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)
Is the multicolored Asian ladybeetle, Harmonia axyridis, the most abundant natural enemy to aphids in agroecosystems?
Vandereycken, Axel ; Durieux, Delphine ; Joie, Emilie et al
in Journal of Insect Science [=JIS] (2013), 13(158), 1-14
The multicolored Asian ladybeetle, Harmonia axyridis Pallas (Coleoptera: Coccinellidae), was introduced into Western Europe in the late 1990s. Since the late 2000s, this species has been commonly ... [more ▼]
The multicolored Asian ladybeetle, Harmonia axyridis Pallas (Coleoptera: Coccinellidae), was introduced into Western Europe in the late 1990s. Since the late 2000s, this species has been commonly considered one of the most abundant aphid predators in most Western European coun- tries. In spite of the large amount of research on H. axyridis, information concerning its relative abundance in agroecosystems is lacking. This study aims to evaluate the abundance of H. axyridis within the aphidophage community in four crops situated in southern Belgium: wheat, Triticum aestivum L. (Poales: Poaceae), corn, Zea mays, potato, Solanum tuberosum (Solanales: Solanaceae), and broad bean Vicia faba (Fabales: Fabaceae). In order to assess the species diver- sity, the collected data were analyzed by considering (1) the species richness and (2) the evenness according to the Shannon diversity index. Eleven aphidophages were observed in every invento- ried agroecosystem, including five abundant species: three coccinellids, the seven-spotted ladybug, Coccinella septempunctata L. (Coleoptera: Coccinellidae), the 14-spotted Ladybird, Propylea quatuordecimpunctata, and H. axyridis; one hoverfly, the marmalade hoverfly, Episyr- phus balteatus De Geer (Diptera: Syrphidae); and one lacewing, the common green lacewing, Chrysoperla carnea Stephens sensu lato (= s.l.) (Neuroptera: Chrysopidae). Harmonia axyridis has been observed to thrive, breed, and reproduce on the four studied crops. Harmonia axyridis is the most abundant predator of aphids in corn followed by C. septempunctata, which is the main aphid predator observed in the three other inventoried crops. In wheat and potato fields, H. axyridis occurs in low numbers compared to other aphidophage. These observations suggest that H. axyridis could be considered an invasive species of agrosystems, and that potato and wheat may intermittently act as refuges for other aphidophages vulnerable to intraguild predation by this invader. Harmonia axyridis is not the most abundant aphid predator in the main Belgian crops. [less ▲]Detailed reference viewed: 28 (7 ULg)
Is the neutrophil a worthy target in severe asthma and chronic obstructive pulmonary disease?
Louis, Renaud ;
in Clinical & Experimental Allergy : Journal of the British Society for Allergy & Clinical Immunology (2006), 36(5), 563-567Detailed reference viewed: 5 (0 ULg)
Is the noxious Ambrosia artemisiifolia L. going to invade Belgium?
Ortmans, William ; ; Mahy, Grégory et al
Poster (2014, February 07)
Ambrosia artemisiifolia L. is an invasive species from North America, causing a health crisis in Europe due to its highly allergenic pollen. In France, there is a zone where the A. artemisiifolia ... [more ▼]
Ambrosia artemisiifolia L. is an invasive species from North America, causing a health crisis in Europe due to its highly allergenic pollen. In France, there is a zone where the A. artemisiifolia populations are naturalized and invasive. Outside this area, populations are more rare and do not seem to expand. We tested if the performances of A. artemisiifolia are varying with competition level, and among geographical zones. The results show that populations from Belgium and Netherlands are not less efficient than invasive populations for the measured traits. [less ▲]Detailed reference viewed: 54 (12 ULg)
IS THE PRESENCE OF MESOTROPHIC PLANT-COMMUNITIES IN THE PEAT-BOGS OF HAUTES-FAGNES (BELGIUM) CONNECTED WITH TONALITE INTRUSIONS IN THE REVINIAN LAYERS
Hambuckers, Alain ; Schumacker, René ; Remacle, Jean et al
in Belgian Journal of Botany (1995), 128(1), 48-56
Within the Hautes-Fagnes Nature Reserve (Belgium) acidic and oligotrophic biotopes are developing on very acidified stony silt raised bogs. However, they are locally dominated by mesotrophic species ... [more ▼]
Within the Hautes-Fagnes Nature Reserve (Belgium) acidic and oligotrophic biotopes are developing on very acidified stony silt raised bogs. However, they are locally dominated by mesotrophic species. Based on the fact that there are several outcrops of tonalite in the region and particularly one in the Nature Reserve, a hypothesis to explain these singularities of the vegetation implies discontinuities of the bedrock provoked by intrusions of this magmatic rock in the Revinian layer covering the region. Seventeen plots containing Phragmites australis were examined and vegetation was described. Silt and soil water were sampled and analyzed for mineral contents in 15 sites. The differences of mineral composition between the P. australis plots and their surrounding environment confirmed the more mesotrophic characteristics of these plots (i.e. higher pH, higher Ca and Mg contents, lower Al content). However, the lower Zn, Pb and Fe contents would lead to reject the hypothesis of intrusions of tonalite since these elements are more abundant in the tonalite and its mineralization than in the Revinian rock. Nevertheless, the overall ecological conditions of the examined plots and the differences of plant species composition suggested that the observed chemical environment could be evoked for explaining the distribution of the mesotrophic species in the oligotrophic environment of the Nature Reserve. Consequently, an alternative hypothesis is proposed. [less ▲]Detailed reference viewed: 28 (3 ULg)