2,027 research outputs found

    Trajectory Shaping Study for Various Ballistic Missile Scenarios

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    As the world continues to change and threatening countries begin to develop weapons capable of reaching all corners of the Earth, it becomes necessary forU.S.to find new ways of protecting the sovereignty it its people and borders of its nation. It is the purpose of this research to determine a more effective way of neutralizing ballistic missile warheads before they reenter Earth’s atmosphere and simulate a scenario showing this possibility in action. The ballistic missile code is written in MATLAB and initialized in the Entry Analysis Tool for Exploration Missions (EATEM). EATEM is a tool originally designed for the analysis of a Lander entering Martian atmosphere. It was designed by Shaun Deacon in the pursuit of his M.S. in Aerospace Engineering atEmbry-RiddleAeronauticalUniversity. The ballistic missile scenario is designed to show how a ballistic missile may be used to intercept an opposing ballistic missile. The intercept missile will launch a few minutes after the hostile launch has been detected and will initiate an intercept trajectory as it ascends through the atmosphere and into orbit

    The Development of a Performance Assessment Methodology for Activity Based Intelligence: A Study of Spatial, Temporal, and Multimodal Considerations

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    Activity Based Intelligence (ABI) is the derivation of information from a series of in- dividual actions, interactions, and transactions being recorded over a period of time. This usually occurs in Motion imagery and/or Full Motion Video. Due to the growth of unmanned aerial systems technology and the preponderance of mobile video devices, more interest has developed in analyzing people\u27s actions and interactions in these video streams. Currently only visually subjective quality metrics exist for determining the utility of these data in detecting specific activities. One common misconception is that ABI boils down to a simple resolution problem; more pixels and higher frame rates are better. Increasing resolution simply provides more data, not necessary more informa- tion. As part of this research, an experiment was designed and performed to address this assumption. Nine sensors consisting of four modalities were place on top of the Chester F. Carlson Center for Imaging Science in order to record a group of participants executing a scripted set of activities. The multimodal characteristics include data from the visible, long-wave infrared, multispectral, and polarimetric regimes. The activities the participants were scripted to cover a wide range of spatial and temporal interactions (i.e. walking, jogging, and a group sporting event). As with any large data acquisition, only a subset of this data was analyzed for this research. Specifically, a walking object exchange scenario and simulated RPG. In order to analyze this data, several steps of preparation occurred. The data were spatially and temporally registered; the individual modalities were fused; a tracking algorithm was implemented, and an activity detection algorithm was applied. To develop a performance assessment for these activities a series of spatial and temporal degradations were performed. Upon completion of this work, the ground truth ABI dataset will be released to the community for further analysis

    Using APOGEE Wide Binaries to Test Chemical Tagging with Dwarf Stars

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    Stars of a common origin are thought to have similar, if not nearly identical, chemistry. Chemical tagging seeks to exploit this fact to identify Milky Way subpopulations through their unique chemical fingerprints. In this work, we compare the chemical abundances of dwarf stars in wide binaries to test the abundance consistency of stars of a common origin. Our sample of 31 wide binaries is identified from a catalog produced by cross-matching APOGEE stars with UCAC5 astrometry, and we confirm the fidelity of this sample with precision parallaxes from Gaia DR2. For as many as 14 separate elements, we compare the abundances between components of our wide binaries, finding they have very similar chemistry (typically within 0.1 dex). This level of consistency is more similar than can be expected from stars with different origins (which show typical abundance differences of 0.3-0.4 dex within our sample). For the best measured elements, Fe, Si, K, Ca, Mn, and Ni, these differences are reduced to 0.05-0.08 dex when selecting pairs of dwarf stars with similar temperatures. Our results suggest that APOGEE dwarf stars may currently be used for chemical tagging at the level of ∼\sim0.1 dex or at the level of ∼\sim0.05 dex when restricting for the best-measured elements in stars of similar temperatures. Larger wide binary catalogs may provide calibration sets, in complement to open cluster samples, for on-going spectroscopic surveys.Comment: 21 pages, 14 figures, accepted for publication in Ap

    Rifts in Spreading Wax Layers

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    We report experimental results on the rift formation between two freezing wax plates. The plates were pulled apart with constant velocity, while floating on the melt, in a way akin to the tectonic plates of the earth's crust. At slow spreading rates, a rift, initially perpendicular to the spreading direction, was found to be stable, while above a critical spreading rate a "spiky" rift with fracture zones almost parallel to the spreading direction developed. At yet higher spreading rates a second transition from the spiky rift to a zig-zag pattern occurred. In this regime the rift can be characterized by a single angle which was found to be dependent on the spreading rate. We show that the oblique spreading angles agree with a simple geometrical model. The coarsening of the zig-zag pattern over time and the three-dimensional structure of the solidified crust are also discussed.Comment: 4 pages, Postscript fil

    Serum 25-Hydroxyvitamin D and Intact Parathyroid Hormone Influence Muscle Outcomes in Children and Adolescents

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    Increases in 25-hydroxyvitamin D concentrations are shown to improve strength in adults; however, data in pediatric populations are scant and equivocal. In this ancillary study of a larger-scale, multi-sited, double-blind, randomized, placebo-controlled vitamin D intervention in US children and adolescents, we examined the associations between changes in vitamin D metabolites and changes in muscle mass, strength, and composition after 12 weeks of vitamin D3 supplementation. Healthy male and female, black and white children and adolescents between the ages of 9 and 13 years from two US states (Georgia 34°N and Indiana 40°N) were enrolled in the study and randomly assigned to receive an oral vitamin D3 dose of 0, 400, 1000, 2000, or 4000 IU/d for 12 weeks between the winter months of 2009 to 2011 (N = 324). Analyses of covariance, partial correlations, and regression analyses of baseline and 12-week changes (post-baseline) in vitamin D metabolites (serum 25(OH)D, 1,25(OH)2 D, intact parathyroid hormone [iPTH]), and outcomes of muscle mass, strength, and composition (total body fat-free soft tissue [FFST], handgrip strength, forearm and calf muscle cross-sectional area [MCSA], muscle density, and intermuscular adipose tissue [IMAT]) were assessed. Serum 25(OH)D and 1,25(OH)2 D, but not iPTH, increased over time, as did fat mass, FFST, forearm and calf MCSA, forearm IMAT, and handgrip strength (p < 0.05). Vitamin D metabolites were not associated with muscle strength at baseline nor after the 12-week intervention. Changes in serum 25(OH)D correlated with decreases in forearm IMAT, whereas changes in serum iPTH predicted increases in forearm and calf MCSA and IMAT (p < 0.05). Overall, increases in 25(OH)D did not influence muscle mass or strength in vitamin D-sufficient children and adolescents; however, the role of iPTH on muscle composition in this population is unknown and warrants further investigation

    An 89Zr-HDL PET Tracer Monitors Response to a CSF1R Inhibitor

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    The immune function within the tumor microenvironment has become a prominent therapeutic target, with tumor-associated macrophages (TAMs) playing a critical role in immune suppression. We propose an 89Zr-labeled high-density lipoprotein (89Zr-HDL) nanotracer as a means of monitoring response to immunotherapy. Methods: Female MMTV-PyMT mice were treated with pexidartinib, a colony-stimulating factor 1 receptor (CSF1R) inhibitor, to reduce TAM density. The accumulation of 89Zr-HDL within the tumor was assessed using PET/CT imaging and autoradiography, whereas TAM burden was determined using immunofluorescence. Results: A significant reduction in 89Zr-HDL accumulation was observed in PET/CT images, with 2.9% ± 0.3% and 3.7% ± 0.2% injected dose/g for the pexidartinib- and vehicle-treated mice, respectively. This reduction was corroborated ex vivo and correlated with decreased TAM density. Conclusion: These results support the potential use of 89Zr-HDL nanoparticles as a PET tracer to quickly monitor the response to CSF1R inhibitors and other therapeutic strategies targeting TAMs.We thank the Small Animal Imaging Core, the Radiochemistry and Molecular Imaging Probes Core, and the Molecular Cytology Core at Memorial Sloan Kettering Cancer Center. This work was supported by National Institutes of Health grants R01 CA204441, P30 CA008748 and R01 CA220234. The authors thank the Tow Foundation and Memorial Sloan Kettering Cancer Center's Center for Molecular Imaging & Nanotechnology (CMINT), the Imaging and Radiation Sciences Program and the MSK Molecularly Targeted Intraoperative Imaging Fund.S

    Prognostic significance of serum inflammatory markers in esophageal cancer

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    Background The aim of this study was to assess the relative prognostic value of biomarkers to measure the systemic inflammatory response (SIR) and potentially improve prognostic modeling in patients undergoing potentially curative surgery for esophageal adenocarcinoma (EC). Methods Consecutive 330 patients undergoing surgery for EC between 2004 and 2018 within a regional UK cancer network were identified. Serum measurements of haemoglobin, C-reactive protein, albumin, modified Glasgow Prognostic Score (mGPS), and differential neutrophil to lymphocyte ratio (NLR) were obtained before surgery, and correlated with histopathological factors and outcomes. Primary outcome measures were disease-free (DFS) and overall survival (OS). Results Of 330 OC patients, 294 underwent potentially curative esophagectomy. Univariable DFS analysis revealed pT, pN, pTNM stage (all p < 0.001), poor differentiation (p = 0.001), vascular invasion (p < 0.001), R1 status (p < 0.001), perioperative chemotherapy (p = 0.009), CRP (p = 0.010), mGPS (p = 0.011), and NLR (p < 0.001), were all associated with poor survival. Multivariable Cox regression analysis of DFS revealed only NLR [Hazard Ratio (HR) 3.63, 95% Confidence Interval (CI) 2.11–6.24, p < 0.001] retained significance. Multivariable Cox regression analysis of OS revealed similar findings: NLR [HR 2.66, (95% CI 1.58–4.50), p < 0.001]. Conclusion NLR is an important SIR prognostic biomarker associated with DFS and OS in EC

    Proposed revision of the higher tier testing requirements for EPPO Standard PP1/170: Test methods for evaluating the side-effects of plant protection products on honeybees

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    contribution to session I  Regulatory issues Background: Regulatory evaluations for the effects of pesticides on honeybees in the EU are based on the honeybee test guidelines and risk assessment scheme of the European Plant Protection Organisation (EPPO). While this is considered to be robust and effective, it is also recognised that a continuous process of review and appropriate development is necessary. A working group of the International Commission for Plant-Bee Relationships (ICPBR) had been set up to review the current guidance set out in the EPPO PP1/170 standard for higher tier testing i.e. semi-field (cage) test and full field studies. The aim of this group was to utilise the considerable experience obtained with honey bee testing. This paper presents the working group’s proposed revision to the EPPO standard PP1/170, taking into account feedback received from the 10th ICPBR Symposium in Bucharest.Results: The primary aim of the group has been to produce guidance that is sufficiently detailed yet suitably flexible so that it enables tests to be conducted and evaluated without being too prescriptive. In particular, it recognises that higher tier testing may arise as a result of various initial concerns e.g. adult toxicity, brood effects and systemic toxicity. The guidance is designed to provide the different emphasis that is required to meet the specific requirements of individual studies. Conclusion: The revision of higher tier testing for honeybees presented in this paper is proposed as an update to the current EPPO PP1/170 standard.Keywords: honey bees, test guidelines, higher tier, semi-field (cage) tests, field tests
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