50 research outputs found

    Using multiple short epochs optimises the stability of infant EEG connectivity parameters

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    Atypicalities in connectivity between brain regions have been implicated in a range of neurocognitive disorders. We require metrics to assess stable individual differences in connectivity in the developing brain, while facing the challenge of limited data quality and quantity. Here, we examine how varying core processing parameters can optimise the test-retest reliability of EEG connectivity measures in infants. EEG was recorded twice with a 1-week interval between sessions in 10- month-olds. EEG alpha connectivity was measured across different epoch lengths and numbers, with the phase lag index (PLI) and debiased weighted PLI (dbWPLI), for both whole-head connectivity and graph theory metrics. We calculated intra-class correlations between sessions for infants with sufficient data for both sessions (N’s = 19 – 41, depending on the segmentation method). Reliability for the whole brain dbWPLI was higher across many short epochs, whereas reliability for the whole brain PLI was higher across fewer long epochs. However, the PLI is confounded by the number of available segments. Reliability was higher for whole brain connectivity than graph theory metrics. Thus, segmenting available data into a high number of short epochs and calculating the dbWPLI is most appropriate for characterising connectivity in populations with limited availability of EEG data

    Analytical and experimental characterization of a miniature calorimetric sensor in pulsatile flow

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    The behaviour of a miniature calorimetric sensor, which is under consideration for catheter-based coronary artery flow assessment, is investigated in both steady and pulsatile tube flow. The sensor is composed of a heating element operated at constant power, and two thermopiles that measure flow-induced temperature differences over the sensor surface. An analytical sensor model is developed, which includes axial heat conduction in the fluid and a simple representation of the solid wall, assuming a quasi-steady sensor response to the pulsatile flow. To reduce the mathematical problem, described by a two-dimensional advection-diffusion equation, a spectral method is applied. A Fourier transform is then used to solve the resulting set of ordinary differential equations and an analytical expression for the fluid temperature is found. To validate the analytical model, experiments with the sensor mounted in a tube have been performed in steady and pulsatile water flow with various amplitudes and Strouhal numbers. Experimental results are generally in good agreement with theory and show a quasi-steady sensor response in the coronary flow regime. The model can therefore be used to optimize the sensor design for coronary flow assessment

    Real-time monitoring of infant theta power during naturalistic social experiences

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    Infant-directed speech and direct gaze are important social cues that shape infant’s attention to their parents. Traditional methods for probing their effect on infant attention involve a small number of pre-selected screen-based stimuli, which do not capture the complexity of real-world interactions. Here, we used neuroadaptive Bayesian Optimization (NBO) to search a large ‘space’ of different naturalistic social experiences that systematically varied in their visual (gaze direct to averted) and auditory properties (infant directed speech to nonvocal sounds). We measured oscillatory brain responses (relative theta power) during episodes of naturalistic social experiences in 57 typically developing 6- to 12-month-old infants. Relative theta power was used as input to the NBO algorithm to identify the naturalistic social context that maximally elicited attention in each individual infant. Results showed that individual infants were heterogeneous in the stimulus that elicited maximal theta with no overall stronger attention for direct gaze or infant-directed speech; however, individual differences in attention towards averted gaze were related to interpersonal skills and greater likelihood of preferring speech and direct gaze was observed in infants whose parents showed more positive affect. Our work indicates NBO may be a fruitful method for probing the role of distinct social cues in eliciting attention in naturalistic social contexts at the individual level

    A new look at population change and regional development in Aotearoa New Zealand

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    In New Zealand, population change is interlinked with regional development. Places growing in population attract regional investment, while regional investment—or lack thereof—can change migration patterns. However, to determine the appropriate response to population change for a community, it is important to understand that population change involves much more than “just” migration. Specifically, it involves interactions between the three components of population change: natural change (births minus deaths), net migration (international and internal) and population ageing (changing cohort size). For example, migration can be negative, but growth can be positive due to underlying natural increase or growth in cohort size. Responses need to differ, depending on these drivers. The goal of this article is to provide new insights into these interactions using data for 275 cities, towns and rural centres (hereafter “urban places”) in New Zealand for the period 1976 to 2013. The results show that natural change has been consistently positive for most urban places up to the present, although projections indicate that in the future this component will become negative across much of the country. At the same time, net migration shows considerable spatial variation, not only in terms of volume, but also direction (negative or positive), which differs markedly by age. A net gain of people of retirement age can offset a net loss of young adults to deliver overall growth, and vice-versa, but the two have very different implications for longer term growth. An analysis of the drivers of net migration using GIS and machine learning techniques provides an indication of the importance of economic conditions (land-use and access to markets), lifestyle, access to essential services (hospitals and education) and their interaction with age in regional change. The results show that population age is the best predictor of migration. Younger people are moving to cities for tertiary education and work and older people near or in retirement are moving to smaller lifestyle towns but also want to be close to amenities such as hospitals and international airports. The research also shows that natural lifestyle characteristics (landscape and climate), in combination with age are just as important as economic conditions for understanding migration. Regional development, such as infrastructure that helps business (ports and services) is important for the working age population but not necessarily the retirement age group. When regional development, age/life-cycle stage and lifestyle come together, such as in Queenstown and Tauranga, net migration gain is high

    Modulation of EEG theta by naturalistic social content is not altered in infants with family history of autism

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    Theta oscillations (spectral power and connectivity) are sensitive to the social content of an experience in typically developing infants, providing a possible marker of early social brain development. Autism is a neurodevelopmental condition affecting early social behaviour, but links to underlying social brain function remain unclear. We explored whether modulations of theta spectral power and connectivity by naturalistic social content in infancy are related to family history for autism. Fourteen-month-old infants with (family history; FH; N = 75) and without (no family history; NFH; N = 26) a first-degree relative with autism watched social and non-social videos during EEG recording. We calculated theta (4–5 Hz) spectral power and connectivity modulations (social–non-social) and associated them with outcomes at 36 months. We replicated previous findings of increased theta power and connectivity during social compared to non-social videos. Theta modulations with social content were similar between groups, for both power and connectivity. Together, these findings suggest that neural responses to naturalistic social stimuli may not be strongly altered in 14-month-old infants with family history of autism

    The impact of a cancer Survivorship Care Plan on gynecological cancer patient and health care provider reported outcomes (ROGY Care): study protocol for a pragmatic cluster randomized controlled trial

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    <p>Abstract</p> <p>Background</p> <p>There is a need for improvement of information provision and post-treatment care for cancer survivors. A Survivorship Care Plan (SCP) is recommended by the American Institute of Medicine and the Dutch Health Council, which is a summary of patients' course of treatment as a formal document, and includes recommendations for subsequent cancer surveillance, management of late effects, and strategies for health promotion. Until now, evidence on the effects of implementing the SCP in clinical practice is lacking. The rationale and study design of a pragmatic cluster randomized trial, aiming to assess the impact of SCP care in routine clinical practice, is presented.</p> <p>Methods/Design</p> <p>A web-based patient registration system 'Registrationsystem Oncological GYnecology' (ROGY) is used by gynecologists in the South of the Netherlands since 2006. A personalized SCP can automatically be generated out of ROGY. In this pragmatic cluster randomized controlled trial, 12 hospitals are randomized to either 'usual care' or 'SCP care'. In patients with 'usual care', the gynecologist provides care as usual. In patients with 'SCP care', information about the tumor stage and treatment is personally discussed with the patient and a document is handed to the patient. Prospectively, all patients diagnosed with endometrial or ovarian cancer in the participating hospitals will be approached for study participation. Patients will complete questionnaires after surgery, and before additional treatment, and after 6, 12, 18 and 24 months. In addition, health care providers will be asked their opinion about implementation of SCP care. Primary outcome is defined as patient satisfaction with information provision and care. Secondary outcomes are illness perception, health-related quality of life, health care use, prevalence, course and referral rate of survivors with psychosocial distress, and health care providers' evaluation of SCP care.</p> <p>Discussion</p> <p>The ROGY Care trial will help to gain insight into the impact of SCP care on patient reported outcomes, and on the evaluation of cancer survivors and health care providers of the different elements of the SCP. Therefore, results will contribute to efforts to improve quality of care for cancer survivors.</p> <p>Trial registration</p> <p>Trial Registration: <url>http://www.ClinicalTrials.gov</url>. Identifier: <a href="http://www.clinicaltrials.gov/ct2/show/NCT01185626">NCT01185626</a></p> <p>Medical Research Ethics Committee Reference Number: NL33429.008.10 Grant Reference Number: UVT2010-4743</p
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