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See detailHeterogeneity of multitasking abilities in schizophrenia.
Laloyaux, Julien ULiege; Van der Linden, Martial ULiege; Laroi, Frank ULiege

in Van Overwalle, Frank; Uzieblo, Kasia; Rossi, Gina (Eds.) et al Abstract book of the Annual meeting of the Belgian Association for Psychological Sciences (2015)

Difficulties in everyday life activities are core features of persons diagnosed with schizophrenia, and in particular for those activities requiring multitasking capacities. Multitasking refers to ... [more ▼]

Difficulties in everyday life activities are core features of persons diagnosed with schizophrenia, and in particular for those activities requiring multitasking capacities. Multitasking refers to activities (e.g. preparing a meal) where the person has to: (a) carry out and alternate between different tasks that vary in terms of priority, difficulty and duration; (b) define the tasks’ targets; (c) and face unexpected problems during the realization of these tasks. Moreover, schizophrenia is characterized by a great heterogeneity in regard to their everyday life difficulties and cognitive functioning. At present, patients’ multitasking capacities have not been adequately examined in the literature due to an absence of suitable assessment strategies. We thus recently developed a computerized real-life activity task designed to take into account the complex and multitasking nature of certain everyday life activities where participants are required to prepare a room for a meeting (i.e. the Computerized Meeting Preparation Task, CMPT). The aim of this study was to examine the multitasking abilities in persons diagnosed with schizophrenia and in particular the existence of subgroups of patients in regard to their performances on cognitive measures and on the CMPT. Sixty-two patients diagnosed with schizophrenia and 39 paired healthy controls completed the CMPT and a cognitive battery. The results reveal that the CMPT possesses good sensitivity and suggest three underlying constructs of multitasking (Memory, Planning and Intent), which were found to be underpinned by several cognitive functions and multitasking aspects. Moreover, cluster analyses revealed subgroups of patients differing in terms of their cognitive and CMPT performances. Taken together, these results show the need for a cognitive model of multitasking abilities in persons diagnosed with schiozphrenia. Taken together, this cognitive model and the CMPT, could be a good basis for cognitive interventions of multitasking abilities in schizophrenia. Finally, the results underline the heterogeneity of schizophrenia. [less ▲]

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See detailHeterogeneity of phenotypes in severe asthmatics. The Belgian Severe Asthma Registry (BSAR).
SCHLEICH, FLorence ULiege; Brusselle, G.; Louis, Renaud ULiege et al

in Respiratory medicine (2014), 108(12), 1723-32

The Belgian severe asthma registry is a web-based registry encompassing demographic, clinical, functional and inflammatory data of severe asthmatics (SA), aiming at improving awareness, knowledge on its ... [more ▼]

The Belgian severe asthma registry is a web-based registry encompassing demographic, clinical, functional and inflammatory data of severe asthmatics (SA), aiming at improving awareness, knowledge on its natural history and subphenotypes, and offering tools to optimize care of this asthma population. METHODS: The cross-sectional analyses of this registry included 350 SA as defined by the ATS (2000) from 9 Belgian centres, with at least one year follow up. RESULTS: Mean age was 55 +/- 14 yrs. SA were more frequently female (57%) and atopic (70%). Late-onset asthma (>/=40 yr) was observed in 31% of SA. Current smokers represented 12% while 31% were ex-smokers. In addition to high doses ICS + LABA, 65% of patients were receiving LTRA, 27% anti-IgE and 24% maintenance oral corticosteroids (8 mg (Interquartile range-IQR:4-8) methylprednisolone). Despite impaired airflow (median FEV1:67%; IQR: 52-81) only 65% had a post-bronchodilator FEV1/FVC ratio <70%. The median blood eosinophil count was 240/mm(3). The median FENO was 26 ppb (IQR: 15-43) and 22% of SA had FENO >/= 50 ppb. Induced sputum was successful in 86 patients. Eosinophilic asthma (sputum Eos >/= 3%) was the predominant phenotype (55%) while neutrophilic (sputum Neu >/= 76%) and paucigranulocytic asthma accounted for 22% and 17% respectively. Comorbidities included rhinitis and chronic rhinosinusitis (49%), nasal polyposis (19%), oesophageal reflux (36%), overweight and obesity (47%) and depression (19%). In addition, 8% had aspirin-induced asthma and 3% ABPA. Asthma was not well-controlled in 83% according to ACT < 20 and 77% with ACQ > 1.5. CONCLUSION: In this cohort of patients with severe asthma, the majority displayed indices of persistent airflow limitation and eosinophilic inflammation despite high-dose corticosteroids, suggesting potential for eosinophil-targeted biotherapies. [less ▲]

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See detailHeterogeneity of residuals variances of milk fatty acids in dairy cattle
Arnould, Valérie ULiege; Soyeurt, Hélène ULiege; Vanderick, Sylvie ULiege et al

in Journal of Dairy Science (2010, July), 88(E-Suppl. 2), 744

Routine genetic evaluation for milk fatty acids is under development in the Walloon Region of Belgium. The objective of this study was to test the heterogeneity of residual variances and therefore ... [more ▼]

Routine genetic evaluation for milk fatty acids is under development in the Walloon Region of Belgium. The objective of this study was to test the heterogeneity of residual variances and therefore indirectly the potential need to adjust for this heterogeneity if it exists. The residuals were computed as the difference between the observed and the estimated values using a multi-trait random regression test-day model, similar to the Walloon routine model, used for first lactation only milk yield, quantities and percentages of protein (PROT) and fat (FAT), content of saturated fatty acids in milk (g/100g of milk, SAT) and, content of mono-unsaturated fatty acids in milk (g/100g of milk, MONO). Residuals were considered homogeneous inside strata defined, among others, by weeks of lactation, by days in milk and by calendar months of test date. About 6,687,000 records were available for milk yield and for FAT and PROT parameters. For SAT and for MONO, about 184,000 records were available in this database. Means of residuals were stable and close to zero for all traits. Variances were more variable for MONO and SAT than for milk yield, for example. Daily and weekly variances tended to decrease at the end of the lactation (50%). When the variances were computed by month of test date, some variations were observed and some periods of year were more marked. In conclusion, the observed residual variances were less stable for MONO and SAT. We can conclude that introduction for heterogeneous residual variance is more important for the new traits (MONO, SAT) than it was for the old, traditional ones. [less ▲]

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See detailHeterogeneity of residuals variances of milk fatty acids in dairy cattle
Arnould, Valérie ULiege; Soyeurt, Hélène ULiege; Vanderick, Sylvie ULiege et al

Conference (2010, July)

Routine genetic evaluation for milk fatty acids is under development in the Walloon Region of Belgium. The objective of this study was to test the heterogeneity of residual variances and therefore ... [more ▼]

Routine genetic evaluation for milk fatty acids is under development in the Walloon Region of Belgium. The objective of this study was to test the heterogeneity of residual variances and therefore indirectly the potential need to adjust for this heterogeneity if it exists. The residuals were computed as the difference between the observed and the estimated values using a multi-trait random regression test-day model, similar to the Walloon routine model, used for first lactation only milk yield, quantities and percentages of protein (PROT) and fat (FAT), content of saturated fatty acids in milk (g/100g of milk, SAT) and, content of mono-unsaturated fatty acids in milk (g/100g of milk, MONO). Residuals were considered homogeneous inside strata defined, among others, by weeks of lactation, by days in milk and by calendar months of test date. About 6,687,000 records were available for milk yield and for FAT and PROT parameters. For SAT and for MONO, about 184,000 records were available in this database. Means of residuals were stable and close to zero for all traits. Variances were more variable for MONO and SAT than for milk yield, for example. Daily and weekly variances tended to decrease at the end of the lactation (50%). When the variances were computed by month of test date, some variations were observed and some periods of year were more marked. In conclusion, the observed residual variances were less stable for MONO and SAT. We can conclude that introduction for heterogeneous residual variance is more important for the new traits (MONO, SAT) than it was for the old, traditional ones. [less ▲]

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See detailHeterogeneity of sponastrime dysplasia: Delineation of a variant form with severe mental retardation
Verloes, Alain ULiege; Misson, Jean-Paul ULiege; Dubru, J. M. et al

in Clinical Dysmorphology (1995), 4(3), 208-215

We report a child with short stature, osteopenia with metaphyseal striations and severe mental retardation. This child shows radiological and clinical features of SPONASTRIME dysplasia. Only three ... [more ▼]

We report a child with short stature, osteopenia with metaphyseal striations and severe mental retardation. This child shows radiological and clinical features of SPONASTRIME dysplasia. Only three sibships with this disorder have been reported. In two families, affected patients were of normal intelligence. In the third one, as well as our case, the dysplasia was complicated by severe mental retardation of unknown origin. The severity of the retardation in our case and a previous report, and some difference in the gestalt and radiological aspects, suggest that SPONASTRIME dysplasia is a heterogeneous disorder. We provisionally propose to split SPONASTRIME dysplasia in two phenotypically distinct subgroups, and to delineate here a 'new' variant with microcephaly and severe mental impairment. [less ▲]

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See detailHeterogeneity of systemic oxidative stress profiles in COPD : a potential role of gender
Maury, Jonathan; Gouzi, Fares; De Rigal, Philippe et al

in Oxidative Medicine and Cellular Longevity (2015)

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See detailHeterogeneity of the eae Genes in Attaching/Effacing Escherichia Coli from Cattle: Comparison with Human Strains
China, B.; Jacquemin, E.; Devrin, A. C. et al

in Research in Microbiology (1999), 150(5), 323-332

Enteropathogenic (EPEC) and enterohaemorrhagic (EHEC) Escherichia coli isolated from cattle were studied by DNA colony hybridization to subtype their intimin-encoding (eae) gene with probes derived from ... [more ▼]

Enteropathogenic (EPEC) and enterohaemorrhagic (EHEC) Escherichia coli isolated from cattle were studied by DNA colony hybridization to subtype their intimin-encoding (eae) gene with probes derived from the variable parts of the eae alpha gene of the human EPEC strain E2348/69, the eae gamma gene of the human O157:H7 EHEC strain ATCC43888, and the eae beta gene of the bovine O26:H- EHEC strain 193, whose eae gene was first cloned and sequenced during this work. The EPEC and EHEC had been isolated from diarrhoeic calves (143 EPEC and 48 EHEC) and from healthy animals at the slaughterhouse (10 EPEC and 34 EHEC). The 191 bovine EPEC and EHEC isolated from diseased calves were positive with the Eae beta probe (55 and 27% respectively) and with the Eae gamma probe (9 and 73% respectively), whereas 52 EPEC (36%) were negative with the Eae alpha, Eae beta, and Eae gamma probes. The results were different for the 44 bovine EPEC and EHEC isolated from healthy cattle at slaughterhouses: most tested positive with the Eae gamma probe (80 and 82% respectively) and the remaining (20 and 18% respectively) with the Eae beta probe. Nine O26 human EHEC tested positive with the Eae beta probe and seven O111 with the Eae gamma probe. The bovine and human EPEC and EHEC belonging to these two serogroups gave identical results: the 18 bovine and human O26 isolates tested positive with the Eae beta probe, whereas the 13 O111 isolates were positive with the Eae gamma probe. In contrast, the isolates belonging to other serogroups (O5, O15, O18, O20, and O118) gave more variable results. The eae beta and eae gamma, but not the eae alpha, variants were thus distributed amongst bovine EPEC and EHEC. The eae beta variant seemed to be more frequently associated with the presence of clinical signs in calves, but one third of EPEC from diarrhoeic calves carried an eae gene variant other than the alpha, beta, or gamma variants. In addition, the use of these gene probes did not enable differentiation between bovine and human EHEC belonging to the same O serogroup. [less ▲]

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See detailThe heterogeneity of the left dorsal premotor cortex evidenced by multimodal connectivity-based parcellation and functional characterization
Genon, Sarah ULiege; Reid, Andrew; Li, Hai et al

in NeuroImage (in press)

Despite the common conception of the dorsal premotor cortex (PMd) as a single brain region, its diverse connectivity profiles and behavioral heterogeneity argue for a differentiated organization of the ... [more ▼]

Despite the common conception of the dorsal premotor cortex (PMd) as a single brain region, its diverse connectivity profiles and behavioral heterogeneity argue for a differentiated organization of the PMd. A previous study revealed that the right PMd is characterized by a rostro-caudal and a ventro-dorsal distinction dividing it into five subregions: rostral, central, caudal, ventral and dorsal. The present study assessed whether a similar organization is present in the left hemisphere, by capitalizing on a multimodal data-driven approach combining connectivity-based parcellation (CBP) based on meta-analytic modeling, resting- state functional connectivity, and probabilistic diffusion tractography. The resulting PMd modules were then characterized based on multimodal functional connectivity and a quantitative analysis of associated behavioral functions. Analyzing the clusters consistent across all modalities revealed an organization of the left PMd that mirrored its right counterpart to a large degree. Again, caudal, central and rostral modules reflected a cognitive- motor gradient and a premotor eye-field was found in the ventral part of the left PMd. In addition, a distinct module linked to abstract cognitive functions was observed in the rostro- ventral left PMd across all CBP modalities, implying greater differentiation of higher cognitive functions for the left than the right PMd. [less ▲]

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See detailThe heterogeneity of verbal short-term memory impairment in aphasia
Majerus, Steve ULiege; Attout, Lucie ULiege; Artielle, Marie-Amélie et al

in Neuropsychologia (2015), 77

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See detailHETEROGENEITY OF ZOOXANTHELLAE DENSITY IN THE CORAL ACROPORA GLOBICEPS AROUND MOOREA (FRENCH POLYNESIA)
Ladrière, Ophélie ULiege; van Lierde, Elodie; Penin, Lucie et al

Poster (2008)

Understanding the natural heterogeneity of coral zooxanthellae density appears as very important to understand variations in coral survival due to bleaching (the loss of these micro-algal symbionts ... [more ▼]

Understanding the natural heterogeneity of coral zooxanthellae density appears as very important to understand variations in coral survival due to bleaching (the loss of these micro-algal symbionts). Heterogeneity of coral bleaching at different observation scales (within a colony, among neighbouring colonies of the same species or on a wider scale) remains largely misunderstood. The present work explores intracolonial, spatial and temporal variations of zooxanthellae density in the coral Acropora globiceps Dana 1846, over a period of three months on the forereef of Moorea, French Polynesia. In our study, intracolonial zooxanthellae densities did not vary significantly. However, zooxanthellae densities differed slightly between inner and outer branches but this trend was not significant at 6, 12 and 18 meters depth. On a wider scale, zooxanthellae densities also vary spatially : a positive correlation was observed between depth and symbiont density (density increases when light intensity decreases, so according to depth). Moreover, the location of colonies exposed to different hydrodynamical conditions was not a parameter controling the concentration of zooxanthellae. Finally, the temporal variation of zooxanthellae densities did not show significant variations even if it decreased slightly over the study period. The results of this study highlight the importance of accounting for variations within and among colonies to determine zooxanthellae densities and to assess the evolution of zooxanthellae populations. [less ▲]

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See detailHeterogeneity of zooxanthellae density in the coral Acropora globiceps around Moorea (French Polynesia)
Ladrière, Ophélie ULiege; van Lierde, Elodie; Penin, Lucie et al

Poster (2008)

Understanding the natural heterogeneity of coral zooxanthellae density appears as very important to understand variations in coral survival due to bleaching (the loss of these micro-algal symbionts ... [more ▼]

Understanding the natural heterogeneity of coral zooxanthellae density appears as very important to understand variations in coral survival due to bleaching (the loss of these micro-algal symbionts). Heterogeneity of coral bleaching at different observation scales (within a colony, among neighbouring colonies of the same species or on a wider scale) remains largely misunderstood. The present work explores intracolonial, spatial and temporal variations of zooxanthellae density in the coral Acropora globiceps Dana 1846, over a period of three months on the forereef of Moorea, French Polynesia. In our study, intracolonial zooxanthellae densities did not vary significantly. However, zooxanthellae densities differed slightly between inner and outer branches but this trend was not significant at 6, 12 and 18 meters depth. On a wider scale, zooxanthellae densities also vary spatially : a positive correlation was observed between depth and symbiont density (density increases when light intensity decreases, so according to depth). Moreover, the location of colonies exposed to different hydrodynamical conditions was not a parameter controling the concentration of zooxanthellae. Finally, the temporal variation of zooxanthellae densities did not show significant variations even if it decreased slightly over the study period. The results of this study highlight the importance of accounting for variations within and among colonies to determine zooxanthellae densities and to assess the evolution of zooxanthellae populations. [less ▲]

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See detailHeterogeneity Reduces Sensitivity of Cell Death for TNF-Stimuli
Schliemann, Monica ULiege; Bullinger, Eric ULiege; Borchers, Steffen et al

in BMC Systems Biology (2011), 5

Background Apoptosis is a form of programmed cell death essential for the maintenance of homeostasis and the removal of potentially damaged cells in multicellular organisms. By binding its cognate ... [more ▼]

Background Apoptosis is a form of programmed cell death essential for the maintenance of homeostasis and the removal of potentially damaged cells in multicellular organisms. By binding its cognate membrane receptor, TNF receptor type 1 (TNF-R1), the proinflammatory cytokine Tumor Necrosis Factor (TNF) activates pro-apoptotic signaling via caspase activation, but at the same time also stimulates nuclear factor kappaB (NF-kappaB)-mediated survival pathways. Differential dose-response relationships of these two major TNF signaling pathways have been described experimentally and using mathematical modeling. However, the quantitative analysis of the complex interplay between pro- and anti-apoptotic signaling pathways is an open question as it is challenging for several reasons: the overall signaling network is complex, various time scales are present, and cells respond quantitatively and qualitatively in a heterogeneous manner. Results This study analyzes the complex interplay of the crosstalk of TNF-R1 induced pro- and anti-apoptotic signaling pathways based on an experimentally validated mathematical model. The mathematical model describes the temporal responses on both the single cell level as well as the level of a heterogeneous cell population, as observed in the respective quantitative experiments using TNF-R1 stimuli of different strengths and durations. Global sensitivity of the heterogeneous population was quantified by measuring the average gradient of time of death versus each population parameter. This global sensitivity analysis uncovers the concentrations of Caspase-8 and Caspase-3, and their respective inhibitors BAR and XIAP, as key elements for deciding the cell's fate. A simulated knockout of the NF-kappaB-mediated anti-apoptotic signaling reveals the importance of this pathway for delaying the time of death, reducing the death rate in the case of pulse stimulation and significantly increasing cell-to-cell variability. Conclusions Cell ensemble modeling of a heterogeneous cell population including a global sensitivity analysis presented here allowed us to illuminate the role of the different elements and parameters on apoptotic signaling. The receptors serve to transmit the external stimulus; procaspases and their inhibitors control the switching from life to death, while NF-kappaB enhances the heterogeneity of the cell population. The global sensitivity analysis of the cell population model further revealed an unexpected impact of heterogeneity, i.e. the reduction of parametric sensitivity. [less ▲]

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See detailHeterogeneity versus variability in Neuhauser megalocornea-mental retardation (MMR) syndromes: Report of new cases and delineation of 4 probable types
Verloes, Alain ULiege; Journel, H.; Elmer, C. et al

in American Journal of Medical Genetics (1993), 46(2), 132-137

Megalocornea (corneal diameter > or = 13 mm) is associated with mental and neurological impairment, and minor anomalies in Neuhauser syndrome (megalocornea-mental retardation syndrome). Here we report 4 ... [more ▼]

Megalocornea (corneal diameter > or = 13 mm) is associated with mental and neurological impairment, and minor anomalies in Neuhauser syndrome (megalocornea-mental retardation syndrome). Here we report 4 new cases of megalocornea and mental retardation. Those unrelated patients have a consistent pattern of anomalies with possible recessive inheritance which clearly differs from that of the original patients of Neuhauser et al. [1975]. We discuss the heterogeneity of the syndromes with megalocornea and mental retardation. Based on these cases and on a review of the literature, we suggest a provisional clinically oriented classification in 5 subtypes: (1) a recessive form type Neuhauser (with iris hypoplasia and minor anomalies), (2) a recessive form type Frank-Temtamy (with camptodactyly, scoliosis and growth retardation), (3) a recessive type 3, including our 4 personal cases (with normal irides, severe hypotonia, relative or absolute macrocephaly and minor anomalies), (4) a possible Frydman type (with normal irides, megalencephaly and obesity), and (5) provisionally unclassifiable cases. [less ▲]

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See detailHeterogeneous alkenylation of aromatics under oxygen
Hajek, Jan; Dams, Mieke; Detrembleur, Christophe ULiege et al

in Catalysis Communications (2007), 8(7), 1047-1051

A novel heterogeneous Pd/polymer catalyst containing co-catalytic functional groups catalyses the direct alkenylation of anisole with ethyl trans-cinnamate under oxygen. The properties of the polymeric ... [more ▼]

A novel heterogeneous Pd/polymer catalyst containing co-catalytic functional groups catalyses the direct alkenylation of anisole with ethyl trans-cinnamate under oxygen. The properties of the polymeric catalyst were compared to other immobilised catalysts. The activity of the polymeric catalyst typically increased with temperature and oxygen pressure exhibiting the optimal activity up to 100 TON at 383 K under 1.2 MPa of O-2. The most abundant product was 3-(p-methoxyphenyl)-3-phenylpropanoate (approximate to 45%). The reaction selectivity was practically independent of the conditions. Split-tests and AAS measurements confirm heterogeneous character of the catalyst. [less ▲]

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See detailHeterogeneous bedrock investigation for a closed-loop geothermal system: A case study
Radioti, Georgia ULiege; Delvoie, Simon ULiege; Charlier, Robert ULiege et al

in Geothermics (2016)

This paper investigates bedrock heterogeneity by applying three different geophysical approaches, in order to study the long-term behaviour and the interaction between closed-loop geothermal systems. The ... [more ▼]

This paper investigates bedrock heterogeneity by applying three different geophysical approaches, in order to study the long-term behaviour and the interaction between closed-loop geothermal systems. The investigated site consists of four boreholes equipped with geothermal pipes on the campus of University of Liege, Belgium. The first approach includes acoustic borehole imaging, gamma-ray logging and cuttings observation and results to a detailed fracture characterisation, rock identification and layer dip angle determination. The second approach consists of measuring the thermal conductivity of cuttings at the laboratory. Study of cuttings thermal conductivity measurements can contribute to bedrock heterogeneity knowledge concerning the transition of one formation to another and the layer dipping. The third approach is based on high-resolution temperature profiles, measured during the hardening of the grouting material and the recovery phase of a Distributed Thermal Response Test. Through this approach a correlation of the temperature profiles to the geological characteristics of the surrounding bedrock is identified. The analysis of this correlation can provide information on fractured zones, alternation of different rock types and layering dipping. This latter approach can be easily applied on closed-loop geothermal systems to characterise the bedrock and investigate its heterogeneity as well as contribute to the their long-term behaviour prediction and to the optimisation of their efficiency. [less ▲]

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See detailHeterogeneous conversion of N2O5 to HNO3 in the post-Mount Pinatubo eruption stratosphere
Rinsland, Curtis P.; Gunson, Michaël R.; Abrams, M. C. et al

in Journal of Geophysical Research (1994), 99(D4), 8213-8219

Simultaneous stratospheric volume mixing ratio (VMR) profiles of dinitrogen pentoxide (N2O5) and nitric acid (HNO3) at sunrise between 25-degrees-N and 15-degrees-S latitude and profiles of HNO3 at sunset ... [more ▼]

Simultaneous stratospheric volume mixing ratio (VMR) profiles of dinitrogen pentoxide (N2O5) and nitric acid (HNO3) at sunrise between 25-degrees-N and 15-degrees-S latitude and profiles of HNO3 at sunset between 42-degrees-S and 53-degrees-S latitude have been derived from 0.01 cm-1 resolution infrared solar occultation spectra recorded 9 1/2 months after the massive eruption of the Mount Pinatubo volcano in the Philippine Islands. The measurements were obtained by the atmospheric trace molecule spectroscopy (ATMOS) Fourier transform spectrometer during the ATLAS 1 shuttle mission (March 24 to April 2, 1992). The measured HNO3 VMRs are higher at all altitudes and latitudes than corresponding values measured by the limb infrared monitor of the stratosphere (LIMS) instrument during the same season in 1979, when the aerosol loading was near background levels. The largest relative increase in the HNO3 VMR occurred near the equator at 30-km altitude, where the ATMOS/ATLAS 1 values are about a factor of 2 higher than the LIMS measurements. Two-dimensional model calculations show that the increase in HNO3 and the ATMOS/ATLAS 1 measurement of a steep decrease in the N2O5 VMR below 30 km can be explained by the enhanced conversion of N2O5 to HNO3 on the surfaces of the Mount Pinatubo sulfate aerosols. Our profile results demonstrate the global impact of the N2O5 + H2O --> 2HNO3 heterogeneous reaction in altering the partitioning of stratospheric odd nitrogen after a major volcanic eruption. [less ▲]

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See detailHeterogeneous incidence and propagation of spreading depolarizations
Kaufmann, D; SCHOENEN, Jean ULiege

in Journal of Cerebral Blood Flow & Metabolism (2018)

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See detailHeterogeneous incidence and propagation of spreading depolarizations.
Kaufmann, Dan; Theriot, Jeremy; Zyuzin, Jekaterina et al

in Journal of Cerebral Blood Flow & Metabolism (2017)

Spreading depolarizations are implicated in a diverse set of neurologic diseases. They are unusual forms of nervous system activity in that they propagate very slowly and approximately concentrically ... [more ▼]

Spreading depolarizations are implicated in a diverse set of neurologic diseases. They are unusual forms of nervous system activity in that they propagate very slowly and approximately concentrically, apparently not respecting the anatomic, synaptic, functional, or vascular architecture of the brain. However, there is evidence that spreading depolar- izations are not truly concentric, isotropic, or homogeneous, either in space or in time. Here we present evidence from KCl-induced spreading depolarizations, in mouse and rat, in vivo and in vitro, showing the great variability that these depolarizations can exhibit. This variability can help inform the mechanistic understanding of spreading depolarizations, and it has implications for their phenomenology in neurologic disease. [less ▲]

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