A dynamic charge-charge interaction modulates PP2A:B56 substrate recruitment.

The recruitment of substrates by the ser/thr protein phosphatase 2A (PP2A) is poorly understood, limiting our understanding of PP2A-regulated signaling. Recently, the first PP2A:B56 consensus binding motif, LxxIxE, was identified. However, most validated LxxIxE motifs bind PP2A:B56 with micromolar affinities, suggesting that additional motifs exist to enhance PP2A:B56 binding. Here, we report the requirement of a positively charged motif in a subset of PP2A:B56 interactors, including KIF4A, to facilitate B56 binding via dynamic, electrostatic interactions. Using molecular and cellular experiments, we show that a conserved, negatively charged groove on B56 mediates dynamic binding. We also discovered that this positively charged motif, in addition to facilitating KIF4A dephosphorylation, is essential for condensin I binding, a function distinct and exclusive from PP2A-B56 binding. Together, these results reveal how dynamic, charge-charge interactions fine-tune the interactions mediated by specific motifs, providing a new framework for understanding how PP2A regulation drives cellular signaling

Older and younger adults are influenced differently by dark pattern designs

Considering that prior research has found older users undergo a different privacy decision-making process compared to younger adults, more research is needed to inform the behavioral privacy disclosure effects of these strategies for different age groups. To address this gap, we used an existing dataset of an experiment with a photo-tagging Facebook application. This experiment had a 2x2x5 between-subjects design where the manipulations were common dark pattern design strategies: framing (positive vs. negative), privacy defaults (opt-in vs. opt-out), and justification messages (positive normative, negative normative, positive rationale, negative rationale, none). We compared older (above 65 years old, N=44) and young adults (18 to 25 years old, N=162) privacy concerns and disclosure behaviors (i.e., accepting or refusing automated photo tagging) in the scope of dark pattern design. Overall, we find support for the effectiveness of dark pattern designs in the sense that positive framing and opt-out privacy defaults significantly increased disclosure behavior, while negative justification messages significantly decreased privacy concerns. Regarding older adults, our results show that certain dark patterns do lead to more disclosure than for younger adults, but also to increased privacy concerns for older adults than for younger

Bridging a Bridge: Bringing Two HCI Communities Together

ACM SIGCHI is the largest association for professionals in HCI that bridges computer science, information science, as well as the social and psychological sciences. Meanwhile, a parallel HCI community was formed in 2001 within the Association of Information Systems (AIS SIGHCI) community. While some researchers have already bridged these two HCI subdisciplines, the history and core values of these respective fields are quite different, offering new insights for how we can move forward together to sustain the future of HCI research. The main goal of this workshop is to begin building a bridge between these two communities to maximize the relevance, rigor, and generalizability of HCI research.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/140402/1/wks0159-djamasbi CHI 2018.pdfDescription of wks0159-djamasbi CHI 2018.pdf : Main Fil

Thyroid Disruption by Di-n-Butyl Phthalate (DBP) and Mono-n-Butyl Phthalate (MBP) in Xenopus laevis

BACKGROUND: Di-n-butyl phthalate (DBP), a chemical widely used in many consumer products, is estrogenic and capable of producing seriously reproductive and developmental effects in laboratory animals. However, recent in vitro studies have shown that DBP and mono-n-butyl phthalate (MBP), the major metabolite of DBP, possessed thyroid hormone receptor (TR) antagonist activity. It is therefore important to consider DBP and MBP that may interfere with thyroid hormone system. METHODOLOGY/PRINCIPAL FINDINGS: Nieuwkoop and Faber stage 51 Xenopus laevis were exposed to DBP and MBP (2, 10 or 15 mg/L) separately for 21 days. The two test chemicals decelerated spontaneous metamorphosis in X. laevis at concentrations of 10 and 15 mg/L. Moreover, MBP seemed to possess stronger activity. The effects of DBP and MBP on inducing changes of expression of selected thyroid hormone response genes: thyroid hormone receptor-beta (TRβ), retinoid X receptor gamma (RXRγ), alpha and beta subunits of thyroid-stimulating hormone (TSHα and TSHβ) were detected by qPCR at all concentrations of the compounds. Using mammalian two-hybrid assay in vitro, we found that DBP and MBP enhanced the interactions between co-repressor SMRT (silencing mediator for retinoid and thyroid hormone receptors) and TR in a dose-dependent manner, and MBP displayed more markedly. In addition, MBP at low concentrations (2 and 10 mg/L) caused aberrant methylation of TRβ in head tissue. CONCLUSIONS: The current findings highlight potential disruption of thyroid signalling by DBP and MBP and provide data for human risk assessment

Navigating the Social Terrain with Google Latitude

Although researchers have been building location-based social services for some time now, sharing one???s location has only recently been introduced to the more general population. This paper examines real-world adoption of and resistance to Google Latitude, a social mobile-device application for people to share their locations. We report findings from an analysis of semistructured interviews with 21 participants using grounded theory. Our research reveals how interviewees perceive the social affordances of location-sharing applications to be conceptually intertwined with the conventions of other social networking and communication technologies; Our findings emphasize that many participants felt pressured to not only adopt social applications such as location-sharing, but also to be responsive and accessible at all times. Participants perceived technology-mediated social interactions (such as ???friending??? someone) as highly symbolic, and as problematic if they did not strictly adhere to the established social etiquette. We also found that participants??? perception of the social norms around using Latitude varied widely, affecting how and whether participants used the system

Orientations that Drive Social Media Behavior: Emotional versus Rational Affordances

In this paper, we focus on the social and the material aspects of social media practices that emerge through everyday use of a variety of social media platforms. We draw on the theory of affordances, and through a qualitative study (N=56), we identify two user orientations that operate under different affordances. The emotional orientation leads users to focus on the symbolic meaning behind social media actions and to make emotionally driven decisions about how they use various features. In contrast, a rational orientation is driven by functional considerations. We show how users operating under different orientations lead to conflicts and misunderstandings about the meaning and consequences of using the same material features. We also uncover a connection between orientations, behavior, and age. This work takes an initial step towards understanding and reconciling the conflicts arising from different affordances

Changes in Social Media Behavior During Life Periods of Uncertainty

Social psychology has found that individuals are more self-focused in times of uncertainty such as new life phases. That is, in times of uncertainty and transition, one's thoughts and actions are more egocentric. In other literature, more narcissistic individuals have been shown to behave differently on social media. Bringing these two streams of research together, we investigate whether and how egocentrism during life periods of uncertainty affect social media behaviors. We identify two life phases with patterns of behavior driven by different types of narcissism. The social needs and heightened sense of egocentrism in these different life phases shape social media behavior, albeit in different ways. We discuss the relevance of these motivational and behavioral differences for understanding social media behavior in different phases of life

Don't Disturb My Circles! Boundary Preservation Is at the Center of Location-Sharing Concerns

Past research on location-sharing technologies and social media has uncovered many types of privacy concerns such as informational privacy, impression management and interactional privacy. We interviewed 21 users and nonusers of location-sharing technology and found that many of these privacy concerns are actually just symptoms of a higher-level motivation: the desire to preserve one’s existing offline relationship boundaries. We confirmed and generalized this finding through a nation-wide survey (N=1532) and path analysis. These results imply that designers of location-sharing systems should focus on preserving users’ relationship boundaries to address this cause of privacy concerns

College Student Sampling: Can it Represent Social Media Use by the Work Force?

Research across disciplines examines the dynamics underpinning social behaviors that occur on social media. Sociologists and psychologists analyze social media impact on social life and human relationships. Marketing research focuses on user profiling in order to improve and predict sales. IS research looks at social media for increasing employee performance. These studies make great strides towards understanding networked social behavior. However, like research in many fields, there is a heavy reliance on a non-representative sample population; most empirical studies have been conducted using college students. In this paper, we argue that such sampling does not necessarily reflect the use of social media by employees. This limits the generalizability of past results. Our claims are supported by a large qualitative study contrasting full-time college students with full-time workers in terms of social media use