840 research outputs found

    Do Regions with Entrepreneurial Neighbors Perform Better?: A Spatial Econometric Approach for German Regions

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    We use a neoclassical production function to analyze the effects of knowledge spillovers via entrepreneurship on economic performance of 337 German districts. To take the spatial dependence structure of the data into account, we estimate a spatial Durbin model. We highlight the importance of the choice of the appropriate weight matrix. We find positive knowledge spillover effects via entrepreneurship within a certain region. Between regions, entrepreneurship as a vehicle by which knowledge spills over and contributes to economic performance depends largely on the choice of the weight matrix. We see this as evidence for regionally bounded knowledge spillover effects via entrepreneurship.Entrepreneurship capital, regional output, spatial weight matrix

    Bestrijding van phytophthora, verlaagde dosering, rijenbehandeling

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    In 2007 is bij telers onderzoek uitgevoerd naar de mogelijkheden van rijenbehandeling in plaats van grondbehandeling tegen stengelbasisrot (Phytophthora cactorum) in aardbei. Op basis van deze kunstmatig besmette veldproef kan in plaats van een volveldsbehandeling ook een rijenbehandeling worden uitgevoerd met een derde van de hoeveelheid midde

    Chest computed tomography in severe bronchopulmonary dysplasia:Comparing quantitative scoring methods

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    Purpose: Bronchopulmonary dysplasia (BPD) is the most common complication of extreme preterm birth and structural lung abnormalities are frequently found in children with BPD. To quantify lung damage in BPD, three new Hounsfield units (HU) based chest-CT scoring methods were evaluated in terms of 1) intra- and inter-observer variability, 2) correlation with the validated Perth-Rotterdam-Annotated-Grid-Morphometric-Analysis (PRAGMA)-BPD score, and 3) correlation with clinical data. Methods: Chest CT scans of children with severe BPD were performed at a median of 7 months corrected age. Hyper- and hypo-attenuated regions were quantified using PRAGMA-BPD and three new HU based scoring methods (automated, semi-automated, and manual). Intra- and inter-observer variability was measured using intraclass correlation coefficients (ICC) and Bland-Altman plots. The correlation between the 4 scoring methods and clinical data was assessed using Spearman rank correlation. Results: Thirty-five patients (median gestational age 26.1 weeks) were included. Intra- and inter-observer variability was excellent for hyper- and hypo-attenuation regions for the manual HU method and PRAGMA-BPD (ICCs range 0.80–0.97). ICC values for the semi-automated HU method were poorer, in particular for the inter-observer variability of hypo- (0.22–0.71) and hyper-attenuation (-0.06–0.89). The manual HU method was highly correlated with PRAGMA-BPD score for both hyper- (ρs0.92, p &lt; 0.001) and hypo-attenuation (ρs0.79, p &lt; 0.001), while automated and semi-automated HU methods showed poor correlation for hypo- (ρs &lt; 0.22) and good correlation for hyper-attenuation (ρs0.72–0.74, p &lt; 0.001). Several scores of hyperattenuation correlated with the use of inhaled bronchodilators in the first year of life; two hypoattenuation scores correlated with birth weight. Conclusions: PRAGMA-BPD and the manual HU method have the best reproducibility for quantification of CT abnormalities in BPD.</p

    New developments of biofluid-based biomarkers for routine diagnosis and disease trajectories in frontotemporal dementia

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    Frontotemporal dementia (FTD) covers a spectrum of neurodegenerative disorders with different phenotypes, genetic backgrounds, and pathological states. Its clinicopathological diversity challenges the diagnostic process and the execution of clinical trials, calling for specific diagnostic biomarkers of pathologic FTD types. There is also a need for biomarkers that facilitate disease staging, quantification of severity, monitoring in clinics and observational studies, and for evaluation of target engagement and treatment response in clinical trials. This review discusses current FTD biofluid-based biomarker knowledge taking into account the differing applications. The limitations, knowledge gaps, and challenges for the development and implementation of such markers are also examined. Strategies to overcome these hurdles are proposed, including the technologies available, patient cohorts, and collaborative research initiatives. Access to robust and reliable biomarkers that define the exact underlying pathophysiological FTD process will meet the needs for specific diagnosis, disease quantitation, clinical monitoring, and treatment development

    Frontotemporal dementia, music perception and social cognition share neurobiological circuits:A meta-analysis

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    Frontotemporal dementia (FTD) is a neurodegenerative disease that presents with profound changes in social cognition. Music might be a sensitive probe for social cognition abilities, but underlying neurobiological substrates are unclear. We performed a meta-analysis of voxel-based morphometry studies in FTD patients and functional MRI studies for music perception and social cognition tasks in cognitively normal controls to identify robust patterns of atrophy (FTD) or activation (music perception or social cognition). Conjunction analyses were performed to identify overlapping brain regions. In total 303 articles were included: 53 for FTD (n = 1153 patients, 42.5% female; 1337 controls, 53.8% female), 28 for music perception (n = 540, 51.8% female) and 222 for social cognition in controls (n = 5664, 50.2% female). We observed considerable overlap in atrophy patterns associated with FTD, and functional activation associated with music perception and social cognition, mostly encompassing the ventral language network. We further observed overlap across all three modalities in mesolimbic, basal forebrain and striatal regions. The results of our meta-analysis suggest that music perception and social cognition share neurobiological circuits that are affected in FTD. This supports the idea that music might be a sensitive probe for social cognition abilities with implications for diagnosis and monitoring

    Diagnostic Accuracy of the Frontotemporal Dementia Consensus Criteria in the Late-Onset Frontal Lobe Syndrome

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    BACKGROUND/AIMS: We aimed to prospectively assess the diagnostic accuracy of the revised criteria for behavioural variant frontotemporal dementia (bvFTD) among subjects presenting with a frontal lobe syndrome in middle-late adulthood. METHODS: Patients were included based on a predominant behavioural clinical presentation, a Frontal Behavioural Inventory (FBI) score of ≥11 and/or a Stereotypy Rating Inventory (SRI) score of ≥10. At baseline, the fulfilment of the international consensus criteria for behavioural variant FTD (FTDC) was systematically recorded. The 2-year follow-up consensus diagnosis was used as the gold standard to calculate sensitivity and specificity of the FTDC criteria for possible and probable bvFTD. RESULTS: Two-year follow-up data were available for 116 patients (85%). Two-year follow-up consensus diagnoses consisted of probable/definite bvFTD (n = 27), other dementia (n = 30), psychiatric disorders (n = 46) and other neurological disorders (n = 13). Sensitivity for possible bvFTD was 85% (95% CI 70-95%) at a specificity of 27% (95% CI 19-37%). Sensitivity for probable bvFTD was 85% (95% CI 69-95%), whereas their specificity was 82% (95% CI 73-89%). CONCLUSIONS: We found a good diagnostic accuracy for FTDC probable bvFTD. However, the specificity for FTDC possible bvFTD was low. Our results reflect the symptomatic overlap between bvFTD, other neurological conditions and psychiatric disorders, and the relevance of adding neuroimaging to the diagnostic process

    Reducing Asthma Attacks in Children using Exhaled Nitric Oxide as a biomarker to inform treatment strategy:a randomised trial (RAACENO)

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    Acknowledgements The authors are indebted to the following persons who have helped deliver the RAACENO trial: Mrs J Wood and Mrs V Bell for implementation of protocol; Miss A Fraser for data coordination; colleagues in the Clinical Trials Unit in Aberdeen (Centre for Healthcare Randomised Trials, CHaRT); the Clinical Research Networks in East of England; the Scottish Primary Care Research Network; the local recruiting teams, participants and participant parents and care givers. The views and opinions expressed herein are those of the authors and do not necessarily reflect those of the Health Technology Assessment Programme, National Institute for Health Research (NIHR), NHS or the Department of Health. Funding {4} The trial is funded by the NIHR Efficacy and Mechanism Evaluation (EME) programme, project number 15-18-14. The funding body had no role in the design of the study, collection of data or the writing of this paper, nor will the funding body have a role in analysis, interpretation of data or in writing future manuscripts. Co-sponsor 1 is the University of Aberdeen, Foresterhill House Annexe, Foresterhill, Aberdeen, AB25 2ZB. Co-sponsor 2 is NHS Grampian, Foresterhill House Annexe, Foresterhill, Aberdeen, AB25 2ZB.Peer reviewedPublisher PD

    Performance of a new hand-held device for exhaled nitric oxide measurement in adults and children

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    BACKGROUND: Exhaled nitric oxide (NO) measurement has been shown to be a valuable tool in the management of patients with asthma. Up to now, most measurements have been done with stationary, chemiluminescence-based NO analysers, which are not suitable for the primary health care setting. A hand-held NO analyser which simplifies the measurement would be of value both in specialized and primary health care. In this study, the performance of a new electrochemical hand-held device for exhaled NO measurements (NIOX MINO) was compared with a standard stationary chemiluminescence unit (NIOX). METHODS: A total of 71 subjects (6–60 years; 36 males), both healthy controls and atopic patients with and without asthma were included. The mean of three approved exhalations (50 ml/s) in each device, and the first approved measurement in the hand-held device, were compared with regard to NO readings (Bland-Altman plots), measurement feasibility (success rate with 6 attempts) and repeatability (intrasubject SD). RESULTS: Success rate was high (≥ 84%) in both devices for both adults and children. The subjects represented a FE(NO )range of 8–147 parts per billion (ppb). When comparing the mean of three measurements (n = 61), the median of the intrasubject difference in exhaled NO for the two devices was -1.2 ppb; thus generally the hand-held device gave slightly higher readings. The Bland-Altman plot shows that the 95% limits of agreement were -9.8 and 8.0 ppb. The intrasubject median difference between the NIOX and the first approved measurement in the NIOX MINO was -2.0 ppb, and limits of agreement were -13.2 and 10.2 ppb. The median repeatability for NIOX and NIOX MINO were 1.1 and 1.2 ppb, respectively. CONCLUSION: The hand-held device (NIOX MINO) and the stationary system (NIOX) are in clinically acceptable agreement both when the mean of three measurements and the first approved measurement (NIOX MINO) is used. The hand-held device shows good repeatability, and it can be used successfully on adults and most children. The new hand-held device will enable the introduction of exhaled NO measurements into the primary health care
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