123 research outputs found
IMPACT OF WATER RADIOLYSIS ON URANIUM DIOXIDE CORROSION
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Combined investigation of water sorption on rutile (1 1 0) single crystal face: XPS vs. periodic DFT
XPS and periodic DFT calculations have been used to investigate water sorption on the TiO2 rutile (1 1 0) face. Two sets of XPS spectra were collected on the TiO2 (1 1 0) single crystal clean and previously exposed to water: the first set with photoelectrons collected in a direction parallel to the normal to the surface; and the second set with the sample tilted by 70°, respectively. This tilting procedure promotes the signals from surface species and reveals that the first hydration layer is strongly coordinated to the surface and also that, despite the fact that the spectra were recorded under ultra-high vacuum, water molecules subsist in upper hydration layers. In addition, periodic DFT calculations were performed to investigate the water adsorption process to determine if molecular and/or dissociative adsorption takes place. The first step of the theoretical part was the optimisation of a dry surface model and then the investigation of water adsorption. The calculated molecular water adsorption energies are consistent with previously published experimental data and it appears that even though it is slightly less stable, the dissociative water sorption can also take place. This assumption was considered, in a second step, on a larger surface model where molecular and dissociated water molecules were adsorbed together with different ratio. It was found that, due to hydrogen bonding stabilisation, molecular and dissociated water molecules can coexist on the surface if the ratio of dissociated water molecules is less than ≈33%. These results are consistent with previous experimental works giving a 10–25% range
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Cerebellar induced differential polyglot aphasia: a neurolinguistic and fMRI study
Research has shown that linguistic functions in the bilingual brain are subserved by similar neural circuits as in monolinguals, but with extra-activity associated with cognitive and attentional control. Although a role for the right cerebellum in multilingual language processing has recently been acknowledged, a potential role of the left cerebellum remains largely unexplored.
This paper reports the clinical and fMRI findings in a strongly right-handed (late) multilingual patient who developed differential polyglot aphasia, ataxic dysarthria and a selective decrease in executive function due to an ischemic stroke in the left cerebellum. fMRI revealed that lexical-semantic retrieval in the unaffected L1 was predominantly associated with activations in the left cortical areas (left prefrontal area and left postcentral gyrus), while naming in two affected non-native languages recruited a significantly larger bilateral functional network, including the cerebellum. It is hypothesized that the left cerebellar insult resulted in decreased right prefrontal hemisphere functioning due to a loss of cerebellar impulses through the cerebello-cerebral pathways
Archeologische opgraving Herent Kouterstraat
Dit rapport werd ingediend bij het agentschap samen met een aantal afzonderlijke digitale bijlagen. Een aantal van deze bijlagen zijn niet inbegrepen in dit pdf document en zijn niet online beschikbaar. Sommige bijlagen (grondplannen, fotos, spoorbeschrijvingen, enz.) kunnen van belang zijn voor een betere lezing en interpretatie van dit rapport. Indien u deze bijlagen wenst te raadplegen kan u daarvoor contact opnemen met: [email protected]
Lattice dynamical study of optical modes in Tl2Mn2O7 and In2Mn2O7 pyrochlores
The Raman, IR and force field have been investigated for A2Mn2O7 (A= Tl, In)
by means of a short-range force constant model which includes four stretching
and four bending force constants. Unusual spectral and force field changes are
observed and analyzed. The stretching force constant Mn-O and A-O, are found to
be relatively higher than those of other pyrochlore oxides of the A2Mn2O7
family, while the remaining force constant values are significantly smaller,
especially for Tl2Mn2O7. This trend may be due to strong hybridization of the
Tl (6s) orbital with O (2p) and Mn (3d). The assignment of all the modes has
been proposed and potential energy distribution is also reported. The evaluated
frequencies are close to the available observed infrared and Raman frequencies,
giving further support to the present assignments.Comment: To be published in PRB, 17 page
GalNAc/Gal-Binding Rhizoctonia solani Agglutinin Has Antiproliferative Activity in Drosophila melanogaster S2 Cells via MAPK and JAK/STAT Signaling
Rhizoctonia solani agglutinin, further referred to as RSA, is a lectin isolated from the plant pathogenic fungus Rhizoctonia solani. Previously, we reported a high entomotoxic activity of RSA towards the cotton leafworm Spodoptera littoralis. To better understand the mechanism of action of RSA, Drosophila melanogaster Schneider S2 cells were treated with different concentrations of the lectin and FITC-labeled RSA binding was examined using confocal fluorescence microscopy. RSA has antiproliferative activity with a median effect concentration (EC50) of 0.35 µM. In addition, the lectin was typically bound to the cell surface but not internalized. In contrast, the N-acetylglucosamine-binding lectin WGA and the galactose-binding lectin PNA, which were both also inhibitory for S2 cell proliferation, were internalized whereas the mannose-binding lectin GNA did not show any activity on these cells, although it was internalized. Extracted DNA and nuclei from S2 cells treated with RSA were not different from untreated cells, confirming inhibition of proliferation without apoptosis. Pre-incubation of RSA with N-acetylgalactosamine clearly inhibited the antiproliferative activity by RSA in S2 cells, demonstrating the importance of carbohydrate binding. Similarly, the use of MEK and JAK inhibitors reduced the activity of RSA. Finally, RSA affinity chromatography of membrane proteins from S2 cells allowed the identification of several cell surface receptors involved in both signaling transduction pathways
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Constraint-induced Aphasia Therapy versus Intensive Semantic Treatment in Fluent Aphasia
Objective: To compare the effectiveness of two intensive therapy methods: Constraint- 4 Induced Aphasia Therapy (CIAT) and semantic therapy (BOX).
Method: Nine patients with chronic fluent aphasia participated in a therapy programme 6 to establish behavioral treatment outcomes. Participants were randomly assigned to one of two groups (CIAT or BOX).
Results: Intensive therapy significantly improved verbal communication. However, BOX 9 treatment showed a more pronounced improvement on two communication measures, namely on a standardized assessment for verbal communication, the Amsterdam Nijmegen Everyday Language Test (Blomert, Koster, & Kean, 1995) and on a subjective rating scale, the Communicative Effectiveness Index (Lomas et al., 1989). All 13 participants significantly improved on one (or more) subtests of the Aachen Aphasia Test (Graetz et al., 1992), an impairment-focused assessment. There was a treatment-specific effect. Therapy with BOX had a significant effect on language comprehension and on semantics, while of CIAT affected language production and phonology.
Conclusion: The findings indicate that in patients with fluent aphasia (1) intensive treatment has a significant effect on language and verbal communication, (2) intensive therapy results in selective treatment effects and (3) an intensive semantic treatment shows a more striking mean improvement on verbal communication in comparison to communication-based CIAT-treatment
Diversity in Protein Glycosylation among Insect Species
status: publishe
MEMOR: A database of archeological human remains collections from Flanders, Belgium
The aim of this article is to describe a newly created open access database of archeological human remains collections from Flanders, Belgium. The MEMOR database (www.memor.be) was created to provide an overview of the current practices of loans, reburial, and the research potential of human skeletons from archeological sites currently stored in Flanders. In addition, the project aimed to provide a legal and ethical framework for the handling of human remains and was created around stakeholder involvement from anthropologists, geneticists, contract archeologists, the local, regional and national government agencies, local and national government, universities, and representatives of the major religions. The project has resulted in the creation of a rich database with many collections available for study. The database was created using the open-source Arches data management platform that is freely available for organizations worldwide to configure in accordance with their individual needs and without restrictions on its use. Each collection is linked to information about the excavation and the site the remains originate from, its size and time period. In addition, a research potential tab reveals whether any analyses were performed, and whether excavation notes are available with the assemblage. The database currently contains 742 collections, ranging in size from 1 to over 1000 individuals. New collections will continue to be added when new assemblages are excavated and studied. The database can also be expanded to include human remains collections from other regions and other material categories, such as archaeozoological collections
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