The invisible addiction: Cell-phone activities and addiction among male and female college students

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Human-agent collectives

We live in a world where a host of computer systems, distributed throughout our physical and information environments, are increasingly implicated in our everyday actions. Computer technologies impact all aspects of our lives and our relationship with the digital has fundamentally altered as computers have moved out of the workplace and away from the desktop. Networked computers, tablets, phones and personal devices are now commonplace, as are an increasingly diverse set of digital devices built into the world around us. Data and information is generated at unprecedented speeds and volumes from an increasingly diverse range of sources. It is then combined in unforeseen ways, limited only by human imagination. People’s activities and collaborations are becoming ever more dependent upon and intertwined with this ubiquitous information substrate. As these trends continue apace, it is becoming apparent that many endeavours involve the symbiotic interleaving of humans and computers. Moreover, the emergence of these close-knit partnerships is inducing profound change. Rather than issuing instructions to passive machines that wait until they are asked before doing anything, we will work in tandem with highly inter-connected computational components that act autonomously and intelligently (aka agents). As a consequence, greater attention needs to be given to the balance of control between people and machines. In many situations, humans will be in charge and agents will predominantly act in a supporting role. In other cases, however, the agents will be in control and humans will play the supporting role. We term this emerging class of systems human-agent collectives (HACs) to reflect the close partnership and the flexible social interactions between the humans and the computers. As well as exhibiting increased autonomy, such systems will be inherently open and social. This means the participants will need to continually and flexibly establish and manage a range of social relationships. Thus, depending on the task at hand, different constellations of people, resources, and information will need to come together, operate in a coordinated fashion, and then disband. The openness and presence of many distinct stakeholders means participation will be motivated by a broad range of incentives rather than diktat. This article outlines the key research challenges involved in developing a comprehensive understanding of HACs. To illuminate this agenda, a nascent application in the domain of disaster response is presented

Yielding to Temptation in Buying: Is It Simply a Matter of Self-Control?

Why do consumers yield to temptation? This article looks at two increasingly common types of consumer behavior: impulse buying (IB) and compulsive buying (CB). Specifically, we investigate the impact of self-control (SC), core self-evaluations (CSE), and satisfaction with life (SWL) on these enigmatic consumer behaviors. First, the article develops the distinctions and commonalities between IB and CB. Then, through evaluation of student and general adult samples, the impact of the above three variables on IB and CB is empirically tested. Findings suggest that SC does negatively impact both IB and CB but its relationship with these two behaviors varies across age cohorts. SC was also found to be positively associated with SWL in both samples. CSE was found to positively impact SC and negatively impact both IB and CB. SWL, however, was not found to impact IB or CB. SC also partially mediated the relationship between CSE and IB for adults but not students and partially mediated the impact of CSE (adults only) on CB. As the above results attest, the relationships examined in the present study are nuanced within a given age cohort but also across age cohorts. Future research directions and study implications and limitations are discussed

Effect of core--mantle and tidal torques on Mercury's spin axis orientation

The rotational evolution of Mercury's mantle and its core under conservative and dissipative torques is important for understanding the planet's spin state. Dissipation results from tides and viscous, magnetic and topographic core--mantle interactions. The dissipative core--mantle torques take the system to an equilibrium state wherein both spins are fixed in the frame precessing with the orbit, and in which the mantle and core are differentially rotating. This equilibrium exhibits a mantle spin axis that is offset from the Cassini state by larger amounts for weaker core--mantle coupling for all three dissipative core--mantle coupling mechanisms, and the spin axis of the core is separated farther from that of the mantle, leading to larger differential rotation. The relatively strong core--mantle coupling necessary to bring the mantle spin axis to its observed position close to the Cassini state is not obtained by any of the three dissipative core--mantle coupling mechanisms. For a hydrostatic ellipsoidal core--mantle boundary, pressure coupling dominates the dissipative effects on the mantle and core positions, and dissipation together with pressure coupling brings the mantle spin solidly to the Cassini state. The core spin goes to a position displaced from that of the mantle by about 3.55 arcmin nearly in the plane containing the Cassini state. With the maximum viscosity considered of $\nu\sim 15.0\,{\rm cm^2/s}$ if the coupling is by the circulation through an Ekman boundary layer or $\nu\sim 8.75\times 10^5\,{\rm cm^2/s}$ for purely viscous coupling, the core spin lags the precessing Cassini plane by 23 arcsec, whereas the mantle spin lags by only 0.055 arcsec. Larger, non hydrostatic values of the CMB ellipticity also result in the mantle spin at the Cassini state, but the core spin is moved closer to the mantle spin.Comment: 35 pages, 7 figure

Provenance Network Analytics: An approach to data analytics using data provenance

Provenance network analytics is a novel data analytics approach that helps infer properties of data, such as quality or importance, from their provenance. Instead of analysing application data, which are typically domain-dependent, it analyses the data's provenance as represented using the World Wide Web Consortium's domain-agnostic PROV data model. Specifically, the approach proposes a number of network metrics for provenance data and applies established machine learning techniques over such metrics to build predictive models for some key properties of data. Applying this method to the provenance of real-world data from three different applications, we show that it can successfully identify the owners of provenance documents, assess the quality of crowdsourced data, and identify instructions from chat messages in an alternate-reality game with high levels of accuracy. By so doing, we demonstrate the different ways the proposed provenance network metrics can be used in analysing data, providing the foundation for provenance-based data analytics

Transforming growth factor β is dispensable for the molecular orchestration of Th17 cell differentiation

Interleukin (IL)-17–producing T helper (Th17) cells play a critical role in the pathophysiology of several autoimmune disorders. The differentiation of Th17 cells requires the simultaneous presence of an unusual combination of cytokines: IL-6, a proinflammatory cytokine, and transforming growth factor (TGF) β, an antiinflammatory cytokine. However, the molecular mechanisms by which TGF-β exerts its effects on Th17 cell differentiation remain elusive. We report that TGF-β does not directly promote Th17 cell differentiation but instead acts indirectly by blocking expression of the transcription factors signal transducer and activator of transcription (STAT) 4 and GATA-3, thus preventing Th1 and Th2 cell differentiation. In contrast, TGF-β had no effect on the expression of retinoic acid receptor–related orphan nuclear receptor γt, a Th17-specific transcription factor. Interestingly, in Stat-6−/−T-bet−/− mice, which are unable to generate Th1 and Th2 cells, IL-6 alone was sufficient to induce robust differentiation of Th17 cells, whereas TGF-β had no effect, suggesting that TGF-β is dispensable for Th17 cell development. Consequently, BALB/c Stat-6−/−T-bet−/− mice, but not wild-type BALB/c mice, were highly susceptible to the development of experimental autoimmune encephalomyelitis, which could be blocked by anti–IL-17 antibodies but not by anti–TGF-β antibodies. Collectively, these data provide evidence that TGF-β is not directly required for the molecular orchestration of Th17 cell differentiation

Computational Reconstruction of Multidomain Proteins Using Atomic Force Microscopy Data

SummaryClassical structural biology techniques face a great challenge to determine the structure at the atomic level of large and flexible macromolecules. We present a novel methodology that combines high-resolution AFM topographic images with atomic coordinates of proteins to assemble very large macromolecules or particles. Our method uses a two-step protocol: atomic coordinates of individual domains are docked beneath the molecular surface of the large macromolecule, and then each domain is assembled using a combinatorial search. The protocol was validated on three test cases: a simulated system of antibody structures; and two experimentally based test cases: Tobacco mosaic virus, a rod-shaped virus; and Aquaporin Z, a bacterial membrane protein. We have shown that AFM-intermediate resolution topography and partial surface data are useful constraints for building macromolecular assemblies. The protocol is applicable to multicomponent structures connected in the polypeptide chain or as disjoint molecules. The approach effectively increases the resolution of AFM beyond topographical information down to atomic-detail structures

HAC-ER: a disaster response system based on human-agent collectives

This paper proposes a novel disaster management system called HAC-ER that addresses some of the challenges faced by emergency responders by enabling humans and agents, using state-of-the-art algorithms, to collaboratively plan and carry out tasks in teams referred to as human-agent collectives. In particular, HAC-ER utilises crowdsourcing combined with machine learning to extract situational awareness information from large streams of reports posted by members of the public and trusted organisations. We then show how this information can inform human-agent teams in coordinating multi-UAV deployments as well as task planning for responders on the ground. Finally, HAC-ER incorporates a tool for tracking and analysing the provenance of information shared across the entire system. In summary, this paper describes a prototype system, validated by real-world emergency responders, that combines several state-of-the-art techniques for integrating humans and agents, and illustrates, for the first time, how such an approach can enable more effective disaster response operations

Comment on "Open-ocean fish reveal an omnidirectional solution to camouflage in polarized environments"

Brady et al. (Reports, 20 November 2015, p. 965) claimed that the silvery sides of certain fish are cryptic when viewed by animals with polarization sensitivity, which they termed "polarocrypsis." After examining their evidence, we find this claim to be unsupported due to (i) pseudoreplication, (ii) confounding polarization contrast with intensity contrast, and (iii) measurements taken at very shallow depths

NFIRAOS: TMT's facility adaptive optics system

NFIRAOS, the TMT Observatory's initial facility AO system is a multi-conjugate AO system feeding science light from 0.8 to 2.5 microns wavelength to several near-IR client instruments. NFIRAOS has two deformable mirrors optically conjugated to 0 and 11.2 km, and will correct atmospheric turbulence with 50 per cent sky coverage at the galactic pole. An important requirement is to have very low background: the plan is to cool the optics; and one DM is on a tip/tilt stage to reduce surface count. NFIRAOS' real time control uses multiple sodium laser wavefront sensors and up to three IR natural guide star tip/tilt and/or tip/tilt/focus sensors located within each client instrument. Extremely large telescopes are sensitive to errors due to the variability of the sodium layer. To reduce this sensitivity, NFIRAOS uses innovative algorithms coupled with Truth wavefront sensors to monitor a natural star at low bandwidth. It also includes an IR acquisition camera, and a high speed NGS WFS for operation without lasers. For calibration, NFIRAOS includes simulators of both natural stars at infinity and laser guide stars at varying range distance. Because astrometry is an important science programme for NFIRAOS, there is a precision pinhole mask deployable at the input focal plane. This mask is illuminated by a science wavelength and flat-field calibrator that shines light into NFIRAOS' entrance window. We report on recent effort especially including trade studies to reduce field distortion in the science path and to reduce cost and complexity