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Experiments and computations are presented for a foil pitching about its leading edge near a planar, solid boundary. The foil is examined when it is constrained in space and when it is unconstrained or freely swimming in the cross-stream direction. It was found that the foil has stable equilibrium altitudes: the time-averaged lift is zero at certain altitudes and acts to return the foil to these equilibria. These stable equilibrium altitudes exist for both constrained and freely swimming foils and are independent of the initial conditions of the foil. In all cases, the equilibrium altitudes move farther from the ground when the Strouhal number is increased or the reduced frequency is decreased. Potential flow simulations predict the equilibrium altitudes to within 3 %–11 %, indicating that the equilibrium altitudes are primarily due to inviscid mechanisms. In fact, it is determined that stable equilibrium altitudes arise from an interplay among three time-averaged forces: a negative jet deflection circulatory force, a positive quasistatic circulatory force and a negative added mass force. At equilibrium, the foil exhibits a deflected wake and experiences a thrust enhancement of 4 %–17 % with no penalty in efficiency as compared to a pitching foil far from the ground. These newfound lateral stability characteristics suggest that unsteady ground effect may play a role in the control strategies of near-boundary fish and fish-inspired robots.
To investigate whether adherence to the adapted Mediterranean Diet Score for Adolescents (MDS_A) and the adapted Mediterranean Diet Quality Index for Adolescents (KIDMED_A) is associated with better food/nutrient intakes and nutritional biomarkers.
The Healthy Lifestyle in Europe by Nutrition in Adolescence (HELENA) study is a cross-sectional study aiming to obtain comparable data on a variety of nutritional and health-related parameters in European adolescents aged 12·5–17·5 years.
Nine European countries.
European adolescents (n 2330) recruited to the HELENA study. Dietary intake was obtained with 24 h dietary recalls, an FFQ and a Food Choices and Preferences questionnaire. MDS_A was calculated as a categorical variable using cut-offs (MDS_A), as a continuous variable (zMDS_A) and with energy adjustments (zEnMDS_A). The KIDMED_A score was also calculated.
Multilevel linear regression analysis showed positive associations for zMDS_A and KIDMED_A with serum levels of vitamin D, vitamin C, plasma folate, holo-transcobalamin, β-carotene and n-3 fatty acids, while negative associations were observed with trans-fatty acid serum levels. For categorical indices, blood biomarkers showed few significant results. zMDS_A and KIDMED_A showed positive associations with vegetables and fruits intake, and negative associations with energy-dense and low-nutritious foods. zMDS_A and KIDMED_A were positively associated with all macronutrients, vitamins and minerals (all P < 0·0001), except with monosaccharides and PUFA for KIDMED_A and cholesterol for both indices (P < 0·05).
zMDS_A and KIDMED_A have shown the strongest associations with the dietary indicators and biomarkers that have been associated with the Mediterranean diet before, and are therefore considered the most appropriate and valid Mediterranean diet scores for European adolescents.
Trace elements are essential micronutrients for the human body. In this study, we evaluated the alterations in copper, chromium, manganese, selenium, magnesium, zinc, iron, arsenic, boron, and silicon levels in children with cyanotic and acyanotic CHD who underwent cardiac surgery with cardiopulmonary bypass. Participants were divided into the following three groups: patients acyanotic CHDs (n=34), patients with cyanotic CHDs (n=30), and healthy controls (n=30). Blood samples were collected before the surgery and 1 hour after the sternum was closed. Serum trace elements were determined by Inductively Coupled Plasma Optical Emission Spectrometer-ICAP 6000. The baseline serum arsenic, manganese, and zinc levels of both patient groups were lower compared with controls, but there was no significant difference between baseline serum trace element levels of cyanotic and acyanotic patients. In both the patient groups, there was a significant decrease in postoperative serum arsenic, boron, copper, and zinc levels, and a significant increase in postoperative serum iron and magnesium levels. Silicon levels increased in cyanotic patients. Alterations in trace element levels were in the same direction in cyanotic and acyanotic patients. Copper, zinc, and manganase replacement may be needed after on-pump cardiac surgery.
Adolescence represents an important period for the development of executive functions, which are a set of important cognitive processes including attentional control. However, very little is known regarding the associations of nutrition with components of executive functions in adolescence. Thus, the aim of this study was to investigate associations of dietary patterns and macronutrient composition with attention capacity in European adolescents. This cross-sectional study included 384 (165 boys and 219 girls) adolescents, aged 12·5–17·5 years, from five European countries in the Healthy Lifestyle in Europe by Nutrition in Adolescence study. Attention capacity was examined using the d2 Test of Attention. Dietary intake was assessed through two non-consecutive 24 h recalls using a computer-based self-administered tool. Three dietary patterns (diet quality index, ideal diet score and Mediterranean diet score) and macronutrient/fibre intakes were calculated. Linear regression analysis was conducted adjusting for age, sex, BMI, maternal education, family affluence scale, study centre and energy intake (only for Mediterranean diet score). In these adjusted regression analyses, higher diet quality index for adolescents and ideal diet score were associated with a higher attention capacity (standardised β=0·16, P=0·002 and β=0·15, P=0·005, respectively). Conversely, Mediterranean diet score or macronutrient/fibre intake were not associated with attention capacity (P>0·05). Our results suggest that healthier dietary patterns, as indicated by higher diet quality index and ideal diet score, were associated with attention capacity in adolescence. Intervention studies investigating a causal relationship between diet quality and attention are warranted.
Being one of Europe’s most densely populated countries, and having multiple nuclear installations, a heavy petrochemical industry, and terrorist targets, the Netherlands is at-risk for chemical, biological, or radionuclear (CBRN) incidents. Recent world and continental events show that this threat is real and that authorities may be underprepared.
The hypothesis of this study is that Dutch hospitals are underprepared to deal with these incidents.
A descriptive, cross-sectional study was performed. All 93 Dutch hospitals with an emergency department (ED) were sent a link to an online survey on different aspects of CBRN preparedness. Besides specific hospital information, information was obtained on the hospital’s disaster planning; risk perception; and availability of decontamination units, personal protective equipment (PPE), antidotes, radiation detection, infectiologists, isolation measures, and staff training.
Response rate was 67%. Sixty-two percent of participating hospitals were estimated to be at-risk for CBRN incidents. Only 40% had decontamination facilities and 32% had appropriate PPE available for triage and decontamination teams. Atropine was available in high doses in all hospitals, but specific antidotes that could be used for treating victims of CBRN incidents, such as hydroxycobolamine, thiosulphate, Prussian blue, Diethylenetriaminepentaacetic acid (DTPA), or pralidoxime, were less frequently available (74%, 65%, 18%, 14%, and 42%, respectively). Six percent of hospitals had radioactive detection equipment with an alarm function and 22.5% had a nuclear specialist available 24/7 in case of disasters. Infectiologists were continuously available in 60% of the hospitals. Collective isolation facilities were present in 15% of the hospitals.
There is a serious lack of hospital preparedness for CBRN incidents in The Netherlands.
MortelmansLJM, GaakeerMI, DieltiensG, AnseeuwK, SabbeMB. Are Dutch Hospitals Prepared for Chemical, Biological, or Radionuclear Incidents? A Survey Study. Prehosp Disaster Med. 2017;32(5):483–491.
We report a novel approach to the instantaneous photoinitiated synthesis of mixed anatase-rutile nanocrystalline TiO2 thin films with a three-dimensional nanostructure through pulsed white light irradiation of photosensitive Ti-organic precursor films. Pulsed photoinitiated pyrolysis accompanied by instantaneous self-assembly and crystallization occurred to form graphitic oxides-coated TiO2 nanograins. Subsequent pulsed light irradiation working as in situ pulsed photothermal treatment improved the crystalline quality of TiO2 film despite its low attenuation of light. The non-radiative recombination of photogenerated electrons and holes in TiO2 nanograins, coupled with inefficient heat dissipation due to low thermal conductivity, produces enough heat to provide the thermodynamic driving force for improving the crystalline quality. The graphitic oxides were reduced by pulsed photothermal treatment and can be completely removed by oxygen plasma cleaning. This photoinitiated nanofabrication technology opens a promising way for the low-cost and high-throughput manufacturing of nanostructured metal oxides as well as TiO2 nanocrystalline thin films.
The US Department of Energy (DOE) is partnering with fuel vendors to develop enhanced accident tolerant nuclear fuels for Generation III water cooled reactors. In comparison with the standard current uranium dioxide and zirconium alloy system UO2-Zr), the proposed alternative accident tolerant fuel (ATF) should better tolerate loss of cooling in the core for a considerably longer time while maintaining or improving the fuel performance during normal operation conditions. General Electric, Oak Ridge National Laboratory and their partners have proposed to replace zirconium based alloy cladding in current commercial power reactors with an iron-chromium-aluminum (FeCrAl) alloy cladding such as APMT. The use of FeCrAl alloys will greatly reduce the risk of operating the power reactors to produce electricity.
The integration of dissimilar materials is highly desirable for many different types of device applications but often challenging to achieve in practice. The unrivalled imaging capabilities of the aberration-corrected electron microscope enable enhanced insights to be gained into the atomic arrangements across heterostructured interfaces. This paper provides an overview of our recent observations of oxide-semiconductor heterostructures using aberration-corrected high-angle annular-dark-field and large-angle bright-field imaging modes. The perovskite oxides studied include strontium titanate, barium titanate, and strontium hafnate, which were grown on Si(001) and/or Ge(001) substrates using the techniques of molecular-beam epitaxy or atomic-layer deposition. The oxide layers displayed excellent crystallinity and sharp, abrupt interfaces were observed with no sign of any amorphous interfacial layers. The Ge(001) substrate surfaces invariably showed both 1× and 2× periodicity consistent with preservation of the 2 × 1 surface reconstruction following oxide growth. Overall, the results augur well for the future development of functional oxide-based devices integrated on semiconductor substrates.
Children, with their specific vulnerabilities and needs, make up to more than 20% of society, so they are at risk of getting involved in disasters. Are the specialists treating them for medical problems in daily life also capable to deal with them in disaster situations?
The goals of this study were to evaluate perceived knowledge and capability of tertiary pediatricians to deal with disasters, to identify promoting factors, and to evaluate education need and willingness to work.
A survey looking for demographics, hospital disaster planning, estimated risk and capability for disasters, training, and willingness to work, and a set of six content assessment questions to evaluate knowledge, were presented to emergency pediatricians and pediatric emergency physicians in specialized tertiary centers.
The response rate was 51%. Thirty-five percent had disaster training and 53% felt that disaster education should be obligatory in their curriculum. Risk for disasters was estimated from 2.4/10 for nuclear incidents to 7.6/10 for major trauma. Self-estimated capability for these situations ranged from 1.8/10 in nuclear incidents to 7.6/10 in major trauma. Unconditional willingness to work ranged from 37% in nuclear situations to 68% in pandemics. Mean score on the questions was 2.06/6. Training, knowledge of antidote and personal protective equipment (PPE) use, self-estimated capability, and exposure were significant predictors for higher scores. Willingness to work correlated significantly with age, self-estimated capability, and risk estimation. In case of chemical and nuclear incidents, there was correlation with knowledge on the use of decontamination, PPE, and radio-detection devices.
Despite a clear perception of the risks and a high willingness to work, preparedness is limited. The major conclusion is that basics of disaster management should be included in pediatric training.
MortelmansLJM, MaebeS, DieltiensG, AnseeuwK, SabbeMB, Van de VoordeP. Are Tertiary Care Paediatricians Prepared for Disaster Situations?Prehosp Disaster Med. 2016;31(2):126–131.
Central line–associated bloodstream infection (BSI) rates are a key quality metric for comparing hospital quality and safety. Traditional BSI surveillance may be limited by interrater variability. We assessed whether a computer-automated method of central line–associated BSI detection can improve the validity of surveillance.
Retrospective cohort study.
Eight medical and surgical intensive care units (ICUs) in 4 academic medical centers.
Traditional surveillance (by hospital staff) and computer algorithm surveillance were each compared against a retrospective audit review using a random sample of blood culture episodes during the period 2004–2007 from which an organism was recovered. Episode-level agreement with audit review was measured with κ statistics, and differences were assessed using the test of equal κ coefficients. Linear regression was used to assess the relationship between surveillance performance (κ) and surveillance-reported BSI rates (BSIs per 1,000 central line–days).
We evaluated 664 blood culture episodes. Agreement with audit review was significantly lower for traditional surveillance (κ [95% confidence interval (CI)] = 0.44 [0.37–0.51]) than computer algorithm surveillance (κ [95% CI] [0.52–0.64]; P = .001). Agreement between traditional surveillance and audit review was heterogeneous across ICUs (P = .001); furthermore, traditional surveillance performed worse among ICUs reporting lower (better) BSI rates (P = .001). In contrast, computer algorithm performance was consistent across ICUs and across the range of computer-reported central line–associated BSI rates.
Compared with traditional surveillance of bloodstream infections, computer automated surveillance improves accuracy and reliability, making interfacility performance comparisons more valid.
Infect Control Hosp Epidemiol 2014;35(12):1483–1490
This paper proposes a novel and simple expression for effective radius of annular-ring microstrip antennas (ARMAs) obtained using a recently emerged optimization algorithm of artificial bee colony (ABC) in calculating the resonant frequency at dominant mode (TM11). A total of 80 ARMAs having different parameters related to antenna dimensions and dielectric constants was simulated in terms of the resonant frequency with the help of an electromagnetic simulation software called IE3D™ based on method of moment. The effective radius expression was constructed and the unknown coefficients belonging to the expression were then optimally determined with the use of ABC algorithm. The proposed expression was verified through comparisons with the methods of resonant frequency calculation reported elsewhere. Also, it was further validated on an ARMA fabricated in this study. The superiority of the presented approach over the other methods proposed in the literature is that it does not need any sophisticated computations while achieving the most accurate results in the resonant frequency calculation of ARMAs.
Although the cadmium chloride treatment is an essential process for high efficiency thin film cadmium telluride photovoltaic devices, the precise mechanisms involved that improve the cadmium telluride layer are not well understood. In this investigation we apply advanced micro-structural characterization techniques to study the effect of varying the time of the cadmium chloride annealing treatment on the micro-structure of cadmium telluride solar cells deposited by close spaced sublimation (CSS) and relate this to cell performance. A range of techniques has been used to observe the morphological changes to the micro-structure as well as the chemical and crystallographic changes as a function of treatment parameters. Electrical tests that link the device performance with the micro-structural properties of the cells have also been undertaken. Techniques used include Transmission Electron Microscopy (TEM) for sub-grain analysis and XPS for composition-depth profiling. The study provides a new insight in to the mechanisms involved in the initiation and the subsequent complete re-crystallization of the cadmium telluride layer.
In this study, we investigated the prevalence, severity, and organisational factors of risk for psychological injury in a national sample of Australian school teachers, using the Psychological Injury Risk Indicator. We predicted that teachers would report higher levels of risk for psychological injury if working in schools located in rural areas, with a low socioeconomic index, and low psychosocial safety climate. Teachers from across Australia (N = 960) completed an online survey that measured risk for psychological injury and relevant organisational factors. We found a high number of teachers (26%) whose responses showed high risk, indicating the need for professional intervention in order to avoid potentially debilitating psychological injury. Analyses also showed main effects for two organisational factors, indicating that teachers most at risk for psychological injury tended to be employed by schools with low psychosocial safety climate and in areas with a low socioeconomic index. These results highlight the severe levels of work-related psychological injury risk in the Australian teacher population, and the important role for school administration and education departments in maintaining a working environment that supports staff psychologically.