Prediction and measurement of the size-dependent stability of fluorescence in diamond over the entire nanoscale

Fluorescent defects in non-cytotoxic diamond nanoparticles are candidates for qubits in quantum computing, optical labels in biomedical imaging and sensors in magnetometry. For each application these defects need to be optically and thermodynamically stable, and included in individual particles at suitable concentrations (singly or in large numbers). In this letter, we combine simulations, theory and experiment to provide the first comprehensive and generic prediction of the size, temperature and nitrogen-concentration dependent stability of optically active NV defects in nanodiamonds.Comment: Published in Nano Letters August 2009 24 pages, 6 figure

The CIPRUS study, a nurse-led psychological treatment for patients with undifferentiated somatoform disorder in primary care: study protocol for a randomised controlled trial

Background: Up to a third of patients presenting medically unexplained physical symptoms in primary care may have a somatoform disorder, of which undifferentiated somatoform disorder (USD) is the most common type. Psychological interventions can reduce symptoms associated with USD and improve functioning. Previous research has either been conducted in secondary care or interventions have been provided by general practitioners (GPs) or psychologists in primary care. As efficiency and cost-effectiveness are imperative in primary care, it is important to investigate whether nurse-led interventions are effective as well. The aim of this study is to examine the effectiveness and cost-effectiveness of a short cognitive behavioural therapy (CBT)-based treatment for patients with USD provided by mental health nurse practitioners (MHNPs), compared to usual care. Methods: In a cluster randomised controlled trial, 212 adult patients with USD will be assigned to the intervention or care as usual. The intervention group will be offered a short, individual CBT-based treatment by the MHNP in addition to usual GP care. The main goal of the intervention is that patients become less impaired by their physical symptoms and cope with symptoms in a more effective way. In six sessions patients will receive problem-solving treatment. The primary outcome is improvement in physical functioning, measured by the physical component summary score of the RAND-36. Secondary outcomes include health-related quality of life measured by the separate subscales of the RAND-36, somatization (PHQ-15) and symptoms of depression and anxiety (HADS). Problem-solving skills, health anxiety, illness perceptions, coping, mastery and working alliance will be assessed as potential mediators. Assessments will be done at 0, 2, 4, 8 and 12 months. An economic evaluation will be conducted from a societal perspective with quality of life as the primary outcome measure assessed by the EQ-5D-5L. Health care, patient and lost productivity costs will be assessed with the Tic-P. Discussion: We expect that the intervention will improve physical functioning and is cost-effective compared to usual care. If so, more patients might successfully be treated in general practice, decreasing the number of referrals to specialist care. Trial registration: Dutch Trial Registry, identifier: NTR4686, Registered on 14 July 2014. © 2017 The Author(s)

Gender differences in conversation topics, 1922–1990

Gender differences in conversation topics were first systematically studied in 1922 by Henry Moore, who theorized that the gender differences in topic choice he observed in a field observation study would persist over time, as they were manifestations of men's and women's “original natures.” In this paper, I report a 1990 replication of Moore's study, in which similar but smaller gender differences in topic choice are found. In order to explore further the apparent trend toward smaller gender differences, reports of quantitative observation studies conducted between 1922 and 1990 are examined. Other explanations besides change over time—such as variations in conversation setting and audience, target populations, and researcher's intentions—may account for the decline in gender differences in topic choice. Social influences are seen more clearly in the discourse about gender differences in conversation than in gender differences in conversation topics themselves.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/45599/1/11199_2004_Article_BF00289744.pd

Investigation of the dynamics of coupled cantilever arrays on a micro and macro scale with applications to AFM

Since the invention of atomic force microscopy (AFM) researchers have been trying to increase imaging speed. One method is to bring multiple cantilever probes together in close proximity to form an array. By using each probe independently, multiple points on a sample can be imaged simultaneously. AFM arrays have been developed and produced by the Rangelow research group under the PRONANO project at Technische Universität Ilmenau [1]. These arrays are fabricated from multi-layer silicon beams and have bimetallic heater actuators and piezo-resistive sensors incorporated into each probe, allowing for individual actuation and sensing (Figure 1). Due to the close proximity of the cantilevers, the system response exhibits coupling phenomena (mechanical, electrical, thermal and fluidic). The way this coupling affects the dynamics of each beam and the system as a whole is not fully understood

Tip Motion-Sensor Signal Relation for a Composite SPM/SPL Cantilever

An array of microbeams is a promising approach to increase the throughput of scanning probe microscopes and lithography. This concept requires integrated sensors and actuators which enable individual measurement and control. Thus, existing models for single beams need to be reassessed in view of its applicability for arrays, which involve additional physical interactions and a varying geometry along the beam's length. This paper considers a single composite microbeam, which is excited by a thermal actuator and its displacement is measured by a piezoresistive sensor. We derive a model that incorporates the beam's composite structure, varying geometry along its length, its thermal coupling for actuation, and thermoelastic damping. Subsequently, the influence of the beam's geometry on its eigenmodes and frequencies is analyzed in far and close proximity operation to a surface. We observe parametric excitation phenomena of multiple integers of the fundamental excitation frequency, which originates from the geometrical composition of the beam. Furthermore, we observe that the so far constant assumed factor to convert the sensor signal to the beam's displacement depends on the dissipated power within the actuator, as well as on the dynamic behavior of the system, and thus is not constant