The Structure of Political Discussion Networks: A Model for the Analysis of Online Deliberation

2010 ◽  
Vol 25 (2) ◽  
pp. 230-243 ◽  
Author(s):  
Sandra Gonzalez-Bailon ◽  
Andreas Kaltenbrunner ◽  
Rafael E Banchs
Keyword(s):  
Structural Features ◽  
Political Discussion ◽  
Hierarchical Networks ◽  
Internet Technologies ◽  
Discussion Threads ◽  
Online Deliberation ◽  
Political Deliberation ◽  
Using Data

This paper shows that online political discussion networks are, on average, wider and deeper than the networks generated by other types of discussions: they engage a larger number of participants and cascade through more levels of nested comments. Using data collected from the Slashdot forum, this paper reconstructs the discussion threads as hierarchical networks and proposes a model for their comparison and classification. In addition to the substantive topic of discussion, which corresponds to the different sections of the forum (such as Developers, Games, or Politics), we classify the threads according to structural features like the maximum number of comments at any level of the network (i.e. the width) and the number of nested layers in the network (i.e. the depth). We find that political discussion networks display a tendency to cluster around the area that corresponds to wider and deeper structures, showing a significant departure from the structure exhibited by other types of discussions. We propose using this model to create a framework that allows the analysis and comparison of different internet technologies for the promotion of political deliberation.

General Screening of Surface Alloys for Catalysis

2020 ◽  
Author(s):  
Matthew Montemore ◽  
Chukwudi F. Nwaokorie ◽  
Gbolade O. Kayode
Keyword(s):  
Electronic Structure ◽  
Catalytic Performance ◽  
Structural Features ◽  
Design Parameters ◽  
Surface Alloys ◽  
Catalytic Surfaces ◽  
Challenges And Opportunities ◽  
Adsorption Energies ◽  
Using Data ◽  
Structure Properties

Intensive research in catalysis has resulted in design parameters for many important catalytic reactions; however, designing new catalysts remains difficult, partly due to the time and expense needed to screen a large number of potential catalytic surfaces. Here, we create a general, efficient model that can be used to screen surface alloys for many reactions without any quantum-based calculations. This model allows the prediction of the adsorption energies of a variety of species (explicitly shown for C, N, O, OH, H, S, K, F) on metal alloy surfaces that include combinations of nearly all of the d-block metals. We find that a few simple structural features, chosen using data-driven techniques and physical understanding, can be used to predict electronic structure properties. These electronic structure properties are then used to predict adsorption energies, which are in turn used to predict catalytic performance. This framework is interpretable and gives insight into how underlying structural features affect adsorption and catalytic performance. We apply the model to screen more than 10<sup>7</sup> unique surface sites on approximately 10<sup>6</sup> unique surfaces for 7 important reactions. We identify novel surfaces with high predicted catalytic performance, and demonstrate challenges and opportunities in catalyst development using surface alloys. This work shows the utility of a general, reusable model that can be applied in new contexts without requiring new data to be generated.<br>

Single Crystal Automated Refinement (SCAR): A Data-Driven Method for Solving Inorganic Structures

2019 ◽  
Author(s):  
Gayatri Viswanathan ◽  
Anton Oliynyk ◽  
Erin Antono ◽  
Julia Ling ◽  
Bryce Meredig ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Single Crystal ◽  
Structural Features ◽  
Single Crystal Diffraction ◽  
Data Set ◽  
Inorganic Solids ◽  
Automatic Structure ◽  
Structure Solution ◽  
Extended Solids ◽  
Using Data

<p>Single crystal diffraction is one of the most common experimental techniques in chemistry for determining a crystal structure. However, the process of crystal structure solution and refinement is not always straightforward. Methods to simplify and rationalize the path to the most optimal crystal structure model have been incorporated into various data processing and crystal structure solution software, with the focus generally on aiding macromolecular or protein structure solution. In this work, we propose a new method that uses single crystal data to solve the crystal structures of inorganic, extended solids called “Single Crystal Automated Refinement (<i>SCAR</i>).” The approach was developed using data mining and machine-learning methods and considers several structural features common in inorganic solids, like atom assignment based on physically reasonable distances, atomic statistical mixing, and crystallographic site deficiency. The output is a tree of possible solutions for the data set with a corresponding fit score indicating the most reasonable crystal structure. Here, the foundation for <i>SCAR</i> is presented followed by the implementation of <i>SCAR</i> to solve two newly synthesized and previously unreported phases, ZrAu<sub>0.5</sub>Os<sub>0.5</sub> and Nd<sub>4</sub>Mn<sub>2</sub>AuGe<sub>4</sub>. The structure solutions are found to be comparable with manually solving the data set, including the same refined mixed occupancies and atomic deficiency, supporting the validity of this automatic structure solution method. The proposed <i>SCAR</i> program is thusly verified to be a fast and reliable assistant in solving even complex single crystal diffraction data for extended inorganic solids.</p>

Single Crystal Automated Refinement (SCAR): A Data-Driven Method for Solving Inorganic Structures

2019 ◽  
Author(s):  
Gayatri Viswanathan ◽  
Anton Oliynyk ◽  
Erin Antono ◽  
Julia Ling ◽  
Bryce Meredig ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Single Crystal ◽  
Structural Features ◽  
Single Crystal Diffraction ◽  
Data Set ◽  
Inorganic Solids ◽  
Automatic Structure ◽  
Structure Solution ◽  
Extended Solids ◽  
Using Data

<p>Single crystal diffraction is one of the most common experimental techniques in chemistry for determining a crystal structure. However, the process of crystal structure solution and refinement is not always straightforward. Methods to simplify and rationalize the path to the most optimal crystal structure model have been incorporated into various data processing and crystal structure solution software, with the focus generally on aiding macromolecular or protein structure solution. In this work, we propose a new method that uses single crystal data to solve the crystal structures of inorganic, extended solids called “Single Crystal Automated Refinement (<i>SCAR</i>).” The approach was developed using data mining and machine-learning methods and considers several structural features common in inorganic solids, like atom assignment based on physically reasonable distances, atomic statistical mixing, and crystallographic site deficiency. The output is a tree of possible solutions for the data set with a corresponding fit score indicating the most reasonable crystal structure. Here, the foundation for <i>SCAR</i> is presented followed by the implementation of <i>SCAR</i> to solve two newly synthesized and previously unreported phases, ZrAu<sub>0.5</sub>Os<sub>0.5</sub> and Nd<sub>4</sub>Mn<sub>2</sub>AuGe<sub>4</sub>. The structure solutions are found to be comparable with manually solving the data set, including the same refined mixed occupancies and atomic deficiency, supporting the validity of this automatic structure solution method. The proposed <i>SCAR</i> program is thusly verified to be a fast and reliable assistant in solving even complex single crystal diffraction data for extended inorganic solids.</p>

‘The moral power of the citizen questioner’: scrutinizing the value of audience questions on the ABC’s Q&A

2016 ◽  
Vol 161 (1) ◽  
pp. 120-131 ◽  
Author(s):  
Belinda Eslick
Keyword(s):  
Public Sphere ◽  
Political Engagement ◽  
Direct Access ◽  
Political Discussion ◽  
Political News ◽  
Current Affairs ◽  
Moral Power ◽  
Low Levels ◽  
Using Data

The Australian Broadcasting Corporation’s (ABC) weekly political discussion program Q&A aims to make Australian politics more engaging to ordinary citizens by allowing direct access between ‘punters’ and ‘pollies’. The program is a unique forum in the Australian political public sphere where citizens (represented by the studio audience) are awarded greater power than in conventional political news and current affairs formats. However, some critics have argued that the program is, among other things, overly editorialized and contrived and more autocratic than democratic, where the power of the citizen is superficial only. Using data gathered from focus groups, this article explores attitudes toward the role of the audience questioners on Q&A – one of the defining ‘democratizing’ features of the program. Considering responses of viewers with both high and low levels of political engagement has led to interesting findings about how motivations for watching Q&A, as well as expectations about how it should function, differ according to viewers’ pre-existing level of political interest.

Examination of Synthetic Murataite Structure Using Data of Mossbauer Spectroscopy

2003 ◽  
Vol 807 ◽  
Author(s):  
Vadim S. Urusov ◽  
Vyacheslav S. Rusakov ◽  
Sergey V. Yudintsev ◽  
Sergey V. Stefanovsky
Keyword(s):  
Mössbauer Spectroscopy ◽  
Mossbauer Spectroscopy ◽  
Structural Features ◽  
High Level Waste ◽  
Crystal Chemical ◽  
Chemical Formula ◽  
Crystal Chemical Formula ◽  
Mößbauer Spectroscopy ◽  
Using Data ◽  
High Level

ABSTRACTMurataite-based ceramics were recently suggested as promising matrices for immobilization of rare earths and actinides from high-level waste (HLW). Nevertheless, the crystal-chemical formula of the phase has not been accurately determined yet. We have examined structural features of murataite with Mössbauer spectroscopy. Initial batches were prepared from CaO, Al2O3, Fe2O3, MnO2, ZrO2, TiO2, ZrO2, and UO2. Mixtures were melted in platinum crucibles in a resistive furnace in air at 1450°C for 1 h followed by cooling to 1000°C at the rate of 10°C/min. and final cooling down with the furnace switched-off. Study with XRD, SEM, and TEM showed the samples are composed of two co-existing murataite-type phases with five- and eight-fold elementary fluorite cells. To investigate the valence and structural position of iron ions, Mössbauer spectroscopy on 7Fe nuclei in geometry “on absorption” was used. The data obtained let us conclude that in both murataite varieties trivalent iron is distributed almost statistically (3:1) between B octahedra and C five-vertex polyhedra, while tetrahedral sites T are probably not populated. Taking into account these suggestions, the idealized crystal chemical formula of synthetic murataites can be simplified to A3[8]B6[6]C2[5]O22-x/2. Recalculation of chemical analyses to atomic numbers results in the conclusion that average cation valence for murataites is 3.33. Then, calculation for the generalized formula M11O22-x/2 (M=A,B,C) gives a value x/2 = 3.7, i.e., the number of O atoms in the formula is 22–3.7 = 18.3. Final conclusions on the murataite formulae have to be verified by direct structural research on a single crystal.

scholarly journals Microbiological indicators for assessing the ecological status of freshwater lakes in Buryatia

2021 ◽  
Vol 885 (1) ◽  
pp. 012067
Author(s):  
S V Zaitseva ◽  
O P Dagurova ◽  
L P Kozyreva
Keyword(s):  
Microbial Communities ◽  
Anthropogenic Impact ◽  
High Throughput Sequencing ◽  
Ecological Status ◽  
Structural Features ◽  
Freshwater Lakes ◽  
Environmental Status ◽  
Freshwater Bodies ◽  
Using Data ◽  
Microbiological Indicators

Abstract Possible complex approaches for assessing the condition of freshwater lakes using data on microbial diversity, obtained by high-throughput sequencing, were considered. The structural features of microbial communities, associated with increased anthropogenic impact, have been revealed. We identified some microbial taxa, which can be considered as indicators of the environmental status of freshwater bodies.

scholarly journals General Screening of Surface Alloys for Catalysis

2020 ◽  
Author(s):  
Matthew Montemore ◽  
Chukwudi F. Nwaokorie ◽  
Gbolade O. Kayode
Keyword(s):  
Electronic Structure ◽  
Catalytic Performance ◽  
Structural Features ◽  
Design Parameters ◽  
Surface Alloys ◽  
Catalytic Surfaces ◽  
Challenges And Opportunities ◽  
Adsorption Energies ◽  
Using Data ◽  
Structure Properties

Intensive research in catalysis has resulted in design parameters for many important catalytic reactions; however, designing new catalysts remains difficult, partly due to the time and expense needed to screen a large number of potential catalytic surfaces. Here, we create a general, efficient model that can be used to screen surface alloys for many reactions without any quantum-based calculations. This model allows the prediction of the adsorption energies of a variety of species (explicitly shown for C, N, O, OH, H, S, K, F) on metal alloy surfaces that include combinations of nearly all of the d-block metals. We find that a few simple structural features, chosen using data-driven techniques and physical understanding, can be used to predict electronic structure properties. These electronic structure properties are then used to predict adsorption energies, which are in turn used to predict catalytic performance. This framework is interpretable and gives insight into how underlying structural features affect adsorption and catalytic performance. We apply the model to screen more than 10<sup>7</sup> unique surface sites on approximately 10<sup>6</sup> unique surfaces for 7 important reactions. We identify novel surfaces with high predicted catalytic performance, and demonstrate challenges and opportunities in catalyst development using surface alloys. This work shows the utility of a general, reusable model that can be applied in new contexts without requiring new data to be generated.<br>

scholarly journals Boundary Control as Gatekeeping in Facebook Groups

2021 ◽  
Vol 9 (4) ◽  
pp. 73-81 ◽  
Author(s):  
Sanna Malinen
Keyword(s):  
Public Sphere ◽  
Group Membership ◽  
Political Discussion ◽  
Group Norms ◽  
Digital Networks ◽  
Protecting Group ◽  
Face To Face ◽  
Media Control ◽  
Using Data ◽  
Global Platform

Facebook groups host user-created communities on Facebook’s global platform, and their administrative structure consists of members, volunteer moderators, and governance mechanisms developed by the platform itself. This study presents the viewpoints of volunteers who moderate groups on Facebook that are dedicated to political discussion. It sheds light on how they enact their day-to-day moderation work, from platform administration to group membership, while acknowledging the demands that come from both these tasks. As volunteer moderators make key decisions about content, their work significantly shapes public discussion in their groups. Using data obtained from 15 face-to-face interviews, this qualitative study sheds light on volunteer moderation as a means of media control in complex digital networks. The findings show that moderation concerns not just the removal of content or contacts but, most importantly, it is about protecting group norms by controlling who has the access to the group. Facebook’s volunteer moderators have power not only to guide discussion but, above all, to decide who can participate in it, which makes them important gatekeepers of the digital public sphere.

Getting political on social network sites: Exploring online political discourse on Facebook

First Monday ◽  
2009 ◽  
Author(s):  
Matthew J. Kushin ◽  
Kelin Kitchener
Keyword(s):  
Social Network ◽  
Behavior Analysis ◽  
Political Discourse ◽  
Social Network Sites ◽  
Large Majority ◽  
Political Discussion ◽  
Social Network Site ◽  
Internet Technologies ◽  
Network Site ◽  
The Social

This study explores use of the social network site Facebook for online political discussion. Online political discussion has been criticized for isolating disagreeing persons from engaging in discussion and for having an atmosphere of uncivil discussion behavior. Analysis reveals the participation of disagreeing parties within the discussion with the large majority of posters (73 percent) expressing support for the stated position of the Facebook group, and a minority of posters (17 percent) expressing opposition to the position of the group. Despite the presence of uncivil discussion posting within the Facebook group, the large majority of discussion participation (75 percent) is devoid of flaming. Results of this study provide important groundwork and raise new questions for study of online political discussion as it occurs in the emergent Internet technologies of social network sites.

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