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The momentary, global functional state of the brain is reflected by its electric field configuration. Cluster analytical approaches consistently extracted four head-surface brain electric field configurations that optimally explain the variance of their changes across time in spontaneous EEG recordings. These four configurations are referred to as EEG microstate classes A, B, C, and D and have been associated with verbal/phonological, visual, attention reorientation, and subjective interoceptive-autonomic processing, respectively. The present study tested these associations via an intra-individual and inter-individual analysis approach. The intra-individual approach tested the effect of task-induced increased modality-specific processing on EEG microstate parameters. The inter-individual approach tested the effect of personal modality-specific parameters on EEG microstate parameters. We obtained multichannel EEG from 61 healthy, right-handed, male students during four eyes-closed conditions: object-visualization, spatial-visualization, verbalization (6 runs each), and resting (7 runs). After each run, we assessed participants' degrees of object-visual, spatial-visual, and verbal thinking using subjective reports. Before and after the recording, we assessed modality-specific cognitive abilities and styles using nine cognitive tests and two questionnaires. The EEG of all participants, conditions, and runs was clustered into four classes of EEG microstates (A, B, C, and D). RMANOVAs, ANOVAs and post-hoc paired t-tests compared microstate parameters between conditions. TANOVAs compared microstate class topographies between conditions. Differences were localized using eLORETA. Pearson correlations assessed interrelationships between personal modality-specific parameters and EEG microstate parameters during no-task resting. As hypothesized, verbal as opposed to visual conditions consistently affected the duration, occurrence, and coverage of microstate classes A and B. Contrary to associations suggested by previous reports, parameters were increased for class A during visualization, and class B during verbalization. In line with previous reports, microstate D parameters were increased during no-task resting compared to the three internal, goal-directed tasks. Topographic differences between conditions concerned particular sub-regions of components of the metabolic default mode network. Modality-specific personal parameters did not consistently correlate with microstate parameters except verbal cognitive style which correlated negatively with microstate class A duration and positively with class C occurrence. This is the first study that aimed to induce EEG microstate class parameter changes based on their hypothesized functional significance. Beyond, the associations of microstate classes A and B with visual and verbal processing, respectively and microstate class D with interoceptive-autonomic processing, our results suggest that a finely-tuned interplay between all four EEG microstate classes is necessary for the continuous formation of visual and verbal thoughts, as well as interoceptive-autonomic processing. Our results point to the possibility that the EEG microstate classes may represent the head-surface measured activity of intra-cortical sources primarily exhibiting inhibitory functions. However, additional studies are needed to verify and elaborate on this hypothesis.
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BACKGROUND Estimates of the size of the undiagnosed HIV-infected population are important to understand the HIV epidemic and to plan interventions, including "test-and-treat" strategies. METHODS We developed a multi-state back-calculation model to estimate HIV incidence, time between infection and diagnosis, and the undiagnosed population by CD4 count strata, using surveillance data on new HIV and AIDS diagnoses. The HIV incidence curve was modelled using cubic splines. The model was tested on simulated data and applied to surveillance data on men who have sex with men in The Netherlands. RESULTS The number of HIV infections could be estimated accurately using simulated data, with most values within the 95% confidence intervals of model predictions. When applying the model to Dutch surveillance data, 15,400 (95% confidence interval [CI] = 15,000, 16,000) men who have sex with men were estimated to have been infected between 1980 and 2011. HIV incidence showed a bimodal distribution, with peaks around 1985 and 2005 and a decline in recent years. Mean time to diagnosis was 6.1 (95% CI = 5.8, 6.4) years between 1984 and 1995 and decreased to 2.6 (2.3, 3.0) years in 2011. By the end of 2011, 11,500 (11,000, 12,000) men who have sex with men in The Netherlands were estimated to be living with HIV, of whom 1,750 (1,450, 2,200) were still undiagnosed. Of the undiagnosed men who have sex with men, 29% (22, 37) were infected for less than 1 year, and 16% (13, 20) for more than 5 years. CONCLUSIONS This multi-state back-calculation model will be useful to estimate HIV incidence, time to diagnosis, and the undiagnosed HIV epidemic based on routine surveillance data.
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We engineer a brane picture for the reduction of Seiberg dualities from 4D to 3D, valid also in the presence of orientifold planes. We obtain effective 3D dualities on the circle by T-duality, geometrizing the non-perturbative superpotential which is an affine Toda potential. When reducing to pure 3D, we define a double-scaling limit which creates a sector of interacting singlets, giving a unified mechanism for the brane reduction of dualities.
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Sport-motor tests play an important role in football talent selections. However, single tests represent only parts of the complex game performance. The best game performance therefore does not necessarily need to go hand in hand with the best results in all tests of a test battery. Considering the complexity of the game performance appropriately, a holistic perspective together with a person-oriented approach are applied. Thereby, systems consisting of several variables are identified and analysed in a longitudinal study. Following this idea, six sport-motor tests were aggregated into a subsystem. 106 young male elite football players were tested three times (2011, 2012, 2013; Mage, t2011=12.26, SD=0.29). One year later (2014) their performance level was enquired. Data were analysed using the LICUR method, a cluster analytical method. Four patterns were identified, which remained stable at all measuring points. The players frequently show intraindividual and structurally similar patterns over time. At the third measuring point, a pattern occurred out of which the players are significantly more likely to advance to the highest performance level one year later. This pattern appears consistently above average, but does not always show best test performances. The significantly frequent development along structurally stable patterns suggests a predictive validity of the subsystem sport-motor tests between the ages of 12 to 15. Above average, but not necessarily outstanding performances both in the motor abilities as well as in the football specific tests appears to be particularly promising. This finding emphasizes the need of a holistic perspective in the talent selection.
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PURPOSE To assess whether Bcl-2, an inhibitor of the apoptotic cascade, can predict response to neoadjuvant chemotherapy in patients with urothelial cancer of the bladder (UCB). METHODS Bcl-2 expression was analyzed in 2 different tissue microarrays (TMAs). One TMA was constructed of primary tumors and their corresponding lymph node (LN) metastases from 152 patients with chemotherapy-naive UCB treated by cystectomy and pelvic lymphadenectomy (chemotherapy-naive TMA cohort). The other TMA was constructed of tumor samples obtained from 55 patients with UCB before neoadjuvant chemotherapy (transurethral resection of the bladder cancer) and after cystectomy with pelvic lymphadenectomy (residual primary tumor [ypT+], n = 38); residual LN metastases [ypN+], n = 24) (prechemotherapy/postchemotherapy TMA cohort). Bcl-2 overexpression was defined as 10% or more cancer cells showing cytoplasmic immunoreactivity. RESULTS In both TMA cohorts, Bcl-2 overexpression was significantly (P<0.05) more frequent in LN metastases than in primary tumors (chemotherapy-naive TMA group: 18/148 [12%] in primary tumors vs. 39/143 [27%] in metastases; postchemotherapy TMA: ypT+7/35 [20%] vs. ypN+11/19 [58%]). In the neoadjuvant setting, patients with Bcl-2 overexpression in transurethral resection of the bladder cancer specimens showed significantly (P = 0.04) higher ypT stages and less regression in their cystectomy specimens than did the control group, and only one-eighth (13%) had complete tumor regression (ypT0 ypN0). In survival analyses, only histopathological parameters added significant prognostic information. CONCLUSIONS Bcl-2 overexpression in chemotherapy-naive primary bladder cancer is related to poor chemotherapy response and might help to select likely nonresponders.
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Autologous stem cell transplantation (ASCT) is applied to consolidate first remission in patients with acute myeloid leukaemia (AML). However, outcome after ASCT widely varies among AML patients. We analyzed the prognostic significance of haematological recovery for neutrophils [absolute neutrophil count (ANC) >1·0 × 10(9) /l] and platelets (platelet count >20·0 × 10(9) /l), stratifying at day 20 after ASCT in 88 consecutive and homogeneously treated AML patients in first remission. We observed that patients with delayed recovery had better overall survival (OS; ANC: P
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For Michael Polanyi, religion and science fight abreast to protect the occidental culture from totalitarian threat. Both are belief-based endeavors, Polanyi is convinced. While this is not surprising at all regarding religion, it is surely a provocation regarding science. The article tries to explore this original thought of Polanyi and to examine how it is rooted in his personal convictions and beliefs. Special emphasis is given to Polanyi’s critique of contemporary biology, as expressed in his article on “Science and Religion”, in some ways a response to Paul Tillich’s theology. Contemporary biology’s findings undermine exactly what Polanyi is fighting for, hence he is convinced that its findings are somewhat flawed. This should however not lead to the false conclusion that Polanyi had anything to do with creationism or would have favored Intelligent Design in our days.
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The distribution of trivalent and tetravalent cerium, Ce(III) and Ce(IV) respectively, in a lateritic profile from Madagascar, has been characterized by X-ray-absorption near-edge structure (XANES) spectroscopy at the Ce LIII-edge on the LUCIA beamline (SOLEIL synchrotron, France). XANES spectra were acquired on bulk-rock samples as well as on specific lateritic minerals or polymineral zones (in-situ measurements) of the tonalite bedrock and the three overlying weathered horizons (C-, B- and A-horizons). Geochemically, the bedrock, and the A- and C-horizons show similar rare earth element content (REE = 363–405 mg/kg). They also display the same positive Ce-anomaly (CeCN/Ce∗ = 1.12–1.45), which is therefore likely to be inherited from the bedrock. In the B-horizon, the higher REE content (REE = 2194 mg/kg) and the larger Ce-anomaly (CeCN/Ce∗ = 4.26) are consistent with an accumulation zone caused by the evaporation of groundwater during the dry season. There is a good agreement between the Ce(III)/Cetotal ratio (XCe(III)) deduced from the positive Ce-anomaly (bulk-rock geochemical data) and that derived from XANES spectroscopy on the same bulk-rock samples (BR-XCe(III)-XANES) in the bedrock, and the C- and B-horizons. In the A-horizon, XANES measurements on bulk rock and minerals revealed a higher BR-XCe(III)-XANES (up to 100%) compared to the XCe(III) deduced from geochemical data (XCe(III) = 79%). The preservation of a positive Ce-anomaly in the A-horizon suggests that the Ce mobilization and redistribution during weathering occurred with no significant Ce fractionation from other trivalent REE. Remarkably, the only investigated sample where cerianite is observed belongs to the B-horizon. Within this horizon, Ce oxidation state varies depending on the microstructural position (porosity, cracks, clay-rich groundmass). The highest Ce(IV) concentrations are measured in cerianite (and aluminophosphates) localized in pores at the vicinity of Mn-rich domains (XCe(III)-XANES = 30–51%). Therefore, Ce fractionation from other REE is attributed to a Ce oxidation and precipitation potentially assisted by oxyhydroxide scavenging. In the C-horizon, Ce(III) and Ce(IV) are mainly distributed in REE-minerals of the rhabdophane group found in pores and cracks. The similarity between the Ce(III) proportion of rhabdophane grains (XCe(III)-XANES = 74–89%) with that of the bedrock (BR-XCe(III)-XANES = 79%) suggests no significant fractionation of Ce(III) and Ce(IV) between solution and mineral during the successive stages of primary REE-mineral alteration, transport in solution and secondary precipitation in the incipient stages of weathering. Overall, our novel spectroscopic approach shows that Ce is not necessarily oxidized nor fractionated from other REE during weathering in lateritic conditions. This implies that like Ce(III), Ce(IV) can be mobilized in aqueous fluids during weathering, possibly thanks to complexation with organic molecules, and can precipitate together with Ce(III) in secondary REE-bearing minerals. The corollary is that (paleo)redox reconstructions in soils and/or sediments based on Ce-anomaly in weathered rocks or minerals must be interpreted with caution.
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