrometer (VIRTIS) on the Venus Express spacecraft is attributed to the OH (2-0) and (1-0) transitions, respectively, and compared to calculations from a photochemical model. Simultaneous limb observations of airglow emission in the O2(a-X) (0-0) and (0-1) bands at 1.27 and 1.58 mum, respectively, were used to derive the ratio of the transition probabilities for these bands. Results: The integrated emission rates for the OH (2-0) and (1-0) bands were measured to be 100 ± 40 and 880±90 kR respectively, both peaking at an altitude of 96 ± 2 km near midnight local time for the considered orbit. The measured ratio of the O2(a-X) (0-0) and (0-1) bands is 78 ± 8. Conclusions: Photochemical model calculations suggest the observed OH emission is produced primarily via the Bates-Nicolet mechanism, as on the Earth. The observed ratio of the intensities of the O2(a-X) (0-0) and (0-1) bands implies the ratio of their transition probabilities is 63±6. [less ▲]

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See detailFirst detection of phase-dependent colliding wind X-ray emission outside the Milky Way
Nazé, Yaël ULg; Corcoran, M. F.; Koenigsberger, G. et al

in Astrophysical Journal (2007), 658(1, Part 2), 25-28

After having reported the detection of X-rays emitted by the peculiar system HD 5980, we assess here the origin of this high-energy emission from additional X-ray observations obtained with XMM-Newton ... [more ▼]

After having reported the detection of X-rays emitted by the peculiar system HD 5980, we assess here the origin of this high-energy emission from additional X-ray observations obtained with XMM-Newton. This research provides the first detection of apparently periodic X-ray emission from hot gas produced by the collision of winds in an evolved massive binary outside the Milky Way. It also provides the first X-ray monitoring of a luminous blue variable only years after its eruption and shows that the dominant source of the X-rays is not associated with the ejecta. After having reported the detection of X-rays emitted by the peculiar system HD 5980, we assess here the origin of this high-energy emission from additional X-ray observations obtained with XMM-Newton. This research provides the first detection of apparently periodic X-ray emission from hot gas produced by the collision of winds in an evolved massive binary outside the Milky Way. It also provides the first X-ray monitoring of a luminous blue variable only years after its eruption and shows that the dominant source of the X-rays is not associated with the ejecta. [less ▲]

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See detailFirst detection of resistance to QOI fungicides in Mycosphaerella graminicola on winter wheat in Belgium
Amand, O.; Calay, F.; Coquillart, L. et al

in Communications in Agricultural and Applied Biological Sciences (2003, May 06), 68(4b), 519-531

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See detailFirst Direct Assay for Intact Human Proinsulin
Houssa, P.; Dinesen, B.; Deberg, Michelle ULg et al

in Clinical Chemistry (1998), 44(7), 1514-9

We describe a sensitive two-site sandwich enzyme-linked immunosorbent assay for the measurement of intact human proinsulin in 100 microL of serum or plasma. The assay is based on the use of two monoclonal ... [more ▼]

We describe a sensitive two-site sandwich enzyme-linked immunosorbent assay for the measurement of intact human proinsulin in 100 microL of serum or plasma. The assay is based on the use of two monoclonal antibodies specific for epitopes at the C-peptide/insulin A chain junction and at the insulin B chain/C-peptide junction, respectively. Cross-reactivities with insulin, C-peptide, and the four proinsulin conversion intermediates were negligible. The detection limit in buffer was 0.2 pmol/L (3 standard deviations from zero). The working range was 0.2-100 pmol/L. The mean intra- and interassay coefficients of variation were 2.4% and 8.9%, respectively. The mean recovery of added proinsulin was 103%. Dilution curves of 40 serum samples are parallel to the proinsulin calibration curve. Proinsulin concentrations in 20 fasting healthy subjects were all above the limit of detection: median (range), 2.7 pmol/L (1.1-6.9 pmol/L). Six fasting non-insulin-dependent diabetes mellitus and five insulinoma patients had proinsulin concentrations significantly higher than healthy subjects: median (range), 7.7 pmol/L (3.2-18 pmol/L) and 153 pmol/L (98-320 pmol/L), respectively. [less ▲]

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See detailFirst do not harm
Jamoulle, Marc ULg

in Journal of Mid-life Health (2015), 6(2), 51-52

commentary on Kalra B, Malik S. Quaternary prevention and menopause. J Midlife Health 2014;5:53-4.

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See detailFirst epidemiological data on pathogenic leptospires isolated on the Azorean islands
Collares-Pereira, Margarida; Korver, H.; Terpstra, W. J. et al

in European Journal of Epidemiology (1997), 13

Insectivores (Erinaceus europaeus) and rodents (Rattus rattus, R. norvegicus and Mus musculus) from different islands of the Azores archipelago were found to carry three distinct Leptospira interrogans s ... [more ▼]

Insectivores (Erinaceus europaeus) and rodents (Rattus rattus, R. norvegicus and Mus musculus) from different islands of the Azores archipelago were found to carry three distinct Leptospira interrogans s.l. serovars (copenhageni, icterohaemorrhagiae and ballum) which have never been previously investigated there. The house mouse and the black rat were the major Leptospira reservoir showing isolation rates ranging from 0% for both species (in Graciosa) to 88 % and 33 %, respectively (in São Miguel). This study also showed that the majority of the animals with positive kidney cultures exhibited specific agglutinins agaibst the isolated strains of Leptospira. The observed isalation rates in the different islands, with a very interesting island variation in prevalence, suggest that small mammals, serving as sylvatic reservoirs of pathogenic leptospires, may represent an important risk to the health of humans and the livestock, particularly in the islands of Terceira and São Miguel. [less ▲]

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See detailFirst epidemiological study on exposure to Neospora caninum in different canine populations in the Algiers District (Algeria)
Ghalmi, F.; China, B.; Kaïdi, R. et al

in Parasitology International (2009), 58(4), 444-450

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See detailFirst estimates of the contribution of CaCO3 precipitation to the release of CO2 to the atmosphere during young sea ice growth
Geilfus, Nicolas-Xavier ULg; Carnat, Gauthier; Dieckmann, G.S. et al

in Journal of Geophysical Research. Oceans (2013), 118(1-12), 244-255

We report measurements of pH, total alkalinity, air-ice CO2 fluxes (chamber method) and CaCO3 content of frost flowers (FF) and thin landfast sea ice. As the temperature decreases, concentration of ... [more ▼]

We report measurements of pH, total alkalinity, air-ice CO2 fluxes (chamber method) and CaCO3 content of frost flowers (FF) and thin landfast sea ice. As the temperature decreases, concentration of solutes in the brine skim (BS) increases. Along this gradual concentration process, some salts reach their solubility threshold and start precipitating. The precipitation of ikaite (CaCO3.6H2O) was confirmed in the FF and throughout the ice by Raman spectroscopy and X-ray analysis. The amount of ikaite precipitated was estimated to be 25 µmol kg-1 melted FF, in the FF and is shown to decrease from 19 µmol kg-1 to 15 µmol kg-1 melted ice in the upper part and at the bottom of the ice, respectively. CO2 release due to precipitation of CaCO3 is estimated to be 50 µmol kg-1 melted samples. The dissolved inorganic carbon (DIC) normalized to a salinity of 10 exhibits significant depletion in the upper layer of the ice and in the FF. This DIC loss is estimated to be 2069 µmol kg-1 melted sample and corresponds to a CO2 release from the ice to the atmosphere ranging from 20 to 40 mmol m-2 d-1. This estimate is consistent with flux measurements of air-ice CO2 exchange. Our measurements confirm previous laboratory findings that growing young sea ice acts as a source of CO2 to the atmosphere. CaCO3 precipitation during early ice growth appears to promote the release of CO2 to the atmosphere however its contribution to the overall release by newly formed ice is most likely minor. [less ▲]

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See detailFirst evidence for a resolved structure in the inner Vega system
Absil, Olivier ULg

Poster (2005, October 01)

We report on infrared interferometric observations of Vega obtained in May and June 2005 with the FLUOR instrument installed on the CHARA interferometer. The combination of short and long baselines has ... [more ▼]

We report on infrared interferometric observations of Vega obtained in May and June 2005 with the FLUOR instrument installed on the CHARA interferometer. The combination of short and long baselines has allowed us to study the brightness distribution of the stellar photosphere, and to detect a spatial component which is over-resolved at our lowest resolution (~15 milli-arcseconds). This would be attributed to structure much larger than Vega, but within the CHARA/FLUOR field-of-view (about 1 arcsecond in radius, i.e., 8 AU around Vega). The contrast between the resolved flux and the central star is only slightly above the 1% level in K band. This emission could be interpreted as the first direct detection of thermal and/or scattered light emanating from the innermost part of the Vega debris disk, which is thought to be continuously replenished by asteroid collisions and/or comet evaporation. The possibility of a close stellar or sub-stellar companion is also investigated. [less ▲]

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See detailFirst evidence of a Lysobacter member as a biological control agent of Plasmopara viticola
Puopolo, G.; Jourdan, E.; Ongena, Marc ULg et al

in Bulletin OILB/SROP = IOBC/WPRS Bulletin (2013), 86

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See detailFirst Evidence of a Volatile Sex Pheromone in Harmonia axyridis (Pallas)
Fassotte, Bérénice ULg; Fischer, Christophe ULg; Durieux, Delphine ULg et al

Poster (2013, October)

Until now, no volatile sex pheromone has been highlighted in Coccinellidae but various studies have suggested the existence of such molecules. In the present work, we have sampled volatile organic ... [more ▼]

Until now, no volatile sex pheromone has been highlighted in Coccinellidae but various studies have suggested the existence of such molecules. In the present work, we have sampled volatile organic compounds released in the headspace of virgin females in the multicolored Asian ladybeetle, Harmonia axyridis (Pallas), that were either allowed or not to feed on pea aphids (Acyrthosiphon pisum Harris). When fed on aphids, virgin females showed a stereotypical “calling behavior”, commonly associated with the emission of a sex pheromone in several Coleoptera species. Behavioral assays conducted with calling females in a four-arm olfactometer demonstrated that the blend of released volatile compounds was attractive at a distance for males, but not for other females. The headspace of virgin females that were not previously fed with aphids was not attractive for either sex. GC-MS analyses revealed the presence of five compounds in the volatile blend: (–)-β-caryophyllene, β-elemene, methyl-eugenol, α-humulene and α-bulnesene. Subsequently, we have collected and quantified the constituents from the blend over a period of 9 days after exposure to aphids. All five compounds were produced exclusively after feeding virgin females with aphids, and their quantity significantly increased during the whole period of collection. (–)-β-caryophyllene was found to be the major constituent, representing between 80 and 86 % of the total blend. All these results could promote the development of more specific and efficient management methods to manipulate the movements of this invasive ladybeetle and to reduce its negative impacts on biodiversity. [less ▲]

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See detailFirst evidence of a volatile sex pheromone in Harmonia axyridis (Pallas) (Coleoptera: Coccinellidae)
Fassotte, Bérénice ULg; Fischer, Christophe ULg; Durieux, Delphine ULg et al

Conference (2015, May 13)

To date, volatile sex pheromones have not been identified in the Coccinellidae family; yet, various studies have suggested that such semiochemicals exist. Here, we collected volatile chemicals released by ... [more ▼]

To date, volatile sex pheromones have not been identified in the Coccinellidae family; yet, various studies have suggested that such semiochemicals exist. Here, we collected volatile chemicals released by virgin females of the multicolored Asian lady beetle, Harmonia axyridis (Pallas), which were either allowed or not allowed to feed on aphids. Virgin females in the presence of aphids, exhibited “calling behavior”, which is commonly associated with the emission of a sex pheromone in several Coleoptera species. These calling females were found to release a blend of volatile compounds that is involved in the remote attraction (i.e., from a distance) of males. Gas Chromatography Mass Spectrometry (GC-MS) analyses revealed that (–)-β-caryophyllene was the major constituent of the volatile blend (ranging from 80 to 86%), with four other chemical components also being present; β-elemene, methyl-eugenol, α-humulene, and α-bulnesene. In a second set of experiments, the emission of the five constituents identified from the blend was quantified daily over a 9-day period after exposure to aphids. We found that the quantity of all five chemicals significantly increased across the experimental period. Finally, we evaluated the activity of a synthetic blend of these chemicals by performing bioassays which demonstrated the same attractive effect in males only. The results confirm that female H. axyridis produce a volatile sex pheromone. These findings have potential in the development of more specific and efficient biological pest-control management methods aimed at manipulating the behavior of this invasive lady beetle. [less ▲]

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See detailFirst Evidence of a Volatile Sex Pheromone in Lady Beetles
Fassotte, Bérénice ULg; Fischer, Christophe ULg; Durieux, Delphine ULg et al

in PLoS ONE (2014)

To date, volatile sex pheromones have not been identified in the Coccinellidae family; yet, various studies have suggested that such semiochemicals exist. Here, we collected volatile chemicals released by ... [more ▼]

To date, volatile sex pheromones have not been identified in the Coccinellidae family; yet, various studies have suggested that such semiochemicals exist. Here, we collected volatile chemicals released by virgin females of the multicolored Asian lady beetle, Harmonia axyridis (Pallas), which were either allowed or not allowed to feed on aphids. Virgin females in the presence of aphids, exhibited “calling behavior”, which is commonly associated with the emission of a sex pheromone in several Coleoptera species. These calling females were found to release a blend of volatile compounds that is involved in the remote attraction (i.e., from a distance) of males. Gas Chromatography-Mass Spectrometry (GC-MS) analyses revealed that (–)-β-caryophyllene was the major constituent of the volatile blend (ranging from 80 to 86%), with four other chemical components also being present; β-elemene, methyl-eugenol, α-humulene, and α-bulnesene. In a second set of experiments, the emission of the five constituents identified from the blend was quantified daily over a 9-day period after exposure to aphids. We found that the quantity of all five chemicals significantly increased across the experimental period. Finally, we evaluated the activity of a synthetic blend of these chemicals by performing bioassays which demonstrated the same attractive effect in males only. The results confirm that female H. axyridis produce a volatile sex pheromone. These findings have potential in the development of more specific and efficient biological pest-control management methods aimed at manipulating the behavior of this invasive lady beetle. [less ▲]

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See detailFirst evidence of a volatile sex pheromone in the invasive Harmonia axyridis (Pallas) (Coleoptera: Coccinellidae)
Fassotte, Bérénice ULg; Fischer, Christophe ULg; Durieux, Delphine ULg et al

Conference (2013, September 10)

Until now, volatile sex pheromone have not been identified in the Coccinellidae, although various studies have suggested the existence of such molecules. In this work, we have sampled volatile organic ... [more ▼]

Until now, volatile sex pheromone have not been identified in the Coccinellidae, although various studies have suggested the existence of such molecules. In this work, we have sampled volatile organic compounds released in the headspace of virgin females of the multicolored Asian ladybeetle, Harmonia axyridis (Pallas), that were either allowed or not to feed on pea aphids (Acyrthosiphon pisum Harris). When fed on aphids, virgin females showed a stereotypical “calling behavior”, commonly associated with the emission of a sex pheromone in several Coleoptera species. Behavioral assays conducted with calling females in a four-arm olfactometer demonstrated that the blend of released volatile compounds was attractive for males, but not for other females. The headspace of virgin females that were not previously fed with aphids was not attractive for either sex. GC-MS analyses revealed the presence of five compounds in the volatile blend: (–)-β-caryophyllene, β elemene, methyl-eugenol, α-humulene and α-bulnesene. Subsequently, we have collected and quantified the constituents from the blend over a period of 9 days after exposure to aphids. All five compounds were produced exclusively after feeding virgin females with aphids, and their quantity significantly increased during the whole period of collection. (–)-β-caryophyllene was found to be the major constituent, representing between 80 and 89 % of the total blend. These results could promote the development of more specific and efficient management methods to manipulate the movements of this invasive ladybeetle and to reduce its negative impacts on biodiversity. [less ▲]

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See detailFirst evidence of a volatile sex pheromone in the invasive Harmonia axyridis (Pallas) (Coleoptera: Coccinellidae)
Fassotte, Bérénice ULg; Fischer, Christophe ULg; Durieux, Delphine ULg et al

Conference (2014, April 02)

Data about sex pheromones, or any semiochemicals that play a role in Coccinellid mating, remain limited. Since years, various studies and behavioral observations have hypothesized that such molecules are ... [more ▼]

Data about sex pheromones, or any semiochemicals that play a role in Coccinellid mating, remain limited. Since years, various studies and behavioral observations have hypothesized that such molecules are involved in sexual communication of ladybeetles. In this study, we collected volatile organic compounds released by virgin females of the multicolored Asian ladybeetle, Harmonia axyridis (Pallas), which were either allowed or not allowed to feed on aphids. In the presence of aphids, virgin females exhibited “calling behavior”, which has been associated with the emission of a sex pheromone in several Coleoptera species. Bioassays showed that these females released a blend of volatile compounds that is involved in the attraction of males. Gas Chromatography-Mass Spectrometry analyses highlighted specific volatile cues emanating from females, whereas males did not produce these compounds. Five components were identified: (–)-β-caryophyllene, β elemene, methyl-eugenol, α humulene, and α bulnesene. All compounds were produced after virgin females were fed aphids, and their quantity increased across the experimental period. The results confirm that female H. axyridis produce a volatile sex pheromone. Therefore, this study provides important biological information that could promote the development of efficient pest control management methods to manipulate the movements of this invasive ladybeetle, and to reduce its negative impacts on biodiversity. [less ▲]

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See detailFirst evidence of deuterotokous parthenogenesis in the tomato leafminer, Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae)
Caparros Megido, Rudy ULg; Haubruge, Eric ULg; Verheggen, François ULg

in Journal of Pest Science (2012)

The tomato leafminer, Tuta absoluta (Lepidoptera: Gelechiidae), originates from South America and is now considered to be one of the most damaging invasive pests of tomatoes in the Mediterranean Basin ... [more ▼]

The tomato leafminer, Tuta absoluta (Lepidoptera: Gelechiidae), originates from South America and is now considered to be one of the most damaging invasive pests of tomatoes in the Mediterranean Basin countries of Europe and North Africa. The preventing pest mating control methods include: (1) the use of synthetic pheromones for male attraction and annihilation inside insecticide-containing traps; (2) mating disruption by saturating the atmosphere with sex pheromones which alter the ability of males to locate females; and (3) massive applications of sterile males to alter the overall reproductive success of the pest population. However, all these methods achieve only a poor success rate in controlling T. absoluta populations under greenhouse conditions. Sex pheromone management and sterile insect techniques are both based on an important biological trait: the insect must breed through sexual reproduction. Here, we report for the first time laboratory evidence of deuterotokous parthenogenesis, an asexual reproduction where both males and females are produced from unfertilized eggs. We discuss the consequences for T. absoluta control strategies. [less ▲]

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See detailFirst evidence of Devonian strata in sweden - Palynological study of the Övedskloster drillcores 1 and 2 from Skåne
Mehlqvist, K; Vajda, V; Steemans, Philippe ULg

Conference (2014, January 08)

Detailed reference viewed: 20 (2 ULg)