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This special issue addresses the imagination of futures ‘away from home’ in a globalising world. While a growing number of migration scholars have taken into account that migration considerations are always socially embedded and culturally informed, the processes at work among a mounting number of (young) men and women throughout the world, who are convinced that a better life can only be found ‘away from home’, have been notably understudied. This special issue goes beyond the study of migration aspirations as a question of migration only. It focuses on the specific contexts (in five different countries) within which migration dreams are born, and sometimes even cultivated. It explores the sociocultural embedding of these aspirations by investigating the interpretation of local realities versus global possibilities, and examines how the aspirations of so many worldwide link up to the wider interconnections between globalisation and the sociocultural, political and economic transformations ‘back home’.

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Het Wii-spel ‘De ontdekker en de diamanten scarabee’ ontwikkeld door MAD Multimedia, Principal Blue, Koninklijke Visio en TNO, heeft weer een prijs gewonnen. Tijdens de Dutch Game Awards 2012, dé vakprijzen voor de Nederlandse gamesindustrie, werd het spel uitgeroepen tot de beste Serious Game. In 2011 heeft TNO op verschillende conferenties al de co-creatie kennisaspecten van het project gedeeld. Slechtziende, blinde en goed ziende kinderen hebben de inhoud en de vorm van het spel mede bepaald. Fysiotherapeuten, bewegingswetenschappers en -docenten keken mee naar de motorische aspecten. Doel van de ontwikkeling van het spel was om het leven van blinde kinderen een sociale en fysieke stimulans te geven. Die missie is zeer geslaagd. De Ontdekker won eerder al vier prijzen: de Oogfonds Innovatieprijs 2011, een award in de Creative City Challenge 2011, de e-virtuoses “Best project” Award 2012 en de Serious Game Expo “Innovation Award” 2012.

Recent years have seen a large amount of empirical studies related to ‘embodied cognition’. While interesting and valuable, there is something dissatisfying with the current state of affairs in this research domain. Hypotheses tend to be underspecified, testing in general terms for embodied versus disembodied processing. The lack of specificity of current hypotheses can easily lead to an erosion of the embodiment concept, and result in a situation in which essentially any effect is taken as positive evidence. Such erosion is not helpful to the field and does not do justice to the importance of embodiment. Here we want to take stock, and formulate directions for how it can be studied in a more fruitful fashion. As an example we will describe few example studies that have investigated the role of sensori-motor systems in the coding of meaning (‘embodied semantics’). Instead of focusing on the dichotomy between embodied and disembodied theories, we suggest that the field move forward and ask how and when sensori-motor systems and behavior are involved in cognition.

Aims The EUTrigTreat clinical study has been designed as a prospective multicentre observational study and aims to (i) risk stratify patients with an implantable cardioverter defibrillator (ICD) for mortality and shock risk using multiple novel and established risk markers, (ii) explore a link between repolarization biomarkers and genetics of ion (Ca 2, Na, K) metabolism, (iii) compare the results of invasive and non-invasive electrophysiological (EP) testing, (iv) assess changes of non-invasive risk stratification tests over time, and (v) associate arrythmogenomic risk through 19 candidate genes. Methods and resultsPatients with clinical ICD indication are eligible for the trial. Upon inclusion, patients will undergo non-invasive risk stratification, including beat-to-beat variability of repolarization (BVR), T-wave alternans, T-wave morphology variables, ambient arrhythmias from Holter, heart rate variability, and heart rate turbulence. Non-invasive or invasive programmed electrical stimulation will assess inducibility of ventricular arrhythmias, with the latter including recordings of monophasic action potentials and assessment of restitution properties. Established candidate genes are screened for variants. The primary endpoint is all-cause mortality, while one of the secondary endpoints is ICD shock risk. A mean follow-up of 3.3 years is anticipated. Non-invasive testing will be repeated annually during follow-up. It has been calculated that 700 patients are required to identify risk predictors of the primary endpoint, with a possible increase to 1000 patients based on interim risk analysis. ConclusionThe EUTrigTreat clinical study aims to overcome current shortcomings in sudden cardiac death risk stratification and to answer several related research questions. The initial patient recruitment is expected to be completed in July 2012, and follow-up is expected to end in September 2014. © The Author 2011.

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Disarmament, demobilization and reintegration (DDR) is a set of activities that forms part of strategies for peacebuilding after civil war. DDR has become the standard way of addressing security threats in immediate post-conflict situations. However, DDR is designed to promote national security, rather than human- or community security. This creates severe obstacles for success, if success is seen in terms of overall security promotion rather than defined merely in numbers of arms collected and people demobilized. The reason is that if security at community level is not improved, then people will be unable to abandon armed violence as a way of protection and of making a living. Disarmament in such a situation will probably be only temporary. Thus, it is a necessity for DDR to aim at community security. However, when community security becomes the aim, then this opens up questions about whether DDR is the most appropriate strategy. At best, it can be part of a more wide-ranging strategy, which in addition to top-down DDR programs also involves community-based activities. Altogether, such a holistic security promotion strategy should endeavor to make people and communities better able to protect themselves and to create a living that does not depend on war and violence. In other words, it should aim at making guns redundant. ‘Community-based’ and ‘Second-generation’ DDR initiatives lend inspiration for such a wider security promotion approach. What they show is that the optimal approach is very context-specific. Analysis of the conflict, of local security mechanisms, and of the needs and capacities of communities, therefore has to be the first step, despite the fact that this takes valuable time.

According to theories of embodied cognition, understanding a verb like throw involves unconsciously simulating the action throwing, using areas of the brain that support motor planning. If understanding action words involves mentally simulating our own actions, then the neurocognitive representation of word meanings should differ for people with different kinds of bodies, who perform actions in systematically different ways. In a test of the body-specificity hypothesis (Casasanto, 2009), we used fMRI to compare premotor activity correlated with action verb understanding in right- and left-handers. Right-handers preferentially activated left premotor cortex during lexical decision on manual action verbs (compared with non-manual action verbs), whereas left-handers preferentially activated right premotor areas. This finding helps refine theories of embodied semantics, suggesting that implicit mental simulation during language processing is body-specific: Right and left-handers, who perform actions differently, use correspondingly different areas of the brain for representing action verb meanings.

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Nowadays, six types of acquired vancomycin resistance in enterococci are known; however, only VanA and to a lesser extent VanB are widely prevalent. Various genes encode acquired vancomycin resistance and these are typically associated with mobile genetic elements which allow resistance to spread clonally and laterally. The major reservoir of acquired vancomycin resistance is Enterococcus faecium; vancomycin-resistant Enterococcus faecalis are still rare. Population analysis of E. faecium has revealed a distinct subpopulation of hospital-acquired strain types, which can be differentiated by molecular typing methods (MLVA, MLST) from human commensal and animal strains. Hospital-acquired E. faecium have additional genomic content (accessory genome) including several factors known or supposed to be virulence-associated. Acquired ampicillin resistance is a major phenotypic marker of hospital-acquired E. faecium in Europe and experience has shown that it often precedes increasing rates of VRE with a delay of several years. Several factors are known to promote VRE colonisation and transmission; however, despite having populations with similar predispositions and preconditions, rates of VRE vary all over Europe.

This thesis represents an excursion into the world of molecular electronics, i.e. the field of research trying to use individual (organic) molecules as electronic components; in this work various experimental methods have been explored to connect individual molecules to metallic contacts and determine their electronic properties. The drive for this research is twofold. On the one hand there is the rush towards ever smaller electronics. Using individual molecules in integrated circuits would further shrink the size of electronic components. On the other hand, different theories have to be used (and developed) to describe the conductance of electrons through matter as the dimensions of the material in question become smaller and smaller. This is because the (conduction) properties of a material change with changing size. In other words, research into the field of molecular electronics yields new fundamental insights into the interaction of electrons with matter at the nanoscale. In this thesis two elementary models, namely a Self Consistent Field model and a Coulomb model, have been used to investigate the conduction properties of (a single energy level of) a single molecule between two metal contacts. Various parameters of these two models were systematically varied to see what their influence is on the conductance. In particular, the effect of the coupling (of the molecule to the metallic leads) on the conduction was studied carefully for both models. For the Self Consistent Field model it was shown, that, for symmetric coupling constants, the conductance reaches a maximum, namely the quantum of conductance, as the magnitude of the couplings becomes large. For highly non-symmetric coupling constants though the conductance drops to zero. In case of the Coulomb model it was observed that using coupling constants whose magnitudes have a ratio that is far from unity, resulted in a polarity dependent Coulomb blockade behavior: for one bias polarity Coulomb blockade occurred, while for the other polarity it did not. These model calculations were performed to back up the two kinds experiments that were designed and performed to measure the electrical properties of a single molecule between two metallic contacts. The first method consisted of pushing colloidal gold nanoparticles in between two lithographically defined metallic contacts (to reduce the size of the gap between these two electrodes to a few nanometers) with the tip of an atomic force microscopy (AFM) and subsequently apply molecules to the (in size reduced) gap. It was found that a fully connecting chain of colloids, so without any molecules yet added to the device, did not conduct at all. The reason for the lack of conduction turned out to be the presence of an electrically insulating shell (of citrate molecules) around each colloid. Using microwave radiation, it was attempted to remove this shell. While microwave irradiation removed the shell and even caused individual colloids to melt and coalesce, the process could not be controlled to the extent that metallic contacts with a separation of 1 to 2 nm could reliably be produced. In the second method the reverse was attempted: Instead of reducing the size of the gap, it was attempted to controllably create a gap of nanometer dimensions from a fully connected metallic structure, to which molecules could subsequently be applied. The process by which these gaps were created is called electromigration and basically consists of applying a high enough current(density) to a metallic wire to break it. It was found that to reliably create gaps with dimensions of 1 to 2 nm, it was necessary to add a series resistor to the system to obtain the correct overall resistance value. Too low a resistance value, i.e. no series resistor added, resulted in gaps that had size-distributions that were too large for the gaps to be of use. Too high a resistance value, namely too large a series resistor, resulted in gaps that were also useless, because for these gaps the exact gap size could not be determined, since the tunneling current flowing through these gap was too low to be determined. With the correct overall resistance, 30 for these particular kind of structures, gaps with dimensions of a few nanometers could be reliably made more than 85% of the time. Placing an individual molecule in such a gap turned out to be more troublesome, as none of the 76 created structures resulted in a electrical measurement on a single molecule. As an alternative to creating nanometer sized contacts, local probe oxidation has been performed on self-assembled monolayers (that consist of octadecyl trichlorosilane molecules on a silicon(oxide) substrate). With local probe oxidation, which is an AFM technique, an electric current is passed through a conductive tip (by applying a bias between tip and substrate), to selectively modify the surface area. In this fashion a pattern is written on the substrate as the tip is scanned across the surface. From literature it is known that such patterns could, for example, be used to selectively coat parts of the substrate with metals and in this fashion create nano-scale electronic contacts. Before this can be done effectively, however, it is necessary to control the oxidation process. Two processes can occur when a bias is applied, namely the modification of the methyl end-groups of the molecules that form the monolayer into carboxylic acid groups, which is desirable, and growth of silicon oxide underneath the monolayer, which is undesirable. It was found that, depending on the oxidation conditions, i.e. the applied bias and the duration over which it is applied, a distinction can be made between these two processes. It is also observed that, depending on the scan direction of the AFM, the end-group modification can be observed as either an increase or a decrease of the height of the modified areas due to cross-coupling, i.e. mixing, of the simultaneously recorded height and friction signals of the AFM. To truly measure the conduction properties of individual molecules, scanning tunneling microscopy was used to measure the conductivity of thiophenol molecules absorbed on a silver(111) substrate. It was found that the molecules form ordered monolayers on the substrate with a 3 p 3 × 3 unit cell. The performed conduction experiments revealed vibrational features that could be related to the presence of vibrational modes of the thiophenol molecule as well as to phonon modes of the silver substrate. By comparing these conduction experiments with computational simulations, it was determined that, depending on the exact position of the tip above the molecule, electrons can take different pathways through the molecule and thereby excite different atomic/molecular vibrations. The calculations also showed that the composition of the tip has an important effect on the obtained IET spectrum as well. Additionally, it has been observed that the conductance spectrum is asymmetric around 0 Volts, which is attributed to a realignment of the molecule due to its dipole interaction with the applied electric field, and has a characteristic dip for voltages below 40 mV that is thought to be caused by the interplay between the silver phonon modes and the thiophenol molecules.

Sinds 1990 worden in Nederland op grote schaal beheersovereenkomsten met boeren afgesloten. Ook binnen de Europese Unie zijn deze 'agri-environment schemes' een belangrijk speerpunt van het landbouwbeleid geworden. De grote vraag is of de weidevogels van dit beleid profiteren

Enterococci (Enterococcus faecalis and Enterococcus faecium) are relatively avirulent enteric bacteria that usually only cause infections in immunocompromised patients. Antimicrobial treatment, however, is hampered as enterococci are intrinsically resistant to many antibiotics. For years, vancomycin was considered the last available antibiotic. Plasmid-mediated resistance against vancomycin among enterococci was first described in the nineteen-eighties and since then incidences of infection caused by vancomycin-resistant enterococci (VRE) have increased dramatically, especially in the United States. In 2000, three outbreaks of VRE occurred in hospitals in the Netherlands and a set of infection-control measures was proposed to limit further transmission. These measures were based on the simultaneous isolation of VRE from multiple patients. All three outbreaks were controlled by these measures and no new outbreaks in Dutch hospitals have been reported since then. Epidemiological studies have shown that hospital outbreaks on three continents were caused by a subpopulation of E. faecium, which is characterized by the presence of a potential virulence gene (variant esp) and resistance to amoxicillin. This 'hospital strain' of E. faecium has probably been prevalent within hospital settings for some time, but only became clinically relevant when it had acquired vancomycin-resistance. Current advice is to implement the set of infection control measures formulated in 2000, only in those patients colonized by amoxicillin-resistant VRE. The potential dangers of VRE were recently underlined by the proven transmission of the vancomycin-resistance gene from VRE to methicillin-resistant Staphylococcus aureus (MRSA) in two patients in the United States. It is in the interest of the patients that prevalence of VRE and MRSA in Dutch hospitals should be kept as low as possible

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