Is the (E)-ß-farnesene only volatile terpenoid in aphids?
Francis, Frédéric ; Vandermoten, Sophie ; Verheggen, François et al
in Journal of Applied Entomology (2005), 129
Herbivore insects use a broad range of chemical cues to locate their host to feed or to oviposit. Whether several plant volatiles are effective allelochemicals for insects, the latter also emit molecules ... [more ▼]
Herbivore insects use a broad range of chemical cues to locate their host to feed or to oviposit. Whether several plant volatiles are effective allelochemicals for insects, the latter also emit molecules which have infochemical role. The (E)-beta-farnesene (EBF) is a well-known aphid alarm pheromone commonly found in all previously tested species. Analysis of the released molecules from 23 aphid species, mainly collected on their natural host plant from May to July, was performed by gas chromatography–mass spectrometry. While EBF was identified as the main volatile substance in 16 species, alone or associated with other molecules, the alarm pheromone was only a minor component of the volatile molecule pattern of five other species. Moreover, two species, Euceraphis punctipennis and Drepanosiphum platanoides, did not release EBF at all but other terpenes were identified. This original observation raised the question on the utility and the source of the non-EBF volatiles. Are these potential infochemical substances produced by the aphid or only absorbed from the host plant? Here we determined that terpenes released by insects were not only provided by the host plants. Indeed, Megoura viciae emitted additional molecules than the ones from several aphid species reared on the same host plant. Moreover, no systematic relation between the feeding behaviour of the aphid species and the volatile releases was observed. Aphid terpene composition and proportion would provide reliable cues to identify the emitting organism, plant or insect. The next step of this work will be to determine the infochemical role of terpenes found in the range of tested aphid samples to better understand the relations between the different tritrophic levels. [less ▲]Detailed reference viewed: 107 (27 ULg)
Is the ADA/EASD algorithm for the management of type 2 diabetes (January 2009) based on evidence or opinion? A critical analysis.
; ; et al
in Diabetologia (2010)
The ADA and the EASD recently published a consensus statement for the medical management of hyperglycaemia in patients with type 2 diabetes. The authors advocate initial treatment with metformin ... [more ▼]
The ADA and the EASD recently published a consensus statement for the medical management of hyperglycaemia in patients with type 2 diabetes. The authors advocate initial treatment with metformin monotherapy and lifestyle modification, followed by addition of basal insulin or a sulfonylurea if glycaemic goals are not met (tier 1 recommendations). All other glucose-lowering therapies are relegated to a secondary (tier 2) status and only recommended for selected clinical settings. In our view, this algorithm does not offer physicians and patients the appropriate selection of options to individualise and optimise care with a view to sustained control of blood glucose and reduction both of diabetes complications and cardiovascular risk. This paper critically assesses the basis of the ADA/EASD algorithm and the resulting tiers of treatment options. [less ▲]Detailed reference viewed: 46 (1 ULg)
Is the aroma compound g-decalactone produced by yeast in response to a membrane-rigidifying stress induced by the biotransformation medium?
Aguedo, Mario ; ; et al
in Chemické Listy (2003, June), 97Detailed reference viewed: 9 (1 ULg)
Is the baboon model appropriate for endometriosis studies?
; ; et al
in Fertility and Sterility (2011), 96(3), 728-7333
Objective To determinethe prevalence of spontaneous endometriosis andthe incidence of induced endometriosis after endocervical canal resection in baboons. Design Induction and follow-up of endometriosis ... [more ▼]
Objective To determinethe prevalence of spontaneous endometriosis andthe incidence of induced endometriosis after endocervical canal resection in baboons. Design Induction and follow-up of endometriosis in baboons, which is one of the primate species that develop spontaneous endometriosis. Forty-one baboons were checked for the presence of spontaneous endometriosis. We then attempted to induce endometriosis in 30 of them by endocervical canal resection. Setting Institute of Primate Research, Nairobi, Kenya, and Catholic University of Louvain, Brussels, Belgium. Animal(s) Forty-one baboons were checked for spontaneous endometriosis and 30 of them were used to develop a model of induced endometriosis. Intervention(s) A total of 41 baboons underwent diagnostic laparoscopy for 10 months. In a first step, 30 of this number subsequently underwent endocervical canal resection. In a second step, 20 of the 30 underwent uterine horn resection. Main Outcome Measure(s) Follow-up by laparoscopy. Result(s) Two of the 41 baboons were diagnosed with spontaneous endometriosis (4.8%). Twelve months after the surgical procedure to induce endometriosis, 8 of 29 animals presented with endometriotic lesions diagnosed by using laparoscopy and confirmed by histologic examination. The incidence of induced endometriosis in our model was thus 27.6%. In 2 baboons, endometriosis disappeared over time, resulting in a final rate of 20.7% (6/29). Conclusion(s) The rate of spontaneous endometriosis is very low (4.8%). Endometriosis can be induced (with a rate of just 27.6%) by endocervical canal resection to stimulate retrograde menstruation. [less ▲]Detailed reference viewed: 12 (1 ULg)
Is the behaviour of grazing cattle influenced by the presence of a hedge in the pasture?
Vandermeulen, Sophie ; ; et al
Poster (2014, February 07)
The interest in using shrubs and trees as forage for cattle is raising in temperate regions, along with the environmental measures promoting hedges along pasture. This study aimed at determining the ... [more ▼]
The interest in using shrubs and trees as forage for cattle is raising in temperate regions, along with the environmental measures promoting hedges along pasture. This study aimed at determining the influence of the presence of a woody hedge on grazing cattle behavior as well as the evolution of this behavior during the grazing season. Twelve heifers were set to graze a standard ryegrass and clover meadow during the grazing season of 2013. The animals were divided in 2 groups : one with a free access to a hedge composed by 10 temperate shrub and tree species, the other with no access to a hedge (control). Their behavior (grazing, browsing and other activities) was monitored during 14h d-1 replicated 3d week-1 during 3 periods (May, July and September). Results suggest that both season and presence of a hedge have an influence on the behavior of heifers. Grazing, resting and rumination varied between the two groups in each period (P<0.05). The time spent browsing was influenced by the season (P<0.001); the heifers with an access to the hedge could browse 19.3% of the total time in May against 5.9 and 5.4% in July and September. Both control and experimental heifers grazed more with the progressing season, but the animals without the hedge grazed always more than the heifers that could graze and browse (49.6 vs 43.0%). In conclusion, browsing woody species represents a significant part of the time spent for forage ingestion, and variation in this behavior over the whole grazing season requires to investigate the influence of both pasture and browse availability and composition. [less ▲]Detailed reference viewed: 14 (8 ULg)
Is the bowshock of the runaway massive star HD 195592 a Fermi source?
; ; De Becker, Michaël
in Astronomy and Astrophysics (2013), 550
HD 195592 is an O-type super-giant star, known as a well-established runaway. Recently, a Fermi gamma-ray source (2FGL J2030.7+4417) with a position compatible with that of HD 195592 has been reported ... [more ▼]
HD 195592 is an O-type super-giant star, known as a well-established runaway. Recently, a Fermi gamma-ray source (2FGL J2030.7+4417) with a position compatible with that of HD 195592 has been reported. Our goal is to explore the scenario where HD 195592 is the counterpart of the Fermi gamma-ray source modeling the non-thermal emission produced in the bowshock of the runaway star. We calculate the spectral energy distribution of the radiation produced in the bowshock of HD 195592 and we compare it with Fermi observations of 2FGL J2030.7+4417. We present relativistic particle losses and the resulting radiation of the bowshock of HD 195592 and show that the latter is compatible with the detected gamma-ray emission. We conclude that the Fermi source 2FGL J2030.7+4417 might be produced, under some energetic assumptions, by inverse Compton up-scattering of photons from the heated dust in the bowshock of the runaway star. HD 195592 might therefore be the very first object detected belonging to the category of gamma-ray emitting runaway massive stars, whose existence has been recently predicted. [less ▲]Detailed reference viewed: 71 (30 ULg)
Is the cerebral cortex hyperexcitable or hyperresponsive in migraine?
; ; Schoenen, Jean
in Cephalalgia : An International Journal of Headache (2007), 27(12), 1429-1439
Although migraineurs appear in general to be hypersensitive to external stimuli, they maybe also have increased daytime sleepiness and complain of fatigue. Neurophisiological studies between attacks have ... [more ▼]
Although migraineurs appear in general to be hypersensitive to external stimuli, they maybe also have increased daytime sleepiness and complain of fatigue. Neurophisiological studies between attacks have shown that for a number of different sensory modalities the migrainous brain is characterised by a lack of habituation of evoked responses. Whether this is due to increased cortical hyperexcitability, possibly due to decreased inhibition, or to an abnormal responsivity of the cortex due a decreased preactivation level remains disputed. Studies using transcranial magnetic stimulation in particular have yielded contradictory results. We will review here the available data on cortical excitability obtained with different methodological approaches in patients over the migraine cycle. We will show that these data congruently indicate that the sensory cortices of migraineurs react excessively to repetitive, but not to single, stimuli and that the controversy above hyper- versus hypo-excitability is merely a semantic misunderstanding. Describing the migrainous brain as 'hyperresponsive' would fit most of the available data. Deciphering the precise cellular and molecular underpinnings of this hyperresponsivity remains a challenge for future research. We propose, as a working hypothesis, that a thalamo-cortical dysrhythmia might be the culprit. [less ▲]Detailed reference viewed: 24 (0 ULg)
Is the CXC-Chemokine CXCL8 involved in the breed predisposition of west highland white terrier to canine idiopathic pulmonary fibrosis ?
Roels, Elodie ; Krafft, Emilie ; et al
in Proceedings of the 23th ECVIM Meeting (2013, September)Detailed reference viewed: 20 (3 ULg)
Is the decline of euroopean black grouse populations due to the global climate change ?
Loneux, Michèle ; ; Poncin, Pascal
Poster (2007)Detailed reference viewed: 5 (0 ULg)
Is the decrease of central venous compliance the factor responsible for salt sensitivity?
Krzesinski, Jean-Marie ; Rorive, Georges
in Journal of Hypertension (Supplement) (1986), 4
To detect the possible mechanisms of salt sensitivity, blood pressure (BP), renal biological and red blood cell (RBC) ionic fluxes, responses were studied in 20 normotensive males (<30 years old), after ... [more ▼]
To detect the possible mechanisms of salt sensitivity, blood pressure (BP), renal biological and red blood cell (RBC) ionic fluxes, responses were studied in 20 normotensive males (<30 years old), after acute isotonie saline infusion (1 litre in less than 30 min). Salt sensitivity was considered to be present if mean supine BP increased by more than 9 mmHg when the salt diet, which was applied each time for 1 week, increased from less than 20 mmol/l NaCI per day to more than 340 mmol/l. Three subgroups were defined: eight salt-sensitives (SS), 10 salt-resistants (SR) and two patients with only a very slight BP increase. ln each group (SS or SR), the same percentage of family history of hypertension was noted (60%). During the normal diet (± 170 mmol/l NaCl per day), vascular resistances were lower , and creatinine clearance higher in SS (26 ± 8 units, and 122 ± 6 ml/min, respectively) than in SR (48 ± 1 units and 102 ± 1 ml/min). As other markers of greater salt overloading could not be detected in SS, these differences could be due to higher cardiac volume ejection in SS than in SR (heart rate was the same in the two populations. During acute salt loading, mean BP rase in SS (tram 88 ± 6 to 93 ± 7 mmHg), while it decreased in SR (from 85 ± 10 to 81 ± 10 mmHg, P < 0.05). During the same period RBC Na+K+-ATPase activity decreased more in SS (from 3970 ± 715 to 3312 ± 452 umol/l cell per h) than in SR (from 4430 ± 550 to 4300 ± 520). Moreover, during chronic oral salt loading (> 340 mmol/l NaCl per day) , SS showed a greater BP increase during noradrenaline (NE) infusion (10 ± 6 mmHg for 60 ng/min per kg NA) than in SR (5 ± 3 mmHg, P < 0.02). In conclusion, salt sensitivity is already present in young normotensives. It could be due to a higher sympathetic venous tone , which in turn would increase cardiac output and secretio n of a plasma Na+K+-pump inhibitor. [less ▲]Detailed reference viewed: 10 (0 ULg)
Is the decremental motor response a useful parameter for the follow-up of amyotrophic lateral sclerosis patients ?
WANG, François-Charles ; DE PASQUA, Victor ; Delwaide, Paul
in Journal of Neurology (2000)Detailed reference viewed: 5 (1 ULg)
Is the evolution of myocardial infarction haptoglobin phenotype-dependent?
Chapelle, Jean-Paul ; Albert, Adelin ; Kulbertus, Henri et al
Poster (1981)Detailed reference viewed: 6 (1 ULg)
Is the external beam PIXE method suitable for determining ancient silver artifact fineness?
Weber, Georges ; ; Strivay, David et al
in Nuclear Instruments & Methods in Physics Research Section B (2000), 161
In archeometry, the non-destructive characteristic of an analytical method is always very attractive. For most of techniques, besides the need of sampling, difficulties can originate from the shape and ... [more ▼]
In archeometry, the non-destructive characteristic of an analytical method is always very attractive. For most of techniques, besides the need of sampling, difficulties can originate from the shape and the size of the silver artifacts to be analyzed. The external PIXE method should be an answer to this problem but several questions are arising from the implementation of the technique to such a material. The aim of this paper is to specify the experimental procedure as to take into account several parameters, which could induce dramatic errors. Among them it can be pointed out the superficial enrichment in silver, arising from the dissolution of copper and copper oxide, the surface roughness effects, the great importance of the stability of the geometric conditions. The accuracy and the precision of the method are considered within the scope of the results obtained in ancient times by the cupellation with ashbone cupels. In addition. the process involved to obtain silver alloys has been studied in order to define its influence on the real fineness of the objects. (C) 2000 Elsevier Science B.V. All rights reserved. [less ▲]Detailed reference viewed: 16 (3 ULg)
Is the feeling of familiarity driven by weak recollection as well as by an independent familiarity mechanism?
; Bastin, Christine ; et al
in Journal of Cognitive Neuroscience (2003), 15(Supplemental), 179
The aim of this experiment is to examine how recollection and familiarity change over time and whether there is a qualitative difference between familiar items that were previously recollected and items ... [more ▼]
The aim of this experiment is to examine how recollection and familiarity change over time and whether there is a qualitative difference between familiar items that were previously recollected and items that have always been familiar. It might be that, when an item is initially recollected and becomes just familiar after a delay, this form of familiarity is actually a weak and partial recollection, qualitatively different from mere familiarity. To address this issue, a task have been developed in which, at study, participants encoded two series of 100 pictures representing scenes under respectively shallow and deep encoding conditions. Memory for these pictures was tested by means of a yes-no recognition test. Recognised items were classified as recollected or as familiar. Half of the pictures from each encoding condition were tested after 10 minutes and the other half were tested after 2 days. The results indicated that recollection decreased after 2 days while familiarity increased (deep encoding condition) or did not change (shallow encoding condition). This suggests that, among the items judged as familiar after 2 days, some items would have been recollected after 10 minutes and some were initially already familiar. Because deep encoding produced a higher proportion of recollection at the 10-minute interval, the proportion of recollection-changed-into-familiarity responses should be greater in this condition than in the shallow encoding condition. Whether there is a qualitative difference between these responses and pure familiarity responses should be explored in a fMRI experiment. [less ▲]Detailed reference viewed: 20 (0 ULg)
Is the fishery of the introduced Tanganyika sardine (Limnothrissa miodon) in Lake Kivu (East Africa) sustainable?
; Darchambeau, François ; et al
in Journal of Great Lakes Research (2012), 38(3), 524-533
Limnothrissa miodon, a small pelagic clupeid fish introduced at the end of the 1950s into Lake Kivu, became an important resource for the human populations of this area. The total stock of pelagic fish ... [more ▼]
Limnothrissa miodon, a small pelagic clupeid fish introduced at the end of the 1950s into Lake Kivu, became an important resource for the human populations of this area. The total stock of pelagic fish populations of this lake was estimated in 2008 by two hydroacoustic surveys, using an EK60 split-beam sounder (frequency 70. kHz). The total fish stocks were estimated to be approximately 5000. t in the rainy season and 6000 tons in the dry season. These values are similar to previous estimations performed in the 1980s. During 2008, the stock did not fluctuate throughout the seasons; however, the spatial distributions were different in the two hydrological seasons. Interestingly, the L. miodon stock has appeared to remain stable over the last two decades, which suggests that the pelagic fishery in Lake Kivu has not been overexploited and that it is sustainable. © 2012 Elsevier B.V. [less ▲]Detailed reference viewed: 21 (2 ULg)
Is the fishing village of Phan Thiet victim of climate change ?
in Geo-Eco-Trop : Revue Internationale de Géologie, de Géographie et d'Ecologie Tropicales (2012), 36
Warming of the climate system is unequivocal, as it is now evident from observations of increases in global average air and ocean temperatures, widespread melting of snow and ice and rising global average ... [more ▼]
Warming of the climate system is unequivocal, as it is now evident from observations of increases in global average air and ocean temperatures, widespread melting of snow and ice and rising global average sea level. In this framework, sea level rise is virtually certain. This will impact ecosystems, coastal areas, human health, and economies. Vietnam is very likely to be one of the most affected countries with its 3200 km of shorelines with amplified vulnerability in large areas already affected by subsidence such as the Mekong and Red River deltas. In January 2009, international broadcast news have relayed the information that 27 houses located on the southern coast of Vietnam, in the fishing village of Phan Thiet, 200 km east of Ho Chi Minh City, have collapsed and that another hundred buildings were also threatened of destruction. According to experts, this event was definitely one of the consequences of global warning. This article shows, using the multi dates of Google Earth, that this assumption is not correct and highlights the real causes of this rapid and inevitable retreat of the coastline in this village, namely the mismanagement of natural resources, the lack of land use planning and the non-existence of policies focused on natural hazard management in the uncontrolled construction the seaside resort of Mui Ne, a few kilometers east. [less ▲]Detailed reference viewed: 100 (13 ULg)
Is the functioning of the phonological short-term memory different in Dwn's syndrome and in normally developing children
Poster (1997, April 09)Detailed reference viewed: 12 (0 ULg)
Is the Greenland ice sheet beginning to melt?
; Fettweis, Xavier
in La Lettre « Changement Global » PIGB - PMRC France (2008), 21
Using a new evaluation of satellite data, and simula- tions carried out with a regional climate model, it has been shown that the acceleration of surface melting of the Greenland ice sheet during the 1979 ... [more ▼]
Using a new evaluation of satellite data, and simula- tions carried out with a regional climate model, it has been shown that the acceleration of surface melting of the Greenland ice sheet during the 1979-2005 period was twice as rapid as earlier studies had estimated. Between 1979 and 2005, the area of Greenland affected by melt at least one day per year in fact increased by 42%, and the average summer tempera- ture rose by 2.4°C. [less ▲]Detailed reference viewed: 4 (0 ULg)
Is the Hagberg Falling Number always linked to the a - amylase activity of wheat ?
; ; et al
Scientific conference (2002, September 25)Detailed reference viewed: 21 (1 ULg)
Is the KIID sufficient to associate portfolios to investor profiles?
in Bankers, Markets, Investors [=BMI] (2012), (118), 14-22
With the Key Investor Information Document (KID), the new UCITS IV framework brings a useful standardized and simplified scheme to explain the risk of mutual funds to non-professional investors. The ... [more ▼]
With the Key Investor Information Document (KID), the new UCITS IV framework brings a useful standardized and simplified scheme to explain the risk of mutual funds to non-professional investors. The Synthetic Risk and Reward Indicator (SRRI) methodology defines how to assess a volatility equivalent for each type of funds, and recognizes the specificities of various types of investment vehicles in the process. The SRRI rests upon two key principles: (i) risk-volatility mapping: the level of risk can be adequately translated by the volatility of returns; and (ii) reward to volatility: there must be a positive connection between the level of risk borne by the individual investor and the associated reward in terms of returns. We show that the SRRI methodology does not guarantee that these two principles are respected in practice. By forcing any type of risk to be translated into a volatility estimate, the approach overlooks investor’s heterogeneity in the definition of risk. The SRRI synthetic approach is powerless to adequately reflect the trade-off between normal and extreme risks the way it is perceived by individual investors. It also ignores that fund returns are not necessarily only related to volatility. We show that the KID does not replace a proper investment profiling system. The analysis of investor profiles is a necessary complement to the KID in order to provide adequate advice to investors. We provide an approach, based on the linear-exponential utility function, that enables the financial advisor to address the heterogeneity of investors when defining the risk of an investment portfolio. [less ▲]Detailed reference viewed: 126 (21 ULg)