58 research outputs found
Configuration design studies and wind tunnel tests of an energy efficient transport with a high-aspect-ratio supercritical wing
The results of design studies and wind tunnel tests of high aspect ratio supercritical wings suitable for a medium range, narrow body transport aircraft flying near M=0.80 were presented. The basic characteristics of the wing design were derived from system studies of advanced transport aircraft where detailed structural and aerodynamic tradeoffs were used to determine the most optimum design from the standpoint of fuel usage and direct operating cost. These basic characteristics included wing area, aspect ratio, average thickness, and sweep. The detailed wing design was accomplished through application of previous test results and advanced computational transonic flow procedures. In addition to the basic wing/body development, considerable attention was directed to nacelle/plyon location effects, horizontal tail effects, and boundary layer transition effects. Results of these tests showed that the basic cruise performance objectives were met or exceeded
Fertility Preservation and Financial Hardship among Adolescent and Young Adult Women with Cancer
Background: Financial hardship among adolescents and young adults (AYA) with cancer who receive gonadotoxic treatments may be exacerbated by the use of fertility services. This study examined whether AYA women with cancer who used fertility preservation had increased financial hardship. Methods: AYA women with cancer in North Carolina and California completed a survey in 2018–2019. Cancer-related financial hardship was compared between women who cryopreserved oocytes or embryos for fertility preservation after cancer diagnosis (n ¼ 65) and women who received gonadotoxic treatment and reported discussing fertility with their provider, but did not use fertility preservation (n ¼ 491). Multivariable log-binomial regression was used to estimate prevalence ratios and 95% confidence intervals (CI). Results: Women were a median age of 33 years at diagnosis and 7 years from diagnosis at the time of survey. Women who used fertility preservation were primarily ages 25 to 34 years at diagnosis (65%), non-Hispanic White (72%), and had at least a Bachelor’s degree (85%). In adjusted analysis, use of fertility preservation was associated with 1.50 times the prevalence of material financial hardship (95% CI: 1.08–2.09). The magnitude of hardship was also substantially higher among women who used fertility preservation: 12% reported debt of ≥$25,000 versus 5% in the referent group. Conclusions: This study provides new evidence that cryopreserving oocytes or embryos after cancer diagnosis for future family building is associated with increased financial vulnerability. Impact: More legislation that mandates insurance coverage to mitigate hardships stemming from iatrogenic infertility could improve access to fertility preservation for young women with cancer
Enhanced monitoring of life in the sea is a critical component of conservation management and sustainable economic growth
Marine biodiversity is a fundamental characteristic of our planet that depends on and influences climate, water quality, and many ocean state variables. It is also at the core of ecosystem services that can make or break economic development in any region. Our purpose is to highlight the need for marine biological observations to inform science and conservation management and to support the blue economy. We provide ten recommendations, applicable now, to measure and forecast biological Essential Ocean Variables (EOVs) as part of economic monitoring efforts. The UN Decade of Ocean Science for Sustainable Development (2021–2030) provides a timely opportunity to implement these recommendations to benefit humanity and enable the USD 3 trillion global ocean economy expected by 2030
Perspectives on Disconnects Between Scientific Information and Management Decisions on Post-fire Recovery in Western US
Environmental regulations frequently mandate the use of "best available" science, but ensuring that it is used in decisions around the use and protection of natural resources is often challenging. In the Western US, this relationship between science and management is at the forefront of post-fire land management decisions. Recent fires, post-fire threats (e.g. flooding, erosion), and the role of fire in ecosystem health combine to make post-fire management highly visible and often controversial. This paper uses post-fire management to present a framework for understanding why disconnects between science and management decisions may occur. We argue that attributes of agencies, such as their political or financial incentives, can limit how effectively science is incorporated into decision-making. At the other end of the spectrum, the lack of synthesis or limited data in science can result in disconnects between science-based analysis of post-fire effects and agency policy and decisions. Disconnects also occur because of the interaction between the attributes of agencies and the attributes of science, such as their different spatial and temporal scales of interest. After offering examples of these disconnects in post-fire treatment, the paper concludes with recommendations to reduce disconnects by improving monitoring, increasing synthesis of scientific findings, and directing social-science research toward identifying and deepening understanding of these disconnects
Installed Transonic 2D Nozzle Nacelle Boattail Drag Study
The Transonic Nozzle Boattail Drag Study was initiated in 1995 to develop an understanding of how external nozzle transonic aerodynamics effect airplane performance and how strongly those effects are dependent on nozzle configuration (2D vs. axisymmetric). MDC analyzed the axisymmetric nozzle. Boeing subcontracted Northrop-Grumman to analyze the 2D nozzle. AU participants analyzed the AGARD nozzle as a check-out and validation case. Once the codes were checked out and the gridding resolution necessary for modeling the separated flow in this region determined, the analysis moved to the installed wing/body/nacelle/diverter cases. The boat tail drag validation case was the AGARD B.4 rectangular nozzle. This test case offered both test data and previous CFD analyses for comparison. Results were obtained for test cases B.4.1 (M=0.6) and B.4.2 (M=0.938) and compared very well with the experimental data. Once the validation was complete a CFD grid was constructed for the full Ref. H configuration (wing/body/nacelle/diverter) using a combination of patched and overlapped (Chimera) grids. This was done to ensure that the grid topologies and density would be adequate for the full model. The use of overlapped grids allowed the same grids from the full configuration model to be used for the wing/body alone cases, thus eliminating the risk of grid differences affecting the determination of the installation effects. Once the full configuration model was run and deemed to be suitable the nacelle/diverter grids were removed and the wing/body analysis performed. Reference H wing/body results were completed for M=0.9 (a=0.0, 2.0, 4.0, 6.0 and 8.0), M=1.1 (a=4.0 and 6.0) and M=2.4 (a=0.0, 2.0, 4.4, 6.0 and 8.0). Comparisons of the M=0.9 and M=2.4 cases were made with available wind tunnel data and overall comparisons were good. The axi-inlet/2D nozzle nacelle was analyzed isolated. The isolated nacelle data coupled with the wing/body result enabled the interference effects of the installed nacelles to be determined. Isolated nacelle mm were made at M=0.9 and M=1.1 for both the supersonic and transonic nozzle settings. AU of the isolated nacelle cases were run at alpha=0. Full configuration runs were to be made at Mach numbers of 0.9, 1.1, and 2.4 (the same as the wing/body and isolated nacelles). Both the isolated nacelles and installed nacelles were run with inlet conditions designed to give zero spillage. This was to be done in order to isolate the boattail effects as much as possible. Full configuration runs with the supersonic nozzles were completed for M=0.9 and 1.1 at a=4.0 and 6.0 (4 runs total) and with the transonic nozzles at M=0.9 and 1.1 at a=2.0, 4.0 and 6.0 (6 runs total). Drag breakdowns were completed for the M=0.9 and M= 1.1 showing favorable interference drag for both cases
Three-Dimensional High-Frequency Ultrasonography for Early Detection and Characterization of Embryo Implantation Site Development in the Mouse.
Ultrasonography is a powerful tool to non-invasively monitor in real time the development of the human fetus in utero. Although genetically engineered mice have served as valuable in vivo models to study both embryo implantation and pregnancy progression, such studies usually require sacrifice of parous mice for subsequent phenotypic analysis. To address this issue, we used three-dimensional (3-D) reconstruction in silico of high-frequency ultrasound (HFUS) imaging data for early detection and characterization of murine embryo implantation sites and their development in utero. With HFUS imaging followed by 3-D reconstruction, we were able to precisely quantify embryo implantation site number and embryonic developmental progression in pregnant C57BL6J/129S mice from as early as 5.5 days post coitus (d.p.c.) through to 9.5 d.p.c. using a VisualSonics Vevo 2100 (MS550S) transducer. In addition to measurements of implantation site number, location, volume and spacing, embryo viability via cardiac activity monitoring was also achieved. A total of 12 dams were imaged with HFUS with approximately 100 embryos examined per embryonic day. For the post-implantation period (5.5 to 8.5 d.p.c.), 3-D reconstruction of the gravid uterus in mesh or solid overlay format enabled visual representation in silico of implantation site location, number, spacing distances, and site volume within each uterine horn. Therefore, this short technical report describes the feasibility of using 3-D HFUS imaging for early detection and analysis of post-implantation events in the pregnant mouse with the ability to longitudinally monitor the development of these early pregnancy events in a non-invasive manner. As genetically engineered mice continue to be used to characterize female reproductive phenotypes, we believe this reliable and non-invasive method to detect, quantify, and characterize early implantation events will prove to be an invaluable investigative tool for the study of female infertility and subfertility phenotypes based on a defective uterus
Motor-related functional MRI abnormalities in individuals genetically at risk for Huntington's Disease.
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