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The anticue task: no effect of working memory load on inhibitory control
Get PDFSeveral studies have reported a close link between inhibitory control and working memory (WM), however the exact mechanisms remain elusive. The present study was designed to investigate the effect of WM load on inhibitory control using a novel paradigm – the anticue keypress task. 22 right-handed students (21.0 ± 1.2 years; 11 males) performed four counterbalanced dual-task conditions on a computer: (pro- / anticue) x (high / low WM load). Three randomized preparation intervals, i.e. 150, 250 and 450 ms, separated cue and target onsets in all reaction time trials. No interaction was observed for the factor WM load with the pro- or anticue task, F(1, 21) = .21, p = .65. In conclusion, no distinctive influence of WM load on inhibitory control (anticue) compared to automatic response selection (procue) was found. Therefore, it is suggested that independent neural areas underlie WM performance and inhibitory control
The Effect of Casein Ingestion within a Milk Matrix on Muscle Protein Synthesis
Get PDFIsolated micellar casein has been classified as a slow protein because of its slow digestion and amino acid absorption kinetics. These result further in a more moderate and sustained amino acid availability in the plasma and subsequently lower muscle protein synthesis (MPS) rate when, for example, compared with whey. However, the milk matrix with lactose, fat and various minerals may modulate the effect of casein on MPS. Therefore, this study aimed to compare the effects of the ingestion of casein dissolved in bovine milk serum to the ingestion of isolated casein on myofibrillar protein synthesis. In this parallel group randomized trial, 32 healthy older men (age: 71 ± 1 y) received a primed continuous infusion of L-[ring-2 H5 ]phenylalanine, L-[1-13C]leucine, and L-[ring-3,5-2 H2 ]tyrosine and blood and muscle samples were taken to assess myofibrillar fractional synthetic rate (FSR) under basal postabsorptive conditions and after a single bolus of 25 g intrinsically L-[1-13C]phenylalanine and L-[1-13C]leucine-labeled casein either in an isolated form (ISOCAS; n = 16) or dissolved in bovine milk serum (MILK-CAS; n = 16). The ingestion of 25 g of casein significantly (P < 0.05) increased MPS rates in both groups when assessed over the late postprandial period (t = 120 – 300 min). Ingestion of MILK-CAS and ISO-CAS did not significantly stimulate MPS rates when assessed over the early (t = 0 – 120 min) and overall (t = 0 – 300 min) postprandial FSR compared to postabsorptive (t = -120 – 0 min) FSR. No significant differences were observed between the two groups over the early, late or entire postprandial period (P > 0.05). The ingestion of additional normal milk matrix to micellar casein does not modulate overall myofibrillar protein synthesis rates in older men when compared to the ingestion of micellar casein dissolved in water. Therefore, there is neither a benefit, nor a detrimental effect of ingesting micellar casein within a normal milk matrix instead of the isolated form to increase MPS
Relationship between sensory processing sensitivity and hypochondriacal features and the moderating role of somatic symptoms
Get PDFBackground. Only very little is known about the etiology of hypochondriasis, a mental disorder characterized by the preoccupied beliefs or fears of having a serious disease or being in a life-threatening condition and the elevated focus on own physical symptoms. A relatively new concept named sensory processing sensitivity (SPS) is about the sensitivity towards stimuli and is related to an elevated self-focus. Due to its relation with an elevated self-focus, SPS might be related to hypochondriacal features. The present study investigated this relationship. Moreover, in the light of recent reformulation of hypochondriasis in the DSM-5 in illness anxiety disorder and somatic symptom disorder, this study also examined how the presence of somatic complaints affects the relationship between SPS and hypochondriacal features. Methods. A cross-sectional questionnaire study was conducted in which 302 participants from the general population were enrolled. These participants were recruited through several ways online and at several physical locations. Hypochondriacal fears and beliefs were assessed using the Illness Attitudes Scale (IAS), while SPS was assessed using the Highly Sensitive Person scale (HSP). At last, having physical complaints was assessed with descriptive items on having complaints and their duration and location. Results. The present study found that HSP and its subscales Ease of Excitation and Low Sensory Threshold were positively and significantly correlated to IAS and its subscales Health Anxiety and Illness Behavior. In contrast, it was found that the Aesthetic Sensitivity subscale of the HSP scale was not correlated to IAS or its subscales. Furthermore, a moderation test using linear regression analyses showed that having somatic complaints did not moderate the relationship between HSP and IAS. Having specifically chronic somatic complaints, however, did tend to moderate this relationship. Conclusion. The present study is the first study to show the importance of a high SPS in having hypochondriacal fears and beliefs and the role of somatic complaints in this relationship. However, future research is needed to further understand this relationship and to investigate its causalit
Transnational border surveillance and social sorting systems in the EU: a changing approach to Europe\u27s borders?
Get PDFIn recent years, the European Union (EU) has widened its competences considerably in the field of transnational surveillance. The main databases for border movements, Schengen Information System (SIS), Visa Information System (VIS), and Eurodac, are planned to merge increasingly to ensure maximum efficiency in surveillance. These databases are keeping track of movement within the EU and across its borders, mainly for the purpose of controlling migration . This process of harmonising migration surveillance systems is controversial. All three databases entail large-scale surveillance of migrants and travellers thereby turning every recorded individual into a potential suspect. As the European Data Protection Supervisor stated, "all travellers are put under surveillance and are considered a priori as potential law breakers".David Lyon (2003), the founder of surveillance studies, assesses that transnational surveillance systems classify individuals according to certain criteria that allow for discriminatory treatment. Thereby, social differences are created and stored, which he labels social sorting. Social sorting, in other words, refers to surveillance systems obtaining data for the purpose of classifying people according to specific criteria. Classification occurs according to risk categories such as citizens, migrants or potential criminals. This may lead to establishing or strengthening social differences. Starting out from Lyon\u27s assumption that every form of surveillance entails social sorting, this paper assesses in how far and with what consequences such classification is found in present-day EU surveillance systems. If they display social sorting characteristics to a high degree, this indicates that the traditional function of borders of exclusion and inclusion of migrants is to some extent taken over by the new surveillance systems. The question then arises how this form of social sorting affects the concept of the border in the EU. The intended merger of transnational databases will create an increasingly sophisticated information infrastructure that may alter the function of territorial boundaries. If border surveillance is no longer confined to checking documents "on the ground" but is carried out "in the cloud", what does this entail for the concept of the territorial border
‘Is er invloed van de fysieke omgeving op het succes van een advies-op-maat interventie gericht op lichamelijke activiteit?’
Get PDFAchtergrond. Lichamelijke activiteit is een beschermende factor voor verschillende ziekten, zoals hart-en vaatziekten, kanker en diabetes. In Nederland beweegt een groot deel van de volwassenen te weinig, slechts 40% voldoet aan de Nederlandse norm voor gezond bewegen. Deze norm houdt in dat men minimaal 5 dagen per week, minstens 30 minuten matig intensief moet bewegen (bijvoorbeeld wandelen of fietsen). Het bevorderen van lichamelijke activiteit is een belangrijk onderwerp in de public health en er zijn al vele interventies ontwikkeld die zich richten op het stimuleren van lichamelijke activiteit. Tot nu toe zijn de effecten van dit soort interventies klein gebleken, daarom is het belangrijk dat wordt onderzocht onder welke omstandigheden interventies meer effectief kunnen zijn. De duidelijke associatie tussen de fysieke omgeving en lichamelijke activiteit is een reden waarom omgeving wellicht een beïnvloedende factor kan zijn voor een interventieeffect. Met de fysieke omgeving wordt bedoeld hoe de omgeving eruit ziet waarin een individu leeft, bijvoorbeeld de aanwezigheid van fiets/voetpaden of sportfaciliteiten. Het succes van een interventie zou ook gerelateerd kunnen zijn met opleiding, vanwege het feit dat laagopgeleiden vaker inactief zijn. Doel. Onderzoeken of het effect van een advies-op-maat interventie wordt beïnvloed door de fysieke omgeving en opleidingsniveau. Het effect van de interventie wordt gemeten door het voldoen aan de beweegnorm en de intentie tot meer bewegen. Methode. De studie werd uitgevoerd als een gerandomiseerde gecontroleerde trial (RCT) met een controle en een interventiegroep. De uitkomstmaten (voldoen aan de beweegnorm en intentie), kenmerken van de fysieke omgeving en sociaal demografische kenmerken zijn gemeten op de voormeting en na 1 maand follow-up, door middel van een vragenlijst. In totaal hebben 2159 respondenten, met een leeftijd van minimaal 30 jaar, deelgenomen aan het onderzoek. De data zijn geanalyseerd met behulp van meervoudige logistische en lineaire regressie. De uitkomstmaat werd hierbij gebruikt als de afhankelijke variabele en studiegroep en de interactie tussen omgeving/opleiding en groep werden gebruikt als onafhankelijke variabelen. Alle analyses werden uitgevoerd voor zowel de totale studiepopulatie als de risicogroep. De risicogroep werd gedefinieerd als niet voldoen aan de beweegnorm op de voormeting. Resultaten. Er was geen interactie met opleidingsniveau in zowel de totale studiepopulatie als in de risicogroep voor intentie om meer te gaan bewegen of voldoen aan de beweegnorm, wat impliceert dat er geen verschil was in interventie effect naar opleiding. Er is geen interactie (voor beide uitkomstmaten) gevonden met fysieke omgeving in zowel de totale studiepopulatie als in de risicogroep. De interventie heeft geresulteerd in een hoger percentage respondenten uit de risicogroep dat voldeed aan de beweegnorm (OR=1,34, 95%=1,00-1,80). Conclusie. In deze studie kon niet worden aangetoond dat de effecten van de interventie werden beïnvloed door fysieke omgevingsfactoren. De advies-op-maat interventie was effectief in het verhogen van lichamelijke activiteit bij mensen die op de voormeting niet aan de beweegnorm voldeden
Toxicity of hair dyes in human keratinocytes Effects of Basic Yellow 57 in combination with Resorcinol and Hydrogen Peroxide
Get PDFBackground. In the United States and Europe, more than 30% of women over 18 years and approximately 10% of men over 40 years are using hair colouring products. Previous studies have shown that low concentrations of the semi-permanent hair dye Basic Yellow 57 (BY57) lead to toxicity in human keratinocytes. The aim of this study is to investigate the DNA damaging effects of BY57 in combination with other (oxidizing) components, such as hydrogen peroxide (a bleach component) and resorcinol (a colour coupler) in human keratinocyte (HaCaT) cells. Furthermore, another aim of the present study is to evaluate the potential DNA damaging mechanisms caused by these hair dye components. Methods. The HaCaT cells were exposed to different concentrations BY57 (0-100 µg/ml), hydrogen peroxide (0-100 µM), resorcinol (0-100 µg/ml) and to the possible combinations of these components. Diphenyleneiodonium (DPI; 10 and 50 µg/ml) and hydroxyurea (HU; 10 mM) were added to the keratinocytes to evaluate the potential DNA damaging mechanisms. DPI was applied as an NADPH oxidase inhibitor and HU functions as an DNA polymerase inhibitor. In the present study, the tested concentrations are based on the proportion of the hair dye components as present in commercially available hair dye products. In order to detect potential DNA fragmentation after treating the cells with the different hair dye components, the single cell gel electrophoresis (comet) assay was used. Results. Treatment of the HaCaT cells with hydrogen peroxide (100 µM) and Basic Yellow 57 (100 µg/ml) lead to a significant induction of DNA fragmentation in human keratinocytes. The combination of BY57 together with hydrogen peroxide and resorcinol lead to a significant induction in DNA damage. However, this induction was approximately equal to the DNA damaging effects caused by hydrogen peroxide only. Furthermore, the addition of DPI lead to an unexpected induction of DNA fragmentation. Conclusion. The present results showed that the exposure of human keratinocytes to Basic Yellow 57, hydrogen peroxide and the combination treatments of the hair dye components containing hydrogen peroxide lead to an induction of DNA fragmentation. However, the possible working mechanisms of DNA damaging effects caused by BY57 remains unclear. The DNA damaging effects of DPI could suggest an inhibition of the DNA repair system via the inhibition of NADPH oxidase. Since this effect is not confirmed by the results of the DNA repair inhibitor (HU), no conclusion could be drawn from these findings. To elucidate the possible DNA damaging mechanisms of BY57 on human keratinocytes, further research is needed
Report on the Global Tax Policy Conference Amsterdam, 6 March 2014
Get PDFThe first Global Tax Policy Conference of the Maastricht Centre for Taxation was held at The Royal Netherlands Academy of Arts and Sciences in Amsterdam, the Netherlands on 6 March 2014. The purpose of the day was to share the knowledge and views on global tax policy through interactive discussions about key issues and emerging challenges in the dynamic area of tax policy.
Patient’s Outcome Expectancies and Treatment Outcome Influence of Patient’s Outcome Expectancies on Symptom Improvement and Drop-out in Interpersonal Psychotherapy and Cognitive Therapy for adult depression
Get PDFThis study aims to explore the influence of expectations on treatment outcome of depressed patients following Interpersonal Psychotherapy or Cognitive Therapy. Patients’ baseline outcome expectations might influence post-treatment symptom improvement and dropout during treatment. Outcome expectations are hypothesized to influence the level of symptom improvement and the drop-out risk. The current study is based on data collected in a large RCT in which participants are assigned to either Cognitive Psychotherapy (N=76) or Interpersonal Psychotherapy (N=75) in order to be treated for a primary depressive episode. The Outcome Expectations Questionnaire was conducted at baseline, followed by a 7 months intervention phase. The primary outcome measurement is symptom improvement, which is the difference in symptoms at 7 months and at baseline. The second outcome measurement, drop-out, is the percentage participants that stop the treatment after following less than 12 session, while still having complains. The relationship between outcome expectations and symptom improvement and between outcome expectations and drop-out were analyzed separately. Contradictory to the hypothesis, the data did not show a significant relationship between outcome expectations and symptom improvement or drop-out. These findings implicate that patients with low outcome expectations have the same symptom improvement and risk to drop-out of the treatment as patients with high expectations. Other studies support this findings. However, more well-designed major studies are needed in order to gather more evidence-based information on the influence of outcome expectations on treatment outcome
The predictive vs. the simulating brain: A literature review on the mechanisms behind mimicry
Get PDFIs it possible to understand the intentions of other people by observing their actions? And how does unconscious mimicking and synchronizing to behavior from other people relate to that? Behavioral synchrony and mimicry are important elements of social cognition. Their settings and effects have been well studied. However, the neurobiological mechanism behind them remains unclear. This review illuminates two neuroscientific approaches to explain the mechanism behind behavioral synchrony and mimicry. On the one hand, simulation through the mirror neuron system (MNS) describes behavioral synchrony as a by-product of simulation by certain motor-neurons. On the other hand, forward and inverse models, an internal prediction about future events, seem to be an important concept in motor control and have been suggested to be involved in social cognition as well. The author proposes that behavioral synchrony relates to forward and inverse models by acting as a facilitator of social cognition. A better prediction, due to behavioral synchrony, leads to a better understanding of others. Furthermore, limitations of the given approaches are illuminated
Jet lag: symptoms, causation and minimization
Get PDFIn this literature review we provide an overview of what jet lag is, how it is caused, what contributes to a less or more severe experience of jet lag and what we can do about it. Jet lag is a misalignment of the human circadian rhythm which is regulated by our Suprachiasmatic Nucleus in the brain and caused by crossing time zones too fast for our biological clock to keep up. Main symptoms are intense sleepiness or insomnia at inappropriate times. Other symptoms can be cognitive impairments like loss of motivation and concentration, loss of appetite, altered digestive functions, diarrhea, depressive symptoms and decreased physical performance can also occur. This is defined as jet lag. There is no aid to totally avoid jet lag, but there are ways to minimize the symptoms. Jet lag can be minimized by phase advancing or delaying the circadian rhythm before a flight with help of exposure or avoidance of bright light, melatonin and pre-adjusting the sleep schedule. The same resources can be used after arrival to reduce the symptoms