1,027 research outputs found
Observations of High-Redshift X-Ray Selected Clusters with the Sunyaev-Zel'dovich Array
We report measurements of the Sunyaev-Zel'dovich (SZ) effect in three high-redshift (0.89 ≤ z ≤ 1.03), X-ray selected galaxy clusters. The observations were obtained at 30 GHz during the commissioning period of a new, eight-element interferometer—the Sunyaev-Zel'dovich Array (SZA)—built for dedicated SZ effect observations. The SZA observations are sensitive to angular scales larger than those subtended by the virial radii of the clusters. Assuming isothermality and hydrostatic equilibrium for the intracluster medium and gas-mass fractions consistent with those for clusters at moderate redshift, we calculate electron temperatures, gas masses, and total cluster masses from the SZ data. The SZ-derived masses, integrated approximately to the virial radii, are 1.9^(+0.5)_(-0.4) × 10^(14) M_☉ for Cl J1415.1+3612, 3.4^(+0.6)_(-0.5) × 10^(14) M_☉ for Cl J1429.0+4241, and 7.2^(+1.3)_(-0.9) × 10^(14) M_☉ for Cl J1226.9+3332. The SZ-derived quantities are in good agreement with the cluster properties derived from X-ray measurements
Production of human entorhinal stellate cell-like cells by forward programming shows an important role of Foxp1 in reprogramming
publishedVersio
Benthic diatom monitoring and assessment of freshwater environments: standard methods and future challenges
Fil: Soizic, Morin. National Research Institute of Science and Technology for Environment and Agriculture; FranceFil: Gómez, Nora. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Instituto de Limnología Dr. Raúl A. Ringuelet; ArgentinaFil: Tornés, Elisabet. University of Girona. Institute of Aquatic Ecology; SpainFil: Licursi, Magdalena. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Instituto de Limnología Dr. Raúl A. Ringuelet; ArgentinaFil: Rosebery, Juliette. Aquatic Ecosystems and Global Changes Research Unit; Franc
A Distributed Solution for Visual Sensor Networks to Detect Targets in Crowds
Visual sensor networks (VSNs), a novel concept about fulfilling vision tasks by a network of collaborative visual sensors, has been attracting more and more attentions these days. This thesis introduces some pioneering research on developing a distributed algorithm for VSNs to detect targets in a cluttered scene. The algorithm is aimed to achieve excellent performances on both detection accuracy and energy efficiency.
Based on a statistical model of the cluttered scene, the development starts with a centralized version where all the nodes send visual data to a central node and the central node invokes an iterative prioritization strategy (IPS) to make globally optimal detecting decisions. Although resulting in excellent detection accuracy, the centralized fashion causes poor performance on energy utilization.
The algorithm is then transformed into a distributed version where the entire scene is partitioned into a Voronoi diagram and each node is only responsible for detecting targets inside its local polygon area. There are two challenges in realizing such a transformation. The first challenge is to design an energy-efficient method to exchange visual data among relevant nodes. A “back-projecting” strategy (BBR) is therefore created to tackle this challenge. Instead of sending request to nodes that have relevant data, the method initiates the data communication from source nodes. Each packet of visual data is then relayed towards the place where is located the target corresponding to the visual data. All the relevant data about the target will finally reach there and thereafter can be fused. This strategy enables the parallelism between transmitting visual data and integrating visual data for detection. With this parallelism, knowledge from partial detection results can be used to guide the transmission and therefore improve energy efficiency. The second challenge is to design a method to fuse decisions independently made by each node through small amount of mutual communication. A modified one-shot threshold strategy (MOTS) is proposed to tackle this challenge. By receiving small amount of data from related nodes, a local measure can be constructed to validate or invalidate local decisions. Compared with the centralized algorithm, this distributed algorithm demands less energy cost for a large-scale VSN and at same time sustains satisfactory detection accuracy.
An experiment is presented in the end and the experimental results are analyzed
Simulation verification techniques study. Subsystem simulation validation techniques
Techniques for validation of software modules which simulate spacecraft onboard systems are discussed. An overview of the simulation software hierarchy for a shuttle mission simulator is provided. A set of guidelines for the identification of subsystem/module performance parameters and critical performance parameters are presented. Various sources of reference data to serve as standards of performance for simulation validation are identified. Environment, crew station, vehicle configuration, and vehicle dynamics simulation software are briefly discussed from the point of view of their interfaces with subsystem simulation modules. A detailed presentation of results in the area of vehicle subsystems simulation modules is included. A list of references, conclusions and recommendations are also given
Public support to food security in India, Brazil and South Africa: Elements for a policy dialogue
[Introduction ...] Following this introduction, Section 2 presents the conceptual framework on food security that guides this study, and offers succinct data on the three countries based on leading international measures. Section 3 offers a general presentation of the food-security policy agendas, highlighting their broad comparative elements. It explores the leading conceptions, orientations and measurements used. Section 4 deals with the rights-based approach to food security, focusing on the current legal apparatus and accountability mechanisms. Section 5 examines how different stakeholders, particularly civil-society organisations and various levels of government, take part in public interventions. Section 6 considers food production, highlighting two particular issues: how the promotion of small-scale farming is taken into account in food-security policy, and how environmental matters are considered in public support for food production. Section 7 explores major public initiatives on access to food, and draws attention to some relevant experiences of cash transfers, in-kind transfers and public works. Section 8 assesses key challenges and achievements relating to food security in the three countries. Section 9 points out the main issues that could be explored in further policy dialogue. Finally, a summary table of the major themes considered throughout the text is provided in the Annex
Activation of the pro-resolving receptor Fpr2 attenuates inflammatory microglial activation
Poster number: P-T099
Theme: Neurodegenerative disorders & ageing
Activation of the pro-resolving receptor Fpr2 reverses inflammatory microglial activation
Authors: Edward S Wickstead - Life Science & Technology University of Westminster/Queen Mary University of London
Inflammation is a major contributor to many neurodegenerative disease (Heneka et al. 2015). Microglia, as the resident immune cells of the brain and spinal cord, provide the first line of immunological defence, but can become deleterious when chronically activated, triggering extensive neuronal damage (Cunningham, 2013). Dampening or even reversing this activation may provide neuronal protection against chronic inflammatory damage. The aim of this study was to determine whether lipopolysaccharide (LPS)-induced inflammation could be abrogated through activation of the receptor Fpr2, known to play an important role in peripheral inflammatory resolution. Immortalised murine microglia (BV2 cell line) were stimulated with LPS (50ng/ml) for 1 hour prior to the treatment with one of two Fpr2 ligands, either Cpd43 or Quin-C1 (both 100nM), and production of nitric oxide (NO), tumour necrosis factor alpha (TNFα) and interleukin-10 (IL-10)
were monitored after 24h and 48h. Treatment with either Fpr2 ligand significantly suppressed LPS-induced production of NO or TNFα after both 24h and 48h exposure, moreover Fpr2 ligand treatment significantly enhanced production of IL-10 48h post-LPS treatment. As we have previously shown Fpr2 to be coupled to a number of intracellular signaling pathways (Cooray et al. 2013), we investigated potential signaling
responses. Western blot analysis revealed no activation of ERK1/2, but identified a rapid and potent activation of p38 MAP kinase in BV2 microglia following stimulation with Fpr2 ligands. Together, these data indicate the possibility of exploiting immunomodulatory strategies for the treatment of neurological diseases, and highlight in particular the important potential of resolution mechanisms as novel therapeutic targets in neuroinflammation.
References
Cooray SN et al. (2013). Proc Natl Acad Sci U S A 110: 18232-7.
Cunningham C (2013). Glia 61: 71-90.
Heneka MT et al. (2015). Lancet Neurol 14: 388-40
Context-Aware Kubernetes Scheduler for Edge-native Applications on 5G
This paper is an extension of work originally presented in SoftCOM 2019 [1]. The novelty of this work reside in its focused improvement of our scheduling algorithm towards its usage on a real 5G infrastructure. Industrial IoT applications are often designed to run in a distributed way on the devices and controller computers with strict service requirements for the nodes and the links between them. 5G, especially in concomitance with Edge Computing, will provide the desired level of connectivity for these setups and it will permit to host application run-time components in edge clouds. However, allocation of the edge cloud resources for Industrial IoT (IIoT) applications, is still commonly solved by rudimentary scheduling techniques (i.e. simple strategies based on CPU usage and device readiness, employing very few dynamic information). Orchestrators inherited from the cloud computing, like Kubernetes, are not satisfying to the requirements of the aforementioned applications and are not optimized for the diversity of devices which are often also limited in capacity. This design is especially slow in reacting to the environmental changes. In such circumstances, in order to provide a proper solution using these tools, we propose to take the physical, operational and network parameters (thus the full context of the IIoT application) into consideration, along with the software states and orchestrate the applications dynamically
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