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1.
J Crit Care ; 69: 153992, 2022 06.
Article in English | MEDLINE | ID: mdl-35104693

ABSTRACT

PURPOSE: Critically ill COVID-19 patients have an increased risk of developing pulmonary embolism (PE). Diagnosis of PE by point-of-care ultrasound (POCUS) might reduce the need for computed tomography pulmonary angiography (CTPA), while decreasing time-to-diagnosis. MATERIALS & METHODS: This prospective, observational study included adult ICU patients with COVID-19. Multi-organ (lungs, deep vein, cardiac) POCUS was performed within 24 h of CTPA, looking for subpleural consolidations, deep venous thrombosis (DVT), and right ventricular strain (RVS). We reported the scan time, and calculated diagnostic accuracy measures for these signs separately and in combination. RESULTS: 70 consecutive patients were included. 23 patients (32.8%) had a PE. Median scan time was 14 min (IQR 11-17). Subpleural consolidations' diagnostic accuracy was: 42.9% (95%CI [34.1-52.0]). DVT's and RVS' diagnostic accuracy was: 75.6% (95%CI [67.1-82.9]) and 74.4% (95%CI [65.8-81.8]). Their sensitivity was: 24.0% (95%CI [9.4-45.1]), and 40.0% (95%CI [21.3-61.3]), while their specificity was: 88.8% (95%CI [80.8-94.3]), and: 83.0% (95%CI [74.2-89.8]), respectively. Multi-organ POCUS sensitivity was: 87.5% (95%CI [67.6-97.3]), and specificity was: 25% (95%CI [16.9-34.7]). CONCLUSIONS: Multi-organ rather than single-organ POCUS can be of aid in ruling out PE in critically ill COVID-19 and help select patients for CTPA. In addition, finding RVS can make PE more likely, while a DVT would preclude the need for a CTPA. REGISTRATION: www.trialregister.nl: NL8540.


Subject(s)
COVID-19 , Pulmonary Embolism , Venous Thrombosis , Adult , COVID-19/complications , COVID-19/diagnostic imaging , Critical Illness , Humans , Point-of-Care Systems , Prospective Studies , Pulmonary Embolism/diagnostic imaging , Pulmonary Embolism/etiology , Venous Thrombosis/diagnostic imaging
3.
BMC Public Health ; 18(1): 1109, 2018 Sep 10.
Article in English | MEDLINE | ID: mdl-30200919

ABSTRACT

BACKGROUND: To improve the availability and accessibility of healthier food and drinks in schools, sports and worksites canteens, national Guidelines for Healthier Canteens were developed by the Netherlands Nutrition Centre. Until now, no tool was available to monitor implementation of these guidelines. This study developed and assessed the content validity and usability of an online tool (the 'Canteen Scan') that provides insight into and directions for improvement of healthier food products in canteens. METHODS: The Canteen Scan was developed using a three-step iterative process. First, preliminary measures and items to evaluate adherence to the guidelines were developed based on literature, and on discussions and pre-tests with end-users and experts from science, policy and practice. Second, content validity of a paper version of the Canteen Scan was assessed among five end-users. Third, the online Canteen Scan was pilot tested among end-users representing school canteens. Usability was measured by comprehensibility, user-friendliness, feasibility, time investment, and satisfaction. RESULTS: The content validity of the Canteen Scan was ensured by reaching agreement between stakeholders representing science, policy and practice. The scan consists of five elements: 1) basic conditions (e.g. encouragement to drink water and availability of policy regarding the guidelines), 2) product availability offered on displays (counter, shelf) and 3) in vending machines, 4) product accessibility (e.g. promotion and placement of products), and 5) an overall score based on the former elements and tailored feedback for creating a healthier canteen. The scan automatically classifies products into healthier or less healthy products. Pilot tests indicated good usability of the tool, with mean scores of 4.0-4.6 (5-point Likert scale) on the concepts comprehensibility, user-friendliness and feasibility. CONCLUSION: The Canteen Scan provides insight into the extent to which canteens meet the Dutch Guidelines for Healthier Canteens. It also provides tailored feedback to support adjustments towards a healthier canteen and with the scan changes over time can be monitored. Pilot tests show this tool to be usable in practice.


Subject(s)
Diet, Healthy , Food Services/standards , Guideline Adherence/organization & administration , Guidelines as Topic , Online Systems , Humans , Netherlands , Pilot Projects , Reproducibility of Results
4.
J Vis (Tokyo) ; 21(1): 39-55, 2018.
Article in English | MEDLINE | ID: mdl-29367828

ABSTRACT

ABSTRACT: The interaction between a propeller and its self-induced vortices originating on the ground is investigated in a scaled experiment. The velocity distribution in the flow field in two different planes containing the self-induced vortices is measured by particle image velocimetry (PIV). These planes are a wall-parallel plane in close proximity to the ground and a wall-normal plane just upstream of the propeller. Based on the visualization of the flow field in these two planes, the occurrence of ground vortices and its domain boundary are analysed. The elevation of the propeller from the ground and the thrust of the propeller are two parameters that determine the occurrence of ground vortices. The main features of the propeller inflow in the presence of the ground vortices are highlighted. Moreover, the analysis of the non-uniform inflow in the azimuthal direction shows that with increasing the propeller thrust coefficient and decreasing the elevation of the propeller above the ground, the variation of the inflow angle of the blade increases.

5.
J Vis (Tokyo) ; 21(1): 117-132, 2018.
Article in English | MEDLINE | ID: mdl-29367829

ABSTRACT

ABSTRACT: During the ground operation of aircraft, the interaction between the propulsor-induced flow field and the ground may lead to the generation of ground vortices. Utilizing numerical approaches, the source of vorticity entering ground vortices is investigated. The results show that the production of wall-parallel components of vorticity has a strong contribution from the wall-parallel components of the pressure gradient on the wall, which is generated by the action of the propulsor. This mechanism is a supplementation for the vorticity transported from the far-field boundary layer, which has been assumed the main vorticity source in a number of previous publications. Furthermore, the quantitative prediction of the occurrence of ground vortices is performed from the numerical results. As the distance of the propeller form the ground decreases, and as the thrust of the propeller increases, ground vortices are generated from the ground and enter the propeller. In addition, the vortices which exist near the ground but does not enter the propeller plane are observed and visualized by three-dimensional data.

6.
J Sports Sci ; 28(13): 1451-8, 2010 Nov.
Article in English | MEDLINE | ID: mdl-20960363

ABSTRACT

Wooden racket paddles were modified with rubber and carbon fibre laminates and their differences tested in terms of flexural, damping, and coefficient of restitution properties. Four rackets types were designed: a wood reference, wood with rubber, carbon fibre 0°, and carbon fibre 90°. Seven expert and eight intermediate tennis players tested the rackets. To determine which of the four rackets suited the players best, we asked the players to compare the rackets two by two. After each pair tested, participants had to fill out a 4-item questionnaire in which different aspects of the rackets' performance were judged. The most preferred racket was the 0° carbon fibre racket, followed by the 90° carbon fibre racket, the wood racket and, finally, the 1-mm rubber racket. Thus, rackets with the highest stiffness, least damping, and highest coefficient of restitution were the most preferred. Interestingly, although experts and intermediate players overall judged the rackets in very similar ways according to force, vibration, and control, they were sensitive to quite different physical characteristics of the rackets.


Subject(s)
Carbon , Consumer Behavior , Sports Equipment , Tennis , Wood , Athletes , Equipment Design , Humans
7.
J Hum Nutr Diet ; 23(6): 601-8, 2010 Dec.
Article in English | MEDLINE | ID: mdl-20609036

ABSTRACT

BACKGROUND: The prevalence of the metabolic syndrome is increasing, especially in young individuals. Most of the previous studies that have investigated the association between dietary fibre intake and the metabolic syndrome are cross-sectional or of short duration, and their results are inconsistent. The present study investigated whether dietary fibre intake during adolescence has a protective effect on developing the metabolic syndrome as an adult. METHODS: Data on dietary intake and metabolic syndrome components were derived from a healthy sample of 174 men and 194 women who were followed-up from the age of 13 years onwards in the Amsterdam Growth and Health Longitudinal Study. Data were analysed with use of generalised estimating equations and linear regression analyses. RESULTS: The mean dietary fibre intake was 9.9 g/4.0 MJ (1000 kcal) during adolescence and 10.8 g/4.0 MJ (1000 kcal) at age 36 years. The prevalence of the metabolic syndrome at age 36 years was 10.1%. No differences were found in the time-course of dietary fibre intake between subjects with and those without the metabolic syndrome or its components. Dietary fibre intake during adolescence was not related to the components of the metabolic syndrome at age 36 years, except for an inverse relationship with waist circumference, where a gram/4.0 MJ (1000 kcal) higher fibre intake was associated with a 0.44 cm smaller waist circumference (P = 0.03, 95% CI -0.85 to -0.04). CONCLUSIONS: The present study found no association between dietary fibre intake and the metabolic syndrome in young adults. High fibre intake, however, was inversely associated with waist circumference.


Subject(s)
Dietary Fiber/administration & dosage , Metabolic Syndrome/epidemiology , Adolescent , Blood Pressure , Diet , Exercise , Female , Follow-Up Studies , Humans , Linear Models , Lipids/blood , Longitudinal Studies , Male , Metabolic Syndrome/diagnosis , Netherlands/epidemiology , Waist Circumference
8.
Eur J Clin Nutr ; 63(4): 536-42, 2009 Apr.
Article in English | MEDLINE | ID: mdl-18270523

ABSTRACT

BACKGROUND/OBJECTIVES: Coffee consumption has been postulated to decrease the risk of diabetes mellitus type II. The long-term effects of coffee consumption on the metabolic syndrome (MS) and its components are unknown. This study investigated the relationship of long-term coffee consumption between the age of 27 and 36 years with the prevalence of the MS at the age of 36 years. SUBJECT/METHODS: Data on coffee consumption and the MS components were derived from a healthy sample of 174 men and 194 women followed up from the age of 27 years onwards. Data analysis was performed with the use of generalized estimating equations and regression analysis. RESULTS: At the age of 36 years, the prevalence of the MS was 10.1%. The growth of coffee consumption did not differ significantly between subjects with or without the MS or its components. Regression analyses showed that one cup day(-1) higher coffee consumption was related to 0.11 mm Hg lower mean arterial blood pressure (P=0.03), 0.02 mg 100 ml(-1) higher triglyceride level (P=0.57), 0.04 mg 100 ml(-1) higher high-density lipoprotein cholesterol level (P=0.35), 0.09% higher HbA(1c) (P=0.12) and 0.02 cm larger waist circumference (P=0.57). After adjustment for physical activity, energy intake, smoking behaviour and alcohol consumption, none of the relationships between coffee consumption and the MS or its components was significant. CONCLUSIONS: Coffee consumption is not associated with the MS or its components in a healthy sample followed up for 9 years.


Subject(s)
Coffee , Metabolic Syndrome/epidemiology , Adult , Blood Pressure/drug effects , Cholesterol, HDL/blood , Coffee/adverse effects , Female , Glycated Hemoglobin/metabolism , Humans , Longitudinal Studies , Male , Metabolic Syndrome/chemically induced , Prevalence , Regression Analysis , Triglycerides/blood , Waist Circumference/drug effects
9.
Nature ; 446(7139): 1082-5, 2007 Apr 26.
Article in English | MEDLINE | ID: mdl-17460673

ABSTRACT

Gliding birds continually change the shape and size of their wings, presumably to exploit the profound effect of wing morphology on aerodynamic performance. That birds should adjust wing sweep to suit glide speed has been predicted qualitatively by analytical glide models, which extrapolated the wing's performance envelope from aerodynamic theory. Here we describe the aerodynamic and structural performance of actual swift wings, as measured in a wind tunnel, and on this basis build a semi-empirical glide model. By measuring inside and outside swifts' behavioural envelope, we show that choosing the most suitable sweep can halve sink speed or triple turning rate. Extended wings are superior for slow glides and turns; swept wings are superior for fast glides and turns. This superiority is due to better aerodynamic performance-with the exception of fast turns. Swept wings are less effective at generating lift while turning at high speeds, but can bear the extreme loads. Finally, our glide model predicts that cost-effective gliding occurs at speeds of 8-10 m s(-1), whereas agility-related figures of merit peak at 15-25 m s(-1). In fact, swifts spend the night ('roost') in flight at 8-10 m s(-1) (ref. 11), thus our model can explain this choice for a resting behaviour. Morphing not only adjusts birds' wing performance to the task at hand, but could also control the flight of future aircraft.


Subject(s)
Flight, Animal/physiology , Songbirds/physiology , Wings, Animal/anatomy & histology , Wings, Animal/physiology , Animals , Biomechanical Phenomena , Models, Biological , Netherlands , Songbirds/anatomy & histology
10.
J Agric Food Chem ; 48(7): 2986-90, 2000 Jul.
Article in English | MEDLINE | ID: mdl-10898653

ABSTRACT

Under controlled-environment conditions, ethametsulfuron-methyl doses that inhibited growth by 50% (ED(50)) were >100 and <1 g of active ingredient (ai) ha(-)(1) for ethametsulfuron-methyl-resistant (R) and -susceptible (S) wild mustard, respectively. There were no differences between the two biotypes with regard to absorption and translocation of the herbicide. Three days after treatment, approximately 90, 5, and 2% of the applied [(14)C]ethametsulfuron-methyl was found in the treated leaf, foliage, and roots of each biotype, respectively. Acetolactate synthase extracted from the two biotypes was equally sensitive to both ethametsulfuron-methyl and chlorsulfuron. These results indicate that resistance was not due to differences in the target site, absorption, or translocation. However, ethametsulfuron-methyl was metabolized more rapidly in the R than the S biotype. Approximately 82, 73, 42, 30, and 17% of the recovered radioactivity remained as ethametsulfuron-methyl in R wild mustard 3, 6, 18, 48, and 72 h after treatment, respectively. Conversely, 84, 79, 85, and 73% of the (14)C was ethametsulfuron-methyl in the S biotype 12, 24, 48, and 72 h after treatment, respectively. On the basis of these results, it is proposed that resistance is due to enhanced metabolism of ethametsulfuron-methyl in the R biotype.


Subject(s)
Benzoates/pharmacology , Herbicides/pharmacology , Mustard Plant/metabolism , Plants, Medicinal , Triazines/pharmacology , Absorption , Chromatography, High Pressure Liquid , Drug Resistance , Mustard Plant/drug effects
11.
Can J Microbiol ; 45(10): 840-8, 1999 Oct.
Article in English | MEDLINE | ID: mdl-10907421

ABSTRACT

Sphingomonas strain UG30 mineralizes both p-nitrophenol (PNP) and pentachlorophenol (PCP). Our current studies showed that UG30 oxidatively metabolized certain other p-substituted nitrophenols, i.e., p-nitrocatechol, 2,4-dinitrophenol (2,4-DNP), and 4,6-dinitrocresol with liberation of nitrite. 2,6-DNP, o- or m-nitrophenol, picric acid, or the herbicide dinoseb were not metabolized. Studies using 14C-labelled 2,4-DNP indicated that in glucose-glutamate broth cultures of UG30, greater than 90% of 103 microM 2,4-DNP was transformed to other compounds, while 8-19% of the 2,4-DNP was mineralized within 5 days. A significant portion (20-50%) of the 2,4-DNP was metabolized to highly polar metabolite(s) with one major unidentified metabolite accumulating from 5 to 25% of the initial radioactivity. The amounts of 2,4-DNP mineralized and converted to polar metabolites was affected by glutamate concentration in the medium. Nitrophenolic compounds metabolized by UG30 were also suitable substrates for the UG30 PCP-4-monooxygenase (pcpB gene expressed in Escherichia coli) which is likely central to degradation of these compounds. The wide substrate range of UG30 could render this strain useful in bioremediation of some chemically contaminated soils.


Subject(s)
2,4-Dinitrophenol/metabolism , Sphingomonas/metabolism , Biodegradation, Environmental , Escherichia coli/genetics , Gas Chromatography-Mass Spectrometry , Genes, Bacterial , Glucose/pharmacology , Glutamic Acid/pharmacology , Mixed Function Oxygenases/genetics , Mixed Function Oxygenases/metabolism , Nitrophenols/metabolism , Recombinant Proteins/genetics , Recombinant Proteins/metabolism , Sphingomonas/enzymology , Sphingomonas/genetics , Substrate Specificity
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