Participant Perceptions of Twitter Research Ethics

Social computing systems such as Twitter present new research sites that have provided billions of data points to researchers. However, the availability of public social media data has also presented ethical challenges. As the research community works to create ethical norms, we should be considering users’ concerns as well. With this in mind, we report on an exploratory survey of Twitter users’ perceptions of the use of tweets in research. Within our survey sample, few users were previously aware that their public tweets could be used by researchers, and the majority felt that researchers should not be able to use tweets without consent. However, we find that these attitudes are highly contextual, depending on factors such as how the research is conducted or disseminated, who is conducting it, and what the study is about. The findings of this study point to potential best practices for researchers conducting observation and analysis of public data

Role of SPAK-NKCC1 signaling cascade in the choroid plexus blood-CSF barrier damage after stroke.

This is the final version. Available from BMC via the DOI in this record. Availability of data and materials: Supporting data and information about used material are available from the corresponding author on reasonable request.BACKGROUND: The mechanisms underlying dysfunction of choroid plexus (ChP) blood-cerebrospinal fluid (CSF) barrier and lymphocyte invasion in neuroinflammatory responses to stroke are not well understood. In this study, we investigated whether stroke damaged the blood-CSF barrier integrity due to dysregulation of major ChP ion transport system, Na+-K+-Cl- cotransporter 1 (NKCC1), and regulatory Ste20-related proline-alanine-rich kinase (SPAK). METHODS: Sham or ischemic stroke was induced in C57Bl/6J mice. Changes on the SPAK-NKCC1 complex and tight junction proteins (TJs) in the ChP were quantified by immunofluorescence staining and immunoblotting. Immune cell infiltration in the ChP was assessed by flow cytometry and immunostaining. Cultured ChP epithelium cells (CPECs) and cortical neurons were used to evaluate H2O2-mediated oxidative stress in stimulating the SPAK-NKCC1 complex and cellular damage. In vivo or in vitro pharmacological blockade of the ChP SPAK-NKCC1 cascade with SPAK inhibitor ZT-1a or NKCC1 inhibitor bumetanide were examined. RESULTS: Ischemic stroke stimulated activation of the CPECs apical membrane SPAK-NKCC1 complex, NF-κB, and MMP9, which was associated with loss of the blood-CSF barrier integrity and increased immune cell infiltration into the ChP. Oxidative stress directly activated the SPAK-NKCC1 pathway and resulted in apoptosis, neurodegeneration, and NKCC1-mediated ion influx. Pharmacological blockade of the SPAK-NKCC1 pathway protected the ChP barrier integrity, attenuated ChP immune cell infiltration or neuronal death. CONCLUSION: Stroke-induced pathological stimulation of the SPAK-NKCC1 cascade caused CPECs damage and disruption of TJs at the blood-CSF barrier. The ChP SPAK-NKCC1 complex emerged as a therapeutic target for attenuating ChP dysfunction and lymphocyte invasion after stroke.National Institutes of HealthVeterans AdministrationVA Research Career Scientist awardUPMC Endowed Chair professorship for Brain Disorders Researc

Legal and Ethical Implications of Mobile Live-Streaming Video Apps

The introduction of mobile apps such as Meerkat, Periscope, and Facebook Live has sparked enthusiasm for live-streaming video. This study explores the legal and ethical implications of mobile live-streaming video apps through a review of public-policy considerations and the computing literature as well as analyses of a mix of quantitative and qualitative user data. We identify lines of research inquiry for five policy challenges and two areas of the literature in which the impact of these apps is so far unaddressed. The detailed data gathered from these inquiries will significantly contribute to the design and development of tools, signals or affordances to address the concerns that our study identifies. We hope our work will help shape the fields of ubiquitous computing and collaborative and social computing, jurisprudence, public policy and applied ethics in the future

Hyper-parameter Optimisation by Restrained Stochastic Hill Climbing

Abstract. Machine learning practitioners often refer to hyper-parameter optimisation (HPO) as an art form and a skill that requires intuition and experience; Neuroevolution (NE) typically employs a combination of manual and evolutionary approaches for HPO. This paper explores the integration of a stochastic hill climbing approach for HPO within a NE algorithm. We empirically show that HPO by restrained stochastic hill climbing (HORSHC) is more effective than manual and pure evolutionary HPO. Empirical evidence is derived from a comparison of: (1) a NE algorithm that solely optimises hyper-parameters through evolution and (2) a number of derived algorithms with random search optimisation integration for optimising the hyper-parameters of a Neural Network. Through statistical analysis of the experimental results it has been revealed that random initialisation of hyper-parameters does not significantly affect the final performance of the Neural Networks evolved. However, HORSHC, a novel optimisation approach proposed in this paper has been proven to significantly out-perform the NE control algorithm. HORSHC presents itself as a solution that is computationally comparable in terms of both time and complexity as well as outperforming the control algorithm

Taxonomy based on science is necessary for global conservation

Peer reviewe

Commons/commodity: peer production caught in the Web of the commercial market

The development of digital technology and computer networks has enabled many kinds of online collaboration. This article examines Zimuzu, a Chinese case of online peer production that produces and distributes online Chinese subtitles of foreign media content. Zimuzu provides an opportunity to extend our understanding of how the tensions between the commodity and commons production models are being articulated in an online setting. Using empirical evidence collected from face-to-face interviews, online posts and online ethnographic observation, our analysis demonstrates that there is constant negotiation over which aspects of the two seemingly opposing models will be adopted by the community. We argue that it is important to conceptualize the peer production process as being influenced by power relations within and between the translation groups as well as between the groups and other commercial organizations

Kryobehaelter mit HTSL-Lagerung. Aufbau und Eigenschaften von selbststabilen HTSL-PM Magnetlagern fuer Kryobehaelter

SIGLEAvailable from TIB Hannover: DtF QN1(70,51) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekBundesministerium fuer Bildung, Wissenschaft, Forschung und Technologie, Bonn (Germany)DEGerman

On Being Iterated: The Affective Demands of Design Participation

© 2020 ACM. Iteration is a central feature of most HCI design methods, creating as it does opportunities for engagements with stakeholder groups. But what does iteration demand of those groups? Under what conditions do iterative engagements arise, and with what stakes? Building on experiences with Aboriginal Australian communities, and drawing on feminist and decolonial thinking, we examine the nature of iteration for HCI and how it frames encounters between design and use, with a focus on the affective dimension of engagement in iterative design processes