173 research outputs found

    Canopy uptake dominates nighttime carbonyl sulfide fluxes in a boreal forest

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    Nighttime vegetative uptake of carbonyl sulfide (COS) can exist due to the incomplete closure of stomata and the light independence of the enzyme carbonic anhydrase, which complicates the use of COS as a tracer for gross primary productivity (GPP). In this study we derived nighttime COS fluxes in a boreal forest (the SMEAR II station in Hyytiälä, Finland; 61°51′ N, 24°17′ E; 181 m a.s.l.) from June to November 2015 using two different methods: eddy-covariance (EC) measurements (FCOS-EC) and the radon-tracer method (FCOS-Rn). The total nighttime COS fluxes averaged over the whole measurement period were −6.8 ± 2.2 and −7.9 ± 3.8 pmol m−2 s−1 for FCOS-Rn and FCOS-EC, respectively, which is 33–38 % of the average daytime fluxes and 21 % of the total daily COS uptake. The correlation of 222Rn (of which the source is the soil) with COS (average R2  =  0.58) was lower than with CO2 (0.70), suggesting that the main sink of COS is not located at the ground. These observations are supported by soil chamber measurements that show that soil contributes to only 34–40 % of the total nighttime COS uptake. We found a decrease in COS uptake with decreasing nighttime stomatal conductance and increasing vapor-pressure deficit and air temperature, driven by stomatal closure in response to a warm and dry period in August. We also discuss the effect that canopy layer mixing can have on the radon-tracer method and the sensitivity of (FCOS-EC) to atmospheric turbulence. Our results suggest that the nighttime uptake of COS is mainly driven by the tree foliage and is significant in a boreal forest, such that it needs to be taken into account when using COS as a tracer for GPP

    Assisting children and youth with completing self-report instruments introduces bias : a mixed-method study that includes children and young people’s views

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    Many children and youth struggle to complete surveys and questionnaires by themselves. They are often assisted when are asked to give their opinion. From discussions with youth from the client council at a residential treatment facility for youths in The Netherlands, the notion emerged that interaction factors may impact the results of surveys, especially when sensitive topics are addressed. Using a mixed methods design, we explored the question if and how survey results are influenced by the presence of an assistant during assessment. 120 children and youth that reside at one of the treatment facilities of Koraal, a Dutch multi-site care facility, completed a survey about the perceived quality of care at the facility. They were randomly assigned to one of three conditions: (a) unassisted, (b) assisted by their care worker, or (c) assisted by a research assistant. The resulting scores in each condition were compared quantitatively. In successive focus groups with children and youth, the results and possible explanations were discussed

    The adaptation of self-report measures to the needs of people with intellectual disabilities : a systematic review

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    Persons with intellectual disabilities (ID) may have difficulties providing reliable and valid accounts of their personal experiences through self-report measures. The aim of the current study was to systematically review the peer-reviewed research literature on the adaptations needed to develop “ID-inclusive” self-report measures. A search of APA PsycInfo, PubMed, Web of Science, and Google Scholar identified 49 studies that met inclusion criteria. A GRADE-CERQual assessment was performed to determine the level of confidence in the review findings. One hundred sixty-one recommendations for the development of “ID-inclusive” self-report measures were extracted from 49 included studies. Recommendations were presented in a GRADE-CERQual Summary of Findings table, according to a five-stage model of instrument development. This review offers much-needed practical guidance for clinicians and researchers on how to develop “ID-inclusive” self-report measures. Recommendations for future research about self-report instrument development for use with people with ID are presented

    Inverse modelling of carbonyl sulfide: implementation, evaluation and implications for the global budget

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    Carbonyl sulfide (COS) has the potential to be used as a climate diagnostic due to its close coupling to the biospheric uptake of CO2 and its role in the formation of stratospheric aerosol. The current understanding of the COS budget, however, lacks COS sources, which have previously been allocated to the tropical ocean. This paper presents a first attempt at global inverse modelling of COS within the 4-dimensional variational data-assimilation system of the TM5 chemistry transport model (TM5-4DVAR) and a comparison of the results with various COS observations. We focus on the global COS budget, including COS production from its precursors carbon disulfide (CS2) and dimethyl sulfide (DMS). To this end, we implemented COS uptake by soil and vegetation from an updated biosphere model (Simple Biosphere Model-SiB4). In the calculation of these fluxes, a fixed atmospheric mole fraction of 500 pmol mol-1 was assumed. We also used new inventories for anthropogenic and biomass burning emissions. The model framework is capable of closing the COS budget by optimizing for missing emissions using NOAA observations in the period 2000-2012. The addition of 432 Gg a-1 (as S equivalents) of COS is required to obtain a good fit with NOAA observations. This missing source shows few year-to-year variations but considerable seasonal variations. We found that the missing sources are likely located in the tropical regions, and an overestimated biospheric sink in the tropics cannot be ruled out due to missing observations in the tropical continental boundary layer. Moreover, high latitudes in the Northern Hemisphere require extra COS uptake or reduced emissions. HIPPO (HIAPER Pole-to-Pole Observations) aircraft observations, NOAA airborne profiles from an ongoing monitoring programme and several satellite data sources are used to evaluate the optimized model results. This evaluation indicates that COS mole fractions in the free troposphere remain underestimated after optimization. Assimilation of HIPPO observations slightly improves this model bias, which implies that additional observations are urgently required to constrain sources and sinks of COS. We finally find that the biosphere flux dependency on the surface COS mole fraction (which was not accounted for in this study) may substantially lower the fluxes of the SiB4 biosphere model over strong-uptake regions. Using COS mole fractions from our inversion, the prior biosphere flux reduces from 1053 to 851 Gg a-1, which is closer to 738 Gg a-1 as was found by Berry et al. (2013). In planned further studies we will implement this biosphere dependency and additionally assimilate satellite data with the aim of better separating the role of the oceans and the biosphere in the global COS budget..</p

    The Activ8 activity monitor: Validation of posture and movement classification

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    Introduction: To set up and guide interventions with the aim to increase physical activity and lower sedentary behavior valid monitoring of physical behavior is essential. The aim of this study was to evaluate the validity of the single-uni

    Virtual reality cognitive-behavioural therapy versus cognitive-behavioural therapy for paranoid delusions:a study protocol for a single-blind multi-Centre randomised controlled superiority trial

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    Abstract Background Seventy per cent of patients with psychotic disorders has paranoid delusions. Paranoid delusions are associated with significant distress, hospital admission and social isolation. Cognitive-behavioural therapy for psychosis (CBTp) is the primary psychological treatment, but the median effect size is only small to medium. Virtual reality (VR) has a great potential to improve the effectiveness of CBTp. In a previous study, we found that VR based CBT (VRcbt) for paranoid delusions is superior to waiting list. As a next step, a direct comparison with CBTp is needed. The present study aims to investigate whether VRcbt is more effective and cost-effective than regular CBTp in treating paranoid delusions and improving daily life social functioning of patients with psychotic disorders. Methods A total of 106 patients with DSM-5 diagnosis of psychotic disorder and at least moderate level of paranoid ideations will be recruited for this multicentre randomized controlled trial (RCT). Patients will be randomized to either VRcbt or standard CBTp for paranoid delusions. VRcbt consists of maximum 16 sessions in virtual social situations that trigger paranoid ideations and distress, delivered in an 8–12 week time frame. Standard CBTp also consists of maximum 16 sessions including exposure and behavioural experiments, delivered in an 8–12 week time frame. The two groups will be compared at baseline, post-treatment and six months follow-up. Primary outcome is the level of paranoid ideations in daily life social situations, measured with ecological momentary assessments (EMA) at semi-random moments ten times a day during seven days, before and after treatment. Every session, participants and therapists will rate the level of paranoid ideation and global clinical impression. Discussion Comparison of VRcbt and CBTp will provide information about the relative (cost-) effectiveness of VRcbt for this population. VRcbt may become a preferred psychological treatment for paranoid delusions and social anxiety in patients with psychotic disorder. Trial registration Netherlands Trial Register, NL7758. Registered on 23 May 2019

    Which executive functioning deficits are associated with AD/HD, ODD/CD and comorbid AD/HD+ODD/CD?

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    Item does not contain fulltextThis study investigated (1) whether attention deficit/hyperactivity disorder (AD/HD) is associated with executive functioning (EF) deficits while controlling for oppositional defiant disorder/conduct disorder (ODD/CD), (2) whether ODD/CD is associated with EF deficits while controlling for AD/HD, and (3)~whether a combination of AD/HD and ODD/CD is associated with EF deficits (and the possibility that there is no association between EF deficits and AD/HD or ODD/CD in isolation). Subjects were 99~children ages 6–12 years. Three putative domains of EF were investigated using well-validated tests: verbal fluency, working memory, and planning. Independent of ODD/CD, AD/HD was associated with deficits in planning and working memory, but not in verbal fluency. Only teacher rated AD/HD, but not parent rated AD/HD, significantly contributed to the prediction of EF task performance. No EF deficits were associated with ODD/CD. The presence of comorbid AD/HD accounts for the EF deficits in children with comorbid AD/HD+ODD/CD. These results suggest that EF deficits are unique to AD/HD and support the model proposed by R. A. Barkley (1997).17 p
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