94 research outputs found

    Experimental investigation of wing tip vortex

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    Particle image velocimetery was used in a low-speed wind tunnel to investigate and characterize wing tip vortex structures. A rectangular wing of a SWIM model was used as a vortex generator in two different configurations, (i) plain wing and (ii) flapped wing with trailing edge flap extended at 20 degrees. Vortex flow quantities and their dependence on angle of attack at a chord base Reynolds Number of 32.8x103 and 43.8x103 were evaluated. Assessment of measured data reveals that the peak values of tangential velocities, vortex strength and vorticities are directly proportional to the angle of attack. The vortex core radius value grows slowly as the angle of attack is increased. Both plain and flapped configurations showed similar trends. The peak tangential velocities and circulation distribution doubled when the flapped configuration was used instead of the plain wing

    Neurotropic Manifestations as a Potential Risk Factor for Schizophrenia Following in utero Exposure to SARS-CoV-2

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    Background: COVID-19 infection is associated with neurologic and psychiatric morbidity that suggests a direct effect of the virus or secondary effect of an inflammatory process. These neuropsychiatric consequences may increase the likelihood of schizophrenia in the offspring of women who become infected with COVID-19 during their pregnancy. Methods: We performed a directed narrative review of the literature focusing on the proposed pathophysiological processes that lead to schizophrenia and known pathological consequences of COVID-19 infection. Results: Schizophrenia in adult offspring has been associated with maternal infections during pregnancy by a wide range of respiratory and neurotropic pathogens. Spikes in the incidence of schizophrenia approximately 20 years after several influenza pandemics have been documented. There are multiple lines of evidence suggesting that a similar pattern may be seen due to the recent COVID-19 pandemic. These include the nonspecific consequences of acute illness and hyperpyrexia, as well as more specific derangements of brain development related to direct effects of the virus or secondary effects of the inflammatory response on the developing brain. There is the potential to prospectively test this hypothesis by following the offspring of women who are known to have developed COVID-19 during their pregnancy. Conclusion: The COVID-19 pandemic is likely associated with a range of future neuropsychiatric consequences in people whose mothers suffered the infection during their fetal development. It is important to try to follow these offspring to determine the full range of consequences of COVID-19 infection

    Experimental investigation of plain- and flapped-wing tip vortices

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    Particle image velocimetry was used in a low-speed wind tunnel to investigate and characterize wing tip vortex structures. A rectangular wing of a subsonic wall interference model was used as a vortex generator in two different configurations: 1) plain wing and 2) flapped wing with the trailing-edge flap extended at 20 degrees. Vortex flow quantities and their dependence on angle of attack at Reynolds numbers of 32:8 � 103 and 43:8 � 103 were evaluated. Assessment of measured data reveals that the peak values of tangential velocities, vortex strength, and vorticities are directly proportional to the angle of attack. The vortex core radius value grows slowly as the angle of attack is increased. Both plain and flapped configurations showed similar trends. The peak tangential velocities and circulation almost doubled when the flapped configuration was used instead of the plain wing

    Femtosecond Laser Induced Structural Dynamics and Melting of Cu (111) Single Crystal. An Ultrafast Time-Resolved X-Ray Diffraction Study

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    Femtosecond, 8.04 keV x-ray pulses are used to probe the lattice dynamics of a 150 nm Cu (111) single crystal on a mica substrate irradiated with 400 nm, 100 fs laser pulses. For pump fluences below the damage and melting thresholds, we observed lattice contraction due to the formation of a blast force and coherent acoustic phonons with a period of ∼69 ps. At larger pump fluence, solid to liquid phase transition, annealing, and recrystallization were measured in real time by monitoring the intensity evolution of the probing fs x-ray rocking curves, which agreed well with theoretical simulation results. The experimental data suggest that the melting process is a purely thermal phase transition. This study provides, in real time, an ultrafast time-resolved detailed description of the significant processes that occur as a result of the interaction of a femtosecond light-pulse with the Cu (111) crystal surface. Published by AIP Publishing. [http://dx.doi.org/10.1063/1.4975198

    Femtosecond Laser Induced Structural Dynamics and Melting of Cu (111) Single Crystal. An Ultrafast Time-Resolved X-Ray Diffraction Study

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    Femtosecond, 8.04 keV x-ray pulses are used to probe the lattice dynamics of a 150 nm Cu (111) single crystal on a mica substrate irradiated with 400 nm, 100 fs laser pulses. For pump fluences below the damage and melting thresholds, we observed lattice contraction due to the formation of a blast force and coherent acoustic phonons with a period of ∼69 ps. At larger pump fluence, solid to liquid phase transition, annealing, and recrystallization were measured in real time by monitoring the intensity evolution of the probing fs x-ray rocking curves, which agreed well with theoretical simulation results. The experimental data suggest that the melting process is a purely thermal phase transition. This study provides, in real time, an ultrafast time-resolved detailed description of the significant processes that occur as a result of the interaction of a femtosecond light-pulse with the Cu (111) crystal surface. Published by AIP Publishing. [http://dx.doi.org/10.1063/1.4975198

    Diagnostic evaluation of blunt abdominal trauma scoring system (BATSS)

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    Background: Blunt force abdominal trauma is a typical emergency room presentation in both adults and children. Trauma is widely acknowledged as one of the primary causes of illness and mortality in poor nations, as well as the greatest cause of death in those under the age of 45.Objectives: This study aims to study the diagnostic evaluation of blunt abdominal trauma scoring system (BATSS) in patients with blunt abdominal trauma in Zagazig University Hospital.Patients and methods: This study was conducted on 48 patients suffering from blunt abdominal trauma in Emergency Department of Zagazig University Hospital from January 2021 to June 2021.Result: The mean age of patients in the study was 25.87±10.7 years (range 17–61 years). Of the forty eight patients in the study there were 13 females (27.1%) and thirty five males (72.9%).There was statistically significant difference between blunt abdominal trauma scoring system (BATSS) and types of injury p<0.001. There was no statistically significant difference between blunt abdominal trauma scoring system (BATSS) and each of patients' sex and causes of injury p>0.05. Conclusion: The BATSS score system can be used as an initial screening to predict blunt abdominal trauma outcome and can be the basis of management in patients who experience blunt abdominal trauma

    Low Reynolds number effect on CFD prediction of bio inspired aerodynamics

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    This work is motivated by the need for the implementation of the best numerical modelsfor low Reynolds flows and presents the state–of–the–art of the implemented models for thetransition of the laminar-turbulent predictions. The numerical models are applied to investigatethe aerodynamic characteristics and flow behavior around bird–like airfoils. Two DimensionalReynolds Averaged Navier Stokes (2D RANS) and Three-Dimensional Unsteady (3D U-RANS)methods are applied at a Reynolds number of105, whereas two-dimensional laminar simulationsand three-dimensional Large Eddy Simulation are employed for the known Owl-like airfoil atReynolds number of2.3×104. The numerical results of flow fields around Owl-like airfoil atthe latter Reynolds number using two-dimensional laminar and 3DLES predict correctly theunsteadiness of the aerodynamic coefficients. The 2D and 3D RANS methods are predicting wellthe aerodynamics characteristics for the man-made-bird-like airfoil at Reynolds number of105

    Evaluation of a clinical decision support strategy to increase seasonal influenza vaccination among hospitalized children before inpatient discharge

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    Importance: Hospitalized children are at increased risk of influenza-related complications, yet influenza vaccine coverage remains low among this group. Evidence-based strategies about vaccination of vulnerable children during all health care visits are especially important during the COVID-19 pandemic. Objective: To design and evaluate a clinical decision support (CDS) strategy to increase the proportion of eligible hospitalized children who receive a seasonal influenza vaccine prior to inpatient discharge. Design, Setting, and Participants: This quality improvement study was conducted among children eligible for the seasonal influenza vaccine who were hospitalized in a tertiary pediatric health system providing care to more than half a million patients annually in 3 hospitals. The study used a sequential crossover design from control to intervention and compared hospitalizations in the intervention group (2019-2020 season with the use of an intervention order set) with concurrent controls (2019-2020 season without use of an intervention order set) and historical controls (2018-2019 season with use of an order set that underwent intervention during the 2019-2020 season). Interventions: A CDS intervention was developed through a user-centered design process, including (1) placing a default influenza vaccine order into admission order sets for eligible patients, (2) a script to offer the vaccine using a presumptive strategy, and (3) just-in-time education for clinicians addressing vaccine eligibility in the influenza order group with links to further reference material. The intervention was rolled out in a stepwise fashion during the 2019-2020 influenza season. Main Outcomes and Measures: Proportion of eligible hospitalizations in which 1 or more influenza vaccines were administered prior to discharge. Results: Among 17 740 hospitalizations (9295 boys [52%]), the mean (SD) age was 8.0 (6.0) years, and the patients were predominantly Black (n = 8943 [50%]) or White (n = 7559 [43%]) and mostly had public insurance (n = 11 274 [64%]). There were 10 997 hospitalizations eligible for the influenza vaccine in the 2019-2020 season. Of these, 5449 (50%) were in the intervention group, and 5548 (50%) were concurrent controls. There were 6743 eligible hospitalizations in 2018-2019 that served as historical controls. Vaccine administration rates were 31% (n = 1676) in the intervention group, 19% (n = 1051) in concurrent controls, and 14% (n = 912) in historical controls (P \u3c .001). In adjusted analyses, the odds of receiving the influenza vaccine were 3.25 (95% CI, 2.94-3.59) times higher in the intervention group and 1.28 (95% CI, 1.15-1.42) times higher in concurrent controls than in historical controls. Conclusions and Relevance: This quality improvement study suggests that user-centered CDS may be associated with significantly improved influenza vaccination rates among hospitalized children. Stepwise implementation of CDS interventions was a practical method that was used to increase quality improvement rigor through comparison with historical and concurrent controls

    Antimicrobial resistance among migrants in Europe: a systematic review and meta-analysis

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    BACKGROUND: Rates of antimicrobial resistance (AMR) are rising globally and there is concern that increased migration is contributing to the burden of antibiotic resistance in Europe. However, the effect of migration on the burden of AMR in Europe has not yet been comprehensively examined. Therefore, we did a systematic review and meta-analysis to identify and synthesise data for AMR carriage or infection in migrants to Europe to examine differences in patterns of AMR across migrant groups and in different settings. METHODS: For this systematic review and meta-analysis, we searched MEDLINE, Embase, PubMed, and Scopus with no language restrictions from Jan 1, 2000, to Jan 18, 2017, for primary data from observational studies reporting antibacterial resistance in common bacterial pathogens among migrants to 21 European Union-15 and European Economic Area countries. To be eligible for inclusion, studies had to report data on carriage or infection with laboratory-confirmed antibiotic-resistant organisms in migrant populations. We extracted data from eligible studies and assessed quality using piloted, standardised forms. We did not examine drug resistance in tuberculosis and excluded articles solely reporting on this parameter. We also excluded articles in which migrant status was determined by ethnicity, country of birth of participants' parents, or was not defined, and articles in which data were not disaggregated by migrant status. Outcomes were carriage of or infection with antibiotic-resistant organisms. We used random-effects models to calculate the pooled prevalence of each outcome. The study protocol is registered with PROSPERO, number CRD42016043681. FINDINGS: We identified 2274 articles, of which 23 observational studies reporting on antibiotic resistance in 2319 migrants were included. The pooled prevalence of any AMR carriage or AMR infection in migrants was 25·4% (95% CI 19·1-31·8; I2 =98%), including meticillin-resistant Staphylococcus aureus (7·8%, 4·8-10·7; I2 =92%) and antibiotic-resistant Gram-negative bacteria (27·2%, 17·6-36·8; I2 =94%). The pooled prevalence of any AMR carriage or infection was higher in refugees and asylum seekers (33·0%, 18·3-47·6; I2 =98%) than in other migrant groups (6·6%, 1·8-11·3; I2 =92%). The pooled prevalence of antibiotic-resistant organisms was slightly higher in high-migrant community settings (33·1%, 11·1-55·1; I2 =96%) than in migrants in hospitals (24·3%, 16·1-32·6; I2 =98%). We did not find evidence of high rates of transmission of AMR from migrant to host populations. INTERPRETATION: Migrants are exposed to conditions favouring the emergence of drug resistance during transit and in host countries in Europe. Increased antibiotic resistance among refugees and asylum seekers and in high-migrant community settings (such as refugee camps and detention facilities) highlights the need for improved living conditions, access to health care, and initiatives to facilitate detection of and appropriate high-quality treatment for antibiotic-resistant infections during transit and in host countries. Protocols for the prevention and control of infection and for antibiotic surveillance need to be integrated in all aspects of health care, which should be accessible for all migrant groups, and should target determinants of AMR before, during, and after migration. FUNDING: UK National Institute for Health Research Imperial Biomedical Research Centre, Imperial College Healthcare Charity, the Wellcome Trust, and UK National Institute for Health Research Health Protection Research Unit in Healthcare-associated Infections and Antimictobial Resistance at Imperial College London
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