516 research outputs found
The use of an aircraft test stand for VTOL handling qualities studies
The VTOL flight tests stand for testing control concepts on the X-14B VSS aircraft in hover, is described. This stand permits realistic and safe piloted evaluation and checkout of various control systems and of parameter variations within each system to determine acceptability to the pilot. Pilots can use it as a practical training tool to practice procedures and flying techniques and become familiar with the aircraft characteristics. Some examples of test experience are given. The test stand allows the X14B to maneuver in hover from centered position + or - 9.7 deg in roll and + or - 9.3 deg in pitch, about + or - 6 deg in yaw, and + or - 15 cm in vertical translation. The unique vertical free flight freedom enables study of liftoffs and landings with power conditions duplicated. The response on the stand agrees well with that measured in free hovering flight, and pilot comments confirm this
Greenwashing No More: The Case for Stronger Regulation of Environmental Marketing
Fraudulent and deceptive environmental claims in marketing (sometimes called âgreenwashingâ) are a persistent problem in the United States, despite nearly thirty years of efforts by the Federal Trade Commission (FTC) to prevent it. This Essay focuses on a recent trend in greenwashing - fraudulent âorganicâ claims for nonagricultural products, such as home goods and personal care products. We offer three recommendations. First, we suggest ways that the FTC can strengthen its oversight of âorganicâ claims for nonagricultural products and improve coordination with the USDA. Second, we argue for inclusion of guidelines for âorganicâ claims in the next revision of the FTCâs Guidelines for the Use of Environmental Marketing Claims (often referred to as the âGreen Guidesâ), which the FTC is scheduled to revise in 2022. Finally, we assert that the FTC should formalize the Green Guides as binding regulations, rather than their current form as nonbinding interpretive guidance, as the USDA has done for the National Organic Program (NOP) regulations. This Essay concludes that more robust regulatory oversight of âorganicâ claims, together with efforts by the FTC to prevent other forms of greenwashing, will ultimately bolster demand for sustainable products and incentivize manufacturers to innovate to meet this demand
Inability of immunohistochemistry to predict clinical outcomes of endometrial cancer patients
Gossett DR, Alo P, Bristow RE, Galati M, Kyshtoobayeva A, Fruehauf J, Montz FJ. Inability of immunohistochemistry to predict clinical outcomes of endometrial cancer patients. Introduction: Despite optimal surgery, some patients with early endometrial carcinoma develop recurrence and die of disease. A number of immunohistochemical (IHC)-identified cell products (markers) have been proposed as predictors of recurrence. This study characterizes a large series of endometrial carcinomas with previously described markers as well as markers that have not been investigated in endometrial carcinoma. Patients and methods: Women who had undergone surgery for endometrial carcinoma were identified and specimens accessed. Tissue blocks were evaluated for ten IHC markers. Results were correlated with last known clinical status. Results: Mean follow-up was 43 months; complete data were available on 117 patients. Two women died of other causes; of the remaining 115, eight died of disease and six were alive with recurrence at last follow-up (12%). Vascular endothelial growth factor staining independently predicted recurrence and death. However, in multivariate analyses, only FIGO stage predicted outcome. Discussion: Our goal was to identify markers to predict which women with endometrial carcinoma were likely to have disease recurrence. We evaluated cell-cycle regulatory proteins, growth factors, hormone receptors, and angiogenic factors, but did not identify any marker that independently predicted outcome in multivariate analysis. This may reflect the few negative outcomes in our population.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/72601/1/j.1048-891x.2004.014028.x.pd
AFLOW-SYM: platform for the complete, automatic and self-consistent symmetry analysis of crystals
Determination of the symmetry profile of structures is a persistent challenge in materials science. Results often vary amongst standard packages, hindering autonomous materials development by requiring continuous user attention and educated guesses. This article presents a robust procedure for evaluating the complete suite of symmetry properties, featuring various representations for the point, factor and space groups, site symmetries and Wyckoff positions. The protocol determines a system-specific mapping tolerance that yields symmetry operations entirely commensurate with fundamental crystallographic principles. The self-consistent tolerance characterizes the effective spatial resolution of the reported atomic positions. The approach is compared with the most used programs and is successfully validated against the space-group information provided for over 54â
000 entries in the Inorganic Crystal Structure Database (ICSD). Subsequently, a complete symmetry analysis is applied to all 1.7+ million entries of the AFLOW data repository. The AFLOW-SYM package has been implemented in, and made available for, public use through the automated ab initio framework AFLOW
Fungal infections and antifungal prophylaxis in pediatric cardiac extracorporeal life support
ObjectiveInfections acquired by children during extracorporeal membrane oxygenation (ECMO) increase mortality. Our aim was to evaluate the effectiveness of prophylactic fluconazole on the incidence of fungal infections and to assess whether hospital-acquired fungal infection is associated with increased in-hospital mortality in pediatric cardiac patients requiring ECMO.MethodsWe retrospectively reviewed a prospectively maintained database and collected data on all hospital-acquired infections in patients supported for cardiac indications at a tertiary childrenâs hospital from 1989 to 2008.ResultsECMO was deployed 801 times in 767 patients. After exclusion criteria were applied, 261 pediatric patients supported for cardiac indications were studied. Fungal infection (blood, urine, or surgical site) occurred in 12% (31/261) of patients, 9 (7%) of 127 patients receiving fluconazole prophylaxis versus 22 (16.4%) of 134 without antifungal prophylaxis (PÂ =Â .02). Using a multivariable logistic regression model, the absence of fluconazole prophylaxis was associated with an increased risk of fungal infection (odds ratio [OR]Â =Â 2.8; 95% confidence intervals [CI], 1.2, 6.7; PÂ =Â .016). In a multivariable logistic regression model for in-hospital mortality, the presence of fungal infection was associated with increased odds (ORÂ =Â 3.8; 95% CI, 1.5, 9.6; PÂ =Â .005) of in-hospital mortality among cardiac patients requiring ECMO, and the absence of antifungal prophylaxis showed a trend toward the same (ORÂ =Â 1.6; 95% CI, 0.96, 2.8; PÂ =Â .072).ConclusionsChildren with cardiac disease supported with ECMO who acquire fungal infections have increased mortality. Routine fluconazole prophylaxis is associated with lower rates of fungal infections in these patients
AFLOW-CHULL: Cloud-Oriented Platform for Autonomous Phase Stability Analysis
A priori prediction of phase stability of materials is a challenging practice, requiring knowledge of all energetically-competing structures at formation conditions. Large materials repositories - housing properties of both experimental and hypothetical compounds - offer a path to prediction through the construction of informatics-based, ab-initio phase diagrams. However, limited access to relevant data and software infrastructure has rendered thermodynamic characterizations largely peripheral, despite their continued success in dictating synthesizability. Herein, a new module is presented for autonomous thermodynamic stability analysis implemented within the open-source, ab-initio framework AFLOW. Powered by the AFLUX Search-API, AFLOW-CHULL leverages data of more than 1.8 million compounds currently characterized in the AFLOW.org repository and can be employed locally from any UNIX-like computer. The module integrates a range of functionality: the identification of stable phases and equivalent structures, phase coexistence, measures for robust stability, and determination of decomposition reactions. As a proof-of-concept, thorough thermodynamic characterizations have been performed for more than 1,300 binary and ternary systems, enabling the identification of several candidate phases for synthesis based on their relative stability criterion - including 18 promising C15b-type structures and two half-Heuslers. In addition to a full report included herein, an interactive, online web application has been developed showcasing the results of the analysis, and is located at aflow.org/aflow-chull
Droplet Lasers:A Review of Current Progress
© 2017 IOP Publishing Ltd. It is perhaps surprising that something as fragile as a microscopic droplet could possibly form a laser. In this article we will review some of the underpinning physics as to how this might be possible, and then examine the state of the art in the field. The technology to create and manipulate droplets will be examined, as will the different classes of droplet lasers. We discuss the rapidly developing fields of droplet biolasers, liquid crystal laser droplets and explore how droplet lasers could give rise to new bio and chemical sensing and analysis. The challenges that droplet lasers face in becoming robust devices, either as sensors or as photonic components in the lab on chip devices, is assessed
Noninvasive options for âwearing-offâ in Parkinson's disease: a clinical consensus from a panel of UK Parkinson's disease specialists
In the past 4Â years, two adjunctive treatment options to levodopa have been licensed for use in the UK in patients with Parkinson's disease (PD) and motor fluctuations: opicapone, a third-generation catechol-O-methyl transferase inhibitor, and safinamide, a monoamine oxidase B inhibitor. This clinical consensus outlines the practical considerations relating to motor fluctuations and managing wearing-off in patients with PD, and provides a clinical insight to adjunctive treatment options, including opicapone and safinamide. Practice-based opinion was provided from a multidisciplinary steering Group of eight UK-based movement disorder and PD specialists, including neurologists, geriatricians and a nurse specialist, from England, Scotland and Wales
Scaling Properties of the Giant Dipole Resonance Width in Hot Rotating nuclei
We study the systematics of the giant dipole resonance width in hot
rotating nuclei as a function of temperature , spin and mass . We
compare available experimental results with theoretical calculations that
include thermal shape fluctuations in nuclei ranging from A=45 to A=208. Using
the appropriate scaled variables, we find a simple phenomenological function
which approximates the global behavior of the giant dipole
resonance width in the liquid drop model. We reanalyze recent experimental and
theoretical results for the resonance width in Sn isotopes and Pb.Comment: LaTeX, 4 pages with 4 figures (to appear in Phys. Rev. Lett.
Radial Flow in Au+Au Collisions at E=0.25-1.15 A GeV
A systematic study of energy spectra for light particles emitted at
midrapidity from Au+Au collisions at E=0.25-1.15 A GeV reveals a significant
non-thermal component consistent with a collective radial flow. This component
is evaluated as a function of bombarding energy and event centrality.
Comparisons to Quantum Molecular Dynamics (QMD) and Boltzmann-Uehling-Uhlenbeck
(BUU) models are made for different equations of state.Comment: 10 pages of text and 4 figures (all ps files in a uuencoded package)
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