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Image Segmentation and Regular Partitions
Get PDFThis bachelor thesis contributes to the study of image segmentation and spectral graph theory. It aims at finding a link between image segmentation and equitable partitions, which are a common concept in spectral graph theory. The analysis consists of an algorithmic and a theoretical approach. During our research we could not find a strong connection between those two, however, we propose further areas to be investigated
Influence of Aerobic Exercise Induced Arousal on Neutral Word List Retrieval in Young Adults
Get PDFPrevious studies have shown that arousal during the encoding and consolidation phases facilitates memory performance, and that arousing stimuli are better remembered. The current study shifts attention to physical arousal in the retrieval phase. This study was designed to test whether physically induced arousal can enhance memory for neutral words. Participants (N = 48) were randomized over a control and an aerobic condition. On the first day they memorized a list of 30 words, on the second day they either watched a documentary or executed an aerobic cycling exercise before performing a memory recall and recognition test for the words memorized at day one. Prior to the main analyses a manipulation check on subjective and physiological arousal was conducted and a successful condition manipulation was confirmed. However, the analyses showed no significant difference in memory performance between groups. Implications and limitations are discussed
Changing the world, one word at a time: The struggles of higher education and communicative action in a capitalist world
Get PDFDebates within critical educational theory and its relation to capitalism have often been heavily influenced by the tradition of critical social theory. For instance, Jurgen Habermas’ communicative action approach has proven to be a valuable theory that combines both analytical considerations regarding the conflict between the ‘lifeworld’ and ‘system’, and a decisively normative theory for deliberative and democratic discourse. However, Habermas’ communicative action does not go without problems, as a critical linguistic approach may prove. As such, in this paper I attempt to analyse the issues of communicative action in the context of anti-capitalist discourse and debate within and about higher education. To do this, I first outline Habermas’ and Fleming’s theories on the colonization of higher education, followed by a critique by means of Wittgenstein’s philosophy of language. As such, I attempt to argue that, in order to decolonize higher education from the ‘logic of capital’, we must reflect upon the language-games used when speaking about education.
Trust-Building Risk Communication in the Post-Trust Era
Get PDFOn the Importance of Accountable RiskCommunication for the GM Food Producing Industr
Unlocking the Deadlocks? GMOs, Science and the Reform of the Legal Framework
Get PDFThe hydra is in many ways a well-working allegory for the numerous conflicts the EU has been facing in the GMO authorization process, and in particular regarding the complex deadlocks in the authorization of GMOs for cultivation. In the 1990s, heavy pressure at the international level2 caused the responsible EU decision-makers to establish a regulatory framework and the European Food Safety Authority (EFSA) to finally resolve their struggles with the de facto moratorium on GMO authorization. Unfortunately, this solution to the conflicts and struggles with GMO authorization did not prove to be sufficient. Even worse, the EU decision-makers faced what we call the first deadlock. It originated from the continuous bans of GMOs that Member States imposed with the safeguard clause, now in particular on GMO cultivation. As with the Hydra’s many heads which are growing back numerously every time one head is cut off, each time one issue was solved in the GMO authorization process, numerous other problems came up. When over time the new directive and agency proved not be the solution to the many conflicts and as there was no sign that GMO-opposing Member States would finally stop the banning, Member States from both camps – anti- and pro-GMO – instrumentalised the Commission to end the conflict on GMO authorization. The Commission attempted to do so by drafting a proposal,8 which arguably gave the Member States more freedom in deciding whether or not to cultivate GMOs in their territory. Thereby the Commission expected to accelerate the general authorization procedure for GMOs, as anti- GMO Member States could on the one hand agree on authorization of GMOs at the EU level, but also had the opportunity to ban their cultivation on national territory. Irrespective of the Commission’s attempt to solve the conflict and give the Member States more freedom, the proposal did not succeed in solving the deadlock. It was heatedly debated by EU officials and stakeholders, partly amended by the European Parliament (EP) and has not been adopted yet, as a blocking minority in the Council exists. We label this situation the ‘second deadlock’ – namely the deadlock on the solution of the first deadlock. After a couple of years of silence on this situation, the proposal and the whole deadlock situation suddenly became news again, when the Commission announced the revival of the talks and Monsanto, one the biggest GM producing companies, threatened to leave the European market in 2013. GMO authorization in the EU was never an easy topic, partly because the European public is not very fond of the idea of having GM-food on their table. Therefore, not only the heads of the hydra, but also the hydra itself can be compared to the GMO authorization process. In Greece mythology, the hydra was hated by the public as it murdered the farmers’ cattle at night. Unfortunately, up to now there was no Herakles in the EU, being able to find a solution on how to solve the deadlocks in GM- authorization. As there is no complete solution evident at the moment, we investigate to what extent the two deadlocks might be unlocked, also in light of the high prevalence of the topic in the news. Even though we are aware of the manifold aspects surrounding GM-authorization and cultivation, we aim to provide an overview for a broad scholarly public, not only on how the two deadlock arose and what were the exact issues at stake but also regarding the many heads of the hydra – namely the many issues decision-makers need to take into account – when trying to unlock the deadlocks. After explaining our research approach and methodology, our analysis first provides a general overview on the regulatory framework on GMOs. By describing the problems of authorization in practice, we investigate the first deadlock. Subsequently, some of the Hydra’s heads are cut off by means of analysing whether or not science is the solution to the first deadlock. The fourth section presents the Commission’s proposal to solve the deadlock, which is subsequently analysed on its legal viability regarding EU and WTO legislation. It is then attempted to solve the deadlock, or at least to provide some ideas on how to move a step towards solving it. Before concluding, we embed our proposal in the latest state-of-the-art academic literature
Chordoma and its embryonic determinants
Get PDFBackground. Chordomas are rare malignant tumors occurring along the axial skeleton that originate from notochordal remnants. It is hypothesized that embryonic factors are involved in their aetiology. In the present study, four such factors are of interest: EVX1, which mediates posterior patterning of the embryo and is found in prostate. Wnt3a, localized to the placenta, is involved in different proliferation signaling pathways. Twist is a mediator of the epithelial-mesenchymal transition (EMT) and is expressed in the neuroblastoma cell line SHSY 5Y. Finally, brachyury is a crucial EMT mediator and involved in cell cycle regulation. Research question. The research question is tripartite. (I) It is the aim to obtain positive control tissue for validation of embryonic primers for the EVX1, Wnt3a and Twist genes. (II) Second, expression of brachyury mRNA in cultured chordoma cells will be assessed in order to validate the cell line. (III) Last, it will be investigated whether fibroblast conditioned cell culturing medium exerts a positive effect on chordoma proliferation in vitro. Materials and methods. (I) Placenta and prostate samples were obtained from patients in the Maastricht University Hospital. mRNA was isolated from prostate, placenta and SHSY 5Y cells and cDNA of the genes of interest was generated after which PCR and gel electrophoresis was employed to yield amplicon bands. (II) Chordoma cells were cultured and brachyury mRNA expression was assessed by PCR assay. (III) Cultured chordoma cells were grown in enriched DMEM or in enriched DMEM containing 33% fibroblast conditioned medium and proliferation was assessed. Results. (I) Both EVX1 and Twist are positive in prostate and SHSY 5Y respectively. Wnt3a is not positive in placenta. (II) Brachyury expression is either strongly downregulated or not expressed in two slowly growing chordoma cell cultures. (III) First data indicate enriched DMEM containing 33% fibroblast conditioned medium does not stimulate chordoma proliferation in vitro as compared to enriched DMEM without fibroblast conditioned medium
The effect of bitter, umami and sweet tastants on the food intake regulation
Get PDFBackground. In the past decades, the prevalence of obesity and overweight has risen to epidemic dimensions. Nowadays, there is a great demand for new and efficient treatments to decrease this prevalence. Literature revealed, that the gastrointestinal tract contains taste receptors, similar to those present on the tongue, which may have an influence on the regulation of food intake and energy expenditure. However the exact working mechanism is unknown. Objective. This study investigated, the effects of the bitter-, sweet-, umami tastants and a combination of those on ad libitum food intake and gastrointestinal hormone release. Hypothesis. We hypothesized that an intraduodenal infusion of the bitter, umami and sweet tastants and a combination of these tastants, results in a significant reduction in food intake and an significant increase in the release of the gastrointestinal peptides GLP-1 and CCK. Furthermore, the largest reduction on ad libitum food intake, will be achieved by the combination treatment, because this will stimulate multiple taste receptors instead of just one group. Finally, a bitter infusion will induce greater effects on the ad libitum food intake and gastrointestinal hormone release, compared to the sweet and umami tastants. This because the bitter receptor is more sensitive to sense its tastant compared to the others.Methods. In this double blind, randomized, placebo controlled, cross-over study, we tested 15 healthy volunteers (Men: 5; Age 23.94±1.97 years; BMI 22.43±0.33 kg/m2 ). The study consisted of five identical test days. During these days, the effects of the tastants umami (Monosodium glutamate), sweet (Rebaudioside A), bitter (Quinine), a combination of these tastants and the placebo (tap water) treatment, were collected. This by infusing them into the duodenum by means of a nasoduodenal tube. Furthermore, multiple blood samples were drawn before, during and after the infusions to determine gastrointestinal peptide release of GLP-1 and CCK into the blood. Finally, an ad libitum pasta meal was provided to define the effects of the tastants on ad libitum meal intake
Fracking Expertise: How Interest Groups Used Expert Claims in Pennsylvania’s Fracking Controversy around Act 13
Get PDFHydraulic fracturing for shale gas extraction, also called fracking, is steadily growing as an energy source for the United States. Despite the technology’s promising economic opportunities, its application remains highly debated due to reported pollution incidents and uncertainties regarding long-term environmental and public health impacts. The regulation of fracking in the US is subject to federal state legislation. When the Commonwealth of Pennsylvania changed its fracking regulation in 2012, this sparked off a new round of debate. House bill 1950, often referred to as Act 13, expanded the possibilities for fracking in all areas of the state, even in housing districts and sensitive areas of high environmental value. Outraged, the affected municipalities decided to question the legality of the bill before court in March 2012. The case was closed in February 2014, when the Supreme Court judged the zoning prohibitions unconstitutional in a final say.
Conflicterende gezondheidsadviezen betreffende vitamine D: hoe maken ouders een afweging?
Get PDFIntroductie. Vitamine D wordt vooral verkregen via zonlicht en is een belangrijke nutriënt voor een goede ontwikkeling van kinderen. Voldoende blootstelling aan zonlicht is dus gewenst bij jonge kinderen, maar blootstelling aan de zon wordt ook geassocieerd met verbranding en huidkanker. Dit paper beschrijft het onderzoek naar de manier waarop ouders van kinderen tot vier jaar een keuze maken tussen de tegenstrijdige gezondheidsadviezen betreffende voldoende vitamine D inname voor kinderen uit de zon en de gezondheidsadviezen betreffende het vermijden van blootstelling aan te veel zon ter preventie van verbranding en huidkanker. Methode. In dit onderzoek is gebruik gemaakt van kwalitatief onderzoek met semigestructureerde interviews. Tien autochtone ouders met tenminste één kind in de leeftijd tot vier jaar werden bij hen thuis geïnterviewd. De vragenlijst bestond uit vragen over persoonskenmerken, algemene vragen over vitamine D, en open vragen die de onderzoeksvragen dekten. Alle transcripten werden aan de hand van de onderzoeksvragen en het theoretisch kader gecodeerd in het computerprogramma NVivo. Resultaten. De meeste participanten hadden nog nooit over het bestaan van conflicterende adviezen nagedacht. De meerderheid gaf aan, net zoals met de andere adviezen, te kiezen voor het advies waar zij het meest achterstond of het beste bij de situatie vond passen. Alle participanten vonden het belangrijker dat hun kind niet zou verbranden, met de consequentie dat deze dan onvoldoende vitamine D op zou doen. Dit werd onderbouwd met het feit dat de participanten hun kinderen supplementen gaven om toch voldoende vitamine D binnen te krijgen. Conclusie. Opvallend is dat de meeste ouders niet erkennen dat de gezondheidsadviezen die zij krijgen conflicterend kunnen zijn. In de gezondheidsvoorlichting zou hierop moeten worden ingespeeld, zodat ouders een beter afgewogen keuze kunnen maken
Bioavailability and antioxidant effect of ergothioneine in human blood
Get PDFEdible mushrooms, such as the white button mushrooms contain several biological compounds including ergothioneine (ET). The main function of ET seems to be to protect cells from oxidative stress. Although humans cannot synthesize ET, the human body does have its own ergothioneine transporter (ETT), which allows cells, for instance red blood cells (RBCs), to take up and store ET. The existence of this transporter suggests that ET might have a physiological importance in humans. The aims of this study were to examine the availability of ET in RBCs and the protective effect of ET on oxidative stress in RBCs. The uptake of ET in RBCs was studied in vitro by treating RBCs with known concentrations of ET (0-100 µM). The amount of ET in the RBCs was determined using high performance liquid chromatography (HPLC). The protective effect of ET was studied by measuring the haemolysis in oxidative stress induced RBCs, which were pre-treated with ET in concentrations ranging from 0-100 µM. In addition, a pilot study was performed where 10,6 mg ET was administered to subjects (n = 6) through a mushroom soup. Before and three hours after consumption, blood samples were collected. The blood samples were analyzed to determine the concentration ET in the RBCs using HPLC and the protective effect of ET was studied the same way as for in vitro. Main findings were that ET was taken up in RBCs after treatment with all ET concentrations, but only after 30 minutes and two hours. Furthermore, RBCs pre-treated with ET had less haemolysis than nontreated RBCs; pre-treatment with 100 µM ET was observed to significantly (p<0,016) decrease haemolysis in comparison with the non-treated RBCs. Consumption of the mushroom soup did not result in increased ET levels in the RBCs, although three out of five subjects had less haemolysis compared to consumption of the placebo soup. However, the beneficial effects after consumption of the mushroom soup cannot be assigned to ET for sure; other unobserved compounds could be involve