2,695 research outputs found

    IMMACCS: A Multi-Agent Decision-Support System

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    This report describes work performed by the Collaborative Agent Design Research Center for the US Marine Corps Warfighting Laboratory (MCWL), on the IMMACCS experimental decision-support system. IMMACCS (Integrated Marine Multi-Agent Command and Control System) incorporates three fundamental concepts that distinguish it from existing (i.e., legacy) command and control applications. First, it is a collaborative system in which computer-based agents assist human operators by monitoring, analyzing, and reasoning about events in near real-time. Second, IMMACCS includes an ontological model of the battlespace that represents the behavioral characteristics and relationships among real world entities such as friendly and enemy assets, infrastructure objects (e.g., buildings, roads, and rivers), and abstract notions. This object model provides the essential common language that binds all IMMACCS components into an integrated and adaptive decision-support system. Third, IMMACCS provides no ready made solutions that may not be applicable to the problems that will occur in the real world. Instead, the agents represent a powerful set of tools that together with the human operators can adjust themselves to the problem situations that cannot be predicted in advance. In this respect, IMMACCS is an adaptive command and control system that supports planning, execution and training functions concurrently. The report describes the nature and functional requirements of military command and control, the architectural features of IMMACCS that are designed to support these operational requirements, the capabilities of the tools (i.e., agents) that IMMACCS offers its users, and the manner in which these tools can be applied. Finally, the performance of IMMACCS during the Urban Warrior Advanced Warfighting Experiment held in California in March, 1999, is discussed from an operational viewpoint

    Supernova Cosmology and the ESSENCE project

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    The proper usage of Type Ia supernovae (SNe Ia) as distance indicators has revolutionized cosmology, and added a new dominant component to the energy density of the Universe, dark energy. Following the discovery and confirmation era, the currently ongoing SNe Ia surveys aim to determine the properties of the dark energy. ESSENCE is a five year ground-based supernova survey aimed at finding and characterizing 200 SNe Ia in the redshift domain z=[0.2-0.8]. The goal of the project is to put constraints on the equation of state parameter, w, of the dark energy with an accuracy of <10%. This paper presents these ongoing efforts in the context of the current developments in observational cosmology.Comment: Submitted to EPS1

    Predictive Nomogram for Recurrence following Surgery for Nonmetastatic Renal Cell Cancer with Tumor Thrombus

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    Purpose Following surgery for nonmetastatic renal cell carcinoma with tumor thrombus the risk of recurrence is significant but variable among patients. The purpose of this study was to develop and validate a predictive nomogram for individual estimation of recurrence risk following surgery for renal cell carcinoma with venous tumor thrombus. Materials and Methods Comprehensive data were collected on patients with nonmetastatic renal cell carcinoma and thrombus treated at a total of 5 institutions from 2000 to 2013. Independent predictors of recurrent renal cell carcinoma from a competing risks analysis were developed into a nomogram. Predictive accuracy was compared between the development and validation cohorts, and between the nomogram and the UISS (UCLA Integrated Staging System, SSIGN (Stage, Size, Grade and Necrosis) and Sorbellini models. Results A total of 636 patients were analyzed, including the development cohort of 465 and the validation cohort of 171. Independent predictors, including tumor diameter, body mass index, preoperative hemoglobin less than the lower limit of normal, thrombus level, perinephric fat invasion and nonclear cell histology, were developed into a nomogram. Estimated 5-year recurrence-free survival was 49% overall. Five-year recurrence-free survival in patients with 0, 1, 2 and more than 2 risk factors was 77%, 53%, 47% and 20%, respectively. Predictive accuracy was similar in the development and validation cohorts (AUC 0.726 and 0.724, respectively). Predictive accuracy of the thrombus nomogram was higher than that of the UISS (AUC 0.726 vs 0.595, p = 0.001), SSIGN (AUC 0.713 vs 0.612, p = 0.04) and Sorbellini models (AUC 0.709 vs 0.638, p = 0.02). Conclusions We present a predictive nomogram for postoperative recurrence in patients with nonmetastatic renal cell carcinoma with venous thrombus. Improving individual postoperative risk assessment may allow for better design and analysis of future adjuvant clinical trials

    dSir2 and Dmp53 interact to mediate aspects of CR‐dependent life span extension in D. melanogaster

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    Calorie Restriction (CR) is a well established method of extending life span in a variety of organisms. In the fruit fly D. melanogaster, CR is mediated at least in part by activation of dSir2. In mammalian systems, one of the critical targets of Sir2 is the tumor suppressor p53. This deacetylation of p53 by Sir2 leads to inhibition of p53's transcriptional activity. We have recently shown that inhibition of Dmp53 activity in the fly brain through the use of dominant-negative (DN) constructs that inhibit DNA- binding can extend life span. This life span extension appears to be related to CR, as CR and DN-Dmp53 do not display additive effects on life span. Here we report that life span extension by DN-Dmp53 expression is highly dynamic and can be achieved even when DN-Dmp53 is expressed later in life. In addition, we demonstrate that life span extension by activation of dSir2 and DN-Dmp53 expression are not additive. Furthermore, we show that dSir2 physically interacts with Dmp53 and can deacetylate Dmp53-derived peptides. Taken together, our data demonstrate that Dmp53 is a down stream target of dSir2 enzymatic activity and mediates some aspects of the life span extending effects of CR

    The IRAC point response function in the warm Spitzer mission

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    The Infrared Array Camera (IRAC) is now the only science instrument in operation on the Spitzer Space Telescope. The 3.6 and 4.5 ”m channels are temperature-stabilized at ~28.7K, and the sensitivity of IRAC is nearly identical to what it was in the cryogenic mission. The instrument point response function (PRF) is a set of values from which one can determine the point spread function (PSF) for a source at any position in the field, and is dependent on the optical characteristics of the telescope and instrument as well as the detector sampling and pixel response. These data are necessary when performing PSF-fitting photometry of sources, for deconvolving an IRAC image, subtracting out a bright source in a field, or for estimating the flux of a source that saturates the detector. Since the telescope and instrument are operating at a higher temperature in the post-cryogenic mission, we re-derive the PRFs for IRAC from measurements obtained after the warm mission temperature set point and detector biases were finalized and compare them to the 3.6 and 4.5 ”m PRFs determined during the cryogenic mission to assess any changes
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