Vraaggestuurd lezen:Een metacognitieve aanpak van begrijpend lezen

In opdracht van Kennisne

Rapture or risk: Signs of the end or symptoms of world risk society?

This is an Accepted Manuscript of an article published by Taylor & Francis Group in Culture and Religion on 11 December 2014 available online: http://www.tandfonline.com/10.1080/14755610.2014.982670In this article I argue that elements of contemporary fundamentalist Christian apocalyptic discourse are not only influenced by, but are a product of the rhetoric and fascination with the notion of risk. The world risk society thesis developed by the German sociologist Ulrich Beck will be utilised as a conceptual framework to measure one example of an online discourse centred on a Christian dispensationalist understanding of the rapture: Rapture Index. This popular website utilises a statistical probability index system based on 45 different categories that relate to global socio-political events; the higher the aggregate total the nearer the rapture. The Rapture Index is indebted to the impact of risk in contemporary society and it is a tool that exemplifies non-knowing: a product of the world risk society

Agrammatic but numerate

A central question in cognitive neuroscience concerns the extent to which language enables other higher cognitive functions. In the case of mathematics, the resources of the language faculty, both lexical and syntactic, have been claimed to be important for exact calculation, and some functional brain imaging studies have shown that calculation is associated with activation of a network of left-hemisphere language regions, such as the angular gyrus and the banks of the intraparietal sulcus. We investigate the integrity of mathematical calculations in three men with large left-hemisphere perisylvian lesions. Despite severe grammatical impairment and some difficulty in processing phonological and orthographic number words, all basic computational procedures were intact across patients. All three patients solved mathematical problems involving recursiveness and structure-dependent operations (for example, in generating solutions to bracket equations). To our knowledge, these results demonstrate for the first time the remarkable independence of mathematical calculations from language grammar in the mature cognitive system

Vascular risk factors, atherosclerosis, cerebral white matter lesions and cerebral perfusion in a population-based study

We studied risk factors for cerebral vascular disease (blood pressure and hypertension, factor VIIc, factor VIIIc, fibrinogen), indicators of atherosclerosis (intima-media thickness and plaques in the carotid artery) and cerebral white matter lesions in relation to regional cerebral blood flow (rCBF) in 60 persons (aged 65-85 years) recruited from a population-based study. rCBF was assessed with single-photon emission tomography using technetium-99m d,l-hexamethylpropylene amine oxime (99mTc-HMPAO). Statistical analysis was performed with multiple linear regression with adjustment for age, sex and ventricle-to-brain ratio. A significant positive association was found between systolic and diastolic blood pressure and temporo-parietal rCBF. In analysis with quartiles of the distribution, we found a threshold effect for the relation of low diastolic blood pressure (≤ 60 mmHg) and low temporo-parietal rCBF. Levels of plasma fibrinogen were inversely related to parietal rCBF, with a threshold effect of high fibrinogen levels (> 3.2 g/l) and low rCBF. Increased atherosclerosis was related to low rCBF in all cortical regions, but these associations were not significant. No consistent relation was observed between severity of cerebral white matter lesions and rCBF. Our results may have implications for blood pressure control in the elderly population

Plasma chemistry and kinetics in a magnetized hydrogen plasma expansion : a study of negative ions

Studying hydrogen plasmas is of great importance from a fundamental point of interest since hydrogen is the most abundant molecule in the known universe and from a theoretical point of view the simplest to work on. In industry, hydrogen containing plasmas are used for example in surface modification, thin film deposition and creating negative hydrogen ions in neutral beam injectors for future fusion devices. In this work the hydrogen plasma is created by a cascaded arc plasma source which expands in a low pressure surrounding. When an external magnetic field is applied to this expansion a confined plasma column is created with two distinct color regions. At a specific distance from the source of expansion a sharp transition from a red light emitting plasma (dominated by H_ emission) to a blue light emitting plasma (dominated by H_, H and H_ emission) occurs. The main research question was to understand the kinetics in the plasma expansion. Since atomic processes alone cannot explain the distinct emissions observed in the two different regions, molecular processes such as dissociative recombination and processes involving negative hydrogen ions were suspected to be key in the understanding of the underlying mechanisms. Therefore, the relevance of this work was to underpin the importance of these molecular processes in atomic regimes of hydrogen containing plasmas both by simulation and experiment. A Collisional Radiative model (CR-model), which includes molecular processes, was used to simulate the spatially resolved excited state densities. This CR-model assumes quasi steady state and requires as input the temperature of the species (the heavy particle temperature Tgas and the electron temperature Te) and the density of the species (the electron density, the atomic hydrogen density, the molecular hydrogen density, the positive ion densities of H+, H+2 and H+3 and the negative ion density). The output of the CR-model gives excited state densities of atomic hydrogen which are compared with the measured excited state densities as determined using two diagnostics: tunable diode laser absorption spectroscopy for the first excited state n=2 and absolute optical emission spectroscopy for n=3-9. Only when the two molecular mutual neutralization processes of H+2 and H+3 with H- are included in the CR-model, good agreement for all the investigated excited state densities of n=2 up to n=9 was obtained. Since we suspected that the excited states of atomic hydrogen are mainly populated by processes involving negative hydrogen ions a novel photo-detachment technique was developed. This technique uses a laser to photo-detach all present negative hydrogen ions in the detection volume in combination with an optical detection setup to monitor time dependently the change of Balmer line emission. We have shown that the atomic mutual neutralization process of H+ with H-mainly populates the excited state n=3 in the red light emitting plasma and that a branching ratio of the molecular mutual neutralization process of H+2 with H- mainly populates the excited state n=3 up to 9 in the blue light emitting plasma. We have also shown that there are processes involving negative ions that do not lead to the population of excited states, namely the molecular mutual neutralization process of H+3 and H- and a branching ratio of the molecular mutual neutralization process of H+2 and H-.The main conclusion of all the presented work is that we now have a much better understanding of the kinetics of weakly magnetized expanding hydrogen plasmas. The two distinct color regions that are resulting from specific Balmer line emission can be explained by populating molecular processes in the plasma, i.e. dissociative recombination and processes involving negative hydrogen ions

FUNCTIONAL SCREENING OF CYTOCHROME P450 ACTIVITY AND UNCOUPLING BY CAPILLARY ELECTROPHORESIS

Cytochrome P450s are a super-family of heme containing proteins that are found in all domains of life and are involved in the synthesis and breakdown of steroids, xenobiotics, and pharmaceuticals. Using five heterologously expressed zebrafish (Danio rerio) CYP1s, an assay was developed for CYP activity in order to monitor the consumption of the cofactor NADPH, providing a label-free screening tool to determine function of novel CYP genes. Using well-established fluorogenic substrates, NADPH and NADP+ were separated by capillary electrophoresis (CE) from stopped CYP1 reactions and measured with UV absorbance detection as a surrogate to assess the rate of substrate metabolism. Product formation was confirmed by fluorometric detection of metabolites, giving rates of enzyme activity which could be compared to the rates of cofactor turn-over measured by CE. 17β-estradiol, four alkoxyresorufin and two coumarin based synthetic fluorogenic CYP substrates were screened for activity with recombinant zebrafish CYP1A, 1B1, 1C2, 1C2 and 1D1. Cofactor consumption was generally much larger than product formation for the majority of substrates and CYP1 isoforms, suggesting that the majority of metabolic events were uncoupled. Large uncoupling was seen in CYP1 when metabolizing estradiol, showing that endogenous compounds can also show severe uncoupling. Reactive oxygen species (ROS), a product of uncoupled events, were detected with 2,7- dichorofluorescein. Attempts for concomitant detection of ROS production and cofactor consumption with CE-UV detection were investigated, however, detection limits for 2,7-dichlorofluorescein were not adequate for detection of hydrogen peroxide production from CYP1 mediated reactions. Future work will be required to develop a single assay to quantitatively measure CYP activity by CE for functional determination of CYPs with unknown function.Master of Science (MSc

Linguistic deficits in the acute phase of stroke

Background and Purpose: For the diagnosis of aphasia early after stroke, several screening tests are available to support clinical judgment. None of these tests enables the clinician to assess the underlying linguistic deficits, i. e. semantic, phonological and syntactic deficits, which provides indispensable information for early therapeutic decisions. The ScreeLing was designed as a screening test to detect semantic, phonological and syntactic deficits. The ScreeLing's sensitivity, specificity and accuracy in detecting aphasia and semantic, phonological and syntactic deficits were determined. Methods: The ScreeLing was validated in an acute stroke population against a combined reference diagnosis of aphasia (aphasia according to at least two of the following measures: neurologist's judgment, linguist's judgment, Tokentestscore). The three ScreeLing subtests were validated in the aphasic population against the presence or absence of a semantic, phonological and/or syntactic deficit according to an experienced clinical linguist. Results: From a consecutive series of 215 stroke patients, 63 patients were included. The ScreeLing was an accurate test for the detection of aphasia (0.92), with a sensitivity of 86% and specificity of 96%. Sensitivity of subtests was 62% for semantics, 54% for phonology and 42% for syntax. Specificity was 100% for semantics and phonology and 80% for syntax, and accuracy 0.84 for semantics, 0.87 for phonology and 0.64 for syntax. Conclusions: The ScreeLing is an accurate test that can be easily administered and scored to detect aphasia in the first weeks after stroke. Furthermore, the ScreeLing is suitable for revealing underlying linguistic deficits, especially semantic and phonological deficits

The CAMCOG: a useful screening instrument for dementia in stroke patients

BACKGROUND and PURPOSE: Most mental screening tests focus on the detection of cognitive deficits compatible with Alzheimer's disease. Stroke patients who develop a dementia syndrome, however, constitute a more heterogeneous group with both cortical and subcortical disturbances. We assessed the diagnostic accuracy of the CAMCOG (the cognitive and self-contained part of the Cambridge Examination for Mental Disorders of the Elderly) and the Mini-Mental State Examination (MMSE) for dementia in patients with a recent stroke. METHODS: In patients age