2,842 research outputs found
Electrical cabling withstands severe environmental conditions
Multiconductor electrical cables retain their circuit integrity and remain flexible and abrasion resistant in severe environmental conditions of heat, vibration, and water
Modulation of GILT and PAX3 by Ganoderic Acid DM Enhances Radiation and Chemoimmunotherapy of Melanoma
Melanoma is an aggressive skin cancer that plagues Western populations. Current treatments such as surgery, chemotherapy, and high-dose radiation have had some success, but often fail in treating late stage metastatic melanoma. Immunotherapies have been successful in treating a small percentage of late stage patients, but these treatments do not provide a long-lasting response to effectively clear the tumor. Therefore, current studies have been investigating whether combining common treatments with immunotherapies would provide the necessary boost to further improve tumor killing. An optimum presentation of HLA class II proteins is essential for the activation of CD4+ T cells, which provide a sustained killing of malignant tumors by activating cytotoxic CD8+ T cells. Our laboratory has recently shown that the induction of Gamma-Interferon-inducible Lysosomal Thiol reductase (GILT) in melanoma favors HLA class II antigen processing and CD4+ T cells recognition of tumors. The present study examined the role of GILT in generating a greater pool of reduced and functional epitopes for HLA class II-mediated presentation and recognition of CD4+ T cells. This study also investigated the mechanisms by which GILT expression negatively regulates a tumorigenic molecule, paired box 3 (PAX3), in melanoma cells; and how regulation of PAX3 leads to melanoma cell sensitization to radiation and chemoimmunotherapy. Additionally, this study tested a chemotherapeutic agent (GA-DM), which induced apoptosis in a p53-dependent pathway and altered GILT, PAX3, and HLA class II molecules in melanoma cells in vitro. Interestingly, the combination of radiation and GA-DM treatment in vivo in the B16 melanoma mouse model displayed increased survival and decreased tumor volume among treatment groups. Based upon the results of this study, the combination treatment of radiation and GA-DM could be utilized to eliminate melanoma cells while boosting immune responses in the host. Understanding the molecular mechanisms of GILT-mediated downregulation of PAX3 as well as the radiation and GA-DM treatment death pathway could lead to a new target for devising novel chemoimmunotherapeutics for late stage metastatic melanoma
Laser anemometer measurements in a transonic axial-flow fan rotor
Laser anemometer surveys were made of the 3-D flow field in NASA rotor 67, a low aspect ratio transonic axial-flow fan rotor. The test rotor has a tip relative Mach number of 1.38. The flowfield was surveyed at design speed at near peak efficiency and near stall operating conditions. Data is presented in the form of relative Mach number and relative flow angle distributions on surfaces of revolution at nine spanwise locations evenly spaced from hub to tip. At each spanwise location, data was acquired upstream, within, and downstream of the rotor. Aerodynamic performance measurements and detailed rotor blade and annulus geometry are also presented so that the experimental results can be used as a test case for 3-D turbomachinery flow analysis codes
Compact Gas Turbine Sub-Project - TC 4.2 Compact, High Overall Pressure Ratio (OPR 50+) Gas Generator
This is an overview of the technical challenges, objectives, and approaches to enable compact, high overall pressure
ratio gas turbine engine in support of NASA N+3 goals
Unsteady Flows in a Single-Stage Transonic Axial-Flow Fan Stator Row
Measurements of the unsteady velocity field within the stator row of a transonic axial-flow fan were acquired using a laser anemometer. Measurements were obtained on axisymmetric surfaces located at 10 and 50 percent span from the shroud, with the fan operating at maximum efficiency at design speed. The ensemble-average and variance of the measured velocities are used to identify rotor-wake-generated (deterministic) unsteadiness and turbulence, respectively. Correlations of both deterministic and turbulent velocity fluctuations provide information on the characteristics of unsteady interactions within the stator row. These correlations are derived from the Navier-Stokes equation in a manner similar to deriving the Reynolds stress terms, whereby various averaging operators are used to average the aperiodic, deterministic, and turbulent velocity fluctuations which are known to be present in multistage turbomachines. The correlations of deterministic and turbulent velocity fluctuations throughout the axial fan stator row are presented. In particular, amplification and attenuation of both types of unsteadiness are shown to occur within the stator blade passage
A Standard Law for the Equatorward Drift of the Sunspot Zones
The latitudinal location of the sunspot zones in each hemisphere is
determined by calculating the centroid position of sunspot areas for each solar
rotation from May 1874 to June 2011. When these centroid positions are plotted
and analyzed as functions of time from each sunspot cycle maximum there appears
to be systematic differences in the positions and equatorward drift rates as a
function of sunspot cycle amplitude. If, instead, these centroid positions are
plotted and analyzed as functions of time from each sunspot cycle minimum then
most of the differences in the positions and equatorward drift rates disappear.
The differences that remain disappear entirely if curve fitting is used to
determine the starting times (which vary by as much as 8 months from the times
of minima). The sunspot zone latitudes and equatorward drift measured relative
to this starting time follow a standard path for all cycles with no dependence
upon cycle strength or hemispheric dominance. Although Cycle 23 was peculiar in
its length and the strength of the polar fields it produced, it too shows no
significant variation from this standard. This standard law, and the lack of
variation with sunspot cycle characteristics, is consistent with Dynamo Wave
mechanisms but not consistent with current Flux Transport Dynamo models for the
equatorward drift of the sunspot zones.Comment: 12 pages, 7 color figure
The Waldmeier Effect in Sunspot Cycles
We discuss two aspects of the Waldmeier Effect, namely (1) the rise times of
sunspot cycles are anti-correlated to their strengths (WE1) and (2) the rates
of rise of the cycles are correlated to their strengths (WE2). From analysis of
four different data sets we conclude that both WE1 and WE2 exist in all the
data sets. We study these effects theoretically by introducing suitable
stochastic fluctuations in our regular solar dynamo model.Comment: Magnetic Coupling between the Interior and Atmosphere of the Sun;
Astrophysics and Space Science Proceeding
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