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A crucial challenge in future smart energy grids is the large-scale coordination of distributed energy generation and demand. In the last years several Demand Side Management approaches have been developed. A major drawback of these approaches is that they mainly focus on realtime control and not on planning, and hence cannot fully exploit the flexibility of e.g. electric vehicles over longer periods of time. In this chapter we investigate the optimization of charging an electric vehicle (EV). More precisely, the problem of charging an EV overnight is formulated as a Stochastic Dynamic Programming (SDP) problem. We derive an analytic solution for this SDP problem which in turn leads to a simple short-term bidding strategy. From an MDP point of view this solution has a number of special features: • It leads to analytic optimal results based on order statistics. • It allows for a more practical rule which can be shown to be nearly optimal. • It is robust with respect to the modeling assumptions, showing little room for further improvement even when compared to a solution with perfect foresight. Numerical results with real-world data from the Belgium network show a substantial performance improvement compared to standard demand side management strategies, without significant additional complexity. (This chapter is based on Kempker et al. (Proceedings of the 9th EAI international conference on performance evaluation methodologies and tools, Valuetools 2015, Berlin, 14–16 December 2015, pp 1–8, 2016).)

We report on a study on a representative set of Fe$_{2}$P-based MnFePSi samples by means of $^{55}$Mn NMR in both zero and applied magnetic field. The first-order nature of the magnetic transition is demonstrated by truncated order parameter curves with a large value of the local ordered moment at the Curie point, even at compositions where the transition appears second order from magnetic measurements. No weak ferromagnetic order could be detected at Si-poor compositions showing the kinetic arrest phenomenon, but rather the phase separation of fully ferromagnetic domains from volume fractions where Mn spins are fluctuating. The more pronounced decrease of the ordered moment at the $3f$ sites on approaching $T_C$, characteristic of the mixed magnetism of these materials, is demonstrated to be driven by a vanishing spin density rather than enhanced spin fluctuations at the $3f$ site. An upper limit of 0.03~$\mu_B$ is set for the fluctuating Mn moment at the $3f$ site by the direct detection of a $^{55}$Mn NMR resonance peak in the Mn-rich samples above $T_C$, showing nearly temperature-independent frequency shifts. A sharper secondary peak observed at the same compositions reveals however the disproportionation of a significant $3f$-Mn fraction with negligible hyperfine couplings, which retains its diamagnetic character across the transition, down to the lowest available temperatures. Such a diamagnetic fraction qualitatively accounts for the reduced average $3f$ moment previously reported at large Mn concentrations., Comment: 12 pages, 13 figures. Submitted to Phys. Rev. B

Onderwijswetenschappers willen graag weten welke leerstrategieën het meest effectief zijn om leerstof te onthouden, daarom is daar reeds veel onderzoek naar gedaan. Een leerstrategie die zijn effectiviteit in veel gevallen heeft bewezen is distributed practice. Bij distributed practice wordt alle leerstof geoefend in meerdere sessies met pauzes ertussen. Bij massed practice daarentegen wordt alle leerstof in één langere sessie geoefend.Binnen dit onderzoek werd gekeken naar de toepassing van distributed practice bij het oefenen voor een toets aardrijkskunde in groep 7 van de basisschool. Het doel was om te inventariseren welke leerstrategieën de leerlingen kennen en toepassen bij het oefenen van hun huiswerk. Daarnaast werd gekeken in hoeverre de leerlingen distributed practice toepassen. Ten slotte werd onderzocht of het spacing effect optreedt wanneer de leerlingen oefenen voor een toets aardrijkskunde met distributed practice.Aan dit onderzoek namen 37 leerlingen van de twee groepen 7 van de 2e Marnixschool in Utrecht deel. De leerlingen kregen een vragenlijst over leerstrategieën. Daarnaast werd een onderzoek uitgevoerd, waarbij de leerlingen voor twee toetsen aardrijkskunde oefenden middels retrieval practice. De condities verschilden voor beide toetsen: bij de ene toets ging het oefenen via massed practice, bij de andere toets via distributed practice. Het was een within-subjects design waarbij de toetsresultaten per deelnemer werden vergeleken. Om verschil in resultaten door de moeilijkheidsgraad van de toets te ondervangen werd counterbalancing toegepast. Voor het inventariseren van de leerstrategieën die de leerlingen kennen en toepassen werd gebruik gemaakt van een vragenlijst die bestond uit open vragen, gesloten vragen en een survey waarbij de leerlingen antwoorden gaven op een 5-punts Likertschaal. Bij het onderzoek werd bestaand materiaal van de methode Wijzer door de wereld 7 (Kessels et al., 2008) gebruikt. De meest gebruikte leerstrategie was herlezen, daarnaast maakten leerlingen vaak gebruik van retrieval practice, vooral door zich te laten overhoren. Hoewel de leerlingen zelf niet vaak spreiden van de leerstof noemden, bleek uit de survey dat zij dit wel regelmatig toepasten. Uit de toetsresultaten bleek dat het spacing effect niet optrad na distributed practice bij het oefenen voor een toets aardrijkskunde. Mogelijke verklaringen zijn dat de tussenpozen (gap) tussen de oefenmomenten niet optimaal waren in verhouding tot de tijd tussen het laatste oefenmoment en de toets (retention interval). Bij een retention interval van twee dagen is de ideale gap 9,6 tot 19,2 uur, terwijl in het onderzoek de gap 24 uur bedroeg. Daarnaast kan de complexiteit van de leerstof van invloed zijn. Een uitgebreidere inventarisatie van gebruikte leerstrategieën door leerlingen in de bovenbouw van de basisschool zou interessant zijn. Ook nader onderzoek naar distributed practice bij het oefenen van zaakvakken als aardrijkskunde kan aanknopingspunten geven voor het al dan niet optreden van het spacing effect.

Peatlands represent a vast carbon reserve that has accumulated under conditions of low nitrogen availability. Given the strong coupling between the carbon and nitrogen cycles, we need to establish the consequences of the increase in reactive nitrogen deposition for the sustainability of peatlands, and whether the form in which the nitrogen is deposited makes a difference. We have addressed these questions using a globally unique field simulation of reactive N deposition as dry deposited ammonia and wet deposited reduced N, ammonium and oxidised N, nitrate, added as ammonium chloride or sodium nitrate, to an ombrotrophic peatland, Whim bog in SE Scotland. Here we report the fate of 56 kg N ha−1 yr−1 additions over 10 yr and the consequences. The effects of 10 yr of reactive N additions depended on the form in which the N was applied. Ammonia-N deposition caused the keystone Sphagnum species, together with the main shrub Calluna and the pleurocarpous mosses, to disappear, exposing up to 30% of the peat surface. This led to a significant increase in soil water nitrate and nitrous oxide emissions. By contrast wet deposited N, despite significantly reducing the cover of Sphagnum and Pleurozium moss, did not have a detrimental effect on Calluna cover nor did it significantly change soil water N concentrations or nitrous oxide emissions. Importantly 10 yr of wet deposited N did not bare the peat surface nor significantly disrupt the vegetation enabling the N to be retained within the carbon rich peatland ecosystems. However, given the significant role of Sphagnum in maintaining conditions that retard decomposition, this study suggests that all nitrogen forms will eventually compromise carbon sequestration by peatlands through loss of some keystone Sphagnum species.

An approach is presented to compare two Markov Chains, particularly Continuous-Time Markov Chains (CTMC) such as to model Queueing Networks (QN). Here one may typically think of one CTMC or QN to be a solvable modification (e.g. a product form QN) of the other one, say the original, which is of practical interest but unsolvable. The approach is essentially based upon evaluating performance measures by cumulative reward structures and analytically bounding so-called bias-terms, also known as relative gains or fundamental matrix elements. A general comparison and error bound result will be provided. The approach, referred to as Markov Reward approach, is related to Stochastic Dynamic programming and • may lead to analytic error bounds for the discrepancy, and • may still apply while stochastic comparison fails To motivate and illustrate the approach, the presentation will contain an instructive finite tandem queue example and a practical result for a real-life application of an Operation Theater-Intensive care unit system. Some remaining questions for research will be addressed briefly.

Een bloedtransfusie is een veilige, veel voorkomende en soms levensreddende medische behandeling, waarbij rode bloedcellen afkomstig van een donor worden ingebracht in de bloedbaan van een transfusieontvanger die deze nodig heeft vanwege bijvoorbeeld een chirurgische ingreep (orgaantransplantatie, hartchirurgie) of een hematologische aandoening (leukemie, sikkelcelanemie, thalassemie). Hierbij is het van belang dat de bloedgroepen van de donor en transfusieontvanger zoveel mogelijk overeenkomen, of anders gezegd, dat hun bloedgroepen matchen.

Some medical problems, such as syncope, have direct consequences for fitness to drive. Our objective was to discover if patients had been informed about their driving status after a syncopal episode by their physician, and if this advice was in line with current legislation. Cross-sectional study. By means of a structured questionnaire, 150 patients referred to the syncope clinic at the Academic Medical Centre, Amsterdam, were asked about the advice they had received concerning their driving status during previous consultations with their general practitioner or specialists. A syncope expert then assessed the driving status of all patients in the light of the existing and new ruling. In 121 of the 150 patients (81%), a certain or highly-likely cause for their loss of consciousness was determined: 68 patients had reflex syncope, 25 patients orthostatic hypotension, 20 patients psychogenic pseudosyncope, three patients cardiac syncope, three patients had epilepsy and two patients another diagnosis. Seven patients had experienced an episode while driving. Only 26/150 patients (17%) reported that the consequences of their episodes for their driving status had been discussed with them at earlier consultations. If driving was discussed, in only 31% had the current Dutch legislation on driving been followed. Over a third (38%) of the patients felt they should no longer drive. Fewer than one in five patients reported that driving status was discussed by a physician after a syncope episode. If advice had been given, it was often not in line with current legislation

Background It is becoming increasingly apparent that the plantaris can contribute to symptoms in at least a subset of patients with mid-portion Achilles tendinopathy. However the nature of its involvement remains unclear. Hypothesis / Purpose To determine whether excised plantaris tendons from patients with mid-portion Achilles tendinopathy display tendinopathic changes and whether the presence of such changes affect clinical outcomes. Methods Sixteen plantaris tendons patients with mid-portion Achilles tendinopathy recalcitrant to conservative management underwent histological examination for the presence of tendinopathic changes. All patients had imaging to confirm the presence of the plantaris tendon adherent to or invaginated into the focal area of Achilles tendinosis. Visual analogue scores (VAS) and foot and ankle outcome scores (FAOS) were recorded pre and post-operatively. Results Sixteen patients (mean age 26.2; 18-47 years) underwent surgery with a mean follow-up of 14 months (range 6-20 months). The plantaris tendon was histologically normal in 13/16 cases (81%). Inflammatory changes in the loose peritendinous connective tissue surrounding the plantaris tendon were evident in all cases. There was significant improvement in mean VAS scores (p

A strong electronic reconstruction resulting in a quenching of the Fe magnetic moments has recently been predicted to be at the origin of the giant magnetocaloric effect displayed by Fe2P-based materials. To verify this scenario, x-raymagnetic circular dichroism experiments have been carried out at the L edges of Mn and Fe for two typical compositions of the (Mn, Fe)(2)(P, Si, B) system. The dichroic absorption spectra of Mn and Fe have been measured in the vicinity of the first-order ferromagnetic transition. The experimental spectra are compared with first-principles calculations and charge-transfer multiplet simulations in order to derive the magnetic moments. Even though signatures of a metamagnetic behavior are observed either as a function of the temperature or the magnetic field, the similarity of the Mn and Fe moment evolution suggests that the quenching of the Fe moment is weaker than previously predicted.

The thermal-history dependence of the magnetoelastic transition in (Mn,Fe)2(P,Si) compounds has been investigated using high-resolution neutron diffraction. As-prepared samples display a large difference in paramagnetic-ferromagnetic (PM-FM) transition temperature compared to cycled samples. The initial metastable state transforms into a lower-energy stable state when the as-prepared sample crosses the PM-FM transition for the first time. This additional transformation is irreversible around the transition temperature and increases the energy barrier which needs to be overcome through the PM-FM transition. Consequently the transition temperature on first cooling is found to be lower than on subsequent cycles characterizing the so-called virgin effect. High temperature annealing can restore the cycled sample to the high-temperature metastable state, which leads to the recovery of the virgin effect. A model is proposed to interpret the formation and recovery of the virgin effect.

Worldwide speech-language therapy (SLT) students are educated in evidence-based practice (EBP). For students to use EBP in their future day-to-day clinical practice, they must value EBP as positive and must feel confident in using it. For curricula developers it is therefore important to know the impact their teaching has on these aspects of students' motivational beliefs. To develop and validate a measurement tool to assess EBP task value and self-efficacy in SLT students. A 20-item questionnaire was developed based on a review of the literature and an additional group interview with speech-language therapists. Face validity of the questionnaire was established using a Delphi panel consisting of six EBP lecturers. Dutch bachelor SLT students (n = 149) with a different level of EBP knowledge and skills filled in the newly developed questionnaire. Reliability (internal consistency) was assessed using Cronbach's alpha and internal validity using a principal component analysis (PCA). Construct validity was assessed by comparing the bachelor SLT student scores with a group of m students (n = 15) who were highly experienced in EBP. The PCA showed that the questionnaire consists of two components, representing EBP task value and self-efficacy, both with good reliability (Cronbach's α = 0.83 and 0.79, respectively). The hypothesis that master's students would score significantly higher on both components than bachelor SLT students was met. The study provides evidence on the internal consistency and construct validity of this questionnaire to evaluate EBP task value and self-efficacy in SLT students. As is common with new measures, more research is needed to evaluate further its psychometric properties

The importance and value of the principles of evidence-based practice (EBP) in the decision-making process is recognized by speech-language therapists (SLTs) worldwide and as a result curricula for speech-language therapy students incorporated EBP principles. However, the willingness actually to use EBP principles in their future profession not only depends on EBP knowledge and skills, but also on self-efficacy and task value students perceive towards EBP. To investigate the relation between EBP knowledge and skills, and EBP self-efficacy and task value in different year groups of Dutch SLT students. Students from three year groups filled in a tool that measured EBP knowledge and skills: the Dutch Modified Fresno (DMF). EBP self-efficacy and task value were assessed by using a 20-item questionnaire. Both tools were validated for this population. Mean scores for the three year groups were calculated and tested for group differences using a one-way analysis of variance (ANOVA) with a post-hoc Games-Howell procedure. With a multiple linear regression technique it was assessed whether EBP self-efficacy and task value predict learning achievement scores on the DMF. Other possible predictors included in the model were: level of prior education, standard of English, having had mathematics in prior education and the SLT study year. A total of 149 students filled in both measurement tools. Mean scores on EBP knowledge and skills were significantly different for the three year groups, with students who were further along their studies scoring higher on the DMF. Mean scores on the EBP self-efficacy and task value questionnaire were the same for the three year groups: all students valued EBP positive but self-efficacy was low in all groups. Of the possible predictors, only the year in which students study and EBP self-efficacy were significant predictors for learning achievements in EBP. Despite a significant increase in EBP knowledge and skills over the years as assessed by the DMF, the integrated EBP curriculum did not raise levels of EBP self-efficacy and task value. This lack of feeling competent might have an impact on students' willingness actually to use EBP. In curricula, therefore, there should be a focus on how to raise EBP self-efficacy in SLT students. This goes even beyond the educational department because a professional culture in which professionals are competent and confident EBP users would have a positive effect on EBP self-efficacy in students

Should we pool capacities or not? This is a question that one can regularly be confronted with in operations and service management. It is a question that necessarily requires a combination of queueing (as OR discipline) and simulation (as evaluative tool) and further steps for optimization. It will be illustrated that a combined approach (SimOR) of Simulation (techniques and tools) and classical Operations Research (queueing, linear programming and scheduling) can be most beneficial. First, an instructive example of parallel queues will be provided which shows the necessary and fruitful combination of queueing and simulation. Next, the combined approach will also be illustrated for the optimization of: call centers, checking-in at airports, blood platelet production, and train scheduling for railways. Whether we should pool or not is thus just one simple question for which this SimOR approach can be most fruitful if not necessary for practical optimization.

International audience; Intensive livestock farms emit large concentrations of NH3, most of which is deposited very close to the source. The presence of trees enhances the deposition. Rates to down wind forests can exceed 40 kg N ha-1. The steep gradient in large NH3 concentration and deposition at the edge of a downwind forest to background concentrations within a few hundred meters provides an ideal site to study the effect of different rates of N deposition on biological and chemical processes under similar environmental conditions. We have investigated the effect of different rates of NH3 deposition (62, 45, 24 and 5 kg NH3-N ha-1 y-1) on the flux of NO and N2O from soil in a mixed woodland downwind of a large poultry farm (160000 birds) in Scotland, which has been operating for about 40 years. Measurements were carried out for a 6 month period, with hourly NO flux measurements, daily N2O fluxes close to the farm and monthly at all sites and monthly cumulative wet and dry N deposition. The increased NH3 and NH4+ deposition to the woodland increased emissions of NO and N2O and soil available NH4+ and NO3- concentrations. Average NO and N2O fluxes measured 15, 25 and 45 m downwind of the farm were 111.2±41.1, 123.3±40.7, 38.3±28.8 µg NO-N m-2 h-1 and 9.9±7.5, 34.3±33.3 and 21.2±6.1 µg NO-N m-2 h-1, respectively. At the background site 270 m downwind the N2O flux was reduced to 1.75±2.1 µg N2O-N m-2 h-1. NO emissions were significantly influenced by seasonal and daily changes in soil temperature and followed a diurnal pattern with maximum emissions approximately 3h after noon. For N2O no consistent diurnal pattern was observed. Changes in soil moisture content had a less clear effect on the NO and N2O flux. On average the NO emissions expressed as a fraction of the elevated N deposited were 7.1% (at 15 m), 6% (at 25 m) and 2.3% (at 45 m) downwind of the farm, whereas for N2O the emissions were only 2.8% (at 15 m), 3% (at 25 m) and 3% (at 45 m) downwind. These emission fractions exceed the emission factor of 1% advised by the IPCC for N2O emissions resulting from atmospheric N deposition.

Three patients, men aged 20, 50 and 56 suffered from orthostatic intolerance and syncope for years, despite visits to many doctors. Medical history and cardiovascular reflex investigation revealed problems with the orthostatic blood pressure regulation, caused by initial orthostatic dysregulation, vasovagal syncope and pure autonomic failure, respectively. A structured medical history as well as blood pressure measurements in the supine and standing positions can reveal the diagnosis in many instances of syncope. After confirming the diagnosis, the first concern is a clear explanation of the underlying problems to the patient. Treatment with volume expansion should be considered

Le débat sur l'origine des Polynésiens et de leurs ancêtres présumés, les Lapita, continue dans toutes les disciplines de l'anthropologie. Il est clair que le meilleur moyen pour mettre en évidence l'origine d'une population est de s'intéresser à l'homme même à travers l'étude de son squelette. Les restes osseux sont rares mais peuvent être très parlant dans la mesure où l'on emploie une méthodologie appropriée. Cet article fait le point sur la recherche en anthropologie biologique des Polynésiens et discute quelques sérieux raccourcis méthodologiques et suppositions tacites. Il passe également en revue les principales théories sur l'origine biologique des insulaires du Pacifique puis s'intéresse en détail à deux aspects particuliers de la recherche actuelle : (1) les attributs morphologiques des squelettes considérés comme "polynésiens" et (2) les paramètres géographiques et chronologiques des échantillons utilisés dans l'analyse statistique. L'auteur s'interroge sur ce que l'on entend par les termes "polynésien", "mélanésien" et "lapita" et questionne si ces termes peuvent servir efficacement à la définition d'affinités biologiques. (Résumé d'auteur)

Gekeken werd naar de invloed van 2 zaaitijdstippen, 3 zaaizaadhoeveelheden en 2 rijenafstanden (25 en 50 cm)

Onderzoek werd uitgevoerd met crambe, bekergoudsbloem, akkermoerasbloem, goudsbloem, stompe wolfsmelk en koriander