48 research outputs found
A customisable pipeline for continuously harvesting socially-minded Twitter users
On social media platforms and Twitter in particular, specific classes of
users such as influencers have been given satisfactory operational definitions
in terms of network and content metrics.
Others, for instance online activists, are not less important but their
characterisation still requires experimenting.
We make the hypothesis that such interesting users can be found within
temporally and spatially localised contexts, i.e., small but topical fragments
of the network containing interactions about social events or campaigns with a
significant footprint on Twitter.
To explore this hypothesis, we have designed a continuous user profile
discovery pipeline that produces an ever-growing dataset of user profiles by
harvesting and analysing contexts from the Twitter stream.
The profiles dataset includes key network and content-based users metrics,
enabling experimentation with user-defined score functions that characterise
specific classes of online users.
The paper describes the design and implementation of the pipeline and its
empirical evaluation on a case study consisting of healthcare-related campaigns
in the UK, showing how it supports the operational definitions of online
activism, by comparing three experimental ranking functions. The code is
publicly available.Comment: Procs. ICWE 2019, June 2019, Kore
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A novel geotechnical/geostatistical approach for exploration and production of natural gas from multiple geologic strata, Phase 1. Volume 2, Geology and engineering
This research program has been designed to develop and verify a unique geostatistical approach for finding natural gas resources. The project has been conducted by Beckley College, Inc., and BDM Engineering Services Company (BDMESC) under contract to the US Department of Energy (DOE), Morgantown Energy Technology Center (METC). This section, Volume II, contains a detailed discussion of the methodology used and the geological and production information collected and analyzed for this study. A companion document, Volume 1, provides an overview of the program, technique and results of the study. In combination, Volumes I and II cover the completion of the research undertaken under Phase I of this DOE project, which included the identification of five high-potential sites for natural gas production on the Eccles Quadrangle, Raleigh County, West Virginia. Each of these sites was selected for its excellent potential for gas production from both relatively shallow coalbeds and the deeper, conventional reservoir formations
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A novel geotechnical/geostatistical approach for exploration and production of natural gas from multiple geologic strata, Phase 1. Volume 1, Overview
This research program has been designed to develop and verify a unique geostatistical approach for finding natural gas resources. The research has been conducted by Beckley College, Inc. (Beckley) and BDM Engineering Services Company (BDMESC) under contract to the US Department of Energy (DOE), Morgantown Energy Technology Center. Phase 1 of the project consisted of compiling and analyzing relevant geological and gas production information in selected areas of Raleigh County, West Virginia, ultimately narrowed to the Eccles, West Virginia, 7 {1/2} minute Quadrangle. The Phase 1 analysis identified key parameters contributing to the accumulation and production of natural gas in Raleigh County, developed analog models relating geological factors to gas production, and identified specific sites to test and verify the analysis methodologies by drilling. Based on the Phase 1 analysis, five sites have been identified with high potential for economic gas production. Phase 2 will consist of drilling, completing, and producing one or more wells at the sites identified in the Phase 1 analyses. The initial well is schedules to the drilled in April 1991. This report summarizes the results of the Phase 1 investigations. For clarity, the report has been prepared in two volumes. Volume 1 presents the Phase 1 overview; Volume 2 contains the detailed geological and production information collected and analyzed for this study
Mice Exposed to Combined Chronic Low-Dose Irradiation and Modeled Microgravity Develop Long-Term Neurological Sequelae
Spaceflight poses many challenges for humans. Ground-based analogs typically focus on single parameters of spaceflight and their associated acute effects. This study assesses the long-term transcriptional effects following single and combination spaceflight analog conditions using the mouse model: simulated microgravity via hindlimb unloading (HLU) and/or low-dose γ-ray irradiation (LDR) for 21 days, followed by 4 months of readaptation. Changes in gene expression and epigenetic modifications in brain samples during readaptation were analyzed by whole transcriptome shotgun sequencing (RNA-seq) and reduced representation bisulfite sequencing (RRBS). The results showed minimal gene expression and cytosine methylation alterations at 4 months readaptation within single treatment conditions of HLU or LDR. In contrast, following combined HLU+LDR, gene expression and promoter methylation analyses showed multiple altered pathways involved in neurogenesis and neuroplasticity, the regulation of neuropeptides, and cellular signaling. In brief, neurological readaptation following combined chronic LDR and HLU is a dynamic process that involves pathways that regulate neuronal function and structure and may lead to late onset neurological sequelae
Challenges and considerations for single-cell and spatially resolved transcriptomics sample collection during spaceflight
15 p.-2 fig.-3 tab.Single-cell RNA sequencing (scRNA-seq) and spatially resolved transcriptomics (SRT) have experienced rapid development in recent years. The findings of spaceflight-based scRNA-seq and SRT investigations are likely to improve our understanding of life in space and our comprehension of gene expression in various cell systems and tissue dynamics. However, compared to their Earth-based counterparts, gene expression experiments conducted in spaceflight have not experienced the same pace of development. Out of the hundreds of spaceflight gene expression datasets available, only a few used scRNA-seq and SRT. In this perspective piece, we explore the growing importance of scRNA-seq and SRT in space biology and discuss the challenges and considerations relevant to robust experimental design to enable growth of these methods in the field.H.C., P.M., D.B., R.H., N.J.S., J.B., and S.G. are members of the ESA Space Omics Topical Team, funded by the ESA grant/contract 4000131202/20/NL/PG/pt “Space Omics: Towards an integrated ESA/NASA – omics database for spaceflight and ground facilities experiments” awarded to R.H., which was the main funding source for this work. H.C. is also supported by the Horizon Centre for Doctoral Training at the University of Nottingham (UKRI grant no. EP/S023305/1). S.G. is supported by the Swedish Research Council VR grant 2020-04864. E.G.O. is supported through NASA Postdoctoral Fellowship 80NSSC21K0316.Peer reviewe
Mammalian and Invertebrate Models as Complementary Tools for Gaining Mechanistic Insight on Muscle Responses to Spaceflight
Bioinformatics approaches have proven useful in understanding biological responses to spaceflight. Spaceflight experiments remain resource intensive and rare. One outstanding issue is how to maximize scientific output from a limited number of omics datasets from traditional animal models including nematodes, fruitfly, and rodents. The utility of omics data from invertebrate models in anticipating mammalian responses to spaceflight has not been fully explored. Hence, we performed comparative analyses of transcriptomes of soleus and extensor digitorum longus (EDL) in mice that underwent 37 days of spaceflight. Results indicate shared stress responses and altered circadian rhythm. EDL showed more robust growth signals and Pde2a downregulation, possibly underlying its resistance to atrophy versus soleus. Spaceflight and hindlimb unloading mice shared differential regulation of proliferation, circadian, and neuronal signaling. Shared gene regulation in muscles of humans on bedrest and space flown rodents suggest targets for mitigating muscle atrophy in space and on Earth. Spaceflight responses of C. elegans were more similar to EDL. Discrete life stages of D. melanogaster have distinct utility in anticipating EDL and soleus responses. In summary, spaceflight leads to shared and discrete molecular responses between muscle types and invertebrate models may augment mechanistic knowledge gained from rodent spaceflight and ground-based studies
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The circulating air barrier: Effective prevention of liquid contaminant movement through soil
Objectives of this task included design, modeling, selection of drilling and surface processing equipment, and development of test procedures and cost estimates for conducting a cold test demonstration of the Circulating Air Barrier (CAB) process. The demonstration configuration is scaled to a prototype CAB system designed specifically for the C Tank Farm at the Hanford Site. The CAB system is designed to function as a containment barrier to prevent contamination of the water table located approximately 200 feet below the base of the C-Tank-Farm underground storage tanks. The CAB system is a desiccant-type barrier designed to prevent the migration of liquid contaminants toward the ground water by using an air circulation and processing system to lower the saturation in a targeted subsurface zone below the saturation level required for liquid flow through that zone. The CAB system offers several important advantages, including the fact that it is a non-physical confinement technology, it has an active monitoring and leak detection capability, it is based on proven, commercially available equipment and oil and gas technologies; it has excellent potential for emergency response and rapid deployment; and offers high potential for integration with other remediation technologies. Demonstration- and full-scale CAB systems have been designed for the Hanford Site as part of this task
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Site selection, drilling, and completion of two horizontal wells in the Devonian Shales of West Virginia
This report presents a summary of the geologic site selection studies, planning, drilling, completing, stimulating, and testing of two horizontal wells drilled in the Devonian Shales of the Appalachian Basin in West Virginia. Each horizontal well was designed and managed by BDM as the prime contractor to the Department of Energy. The first well was drilled with industry partner Cabot Oil and Gas Corporation in Putnam County, West Virginia. The second well was drilled with Consolidated Natural Gas Company in Calhoun County, West Virginia. This report summarizes four reports prepared by BDM which detail the site selection rationale and the drilling and completion operations of each well. Each horizontal well is currently producing commercial quantities of hydrocarbons. The successful application of horizontal well technology represent continued development of the technology for application to tight and unconventional natural gas resources of the United States. Continued technology development is expected to ultimately result in commercial horizontal well drilling activity by industry in the Appalachian Basin