253 research outputs found
Making Use of Scenarios for Achieving Effective Use in Community Computing Contexts
The concept of effective use is gaining currency as a way of thinking about usability in community informatics. Broadly defined, effective use is the opportunity and capacity of a community group to leverage information communications technologies (ICTs) in order to achieve their goals. Although effective use is a worthy goal, a process for achieving effective use is not clearly defined. This paper combines the concept of scenarios from human-computer interaction (HCI) and participatory design (PD) in order to identify a design process to enhance participation and technological decision making in community information systems design projects. Our process for achieving effective use focuses first on the efficacy of scenarios as a tool to encourage and support participatory design, and second as an anchoring and adjustment heuristic. This study concludes with future research on effective use in community informatics
A Natural Human Retrovirus Efficiently Complements Vectors Based on Murine Leukemia Virus
Background: Murine Leukemia Virus (MLV) is a rodent gammaretrovirus that serves as the backbone for common gene delivery tools designed for experimental and therapeutic applications. Recently, an infectious gammaretrovirus designated XMRV has been identified in prostate cancer patients. The similarity between the MLV and XMRV genomes suggests a possibility that the two viruses may interact when present in the same cell. Methodology/Principal Findings: We tested the ability of XMRV to complement replication-deficient MLV vectors upon coinfection of cultured human cells. We observed that XMRV can facilitate the spread of these vectors from infected to uninfected cells. This functional complementation occurred without any gross rearrangements in the vector structure, and the co-infected cells produced as many as 10 4 infectious vector particles per milliliter of culture medium. Conclusions/Significance: The possibility of encountering a helper virus when delivering MLV-based vectors to human cells in vitro and in vivo needs to be considered to ensure the safety of such procedures
Indications for implant removal after fracture healing: a review of the literature
Introduction: The aim of this review was to collect and summarize published data on the indications for implant removal after fracture healing, since these are not well defined and guidelines hardly exist. Methods: A literature search was performed. Results: Though there are several presumed benefits of implant removal, such as functional improvement and pain relief, the surgical procedure can be very challenging and may lead to complications or even worsening of the complaints. Research has focused on the safety of metal implants (e.g., risk of corrosion, allergy, and carcinogenesis). For these reasons, implants have been removed routinely for decades. Along with the introduction of titanium alloy implants, the need for implant removal became a subject of debate in view of potential (dis)advantages since, in general, implants made of titanium alloys are more difficult to remove. Currently, the main indications for removal from both the upper and lower extremity are mostly 'relative' and patient-driven, such as pain, prominent material, or simply the request for removal. True medical indications like infection or intra-articular material are minor reasons. Conclusion: This review illustrates the great variety of view points in the literature, with large differences in opinions and practices about the indications for implant removal after fracture healing. Since some studies have described asymptomatic patients developing complaints after removal, the general advice nowadays is to remove implants after fracture healing only in symptomatic patients and after a proper informed consent. Well-designed prospective studies on this subject are urgently needed in order to form guidelines based on scientific evidence
BRG1 co-localizes with DNA replication factors and is required for efficient replication fork progression
For DNA replication to occur, chromatin must be remodeled. Yet, we know very little about which proteins alter nucleosome occupancy at origins and replication forks and for what aspects of replication they are required. Here, we demonstrate that the BRG1 catalytic subunit of mammalian SWI/SNF-related complexes co-localizes with origin recognition complexes, GINS complexes, and proliferating cell nuclear antigen at sites of DNA replication on extended chromatin fibers. The specific pattern of BRG1 occupancy suggests it does not participate in origin selection but is involved in the firing of origins and the process of replication elongation. This latter function is confirmed by the fact that Brg1 mutant mouse embryos and RNAi knockdown cells exhibit a 50% reduction in replication fork progression rates, which is associated with decreased cell proliferation. This novel function of BRG1 is consistent with its requirement during embryogenesis and its role as a tumor suppressor to maintain genome stability and prevent cancer
Scenario-based requirements elicitation for user-centric explainable AI
Explainable Artificial Intelligence (XAI) develops technical explanation methods and enable interpretability for human stakeholders on why Artificial Intelligence (AI) and machine learning (ML) models provide certain predictions. However, the trust of those stakeholders into AI models and explanations is still an issue, especially domain experts, who are knowledgeable about their domain but not AI inner workings. Social and user-centric XAI research states it is essential to understand the stakeholder’s requirements to provide explanations tailored to their needs, and enhance their trust in working with AI models. Scenario-based design and requirements elicitation can help bridge the gap between social and operational aspects of a stakeholder early before the adoption of information systems and identify its real problem and practices generating user requirements. Nevertheless, it is still rarely explored the adoption of scenarios in XAI, especially in the domain of fraud detection to supporting experts who are about to work with AI models. We demonstrate the usage of scenario-based requirements elicitation for XAI in a fraud detection context, and develop scenarios derived with experts in banking fraud. We discuss how those scenarios can be adopted to identify user or expert requirements for appropriate explanations in his daily operations and to make decisions on reviewing fraudulent cases in banking. The generalizability of the scenarios for further adoption is validated through a systematic literature review in domains of XAI and visual analytics for fraud detection
Common ground in collaborative intelligence analysis: an empirical study
This paper reports an empirical exploration of how different configurations of collaboration technology affect peoples’ ability to construct and maintain common ground while conducting collaborative intelligence analysis work. Prior studies of collaboration technology have typically focused on simpler conversational tasks, or ones that involve physical manipulation, rather than the complex sensemaking and inference involved in intelligence work. The study explores the effects of video communication and shared visual workspace (SVW) on the negotiation of common ground by distributed teams collaborating in real time on intelligence analysis tasks. The experimental study uses a 2x2 factorial, between-subjects design involving two independent variables: presence or absence of Video and SVW. Two-member teams were randomly assigned to one of the four experimental media conditions and worked to complete several intelligence analysis tasks involving multiple, complex intelligence artefacts. Teams with access to the shared visual workspace could view their teammates’ eWhiteboards. Our results demonstrate a significant effect for the shared visual workspace: the effort of conversational grounding is reduced in the cases where SVW is available. However, there were no main effects for video and no interaction between the two variables. Also, we found that the “conversational grounding effort” required tended to decrease over the course of the tas
Protein kinase C activation disrupts epithelial apical junctions via ROCK-II dependent stimulation of actomyosin contractility
<p>Abstract</p> <p>Background</p> <p>Disruption of epithelial cell-cell adhesions represents an early and important stage in tumor metastasis. This process can be modeled <it>in vitro </it>by exposing cells to chemical tumor promoters, phorbol esters and octylindolactam-V (OI-V), known to activate protein kinase C (PKC). However, molecular events mediating PKC-dependent disruption of epithelial cell-cell contact remain poorly understood. In the present study we investigate mechanisms by which PKC activation induces disassembly of tight junctions (TJs) and adherens junctions (AJs) in a model pancreatic epithelium.</p> <p>Results</p> <p>Exposure of HPAF-II human pancreatic adenocarcinoma cell monolayers to either OI-V or 12-O-tetradecanoylphorbol-13-acetate caused rapid disruption and internalization of AJs and TJs. Activity of classical PKC isoenzymes was responsible for the loss of cell-cell contacts which was accompanied by cell rounding, phosphorylation and relocalization of the F-actin motor nonmuscle myosin (NM) II. The OI-V-induced disruption of AJs and TJs was prevented by either pharmacological inhibition of NM II with blebbistatin or by siRNA-mediated downregulation of NM IIA. Furthermore, AJ/TJ disassembly was attenuated by inhibition of Rho-associated kinase (ROCK) II, but was insensitive to blockage of MLCK, calmodulin, ERK1/2, caspases and RhoA GTPase.</p> <p>Conclusion</p> <p>Our data suggest that stimulation of PKC disrupts epithelial apical junctions via ROCK-II dependent activation of NM II, which increases contractility of perijunctional actin filaments. This mechanism is likely to be important for cancer cell dissociation and tumor metastasis.</p
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