346 research outputs found

    Microstructure and Rheology of Lamellar Liquid Crystalline Phases

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    We have investigated the microstructure and rheological properties of ternary surfactant mixtures in a salt solution. The surfactants were 6% sodium 4-dodecylbenzenesulfonate, 3% C13-15 ethoxylated alcohol with seven ethylene oxide (EO) units and 1% C13-15 ethoxylated alcohol with 2, 4, 7, 9, 11, 14, 20, or 25 EO units. The salt solution was 10% nitrilotriacetate·H2O. Microstructural investigations (electron microscopy, light microscopy, confocal laser microscopy, conductivity measurements, and centrifugation) show that at rest the samples containing the surfactant with 2 EO to 9 EO units are dispersions of lamellar droplets (curved surfactant bilayers). The samples containing the surfactant with 11 EO to 25 EO units show a continuous lamellar structure (sheets of surfactant bilayers) with a small amount of lamellar droplets present. The change in several rheological parameters reflects this change in microstructure. The power law index from flow experiments at low shear rates changes from 0.1 for the lamellar dispersions to 0.4 for the continuous lamellar phases. Similar changes are observed in shear modulus and in the limiting strain for linear viscoelastic behavior. The continuous lamellar phase is converted to droplets by shearing at rates above 1 s-1. The continuous lamellar structures will recover in about a week when the samples are allowed to relax. The nature of the droplets is highly dynamic. Confocal laser microscopy shows small fluctuations in droplet shape on a time scale of about 100 s. This time coincides with a characteristic time of around 100 s pertaining to a (shallow) peak in G''

    Brijvoedering of droogvoedering aan gespeende biggen?

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    Gespeende biggen die brij verstrekt krijgen met behulp van een volautomatische brijvoerinstallatie hebben een duidelijk slechtere voederconversie dan biggen die onbeperkt droogvoer krijgen. Voervermorsing is hiervan vermoedelijk de oorzaak

    Mass-Varying Neutrinos from a Variable Cosmological Constant

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    We consider, in a completely model-independent way, the transfer of energy between the components of the dark energy sector consisting of the cosmological constant (CC) and that of relic neutrinos. We show that such a cosmological setup may promote neutrinos to mass-varying particles, thus resembling a recently proposed scenario of Fardon, Nelson, and Weiner (FNW), but now without introducing any acceleronlike scalar fields. Although a formal similarity of the FNW scenario with the variable CC one can be easily established, one nevertheless finds different laws for neutrino mass variation in each scenario. We show that as long as the neutrino number density dilutes canonically, only a very slow variation of the neutrino mass is possible. For neutrino masses to vary significantly (as in the FNW scenario), a considerable deviation from the canonical dilution of the neutrino number density is also needed. We note that the present `coincidence' between the dark energy density and the neutrino energy density can be obtained in our scenario even for static neutrino masses.Comment: 8 pages, minor corrections, two references added, to apear in JCA

    Feasibility and reliability of PRISMA-Medical for specialty-based incident analysis

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    Aims and objectives: In this study, the feasibility and reliability of the Prevention Recovery Information System for Monitoring and Analysis (PRISMA)-Medical method for systematic, specialty-based analysis and classification of incidents in the neonatal intensive care unit (NICU) were determined. Methods: After the introduction of a Neonatology System for Analysis and Feedback on Medical Events (NEOSAFE) in eight tertiary care NICUs and one paediatric surgical ICU, PRISMA-Medical was started to be used to identify root causes of voluntary reported incidents by multidisciplinary unit patient safety committees. Committee members were PRISMA-trained and familiar with the department and its processes. In this study, the results of PRISMA-analysis of incidents reported during the first year are described. At t¿=¿3 months and t¿=¿12 months after introduction, test cases were performed to measure agreement at three levels of root cause classification using PRISMA-Medical. Inter-rater reliability was determined by calculating generalised ¿ values for each level of classification. Results: During the study period, 981 out of 1786 eligible incidents (55%) were analysed for underlying root causes. In total, 2313 root causes were identified and classified, giving an average of 2.4 root causes for every incident. Although substantial agreement (¿ 0.70–0.81) was reached at the main level of root cause classification of the test cases (discrimination between technical, organisational and human failure) and agreement among the committees at the second level (discrimination between skill-based, rule-based and knowledge-based errors) was acceptable (¿ 0.53–0.59), discrimination between rule-based errors (the third level of classification) was more difficult to assess (¿ 0.40–0.47). Conclusion: With some restraints, PRISMA-Medical proves to be both feasible and acceptably reliable to identify and classify multiple causes of medical events in the NICU

    Optimal anatomical location for needle chest decompression for tension pneumothorax:A multicenter prospective cohort study

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    Objective: Tension Pneumothorax (TP) can occur as a potentially life threatening complication of chest trauma. Both the 2nd intercostal space in the midclavicular line (ICS2-MCL) and the 4th/5th intercostal space in the anterior axillary line (ICS 4/5-AAL) have been proposed as preferred locations for needle decompression (ND) of a TP. In the present study we aim to determine chest wall thickness (CWT) at ICS2-MCL and ICS4/5-AAL in normal weight-, overweight- and obese patients, and to calculate theoretical success rates of ND for these locations based on standard catheter length. Methods: We performed a prospective multicenter study of a convenience sample of adult patients presenting in Emergency Departments (ED) of 2 university hospitals and 6 teaching hospitals participating in the XXX consortium. CWT was measured bilaterally in ISC2-MCL and ISC4/5-AAL with point of care ultrasound (POCUS) and hypothetical success rates of ND were calculated for both locations based on standard equipment used for ND. Results: A total of 392 patients was included during a 2 week period. Mean age was 51 years (range 18-89), 52% was male and mean BMI was 25.5 (range 16.3-45.0). Median CWT was 26 [IQR 21-32] (range 9-52) mm in ISC2-MCL, and 26 [21-33] (range 10-78) mm in ICS4/5-AAL (p30, p=0.016 subjects, but not in subjects with a normal BMI. Hypothetical failure rates for 45mm Venflon and 50mm Angiocatheter were 2.5% and 0.8% for ICS2-MCL and 6.2% and 2.5% for ISC4/5-AAL (p=0.016 and p=0.052 respectively). Conclusion: In overweight- and obese subjects, the chest wall is thicker in ICS 4/5-AAL than in ICS2-MCL and theoretical chances of successful needle decompression of a tension pneumothorax are significantly higher in ICS2-MCL compared to ICS 4/5-AAL. (C) 2020 The Author(s). Published by Elsevier Ltd

    Specialty-based, voluntary incident reporting in neonatal intensive care: description of 4846 incident reports

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    OBJECTIVES: To examine the characteristics of incidents reported after introduction of a voluntary, non-punitive incident reporting system for neonatal intensive care units (NICUs) in the Netherlands; and to investigate which types of reported incident pose the highest risk to patients in the NICU. DESIGN: Prospective multicentre survey. METHODS: Voluntary, non-punitive incident reporting was introduced in eight level III NICUs and one paediatric surgical ICU. An incident was defined as any unintended event which (could have) reduced the safety margin for the patient. Multidisciplinary, unit-based patient safety committees systematically collected and analysed incident reports, and assigned risk scores to each reported incident. Data were centrally collected for specialty-based analysis. This paper describes the characteristics of incidents reported during the first year. Bivariate logistic regression analysis was conducted to identify high-risk incident categories. RESULTS: There were 5225 incident reports on 3859 admissions, of which 4846 were eligible for analysis. Incidents with medication were most frequently reported (27%), followed by laboratory (10%) and enteral nutrition (8%). Severe harm was described in seven incident reports, and moderate harm in 63 incident reports. Incidents involving mechanical ventilation and blood products were most likely to be assigned high-risk scores, followed by those involving parenteral nutrition, intravascular lines and medication dosing errors. CONCLUSIONS: Incidents occur much more frequently in Dutch NICUs than has been previously observed, and their impact on patient morbidity is considerable. Reported incidents concerning mechanical ventilation, blood products, intravascular lines, parenteral nutrition and medication dosing errors pose the highest risk to patients in the NIC

    The value of competitive employment:In-depth accounts of people with intellectual disabilities

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    BackgroundIncreasing the societal participation of people with intellectual disabilities via competitive employment requires a full understanding of what this means to them. This paper aims to provide an in‐depth examination of the lived experiences of people with intellectual disabilities in competitive employment.MethodInterviews were conducted with six participants with mild intellectual disability or borderline functioning and good verbal communication skills. Interviews were analysed according to the guidelines of interpretative phenomenological analysis (IPA). Member checks were conducted.ResultsAnalysis yielded three main themes: (a) Building on my life experiences, (b) My place at work and (c) Being a valuable member of society, like everyone else.ConclusionsCompetitive employment could make a substantial contribution to the sense of belonging to society and quality of life of people with intellectual disabilities. Nevertheless, they must cope with stigma‐related obstacles and feelings of being dependent on others in the work environment

    The neighbourhood environment and use of neighbourhood resources in older adults with and without lower limb osteoarthritis:results from the Hertfordshire Cohort Study

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    This study aimed to examine the associations of perceptions of neighbourhood cohesion and neighbourhood problems and objectively measured neighbourhood deprivation with the use of neighbourhood resources by older adults with and without lower limb osteoarthritis (LLOA), and to assess whether these relationships are stronger in older persons with LLOA than in those without the condition. Data from the Hertfordshire Cohort Study were used. American College of Rheumatology classification criteria were used to diagnose clinical LLOA (knee and/or hip osteoarthritis). Use of neighbourhood resources was assessed using the Home and Community Environment instrument. Participants were asked about their perceptions of neighbourhood cohesion and neighbourhood problems. Objective neighbourhood deprivation was assessed using the Index of Multiple Deprivation score based on 2010 census data. Of the 401 participants (71–80 years), 74 (18.5 %) had LLOA. The neighbourhood measures were not significantly associated with use of resources in the full sample. A trend for a negative association between use of public transport and perceived neighbourhood problems was observed in participants with LLOA (OR = 0.77, 99 % CI = 0.53–1.12), whereas a trend for a positive association between perceived neighbourhood problems and use of public transport was found in participants without LLOA (OR = 1.18, 99 % CI = 1.00–1.39). The perception of more neighbourhood problems seems only to hinder older adults with LLOA to make use of public transport. Older adults with LLOA may be less able to deal with neighbourhood problems and more challenging environments than those without the condition

    Severe acute respiratory infection caused by swine influenza virus in a child necessitating extracorporeal membrane oxygenation (ECMO), the Netherlands, October 2016.

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    In October 2016, a severe infection with swine influenza A(H1N1) virus of the Eurasian avian lineage occurred in a child with a previous history of eczema in the Netherlands, following contact to pigs. The patient's condition deteriorated rapidly and required life support through extracorporeal membrane oxygenation. After start of oseltamivir treatment and removal of mucus plugs, the patient fully recovered. Monitoring of more than 80 close unprotected contacts revealed no secondary cases
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