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See detailGamma Dor and Gamma Dor - Delta Sct Hybrid Stars In The CoRoT LRa01
Hareter, M.; Reegen, P.; Miglio, A. et al

E-print/Working paper (2010)

A systematic search for gamma Dor and gamma Dor - delta Scuti hybrid pulsators was conducted on the CoRoT LRa01 Exo-archive yielding a total of 418 gamma Dor and 274 hybrid candidates. After an automatic ... [more ▼]

A systematic search for gamma Dor and gamma Dor - delta Scuti hybrid pulsators was conducted on the CoRoT LRa01 Exo-archive yielding a total of 418 gamma Dor and 274 hybrid candidates. After an automatic jump correction 194 and 167 respectively, show no more obvious jumps and were investigated in more detail. For about 25\% of these candidates classification spectra from the Anglo-Australian Observatory (AAO) are available. The detailed frequency analysis and a check for combination frequencies together with spectroscopic information allowed us to identify I) 34 gamma Dor stars which show very different pulsation spectra where mostly two modes dominate. Furthermore, a search for regularities in their oscillation spectra allowed to derive recurrent period spacings for 5 of these gamma Dor stars. II) 25 clear hybrid pulsators showing frequencies in the gamma Dor and delta Sct domain and are of A-F spectral type. [less ▲]

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See detailGamma Emitting Radionuclides in Soils from Selected Areas in Douala-Bassa Zone, Littoral Region of Cameroon
Ndontchueng Moyo, Maurice; Mekongtso Nguelem, Eric Jilbert; Augustin, Simo et al

in Hindawi Publishing Corporation (2014), 2014

A study of natural radioactivity levels in some composites of eighteen soil samples selected within Douala-Bassa zone of Littoral Region has been evaluated. The samples were analysed using gamma ... [more ▼]

A study of natural radioactivity levels in some composites of eighteen soil samples selected within Douala-Bassa zone of Littoral Region has been evaluated. The samples were analysed using gamma spectrometry based broad energy germanium detector (BEGe 6350). The activity profile of radionuclide shows low activity across the studied areas. The obtained mean values of 226Ra, 232Th, and 40K in the two campuses were 25.48 Bq/kg, 65.96 Bq/kg, and 39.14 Bq/kg for Campus 1 and 24.50 Bq/kg, 66.71 Bq/kg, and 28.19 Bq/kg for Campus 2, respectively. In terms of health analysis, some radiation health hazard parameters were calculated within the two campuses. The mean values of radium equivalent activity were 122.81 Bq/kg and 122.08 Bq/kg, absorbed dose rate in air was 99.13 nGy/h and 98.18 nGy/y, annual outdoor effective dose was 0.12 mSv/y and 0.12 mSv/y, and external health hazard index was 0.34 and 0.33 in Campus 1 and Campus 2, respectively. These health hazard parameters were seen to be below the safe limit of UNSCEAR 2000 except the absorbed dose rate in air and the annual outdoor effective doses which are relatively high compared to the values of 60 nGy/h and 0.07 mSv/y. These results reveal no significant radiological health hazards for inhabitance within the study areas. [less ▲]

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See detailGamma interferon production and plasma concentrations of pregnancy-associated glycoproteins 1 and 2 in gestating dairy cows naturally infected with Neospora caninum.
Serrano-Perez, B; Garcia-Ispierto, I; Melo de Sousa, Noelita ULg et al

in Reproduction in Domestic Animals (2014), 49(2), 275-280

Gamma interferon (IFN-γ) production and cross-breed pregnancy have been attributed a role in protecting dairy cows infected with Neospora caninum against abortion. Plasma levels of pregnancy-associated ... [more ▼]

Gamma interferon (IFN-γ) production and cross-breed pregnancy have been attributed a role in protecting dairy cows infected with Neospora caninum against abortion. Plasma levels of pregnancy-associated glycoproteins-1 (PAG-1) are a marker of placental/foetal well-being and of PAG-2 is an abortion risk indicator in chronically N. caninum-infected animals. The present study examines, in cross-breed pregnancies, interactions between IFN-γ production and levels of PAG-1 and PAG-2 in non-aborting naturally Neospora-infected dairy cows. Data were obtained from 60 pregnant Holstein-Friesian cows: 44 Neospora-seropositive and 16 Neospora-seronegative; 12 became pregnant using Holstein-Friesian semen and 48 using Limousin semen. Blood samples were collected on Days 40, 90, 120, 150, 180 and 210 of gestation. Gamma interferon was only detected in the plasma of nine of the 44 Neospora-seropositive cows, all of them became pregnant using Limousin semen. Through GLM procedures, in cows inseminated with Limousin semen and Neospora-seropositive cows showing no IFN-γ production, PAG-1 concentrations were high and increased throughout gestation compared to the levels detected in cows inseminated with Holstein-Friesian semen and Neospora-seropositive cows producing IFN-γ, respectively. In Neospora-seronegative cows and in Neospora-seropositive cows showing no IFN-γ production, significantly increased PAG-2 concentrations were observed on gestation Day 120. Our findings indicate that IFN-γ production correlates negatively and the production of antibodies against N. caninum is uncorrelated with plasma PAG concentrations during gestation in Neospora-infected dairy cows. Accordingly, IFN-γ production could be linked to the transplacental migration of tachyzoites, which may cause a reduction in PAG levels. [less ▲]

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See detailGamma interferon production correlates negatively with plasma levels of pregnancy-associated glycoprotein-1 (PAG-1) during gestation in dairy cows naturally infected with Neospora caninum
Lopez-Gatius, F.; Almeria, S.; Yániz, J. L. et al

in O’Leary, M.; Arnett, J. (Eds.) Pregnancy Protein Research (2009)

Gamma interferon (IFN-γ) production has been ascribed a role in protecting cows infected with Neospora caninum against abortion. The present study analyzes the interaction between IFN-γ production and ... [more ▼]

Gamma interferon (IFN-γ) production has been ascribed a role in protecting cows infected with Neospora caninum against abortion. The present study analyzes the interaction between IFN-γ production and levels of plasma pregnancy-associated glycoprotein-1 (PAG-1), as a marker of placental/fetal well-being, throughout gestation in naturally Neospora-infected dairy cows. Data were obtained from 88 pregnant cows from two herds: 62 seropositive and 26 seronegative for the parasite. Blood sample collection was performed on days 40, 90, 120, 150, 180 and 210 of gestation. Plasma was tested for antibodies against N. caninum, PAG-1 and IFN-γ. Twenty five (28.4%) pregnancies were recorded after AI using Holstein-Friesian semen (19 in seronegative and 6 in seropositive animals), and 63 (71.6%) after AI using Limousin semen (7 in seronegative and 56 in seropositive animals). Gamma interferon was detected in the plasma of 14 (22.6%) of the 62 Neospora-seropositive cows and could not be detected in any of the 26 seronegative animals. All 14 cows producing IFN-γ became pregnant by using Limousin semen. Our GLM repeated measures showed no effect of herd, lactation number, milk production at the time of pregnancy diagnosis and Neospora-seropositivity on plasma PAG-1 concentrations. Significant positive effects of both the day of gestation (P<0.0001) and interaction between day of gestation and breed of sire (P = 0.001) on PAG-1 values were registered. Cows carrying twins had higher (P = 0.002) PAG-1 concentrations throughout gestation than cows carrying singletons. Interactions between breed of sire and Neospora-seropositivity (P<0.0001), and between IFN-γ production and Neospora-seropositivity (P = 0.04) were also detected. Thus, Neospora-seronegative cows inseminated with Limousin and Neospora-seropositive cows with no IFN-γ production, exhibited higher PAG-1 concentrations throughout gestation than seropositive cows inseminated with Limousin semen and producing IFN-γ, respectively. Our data indicate that production of IFN-γ correlates negatively and, the production of antibodies against N. caninum is uncorrelated with plasma PAG-1 concentrations during gestation in Neospora-infected dairy cows. Our results also suggest that augmented Th1 cell-mediated immunity is related to a lower risk of abortion and therefore higher resistance to the parasite in cows inseminated with Limousin versus Holstein-Friesian semen. [less ▲]

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See detailGamma knife surgery for facial nerve schwannomas.
Litré, Claude Fabien ULg; Gourg, GP; Tamura, M et al

in Neurosurgery (2007), 60(5), 853-9

Radical resection of facial nerve schwannomas classically implies a high risk of severe facial palsy. Owing to the rarity of facial palsy after gamma knife surgery (GKS) of vestibular schwannomas ... [more ▼]

Radical resection of facial nerve schwannomas classically implies a high risk of severe facial palsy. Owing to the rarity of facial palsy after gamma knife surgery (GKS) of vestibular schwannomas, functional evaluation after GKS seems rational in this specific group of patients. To our knowledge, no previous similar evaluation exists in the literature. [less ▲]

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See detailGamma radiation induced modifications of tapioca starch
Atrous, Hager; Benbettaïeb, Nasreddine; Hosni, Faouzi et al

in Asian Academic Research Journal of Multidisciplinary (2016), 3(3), 187-220

The effect of gamma radiation (3, 5, 10, 20, 35 and 50 kGy) on the morphological, structural, physicochemical, pasting and thermal properties of tapioca starch was studied. Microphotographs of scanning ... [more ▼]

The effect of gamma radiation (3, 5, 10, 20, 35 and 50 kGy) on the morphological, structural, physicochemical, pasting and thermal properties of tapioca starch was studied. Microphotographs of scanning electron microscopy and polarized light microscopy revealed the absence of morphological changes induced by gamma radiation. The X-ray diffraction spectra showed that irradiation treatment did not influence the shape and intensity of X-ray diffraction peaks. The presence of free radicals in the irradiated tapioca starch was confirmed by electron spin resonance spectrometry. Fourier transform infrared spectroscopy showed that the irradiated starch displayed a significant decrease in the intensity of the O–H and C–H stretches, bending modes of water and glycosidic linkages. Irradiation improved the water solubility index of starch granules and depressed the apparent amylose content. An increase in the swelling power was observed after irradiation treatment until 20 kGy, followed by a decrease at higher doses. Brabender viscoamylograph test showed that the maximal consistency of the starch paste decreased significantly with increasing irradiation dose. There was no significant difference in the gelatinization temperatures, as well as the corresponding transition enthalpies among native and irradiated tapioca starch samples, as shown in the differential scanning calorimetry thermograms. [less ▲]

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See detailGamma(5) quasiparticles and avoided quantum criticality in U(Ru,Rh)(2)Si-2
Silhanek, Alejandro ULg; Harrison, N.; Batista, C. D. et al

in Physica B: Condensed Matter (2006), 378-80

We discuss recent specific heat data in high magnetic fields on URu2Si2 and 4% Rh-doped URu2Si2 as well as previously published de Haas-van Alphen data at lower magnetic fields in pure URu2Si2: both of ... [more ▼]

We discuss recent specific heat data in high magnetic fields on URu2Si2 and 4% Rh-doped URu2Si2 as well as previously published de Haas-van Alphen data at lower magnetic fields in pure URu2Si2: both of which are consistent with quasiparticle bands formed from a hybridization between 5f-electron Gamma(5) doublets and regular conduction electrons. The system exhibits itinerant electron metamagnetism that gives rise to a putative quantum critical point at similar to 34-37T (depending on the % of Rh) that is subsequently unstable to field-induced phases. (c) 2006 Elsevier B.V. All rights reserved. [less ▲]

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See detailGamma-aminobutyric acid-sub(A) agonists differentially gnawing induced by indirect-acting dopamine agonists in C57BL/6J mice
Tirelli, Ezio ULg; Geter-Douglass, B.; Witkin, J. M.

in Journal of Pharmacology and Experimental Therapeutics (The) (1998), 284(1), 116-124

Evaluated the interaction of either gaboxadol HCl (THIP) or muscimol, both gamma-aminobutyric acid (GABA) type A agonists, with indirect-acting dopamine agonists (DAGs) methylphenidate, (+)-amphetamine ... [more ▼]

Evaluated the interaction of either gaboxadol HCl (THIP) or muscimol, both gamma-aminobutyric acid (GABA) type A agonists, with indirect-acting dopamine agonists (DAGs) methylphenidate, (+)-amphetamine, metamphetamine, amfonelic acid, indatraline, nomifensine, diclofensine, mazindol, and GBR 12935 and with direct-acting DAGs WIN 35,428, bupropion, GBR 12909, and cocaine. 1,832 male C57BL/6J mice were given either with saline or 1 of the doses of THIP or muscimol before an injection of a dopamine agonist. Gnawing on corrugated packing paper was measured. Results showed that: (1) indirect- but not direct-acting DAGs induced gnawing, (2) gnawing induced by indirect-acting DAGs GBR 12935, nomifensine and mazindol was potentiated in mice in which GABA type A receptors were stimulated either by THIP or muscimol, and (3) indirect DAGs had a differential sensitivity to the effects of THIP and muscimol. ((c) 1998 APA/PsycINFO, all rights reserved) [less ▲]

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See detailgamma-Glutamylpeptides from Rhynchosia albiflora.
Wathelet, Bernard ULg; Marlier, M.; Dardenne, G. et al

in Phytochemistry (1988), 27(2),

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See detailGamma-glutamylphenylalanine in Dolichos seeds
Dardenne, G. A.; Thonart, Philippe ULg

in Phytochemistry (1973), 12

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See detailGamma-probe-directed lymphatic mapping and sentinel lymphadenectomy in primary cutaneous melanoma.
Belhocine, T.; Pierard, Gérald ULg; Gielen, Jean-Louis ULg et al

in Dermatology : International Journal for Clinical & Investigative Dermatology (2002), 204(4), 355-61

BACKGROUND: Radiotracer and blue-dye lymphatic mapping is a recommended combined method to guide sentinel lymphadenectomy and full regional lymph node dissection in selected patients with cutaneous ... [more ▼]

BACKGROUND: Radiotracer and blue-dye lymphatic mapping is a recommended combined method to guide sentinel lymphadenectomy and full regional lymph node dissection in selected patients with cutaneous melanoma. OBJECTIVE: To evaluate the diagnostic accuracy and the prognostic value of gamma-probe-directed lymphatic mapping in cutaneous melanomas. METHODS: Sixty-five stage I and II melanoma patients underwent gamma-probe-directed lymphatic mapping. Sentinel lymph nodes were studied by both conventional and immunohistochemical stainings. The median follow-up was 11 months. RESULTS: Sensitivities of preoperative and intraoperative sentinel lymph node detection were 100 and 98%, respectively. Only 1 failure of detection and 1 missed same-basin metastasis were experienced in the axillary and cervical areas, respectively. Eleven patients (16.9%) had sentinel node metastases leading to adjuvant therapy. CONCLUSION: Gamma-probe-directed lymphatic mapping is useful for staging melanoma. However, in the expectation of a more specific identification of the sentinel lymph node, the standard protocol remains recommended for exploring the axillary and cervical areas. The histological examination supported in some cases by immunohistochemistry remains mandatory in all cases. [less ▲]

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See detailGamma-ray attenuation for characterization of future space launcher fuels
Carapelle, Alain ULg; Collette, Jean-Pierre ULg

in IEEE Transactions on Nuclear Science (2006), 53(4, Part 1), 2023-2026

Gamma-ray attenuation is used to measure cryogenic mixture density. Parameters are optimized for specific space application. A simple error formula is established. The feasibility of the measurement is ... [more ▼]

Gamma-ray attenuation is used to measure cryogenic mixture density. Parameters are optimized for specific space application. A simple error formula is established. The feasibility of the measurement is demonstrated. The effect of container's walls is measured. An automatic measurement device is built. A theoretical calculation is made for the geometry of Ariane V launcher. [less ▲]

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See detailGamma-ray attenuation for measuring cryogenic slush mixture density
Carapelle, Alain ULg; Collette, Jean-Pierre ULg

in Nuclear Instruments & Methods in Physics Research. Section B, Beam Interactions with Materials and Atoms (2005), 229(1), 111-116

Gamma-ray attenuation is used to measure cryogenic mixture density. Parameters are optimized for specific space application. A simple error formula is established. The feasibility of the measurement is ... [more ▼]

Gamma-ray attenuation is used to measure cryogenic mixture density. Parameters are optimized for specific space application. A simple error formula is established. The feasibility of the measurement is demonstrated. An automatic measurement device is built. (C) 2004 Elsevier B.V. All rights reserved. [less ▲]

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See detailGamma-ray induced cascades and magnetic fields in the intergalactic medium
Elyiv, Andrii ULg; Neronov, A.; Semikoz, D. V.

in Physical Review. D : Particles and Fields (2009), 80

We present the results of Monte Carlo simulations of three-dimensional electromagnetic cascade initiated by interactions of the multi-TeV γ rays with the cosmological infrared/optical photon background in ... [more ▼]

We present the results of Monte Carlo simulations of three-dimensional electromagnetic cascade initiated by interactions of the multi-TeV γ rays with the cosmological infrared/optical photon background in the intergalactic medium. Secondary electrons in the cascade are deflected by the intergalactic magnetic fields before they scatter on CMB photons. This leads to extended 0.1°-10° scale emission at multi-GeV and TeV energies around extragalactic sources of very high-energy γ rays. The morphology of the extended emission depends, in general, on the properties of magnetic fields in the intergalactic medium. Using Monte Carlo simulated data sets, we demonstrate that the decrease of the size of extended source with the increase of energy allows to measure weak magnetic fields with magnitudes in the range from ≤10[SUP]-16[/SUP]G to 10[SUP]-12[/SUP]G if they exist in the voids of the large scale structure. [less ▲]

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See detailGamma-Ray Spectrometry: Experimental Measurement and Monte Carlo Simulation using GEANT4 toolkit
Guembou Shouop, Cébastien Joel ULg; Ndontchueng Moyo, Maurice; Chene, Grégoire ULg et al

Poster (2016, July 13)

Nowadays the precision in the measurement has become a challenge for physicists. That is why in recent decades, the interest is very granted to simulation. Since 1940, the method Monte Carlo is more ... [more ▼]

Nowadays the precision in the measurement has become a challenge for physicists. That is why in recent decades, the interest is very granted to simulation. Since 1940, the method Monte Carlo is more useful for validation and even for prediction of the results of the experiment. The aim of this study is to validate experimental models. Our laboratories are equipped with HPGe gamma spectrometers for measuring the natural radioactivity, it becomes interesting to compare and even to improve the performance of our system. Geant4 is used for the construction of the geometry of detection, the physics processes and the primary particles. First and prliminary result was prsented in this paper. [less ▲]

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See detailA gammaherpesvirus infection protects against allergic asthma.
Machiels, Bénédicte ULg; Dourcy, Mickael ULg; Sabatel, Catherine ULg et al

Poster (2014, December 12)

The “hygiene hypothesis” proposes that the augmentation of allergic diseases in developed countries could be linked to a reduced exposure to infections during childhood. Surprisingly, the potential ... [more ▼]

The “hygiene hypothesis” proposes that the augmentation of allergic diseases in developed countries could be linked to a reduced exposure to infections during childhood. Surprisingly, the potential protective role of herpesvirus infections against allergy development has never been addressed directly. In this study, we used the Murid herpesvirus 4 (MuHV-4) to study the impact of a persistent gammaherpesvirus infection on the development of House Dust Mites (HDM)-induced allergic asthma. Our results revealed that MuHV-4 infection affects both the sensitization and the challenging phases of HDM-induced airway allergy. In particular, we highlighted that MuHV-4 infection strongly impacts the lung innate immune response. Indeed, while the dendritic cells remained competent to uptake antigens and to migrate to the draining lymph nodes, MuHV-4 infection impaired their ability to trigger HDM sensitization. In the future, these results could allow us to develop strategies to prevent the development of TH2-skewed responses against respiratory allergens. [less ▲]

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See detailgammaMAXT: a fast multiple-testing correction algorithm
Van Lishout, François ULg; Gadaleta, Francesco; Moore, Jason H. et al

in BioData Mining (2015), 8(36),

Background: The purpose of the maxT algorithm is to provide a significance test algorithm that controls the family-wise error rate (FWER) during simultaneous hypothesis testing. However, the requirements ... [more ▼]

Background: The purpose of the maxT algorithm is to provide a significance test algorithm that controls the family-wise error rate (FWER) during simultaneous hypothesis testing. However, the requirements in terms of computing time and memory of this procedure are proportional to the number of investigated hypotheses. The memory issue has been solved in 2013 by Van Lishout’s implementation of MaxT, which makes the memory usage independent from the size of the dataset. This algorithm is implemented in MBMDR-3.0.3, a software that is able to identify genetic interactions, for a variety of SNP-SNP based epistasis models effectively. On the other hand, that implementation turned out to be less suitable for genome-wide interaction analysis studies, due to the prohibitive computational burden. Results: In this work we introduce gammaMAXT, a novel implementation of the maxT algorithm for multiple testing correction. The algorithm was implemented in software MBMDR-4.2.2, as part of the MB-MDR framework to screen for SNP-SNP, SNP-environment or SNP-SNP-environment interactions at a genome-wide level. We show that, in the absence of interaction effects, test-statistics produced by the MB-MDR methodology follow a mixture distribution with a point mass at zero and a shifted gamma distribution for the top 10 % of the strictly positive values. We show that the gammaMAXT algorithm has a power comparable to MaxT and maintains FWER, but requires less computational resources and time. We analyze a dataset composed of 106 SNPs and 1000 individuals within one day on a 256-core computer cluster. The same analysis would take about 104 times longer with MBMDR-3.0.3. Conclusions: These results are promising for future GWAIs.However, the proposed gammaMAXT algorithm offers a general significance assessment and multiple testing approach, applicable to any context that requires performing hundreds of thousands of tests. It offers new perspectives for fast and efficient permutation-based significance assessment in large-scale (integrated) omics studies. [less ▲]

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