Towards Urban Air Mobility: NASAs Quadcopter Air Taxi Concept

Urban Air Mobility (UAM) is envisioned to be the future air transportation system over populated areas, where everything from small package delivery drones to passenger-carrying air taxis are able to interact safely and efficiently. The capacity of multi-rotor vehicles to perform vertical takeoff and landing (VTOL), together with their great maneuverability, make them an excellent choice for UAM aircraft. The accurate prediction of multirotor vehicles performance and acoustics is very challenging due to the unsteady and complex flows, as well as the aerodynamic interactions. By running high-fidelity computational fluid dynamics simulations on NASA supercomputers, researchers model the complex aerodynamics of multi-rotor flows, getting us closer to making UAM a reality

Computational Study of NASA's Quadrotor Urban Air Taxi Concept

High-fidelity computational fluid dynamics simulations have been carried out in order to analyze NASA's quadrotor urban air taxi concept for urban air mobility, also know as on-demand mobility applications. High-order accurate schemes, dual-time stepping, and the delayed detached-eddy simulation model have been employed. The ow solver has been loosely coupled with a rotorcraft comprehensive analysis code. The vehicle simulated is a six-passenger quadrotor for air taxi operations. A study of power reduction as a function of the rear-rotor to front-rotors vertical separation has been performed, for a quad-rotor without the airframe, in cruise flight conditions. Then, the quadrotor without the airframe has been simulated in hover. The airloads and wake geometries are analyzed. To finish the study the complete quadrotor vehicle is presented. NASA's quadrotor air taxi concept is one of the many concepts being developed by NASA in support of aircraft development for vertical take-o and landing air taxi operations

Effectiveness of an Informational Video-Assisted Presentation on Primary Care Provider Awareness, Knowledge, and Screening of Genitourinary Syndrome of Menopause: A Quality Improvement Project

Genitourinary Syndrome of Menopause (GSM) is a chronic and progressive condition that affects a significant number of menopausal women. This recently coined term encompasses a myriad of urogenital symptoms that are directly associated with the loss of estrogen. Women who are afflicted by GSM can experience genitourinary discomfort, pain, and incontinence and may be at higher risk for considerable clinical complications. As a result, GSM can impact a woman’s physical, emotional, social, and financial well-being. Additionally, GSM can lead to increased medical costs and elevated resource utilization and healthcare burden. Despite the far-reaching impact of this syndrome, however, it remains largely underdiagnosed and undertreated. The reasons for this treatment gap are multifactorial and include social stigma related to menopause, lack of awareness of relationship between hypoestrogenic state and symptoms, limited provider education on GSM and its management, and generally unwarranted safety concerns regarding treatment options. Genitourinary Syndrome of Menopause causes considerable and far-reaching harm and needs to be more effectively managed at all healthcare levels. To help reduce the GSM treatment gap among primary care providers in a large South Florida healthcare system, a quality improvement (QI) project was designed to enhance their awareness, knowledge, and screening of this condition. An evidence-based educational video presentation was created and utilized to inform clinicians about GSM’s impact and the different treatment modalities that are currently available for its stepwise, judicious management. Additionally, a screening tool was introduced during the presentation to help facilitate identification of GSM. Pretest and posttest surveys helped quantify the change in clinicians’ awareness, knowledge, and screening of GSM. The scores of these surveys were statistically analyzed and compared. The results pointed to a significant increase in knowledge and screening following the intervention. The small size of this study may limit its relevance, but points to the value of provider education in GSM management and, in turn, the enhancement of postmenopausal women’s health

Studies on the alveolar macrophage

This thesis is concerned with (1) the identification of membrane receptors on alveolar macrophages, particularly those for histamine, and (2) some of the metabolic changes which the cell undergoes following incubation with histamine, either in free solution or when bound to particles.In preliminary experiments, in which some of the variables associated with the "rosette technique" were examined, it was shown that alveolar macrophages bind IgG-coated erythrocytes (EAg) as well as sheep cells sensitized with IgM and whole serum as a source of complement (EAm"C3"). Therefore, lung macrophages, like most other leucocytes, appear to bear "immunological receptors" for IgG and complement (presumably C3).The "rosette technique" was then employed for the identification of histamine receptors on various guinea pig leucocytes using histamine coupled as a rabbit serum albumin conjugate (H-RSA) to formalised ox red cells. It was found that the number of "histamine rosettes" varied from 60-81% for alveolar macrophages, 14-73% for peritoneal macrophages, 14-30% for blood monocytes, 27-48% for lymph node cells, 7-24% for blood lymphocytes and 0-29% for peritoneal and blood neutrophils. Virtually no histamine rosettes were formed with eosinophils or basophils. The percentage of rosette-forming target cells was directly related to the concentration of erythrocyte-bound H-RSA. Free histamine partially inhibited rosette formation by alveolar macrophages in a dose-dependent fashion from 10⁻³ to 10⁻⁵ moles.1⁻¹ , and complete inhibition was achieved by the H-RSA conjugate. In contrast, amines closely related to histamine such as L-histidine and the major histamine catabolites, imidazoleacetic acid, 1,4-methylhistamine, l-methyl-4- imidazoleacetic acid and N-acetylhistamine, had no inhibitory effect.The histamine Hl-receptor antagonists, mepyramine and chlorpheniramine, and the Hl-receptor agonist, 2-(2-aminoethyl) thiazole, inhibited rosette formation by alveolar macrophages in a dose-dependent fashion. In contrast, the H2-receptor antagonists, burimamide and metiamide, and the H2-receptor agonists, Dimaprit and 4-methylhistamine, were inactive. These- experiments suggested that (1) compared to other leucocytes, histamine receptors are particularly well expressed on the alveolar macrophage, (2) these receptors have a high degree of specificity for histamine in that other amines, closely related chemically, did not inhibit rosette formation, and (3) the binding of histamine to the alveolar macrophage membrane is HI- and not H2-receptor dependent.Experiments were then undertaken to determine whether free histamine, or histamine bound to particles, interacted with its membrane receptor to initiate the "respiratory burst" in alveolar macrophages. Superoxide anion formation (0₂⁻) and chemiluminescence, recognized features of the "respiratory burst" of phagocytic cells, were generated by alveolar macrophages following incubation with H-RSA bound to zymosan (H-RSAZ) (and also H-RSA linked to a number of other inert particles such as Sephadex and polystyrene beads).The degree of 0₂⁻ generation and light emission was comparable to that achieved with serum treated zymosan (STZ). Superoxide formation by alveolar macrophages was related to the concentra¬ tion of histamine conjugate bound to the zymosan particles as well as the time of incubation. As with histamine rosettes, 0₂⁻ production generated by H-RSAZ in alveolar macrophages also appeared to be dependent on HI-, but not H2-, histamine receptors. Chemiluminescence induced by H-RSAZ was also time- and dose-dependent and totally inhibitible by superoxide dismutase indicating that the 0₂⁻ formation and the burst of light emission are closely related events in the alveolar macrophage. Histamine in free solution did not appear to promote 0₂⁻ generation or chemiluminescence in alveolar macrophages.Studies were then undertaken in an attempt to determine whether histamine influenced the release of the lysosomal enzyme, ß-glucuronidase, following incubation of alveolar macrophages with complement-coated zymosan. Histamine induced a small, but significant, increase in STZ-induced ß-glucuronidase release but had no apparent effect on the elaboration of the cytoplasmic enzyme, lactic dehydrogenase. Experiments to determine whether this was an HI- and/or H2- effect were inconclusive. H-RSAZ alone did not appear to influence ß-glucuronidase release.The general conclusion of this work is that there is a direct relationship between histamine and lung macrophages but that for the initiation of the "respiratory burst" histamine requires to be bound to particles to achieve appreciable biological effects. Since histamine is known to bind to a number of plasma proteins ("histaminopexy") these observations may be of significance both physio¬ logically, in the regulation of oxygen-dependent killing by lung macrophages, and also in disease states where high concentrations of histamine in bronchial secretions may adversely influence the normal functions of alveolar macrophages

Teaching Pride and Prejudice by Jane Austen through a Series of Lesson Plans in the 21st Century

This project encompasses a series of seventeen lesson plans covering a 3-week period of classroom teaching on Pride and Prejudice by Jane Austen. These lesson plans are designed to be taught in a span of fifty minutes. They were also created for an 11th grade College Preparatory(CP) class in which both native English speakers and multilingual students, who have a high World-Class Instructional Design and Assessment (WIDA) level can be found. These students are at a WIDA Level 5, which means they have advanced listening, writing, speaking, and reading skills. Although these multilingual students find themselves at the highest WIDA Level, they recently got out of the ESL program and might still need support navigating the challenges of a mainstream English classroom. The student population is as follows: 25 students in total—10 Hispanic students from Ecuador, El Salvador, and Puerto Rico, 3 Vietnamese students, and the rest are native English speakers

Inversion of multiconfiguration complex EMI data with minimum gradient support regularization: A case study

Frequency-domain electromagnetic instruments allow the collection of data in different configurations, that is, varying the intercoil spacing, the frequency, and the height above the ground. Their handy size makes these tools very practical for near-surface characterization in many fields of applications, for example, precision agriculture, pollution assessments, and shallow geological investigations. To this end, the inversion of either the real (in-phase) or the imaginary (quadrature) component of the signal has already been studied. Furthermore, in many situations, a regularization scheme retrieving smooth solutions is blindly applied, without taking into account the prior available knowledge. The present work discusses an algorithm for the inversion of the complex signal in its entirety, as well as a regularization method that promotes the sparsity of the reconstructed electrical conductivity distribution. This regularization strategy incorporates a minimum gradient support stabilizer into a truncated generalized singular value decomposition scheme. The results of the implementation of this sparsity-enhancing regularization at each step of a damped Gauss-Newton inversion algorithm (based on a nonlinear forward model) are compared with the solutions obtained via a standard smooth stabilizer. An approach for estimating the depth of investigation, that is, the maximum depth that can be investigated by a chosen instrument configuration in a particular experimental setting is also discussed. The effectiveness and limitations of the whole inversion algorithm are demonstrated on synthetic and real data sets

Low-mass eclipsing binaries in the WFCAM Transit Survey : The persistence of the M-dwarf radius inflation problem

This article has been accepted for publication in Monthly Notices of the Royal Astronomical Society. © 2018 The Author(s). Published by Oxford University Press on behalf of the Royal Astronomical Society. All rights reserved.We present the characterization of five new short-period low-mass eclipsing binaries (LMEBs) from the WFCAM Transit Survey. The analysis was performed by using the photometric WFCAM J-mag data and additional low- and intermediate-resolution spectroscopic data to obtain both orbital and physical properties of the studied sample. The light curves and the measured radial velocity curves were modelled simultaneously with the JKTEBOP code, with Markov chain MonteCarlo simulations for the error estimates. The best-model fit have revealed that the investigated detached binaries are in very close orbits, with orbital separations of 2.9 ≤ a ≤ 6.7R⊙ and short periods of 0.59 ≤ Porb ≤ 1.72 d, approximately. We have derived stellar masses between 0.24 and 0.72M⊙ and radii ranging from 0.42 to 0.67 R⊙. The great majority of the LMEBs in our sample has an estimated radius far from the predicted values according to evolutionary models. The components with derived masses of M < 0.6M⊙ present a radius inflation of ~9 per cent or more. This general behaviour follows the trend of inflation for partially radiative stars proposed previously. These systems add to the increasing sample of low-mass stellar radii that are not well-reproduced by stellarmodels. They further highlight the need to understand the magnetic activity and physical state of small stars. Missions like TESS will provide many such systems to perform high-precision radius measurements to tightly constrain low-mass stellar evolution models.Peer reviewe

High-Fidelity Computational Aerodynamics of Multi-Rotor Unmanned Aerial Vehicles

High-fidelity Computational Fluid Dynamics (CFD) simulations have been carried out for several multi-rotor Unmanned Aerial Vehicles (UAVs). Three vehicles have been studied: the classic quadcopter DJI Phantom 3, an unconventional quadcopter specialized for forward flight, the SUI Endurance, and an innovative concept for Urban Air Mobility (UAM), the Elytron 4S UAV. The three-dimensional unsteady Navier-Stokes equations are solved on overset grids using high-order accurate schemes, dual-time stepping, and a hybrid turbulence model. The DJI Phantom 3 is simulated with different rotors and with both a simplified airframe and the real airframe including landing gear and a camera. The effects of weather are studied for the DJI Phantom 3 quadcopter in hover. The SUI En- durance original design is compared in forward flight to a new configuration conceived by the authors, the hybrid configuration, which gives a large improvement in forward thrust. The Elytron 4S UAV is simulated in helicopter mode and in airplane mode. Understanding the complex flows in multi-rotor vehicles will help design quieter, safer, and more efficient future drones and UAM vehicles