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See detailEnhanced pinning in superconducting thin films with graded pinning landscapes
Motta, M.; Colauto, F.; Ortiz, W.A. et al

in Applied Physics Letters (2013), 102

A graded distribution of antidots in superconducting a-Mo79Ge21 thin films has been investigated by magnetization and magneto-optical imaging measurements. The pinning landscape has maximum density at the ... [more ▼]

A graded distribution of antidots in superconducting a-Mo79Ge21 thin films has been investigated by magnetization and magneto-optical imaging measurements. The pinning landscape has maximum density at the sample border, decreasing linearly towards the center. Its overall performance is noticeably superior than that for a sample with uniformly distributed antidots: For high temperatures and low fields, the critical current is enhanced, whereas the region of thermomagnetic instabilities in the field-temperature diagram is significantly suppressed. These findings confirm the relevance of graded landscapes on the enhancement of pinning efficiency, as recently predicted by Misko and Nori [Phys. Rev. B 85, 184506 (2012)]. [less ▲]

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See detailEnhanced Platelet Reactivity to Collagen and Shear Stress in Transgenic Mice Overexpressing the Platelet P2X1 Ion Channel
Oury, Cécile ULiege; Kuijpers, Marijke; Toth-Zsamboki, Emese et al

in Blood (2002), 100

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See detailAn enhanced process for the production of a highly purified extracellular lipase in the non-conventional yeast Yarrowia lipolytica
Turki, S.; Ayed, A.; Chalghoumi, N. et al

in Applied Biochemistry and Biotechnology (2010), 160(5), 1371-1385

Yarrowia lipolytica LgX64.81 is a non-genetically modified mutant that was previously identified as a promising microorganism for extracellular lipase production. In this work, the development of a fed ... [more ▼]

Yarrowia lipolytica LgX64.81 is a non-genetically modified mutant that was previously identified as a promising microorganism for extracellular lipase production. In this work, the development of a fed-batch process for the production of this enzyme in this strain was described. A lipolytic activity of 2,145 U/mL was obtained after 32 h of batch culture in a defined medium supplemented with 10 g/L of tryptone, an enhancer of lipase expression. To maximize the volumetric productivity, two different fed-batch strategies had been investigated. In comparison to batch process, the intermittent fed-batch strategy had not improved the volumetric lipase productivity. In contrast, the stepwise feeding strategy combined with uncoupled cell growth and lipase production phases resulted in a 2-fold increase in the volumetric lipase productivity, namely, the lipase activity reached 10,000 U/mL after 80 h of culture. Furthermore, this lipase was purified to homogeneity by anion exchange chromatography on MonoQ resin followed by gel filtration on Sephacryl S-100. This process resulted in an overall yield of 72% and a 3.5-fold increase of the specific lipase activity. The developed process offers a great potential for an economic production of Lip2 at large scale in Y. lipolytica LgX64.81. © 2009 Humana Press. [less ▲]

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See detailEnhanced proof strength after cold process of fabrication of non-linear metallic profiles – Comparison of two predictive models for hollow sections
Rossi, Barbara ULiege; Jaspart, Jean-Pierre ULiege

in International Symposium on Tubular Structures : ISTS13, Hong Kong, 15-17 December 2010 (2010)

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See detailEnhanced Release of Plasminogen Activator Inhibitor(S) but Not of Plasminogen Activators by Cultured Rat Glial Cells Treated with Interleukin-1
Rogister, Bernard ULiege; Leprince, Pierre ULiege; Delree, P. et al

in Glia (1990), 3(4), 252-7

Astroglial cells are known to proliferate during development of the nervous system, as well as during post-traumatic gliosis. We have previously shown that the proliferation of cultured astrocytes can be ... [more ▼]

Astroglial cells are known to proliferate during development of the nervous system, as well as during post-traumatic gliosis. We have previously shown that the proliferation of cultured astrocytes can be stimulated by the urokinase-type (uPA) of plasminogen activator (PA) and that astrocytes are able to release such uPA upon stimulation with basic fibroblast growth factor, which is known to act as a mitogen for these cells. Here we report studies on the effects of human interleukin-1 (IL-1) on the release of PA activity by cultured newborn rat astroglial cells. Whereas there is controversy in the literature as to whether IL-1 stimulates multiplication of astroglial cells, we failed to observe such an effect in our system. We did observe, however, a dose-dependent decrease in PA activity in the supernatant of the IL-1 treated cultures. Further analysis revealed that this apparent decrease in PA release was in fact due to an increased release of plasminogen activator inhibitor (PAI). A similar IL-1 induced increase in PAI release was also found to occur in cultures of transformed astrocytes (human glioma LN18) and in cultured Schwann cells, but not in cultures of neurons or neuronal tumour cells. Since protease inhibitors are known to possess neuritogenic properties, our results suggest that IL-1, by its capacity to induce PAI, may promote neuritogenesis. [less ▲]

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See detailEnhanced selectivity and search speed for method development using one-segment-per-component optimization strategies
Tyteca, Eva ULiege; Vanderlinden, K.; Favier, M. et al

in Journal of Chromatography. A (2014), 1358

Linear gradient programs are very frequently used in reversed phase liquid chromatography to enhance the selectivity compared to isocratic separations. Multi-linear gradient programs on the other hand are ... [more ▼]

Linear gradient programs are very frequently used in reversed phase liquid chromatography to enhance the selectivity compared to isocratic separations. Multi-linear gradient programs on the other hand are only scarcely used, despite their intrinsically larger separation power. Because the gradient-conformity of the latest generation of instruments has greatly improved, a renewed interest in more complex multi-segment gradient liquid chromatography can be expected in the future, raising the need for better performing gradient design algorithms. We explored the possibilities of a new type of multi-segment gradient optimization algorithm, the so-called "one-segment-per-group-of-components" optimization strategy. In this gradient design strategy, the slope is adjusted after the elution of each individual component of the sample, letting the retention properties of the different analytes auto-guide the course of the gradient profile. Applying this method experimentally to four randomly selected test samples, the separation time could on average be reduced with about 40% compared to the best single linear gradient. Moreover, the newly proposed approach performed equally well or better than the multi-segment optimization mode of a commercial software package. Carrying out an extensive in silico study, the experimentally observed advantage could also be generalized over a statistically significant amount of different 10 and 20 component samples. In addition, the newly proposed gradient optimization approach enables much faster searches than the traditional multi-step gradient design methods. © 2014 Elsevier B.V. [less ▲]

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See detailEnhanced silicate weathering of tropical shelf sediments exposed during glacial lowstands: a sink for atmospheric CO2
Wan, Shiming; Clift, Peter D.; Zhao, Debo et al

in Geochimica et Cosmochimica Acta (2017), 200

Atmospheric CO2 and global climate are closely coupled. Since 800 ka CO2 concentrations have been up to 50% higher during interglacial compared to glacial periods. Because of its dependence on temperature ... [more ▼]

Atmospheric CO2 and global climate are closely coupled. Since 800 ka CO2 concentrations have been up to 50% higher during interglacial compared to glacial periods. Because of its dependence on temperature, humidity, and erosion rates, chemical weathering of exposed silicate minerals was suggested to have dampened these cyclic variations of atmospheric composition. Cooler and drier conditions and lower non-glacial erosion rates suppressed in situ chemical weathering rates during glacial periods. However, using systematic variations in major element geochemistry, Sr-Nd isotopes and clay mineral records from Ocean Drilling Program Sites 1143 and 1144 in the South China Sea spanning the last 1.1 Ma, we show that sediment deposited during glacial periods was more weathered than sediment delivered during interglacials. We attribute this to subaerial exposure and weathering of unconsolidated shelf sediments during glacial sealevel lowstands. Our estimates suggest that enhanced silicate weathering of tropical shelf sediments exposed during glacial lowstands can account for ~9% of the carbon dioxide removed from the atmosphere during the glacial and thus represent a significant part of the observed glacial-interglacial variation of ~80 ppmv. As a result, if similar magnitudes can be identified in other tropical shelf-slope systems, the effects of increased sediment exposure and subsequent silicate weathering during lowstands could have potentially enhanced the drawdown of atmospheric CO2 during cold stages of the Quaternary. This in turn would have caused an intensification of glacial cycles. We attribute this to subaerial exposure and weathering of unconsolidated shelf sediments during glacial sealevel lowstands. Our estimates suggest that enhanced silicate weathering of tropical shelf sediments exposed during glacial lowstands can account for ~9% of the carbon dioxide removed from the atmosphere during the glacial and thus represent a significant part of the observed glacial-interglacial variation of ~80 ppmv. As a result, if similar magnitudes can be identified in other tropical shelf-slope systems, the effects of increased sediment exposure and subsequent silicate weathering during lowstands could have potentially enhanced the drawdown of atmospheric CO2 during cold stages of the Quaternary. This in turn would have caused an intensification of glacial cycles. [less ▲]

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See detailEnhanced sludge dewatering and drying comparison of two linear polyelectrolytes co-conditioning with Polyaluminium chloride
Pambou, Yvon-Bert ULiege; Fraikin, Laurent ULiege; Salmon, Thierry ULiege et al

Poster (2014, May 26)

Annual production of sewage sludge in Europe is estimated at more than eleven million tons of dry matter content [1]. Use in agriculture and incineration are the main ways of valorization. In this context ... [more ▼]

Annual production of sewage sludge in Europe is estimated at more than eleven million tons of dry matter content [1]. Use in agriculture and incineration are the main ways of valorization. In this context, drying of residual sludge appears as an essential step after mechanical dewatering. It reduces the costs of storage, transport and allows the sludge stabilization. However, this process is highly energy consuming and still needs to be optimized as it constitutes an important economic and environmental issue [2]. Polymers are usually employed in the conditioning step in order to promote particle aggregation, making the dewatering easier. The past decades, the application of pre-hydrolized polyaluminium chlorides (PACls) as coagulant has increased, particularly in China, Japan, Russia and Western Europe [3]. As a consequence, PACls are extensively investigated for their coagulation performance, characterization and speciation [3]. In this work, the influence of Polyaluminium chloride (PAX-14) co-conditioning with linear polyelectrolytes on sludge dewatering and drying performances was investigated. Experiments were conducted on activated sludge samples collected after thickening from the wastewater treatment plant of the Grosses- Battes (Belgium). Two cationic polymers were tested, each of them in combination with PAX for sludge flocculation prior to mechanical dewatering and their effects on sludge convective drying. The one referenced as 640 LH was a linear polymer with a low molecular weight, whereas the 640 CT was a linear one with a high molecular weight. After conditioning, the dewatering step was realized by using a normalized filtration-expression cell (AFNOR 1979) under 5 bar of pressure. Then, the specific resistance to filtration was determined from the follow-up of filtrate mass with time, using the Carman-Kozeny equation [4]. Figure 1 shows the experimental design. For convective drying experiments, the cake recovered after filtration was extruded through a circular die of 14 mm diameter and cut at a height of 14 mm, yielding cylindrical samples with mass of approximately 2.5 g, as used in several industrial belt dryers. Individual extrudates have been dried in a specially designed convective micro-dryer. Results reported in this paper were obtained with the following operating conditions: air temperature of 130 °C, at ambient humidity (absolute humidity ~ 0.005 kgwater/ kgdry air) and a superficial velocity of 1 m/ s. Results show that, the dry solids content of the dewatering cake increases with increasing Polyaluminium chloride dosage for both series of experiments. It supposes that PAX contributed to improve solids capture, depicted on Fig. 2. Concerning drying, it appeared that the samples treated by the dual PAX/ polymers combination showed higher drying rates than samples conditioned by polymer without PAX addition, allowing a reduction of the drying time (see Fig. 3). Table 1 shows the drying characteristics of the samples. The drying time decreases and the average drying rate increases with the dual conditioners addition, while the initial water content decreases as well as the total amount water to be removed. [less ▲]

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See detailEnhanced sludge dewatering and drying comparison of two linear polyelectrolytes co-conditioning with Polyaluminium chloride
Pambou, Yvon-Bert ULiege; Fraikin, Laurent ULiege; Salmon, Thierry ULiege et al

Poster (2014, October 23)

Annual production of sewage sludge in Europe is estimated at more than ten million tons of dry matter. Use in agriculture and incineration are the main ways of valorization. In this context, sludge drying ... [more ▼]

Annual production of sewage sludge in Europe is estimated at more than ten million tons of dry matter. Use in agriculture and incineration are the main ways of valorization. In this context, sludge drying appears as an essential step after mechanical dewatering. It reduces the costs of storage and transport, allows the stabilization and the hygienization of sludge while increasing its calorific value. However, this process is highly energy consuming and still needs to be optimized as it constitutes an important economic and environmental issue. This implies the improvement of knowledge about sludge drying, including the impact of the mechanical dewatering step. Before studying experimentally the influence of polymers type and dosage use for dewatering on the rheological properties and the drying process, it is necessary to assess the stability of the sludge during of the storage. Because sludge is a living material that can rapidly change, we use the method of experimental design in order to get maximum information with minimal testing, regarding sludge stability during storage. [less ▲]

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See detailEnhanced stabilization of water-scCO2 interface by block-like spontaneous gradient copolymers
Liu, Xuan; Wang, Mingxi; Harrisson, Simon et al

in ACS Sustainable Chemistry & Engineering (in press)

There is an increasing interest in the specific physicochemical properties of gradient copolymers at interfaces. In this work, the phase behavior and interfacial properties of amphiphilic gradient ... [more ▼]

There is an increasing interest in the specific physicochemical properties of gradient copolymers at interfaces. In this work, the phase behavior and interfacial properties of amphiphilic gradient copolymers at the water/CO2 interface are explored and compared to that of diblock copolymer counterparts. It is observed that spontaneous amphiphilic block-like gradient copolymers made of N,N-dimethylacrylamide, vinyl pivalate, and vinyl acetate exhibit slightly lower cloud point pressures in supercritical carbon dioxide (scCO2) than the corresponding diblock copolymers. Much more pronounced differences are established at the water/scCO2 interface, with larger critical aggregation concentration (CAC), much faster adsorption kinetics and equilibration, and lower surface tension for gradient copolymers. RAFT/MADIX polymerization allows the control of molar mass, composition, and microstructure of the copolymers of the study. These findings shed light on how microstructural control in amphiphilic copolymers can give access to a new range of macromolecular emulsifiers for CO2 media with improved properties. [less ▲]

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See detailEnhanced survival of lung granulocytes in an animal model of asthma : evidence for a role of GM-CSF-activated STAT5 signaling pathway
Turlej, R.; Sandersen, Charlotte ULiege; Fievez, Laurence ULiege et al

in Proceedings: International Conference of the American Thoracic Society (2001)

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See detailEnhanced survival of lung granulocytes in an animal model of asthma: evidence for a role of GM-CSF activated STAT5 signalling pathway
Turlej, Renata K; Fievez, Laurence ULiege; Sandersen, Charlotte ULiege et al

in Thorax (2001), 56(9), 696-702

As granulocyte/macrophage colony stimulating factor (GM-CSF) mediated delay of granulocyte apoptosis contributes to the accumulation of inflammatory cells at the site of inflammation in many diseases, we ... [more ▼]

As granulocyte/macrophage colony stimulating factor (GM-CSF) mediated delay of granulocyte apoptosis contributes to the accumulation of inflammatory cells at the site of inflammation in many diseases, we sought to determine whether asthma is also associated with a GM-CSF dependent increase in lung granulocyte survival. Moreover, because GM-CSF mediates its effects through activation of signal transducer and activator of transcription 5 (STAT5), we also investigated the potential role of STAT5 in allergic inflammation. METHODS: Blood granulocytes were recovered from six healthy and six heaves affected horses, a model of asthma. Lung granulocytes were obtained by bronchoalveolar lavage (BAL) from the same horses. Granulocytes were cultured in the presence or absence of anti-GM-CSF receptor antibodies for different times and apoptosis was determined using the Annexin-V/propidium iodide detection method. Nuclear protein extracts from cultured granulocytes were analysed for STAT5 binding activity by electrophoretic mobility shift assay. RESULTS: BAL fluid granulocytes from heaves affected horses demonstrated a significant delay in apoptosis compared with blood granulocytes from the same horses and blood and BAL fluid granulocytes from healthy horses. Conversely, the rate of apoptosis in blood granulocytes from healthy and heaves affected horses was comparable. The enhanced survival of BAL fluid granulocytes from affected horses was suppressed in the presence of antibodies directed against GM-CSF receptors. Increased levels of active STAT5 were found in BAL fluid granulocytes from heaves affected horses and were markedly reduced after treatment with anti-GM-CSF receptor antibodies. CONCLUSIONS: These data indicate that granulocyte survival is enhanced in the lung of heaves affected horses and suggest a role for a GM-CSF activated STAT5 pathway in delaying apoptosis of lung granulocytes in this model of asthma. [less ▲]

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See detailEnhanced survival of lung granulocytes in an animal model of asthma: evidence for a role of GM-CSF-activated STAT5 signaling pathway
Turlej, R.; Sandersen, Charlotte ULiege; Fievez, Laurence ULiege et al

in Proceedings: World Equine Airways Symposium (2001)

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See detailEnhanced susceptibility of focal ischemic in jury in mice lacking prostacyclin receptors
Huang, Zihong; Austin, S.; Salomone, Salvatore et al

Poster (2002)

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See detailEnhanced thermoelectric performance in spark plasma textured bulk n-type BiTe2.7Se0.3 and p-type Bi0.5Sb 1.5Te3
Bhame, S. D.; Dhanapal, Pravarthana ULiege; Prellier, W. et al

in Applied Physics Letters (2013), 102

Bulk p and n-type bismuth tellurides were prepared using spark plasma texturization method. The texture development along the uniaxial load in the 001 direction is confirmed from both x-ray diffraction ... [more ▼]

Bulk p and n-type bismuth tellurides were prepared using spark plasma texturization method. The texture development along the uniaxial load in the 001 direction is confirmed from both x-ray diffraction analysis and electron backscattering diffraction measurements. Interestingly, those textured samples outperform the samples prepared by conventional spark plasma sintering (SPS) leading to a reduced thermal conductivity in the ab-plane. The textured samples of n-type BiTe2.7Se0.3 and p-type Bi0.5Sb 1.5Te3 showed a 42% and 33% enhancement in figure of merit at room temperature, respectively, as compared to their SPS counterparts, opening the route for applications. © 2013 AIP Publishing LLC. [less ▲]

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See detailEnhanced tropospheric HCN columns above Kitt Peak during the 1982-1983 and 1997-1998 El Nino warm phases
Rinsland, Curtis P.; Goldman, Aaron; Zander, Rodolphe ULiege et al

in Journal of Quantitative Spectroscopy & Radiative Transfer (2001), 69(1), 3-8

Free tropospheric HCN columns have been derived from infrared solar spectra recorded with the National Solar Observatory Fourier transform spectrometer on Kitt Peak, Arizona (31.9ºN latitude, 111.6ºW ... [more ▼]

Free tropospheric HCN columns have been derived from infrared solar spectra recorded with the National Solar Observatory Fourier transform spectrometer on Kitt Peak, Arizona (31.9ºN latitude, 111.6ºW longitude, 2.09 km altitude) between May 1978 and May 2000. The time series show up to a factor of 2.4 enhancement during the strong El Ninos of 1982-1983 and 1997-1998, the most intense since 1970. The observations provide confirmation that HCN is a sensitive tracer of biomass burning emissions transported to the free troposphere. No statistically significant long-term trend in the HCN-free tropospheric column has been detected over the 22-year measurement period. The results illustrate the importance of long-term spectroscopic measurements for quantifying climate and atmospheric chemistry-related atmospheric changes. [less ▲]

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See detailEnhanced urinary odor discrimination in female aromatase knockout (ArKO) mice
Wesson, D. W.; Keller, Matthieu ULiege; Douhard, Quentin ULiege et al

in Hormones & Behavior (2006), 49(5), 580-586

We asked whether odor discrimination abilities are sexually dimorphic in mice and, if so, whether the perinatal actions of estradiol contribute to these sex differences. The ability to discriminate ... [more ▼]

We asked whether odor discrimination abilities are sexually dimorphic in mice and, if so, whether the perinatal actions of estradiol contribute to these sex differences. The ability to discriminate different types of urinary odors was compared in male and female wild-type (WT) subjects and in mice with a hornozygous-null mutation of the estrogen synthetic enzyme, aromatase (aromatase knockout; ArKO). Olfactory discrimination was assessed in WT and ArKO male and female mice after they were gonadectomized in adulthood and subsequently treated with estradiol benzoate. A liquid olfactometer was used to assess food-motivated olfactory discrimination capacity. All animals eventually learned to distinguish between urinary odors collected from gonadally intact males and estrous females; however, WT males as well as ArKO mice of both sexes learned this discrimination significantly more rapidly than WT females. Similar group differences were obtained when mice discriminated between urinary odors collected from gonadally intact vs. castrated males or between two non-social odorants, amyl and butyl acetate. When subjects had to discriminate volatile urinary odors from ovariectomized female mice treated with estradiol sequenced with progesterone versus estradiol alone, ArKO females quickly acquired the task whereas WT males and females as well as ArKO males failed to do so. These results demonstrated a strong sex dimorphism in olfactory discrimination ability, with WT males performing better than females. Furthermore, female ArKO mice showed an enhanced ability to discriminate very similar utinary odorants, perhaps due to an increased sensitivity of the main olfactory nervous system to adult estradiol treatment as a result perinatal estrogen deprivation. (c) 2005 Elsevier Inc. All rights reserved. [less ▲]

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