1,568 research outputs found
Antenna servo control system characterization: Rate loop analysis for 34-m antenna at DSS 15
The elevation and azimuth servo rate loops at the 34-m High Efficiency Deep Space Station 15 (DSS 15) are described. Time and frequency response performance criteria were measured. The results are compared to theoretically deduced performance criteria. Unexpected anomalies in the frequency response are observed and identified
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Ly9 (CD229) Cell-Surface Receptor is Crucial for the Development of Spontaneous Autoantibody Production to Nuclear Antigens
The Signaling Lymphocyte Activation Molecule Family (SLAMF) genes, which encode cell-surface receptors that modulate innate and adaptive immune responses, lay within a genomic region of human and mouse chromosome 1 that confers a predisposition for the development of systemic lupus erythematosus (SLE). Herein, we demonstrate that the SLAMF member Ly9 arises as a novel receptor contributing to the reinforcement of tolerance. Specifically, Ly9-deficient mice spontaneously developed features of systemic autoimmunity such as the production of anti-nuclear antibodies (ANA), -dsDNA, and -nucleosome autoantibodies, independently of genetic background [(B6.129) or (BALB/c.129)]. In aged (10- to 12-month-old) Ly9−/− mice key cell subsets implicated in autoimmunity were expanded, e.g., T follicular helper (Tfh) as well as germinal center (GC) B cells. More importantly, in vitro functional experiments showed that Ly9 acts as an inhibitory receptor of IFN-γ producing CD4+ T cells. Taken together, our findings reveal that the Ly9 receptor triggers cell intrinsic safeguarding mechanisms to prevent a breach of tolerance, emerging as a new non-redundant inhibitory cell-surface receptor capable of disabling autoantibody responses
Design of an Interlock Module for Use in a Globally Asynchronous, Locally Synchronous Design Methodology
As the number of transistors on a single integrated circuit approach a billion, the problems of clock distribution, power consumption, multiple clock domains, meeting timing requirements, and reuse of subsystem designs grow ever more difficult. Coordinating a billion transistors with the present design methodologies will require hundreds of years of engineering time. A new design methodology is needed. The GALS (Globally Asynchronous Locally Synchronous) approach, that blends clockless and clocked subsystems is a strong contender
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SAP-Dependent and -Independent Regulation of Innate T Cell Development Involving SLAMF Receptors
Signaling lymphocytic activation molecule (SLAM)-associated protein (SAP) plays an essential role in the immune system mediating the function of several members of the SLAM family (SLAMF) of receptors, whose expression is essential for T, NK, and B-cell responses. Additionally, the expression of SAP in double-positive thymocytes is mandatory for natural killer T (NKT) cells and, in mouse, for innate CD8+ T cell development. To date, only two members of the SLAMF of receptors, Slamf1 and Slamf6, have been shown to positively cooperate during NKT cell differentiation in mouse. However, it is less clear whether other members of this family may also participate in the development of these innate T cells. Here, we show that Slamf[1 + 6]−/− and Slamf[1 + 5 + 6]−/−B6 mice have ~70% reduction of NKT cells compared to wild-type B6 mice. Unexpectedly, the proportion of innate CD8+ T cells slightly increased in the Slamf[1 + 5 + 6]−/−, but not in the Slamf[1 + 6]−/− strain, suggesting that Slamf5 may function as a negative regulator of innate CD8+ T cell development. Accordingly, Slamf5−/− B6 mice showed an exclusive expansion of innate CD8+ T cells, but not NKT cells. Interestingly, the SAP-independent Slamf7−/− strain showed an expansion of both splenic innate CD8+ T cells and thymic NKT cells. On the other hand, and similar to what was recently shown in Slamf3−/− BALB/c mice, the proportions of thymic promyelocytic leukemia zinc finger (PLZFhi) NKT cells and innate CD8+ T cells significantly increased in the SAP-independent Slamf8−/− BALB/c strain. In summary, these results show that NKT and innate CD8+ T cell development can be regulated in a SAP-dependent and -independent fashion by SLAMF receptors, in which Slamf1, Slamf6, and Slamf8 affect development of NKT cells, and that Slamf5, Slamf7, and Slamf8 affect the development of innate CD8+ T cells
Slamf6 negatively regulates autoimmunity
The nine SLAM family (Slamf) receptors are positive or negative regulators of adaptive and innate immune responses, and of several autoimmune diseases. Here we report that the transfer of Slamf6-/- B6 CD4+ T cells into co-isogenic bm12 mice causes SLE-like autoimmunity with elevated levels of autoantibodies. In addition, significantly higher percentages of Tfh cells and IFN-γ-producing CD4+ cells, as well as GC B cells were observed. Interestingly, the expression of the Slamf6-H1 isoform in Slamf6-/- CD4+ T cells did not induce this lupus-like phenotype. By contrast, Slamf1-/- or Slamf5-/- CD4+ T cells caused the same pathology as WT CD4+ T cells. As the transfer of Slamf [1+6]-/- or Slamf [1+5+6]-/- CD4+ T cells induced WT levels of autoantibodies, the presence of Slamf1 was requisite for the induction of increased levels of autoantibodies by Slamf6-/- CD4+ T cells. We conclude that Slamf6 functions as an inhibitory receptor that controls autoimmune responses
Border Effects in House Prices
This article estimates the effect of the Dutch–German border on house prices. We argue that the difference between house prices at the border indicates the willingness to pay to stay in a country compared to living across the border. After a change in the tax rules in 2001, migration from the Netherlands to Germany increased substantially and the gradient of Dutch house price towards the German border steepened. Combining a German and Dutch real estate dataset and using different estimation strategies, we find that asking prices of comparable housing drop by about 16% when one crosses the Dutch–German border
NASA Products to Enhance Energy Utility Load Forecasting
Existing energy load forecasting tools rely upon historical load and forecasted weather to predict load within energy company service areas. The shortcomings of load forecasts are often the result of weather forecasts that are not at a fine enough spatial or temporal resolution to capture local-scale weather events. This project aims to improve the performance of load forecasting tools through the integration of high-resolution, weather-related NASA Earth Science Data, such as temperature, relative humidity, and wind speed. Three companies are participating in operational testing one natural gas company, and two electric providers. Operational results comparing load forecasts with and without NASA weather forecasts have been generated since March 2010. We have worked with end users at the three companies to refine selection of weather forecast information and optimize load forecast model performance. The project will conclude in 2012 with transitioning documented improvements from the inclusion of NASA forecasts for sustained use by energy utilities nationwide in a variety of load forecasting tools. In addition, Battelle has consulted with energy companies nationwide to document their information needs for long-term planning, in light of climate change and regulatory impacts
Distributed clean energy opportunities for US oil refinery operations
The oil and gas industry is increasingly seeking operational improvements to reduce costs and emissions while improving resilience. This study describes techno-economic analysis of opportunities for distributed energy resources that could be integrated to support oil and gas companies’ economic, environmental, and energy resiliency goals. Specifically, the analysis evaluates solar photovoltaics, wind turbines, battery energy storage, landfill gas, biomass, municipal solid waste-to-energy, solar steam for process heat, combined heat and power, and electrolyzers for hydrogen production at two hypothetical refineries, one located in Louisiana and the other in southern California. These technologies could reduce the sites’ consumption of grid electricity and/or natural gas and thus can help reduce emissions. This study employs the ReOPT tool and System Advisor Model to evaluate the techno-economic potential for clean energy technologies to support refineries in achieving energy goals, including energy cost savings, resiliency, and emissions reductions. Results indicate that the associated costs of emissions reductions via several distributed clean energy technologies are competitive with other emissions reduction strategies such as energy efficiency, reducing flaring, direct carbon capture and sequestration, and markets under certain conditions. There are also cost beneficial opportunities for the use of renewable energy for refining, especially for resilience, depending on local conditions such as resources and utility costs
Toward an Understanding of Synergies and Trade-Offs Between Water, Energy, and Food SDG Targets
Achieving the targets set out in the UN Sustainable Development Goals (SDG) will require committed efforts by nations and organizations over the coming decade. To determine which actions work most harmoniously within funding, infrastructure development, and implementation of three closely aligned goals, we conducted an assessment to identify where the greatest synergies may occur and where conflicting resource needs create trade-offs that may threaten SDG success. The SDGs each have several targets that need to be realized for the goal to be reached. In the present study, we developed a methodology where each target of the SDG 2 (food), 6 (water), and 7 (energy) was analyzed for its input requirements, infrastructure needs, and the risks and benefits for the provision of ecosystem services. Then the targets were compared pairwise and a total score of interaction was calculated to determine different levels of synergies and trade-offs for every pair. In some cases targets were mutually supportive, in other cases there were no interactions among the targets, and for some areas the targets were in conflict with each other. For example, targets 2.5 (maintain genetic diversity), 6.5 (implement integrated water resources management) and 7.a (enhance international cooperation to facilitate access to clean energy) have no conflicts with other targets and have different levels of synergies with most of the other targets. On the contrary, various targets of SDG 2, and especially the target 2.b (correct and prevent trade restrictions), are in slight conflict with other targets by potentially overusing resources needed by other targets or threatening ecosystem services. Our approach confirms the general belief that SDG 6 (water) has the highest number of potential synergies (a total of 124). Thus, achieving the water targets will make it continuously easier to achieve other targets. While the results may need to be adapted for a specific locality or country, overall they provide an improved understanding of the interactions between the targets. The value of the study lies in the quantitative methodology as it can be used as a replicable analysis for any level of work on SDG implementation
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