18,107 research outputs found

    Tailoring CanMEDS for training in Obstetrics and Gynaecology in the Netherlands

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    Scheele, F. [Promotor]Vleuten, C.P.M. van der [Promotor]Driessen, E.W. [Copromotor

    Flexure-based alignment mechanisms : design, development and application

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    For high accuracy alignment of optical components in optical instruments TNO TPD has developed dedicated,monolithic, flexure-based alignment mechanisms, which provide accuracies below 0.1 µm and 0.1 µrad as well asstabilities down to subnanometer stabilty per minute.High resolution, high stability alignment mechanisms consist of an adjustment mechanism and a locking device.Complex monolithic flexure-based mechanisms were designed to align specific degrees of freedom. They are realizedby means of spark erosion. The benefits of these mechanisms are no play, no hysteresis, high stiffness, a simplifiedthermal design and easy assemblage. The overall system can remain a passive system, which yields simplicity.An actuator is used for positioning. Locking after alignment is mandatory to guarantee sub-nanometer stability perminute. A proper design of the locking device is important to minimize drift during locking.The dedicated alignment mechanisms presented here are based on: (a) the results of an internal ongoing researchprogram on alignment and locking and (b) experience with mechanisms developed at TNO TPD for high precisionoptical instruments, which are used in e.g. a white light interferometer breadboard (Nulling) and an interferometer withpicometer resolution for ESA’s future cornerstone missions "DARWIN" and "GAIA"

    Entanglement of a qubit with a single oscillator mode

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    We solve a model of a qubit strongly coupled to a massive environmental oscillator mode where the qubit backaction is treated exactly. Using a Ginzburg-Landau formalism, we derive an effective action for this well known localization transition. An entangled state emerges as an instanton in the collective qubit-environment degree of freedom and the resulting model is shown to be formally equivalent to a Fluctuating Gap Model (FGM) of a disordered Peierls chain. Below the transition, spectral weight is transferred to an exponentially small energy scale leaving the qubit coherent but damped. Unlike the spin-boson model, coherent and effectively localized behaviors may coexist.Comment: 4 pages, 1 figure; added calculation of entanglement entrop

    Evidence of environmental strains on charge injection in silole based organic light emitting diodes

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    Using d. functional theory (DFT) computations, the authors demonstrated a substantial skeletal relaxation when the structure of 2,5-bis-[4-anthracene-9-yl-phenyl]-1,1-dimethyl-3,4-diphenyl-silole (BAS) is optimized in the gas-phase comparing with the mol. structure detd. from monocrystal x-ray diffraction. The origin of such a relaxation is explained by a strong environmental strains induced by the presence of anthracene entities. Also, the estn. of the frontier orbital levels showed that this structural relaxation affects mainly the LUMO that is lowered of 190 meV in the gas phase. To check if these theor. findings would be confirmed for thin films of BAS, the authors turned to UV photoemission spectroscopy and/or inverse photoemission spectroscopy and electrooptical measurements. The study of the c.d. or voltage and luminance or voltage characteristics of an ITO/PEDOT/BAS/Au device clearly demonstrated a very unusual temp.-dependent behavior. Using a thermally assisted tunnel transfer model, this behavior likely originated from the variation of the electronic affinity of the silole deriv. with the temp. The thermal agitation relaxes the mol. strains in thin films as it is shown when passing from the cryst. to the gas phase. The relaxation of the intramol. thus induces an increase of the electronic affinity and, as a consequence, the more efficient electron injection in org. light-emitting diodes

    Superfluid-insulator transition of the Josephson junction array model with commensurate frustration

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    We have studied the rationally frustrated Josephson-junction array model in the square lattice through Monte Carlo simulations of (2+1)(2+1)D XY-model. For frustration f=1/4f=1/4, the model at zero temperature shows a continuous superfluid-insulator transition. From the measurement of the correlation function and the superfluid stiffness, we obtain the dynamical critical exponent z=1.0z=1.0 and the correlation length critical exponent ν=0.4±0.05\nu=0.4 \pm 0.05. While the dynamical critical exponent is the same as that for cases f=0f=0, 1/2, and 1/3, the correlation length critical exponent is surprisingly quite different. When f=1/5f=1/5, we have the nature of a first-order transition.Comment: RevTex 4, to appear in PR

    A group processes approach to antiscience beliefs and endorsement of “alternative facts”

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    The global spread of antiscience beliefs, misinformation, fake news, and conspiracy theories is posing a threat to the well-being of individuals and societies worldwide. Accordingly, research on why people increasingly doubt science and endorse “alternative facts” is flourishing. Much of this work has focused on identifying cognitive biases and individual differences. Importantly, however, the reasons that lead people to question mainstream scientific findings and share misinformation are also inherently tied to social processes that emerge out of divisive commitments to group identities and worldviews. In this special issue, we focus on the important and thus far neglected role of group processes in motivating science skepticism. The articles that feature in this special issue cover three core areas: the group-based roots of antiscience attitudes; the intergroup dynamics between science and conspiratorial thinking; and finally, insights about science denial related to the COVID-19 pandemic. Across all articles, we highlight the role of worldviews, identities, norms, religion, and other inter- and intragroup processes that shape antiscientific attitudes. We hope that this collection will inspire future research endeavors that take a group processes approach to the social psychological study of science skepticism. </jats:p

    Need for a primary care based intervention for fear of cancer recurrence:Conclusions from the blanket trial

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    Background More than half of cancer survivors experience fear of cancer recurrence (FCR). There has been a call for easily accessible, inexpensive interventions for moderate FCR to complement existing specialized care. In the randomized BLANKET trial, we investigated the effectiveness of a short, primary care intervention for FCR. We report on the potential of the intervention and the suitability of primary care to offer this intervention. Methods The BLANKET trial is a cluster randomized controlled trial with change in FCR severity (severity subscale of the Fear of Cancer Recurrence Inventory) as its main outcome. Participating general practitioners invited all patients who completed successful curative cancer treatment between 3 months and 10 years ago. We report effect measures, outcome of our recruitment strategy, intervention uptake, reasons not to participate, and experiences with the intervention. Results Sixty-two of 1368 (4.5%) invited cancer survivors participated. Main reported reasons not to participate were not experiencing FCR and not wanting help. Owing to the low participation, we could not robustly evaluate the intervention's effectiveness. Indicatively, in the intention-to-treat analysis, FCR severity decreased from T0 to T1 by 2.7 points (standard deviation [SD] = 4.7) in the intervention group (n = 27) and 1.8 points (SD = 3.6) in the control group (n = 18). In the per-protocol analysis, the decreases were 3.5 points (SD = 4.5) and 0.7 points (SD = 2.7), respectively. Conclusion Although the prevalence of FCR and the need for help for FCR are high according to the literature, the uptake of our primary care–based intervention was low. Although the intervention shows potential, alternative delivery routes need to be explored because of the low number of patients who need help for FCR per primary care practice. We recommend additional research on the impact of FCR, on which patients require and desire help, and on what kind of intervention and setting are fitting for what patients
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