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As online news today is an important source of political information and available in vast quantities, understanding its use and its impact on citizens' political knowledge is vital. The aim of the present study is to identify different usage patterns of online news and their relation to individually perceived (i.e., subjective) and actually measurable (i.e., objective) political knowledge. To do so, we conducted an online survey of German online news users (n = 396), investigating characteristics of their online news usage as well as their subjective and objective political knowledge. Latent class analysis revealed six distinct usage patterns, of which a usage pattern drawing heavily on social media and push accesses as a source of news (e.g., Facebook newsfeed, email newsletter) and being rather highly driven by entertainment needs has been found to be associated with an overestimation of one's own political knowledge (illusion of knowing). The potential negative implications of such an illusion of knowing are discussed against the backdrop of the democratic ideal of informed citizens.

Introduction Short-term maternal administration of betamimetics is a common obstetric practice with uses including tocolysis during antenatal corticosteroid administration for fetal lung maturity, intrapartum tachysystole, and prior to external cephalic version. While previous research has demonstrated adverse effects of prolonged use of maternal betamimetics, no prior documentation exists of fetal tachyarrhythmias beyond sinus tachycardia after administration of terbutaline. Case This case documents a transient fetal tachyarrhythmia consistent with presumed atrial flutter after maternal administration of terbutaline for external cephalic version. On day of life 9, the neonate presented in supraventricular tachycardia with signs of heart failure and was subsequently diagnosed with Wolff-Parkinson-White syndrome. Conclusion Maternal administration of terbutaline may be associated with transient fetal tachyarrhythmia. In some fetuses, this cardiac arrhythmia may predate diagnosis of an underlying cardiac disorder, warranting close follow-up after delivery., Highlights • Fetal tachyarrhythmias are possible after maternal terbutaline administration. • Fetal tachyarrhythmias after maternal terbutaline administration may resolve spontaneously. • Terbutaline-induced tachyarrhythmia may precede the diagnosis of an underlying cardiac dysrhythmia.

On social network sites (SNS), people are increasingly confronted with news content—even if they have not actively been looking for it. Although it is widely recognized that SNS have become a main driver for such incidental news exposure, we know little about the factors that influence whether users engage with news encountered on SNS. Thus, this study investigates under which conditions incidental news exposure becomes actual engagement with news by asking how both the perception of the news post and general news usage patterns influence the intention to read news articles encountered on SNS as well as the intention to look for further information about the covered issues. Building on a mobile forced experience sampling study consisting of 840 Facebook news encounters reported from 124 participants, we find that news engagement is mostly determined by participants' perceived interestingness of and prior knowledge about the issue of the news post and to a much lesser degree by social factors unique to SNS (i.e., feelings towards the spreader of the news). In contrast, no influence of content-independent news usage patterns on news engagement could be observed.

The availability of large-scale naturalistic driving data provides enormous opportunities for studying relationships between instantaneous driving decisions prior to involvement in safety critical events (SCEs). This study investigates the role of driving instability prior to involvement in SCEs. While past research has studied crash types and their contributing factors, the role of pre-crash behavior in such events has not been explored as extensively. The research demonstrates how measures and analysis of driving volatility can be leading indicators of crashes and contribute to enhancing safety. Highly detailed microscopic data from naturalistic driving are used to provide the analytic framework to rigorously analyze the behavioral dimensions and driving instability that can lead to different types of SCEs such as roadway departures, rear end collisions, and sideswipes. Modeling results reveal a positive association between volatility and involvement in SCEs. Specifically, increases in both lateral and longitudinal volatilities represented by Bollinger bands and vehicular jerk lead to higher likelihoods of involvement in SCEs. Further, driver behavior related factors such as aggressive driving and lane changing also increases the likelihood of involvement in SCEs. Driver distraction, as represented by the duration of secondary tasks, also increases the risk of SCEs. Likewise, traffic flow parameters play a critical role in safety risk. The risk of involvement in SCEs decreases under free flow traffic conditions and increases under unstable traffic flow. Further, the model shows prediction accuracy of 88.1 % and 85.7 % for training and validation data. These results have implications for proactive safety and providing in-vehicle warnings and alerts to prevent the occurrence of such SCEs.

Microgrids operate in islanding or utility grid mode. In islanding mode, distributed energy sources with power electronics inverters can generate fault currents over a wide range of frequencies. To gain a better understanding of the nature of these events, it is crucial to measure currents at frequencies of up to 20 kHz at transient states with protective relays. Protective relays at these frequency responses should be tested prior to being installed in microgrids. However, testing at high-frequency currents cannot be done with Relay Test Equipment (RTE) that generate signals up to 50th Harmonic for 60 Hz (3 kHz). In this study, a frequency response method and testbed for high-frequency currents of up to 20.16 kHz was developed and tested. The testbed utilized a RTE and High-Frequency Power Source/ Amplifier. Frequency relay experiments were run at frequencies of up to 1 and 20.16 kHz at a current magnitude of 0.1 and 0.5 A, respectively. The events were collected, and the current magnitude and frequency were plotted at time and frequency domain, respectively. The study of current magnitude and frequencies of up to 20.16 kHz for two overcurrent relays was performed and validated the variable frequency testbed and methodology.

Detecting and tracking extreme events in gridded climatological data is a challenging problem on several fronts: algorithms, scalability, and I/O. Successful detection of these events will give climate scientists an alternate view of the behavior of different climatological variables, leading to enhanced scientific understanding of the impacts of events such as heat and cold waves, and on a larger scale, the El Niño Southern Oscillation. Recent advances in computing power and research in data sciences enabled us to look at this problem with a different perspective from what was previously possible. In this paper we present our computationally efficient algorithms for anomalous cluster detection on climate change big data. We provide results on detection and tracking of surface temperature and geopotential height anomalies, a trend analysis, and a study of relationships between the variables. We also identify the limitations of our approaches, future directions for research and alternate approaches.

Passive radiation detection remains one of the most acceptable means of ascertaining the presence of illicit nuclear materials. In maritime applications it is most effective against small to moderately sized vessels, where attenuation in the target vessel is of less concern. Unfortunately, imaging methods that can remove source confusion, localize a source, and avoid other systematic detection issues cannot be easily applied in ship-to-ship inspections because relative motion of the vessels blurs the results over many pixels, significantly reducing system sensitivity. This is particularly true for the smaller watercraft, where passive inspections are most valuable. We have developed a combined gamma-ray, stereo visible-light imaging system that addresses this problem. Data from the stereo imager are used to track the relative location and orientation of the target vessel in the field of view of a coded-aperture gamma-ray imager. Using this information, short-exposure gamma-ray images are projected onto the target vessel using simple tomographic back-projection techniques, revealing the location of any sources within the target. The complex autonomous tracking and image reconstruction system runs in real time on a 48-core workstation that deploys with the system.

The web is going mobile, and the scope of mobile communication is widening tremendously, thus paving the way for a wide array of new forms of mobile device use. However, not every user is necessarily all the time taking advantage of the expanded affordances of mobile devices. Texting and phoning are still the predominant services in mobile communication. Previous research has argued that different styles of mobile communication are related to different user lifestyles. Thus, a remapping and matching of the landscape of mobile communication in relation to user lifestyles seems necessary. In this paper, we take one step back and first consider the instances in which lifestyles become behavior; i.e. actual usage situations of mobile communication. We outline three empirically deduced types of mobile communication usage situations, as well as three types of mobile web usage situations, to shed light on the instant at which lifestyle becomes behavior; i.e. at which specific usage situations of mobile communication actually occur.

The sequence of instantaneous driving decisions and its variations, known as driving volatility, prior to involvement in safety critical events can be a leading indicator of safety. This study focuses on the component of “driving volatility matrix” related to specific normal and safety-critical events, named “event-based volatility.” The research issue is characterizing volatility in instantaneous driving decisions in the longitudinal and lateral directions, and how it varies across drivers involved in normal driving, crash, and/or near-crash events. To explore the issue, a rigorous quasi-experimental study design is adopted to help compare driving behaviors in normal vs unsafe outcomes. Using a unique real-world naturalistic driving database from the 2nd Strategic Highway Research Program (SHRP), a test set of 9593 driving events featuring 2.2 million temporal samples of real-world driving are analyzed. This study features a plethora of kinematic sensors, video, and radar spatiotemporal data about vehicle movement and therefore offers the opportunity to initiate such exploration. By using information related to longitudinal and lateral accelerations and vehicular jerk, 24 different aggregate and segmented measures of driving volatility are proposed that captures variations in extreme instantaneous driving decisions. In doing so, careful attention is given to the issue of intentional vs. unintentional volatility. The volatility indices, as leading indicators of near-crash and crash events, are then linked with safety critical events, crash propensity, and other event specific explanatory variables. Owing to the presence of unobserved heterogeneity and omitted variable bias, fixed- and random-parameter discrete choice models are developed that relate crash propensity to unintentional driving volatility and other factors. Statistically significant evidence is found that driver volatilities in near-crash and crash events are significantly greater than volatility in normal driving events. After controlling for traffic, roadway, and unobserved factors, the results suggest that greater intentional volatility increases the likelihood of both crash and near-crash events. A one-unit increase in intentional volatility is associated with positive vehicular jerk in longitudinal direction increases the chance of crash and near-crash outcome by 15.79 and 12.52 percentage points, respectively. Importantly, intentional volatility in positive vehicular jerk in lateral direction has more negative consequences than intentional volatility in positive vehicular jerk in longitudinal direction. Compared to acceleration/deceleration, vehicular jerk can better characterize the volatility in microscopic instantaneous driving decisions prior to involvement in safety critical events. Finally, the magnitudes of correlations exhibit significant heterogeneity, and that accounting for the heterogeneous effects in the modeling framework can provide more reliable and accurate results. The study demonstrates the value of quasi-experimental study design and big data analytics for understanding extreme driving behaviors in safe vs. unsafe driving outcomes.

Follicular B helper T (Tfh) cells support high affinity and long-term antibody responses. Here we found that within circulating CXCR5(+) CD4(+) T cells in humans and mice, the CCR7(lo)PD-1(hi) subset has a partial Tfh effector phenotype, whereas CCR7(hi) PD-1(lo) cells have a resting phenotype. The circulating CCR7(lo)PD-1(hi) subset was indicative of active Tfh differentiation in lymphoid organs and correlated with clinical indices in autoimmune diseases. Thus the CCR7(lo)PD-1(hi) subset provides a biomarker to monitor protective antibody responses during infection or vaccination and pathogenic antibody responses in autoimmune diseases. Differentiation of both CCR7(hi)PD-1(lo) and CCR7(lo)PD-1(hi) subsets required ICOS and BCL6, but not SAP, suggesting that circulating CXCR5(+) helper T cells are primarily generated before germinal centers. Upon antigen reencounter, CCR7(lo)PD-1(hi) CXCR5(+) precursors rapidly differentiate into mature Tfh cells to promote anti-body responses. Therefore, circulating CCR7(lo)PD-1(hi) CXCR5(+) CD4(+) T cells are generated during active Tfh differentiation and represent a new mechanism of immunological early memory.

Small private vessels are one avenue by which nuclear materials may be smuggled across international borders. While one can contemplate using the terrestrial approach of radiation portal monitors on the navigable waterways that lead to many ports, these systems are ill-suited to the problem. They require vehicles to pass at slow speeds between two closely-spaced radiation sensors, relying on the uniformity of vehicle sizes to space the detectors, and on proximity to link an individual vehicle to its radiation signature. In contrast to roadways where lanes segregate vehicles, and motion is well controlled by inspection booths; channels, inlets, and rivers present chaotic traffic patterns populated by vessels of all sizes. We have developed a unique solution to this problem based on our portal-less portal monitor instrument that is designed to handle free-flowing traffic on roadways with up to five-traffic lanes. The instrument uses a combination of visible-light and gamma-ray imaging to acquire and link radiation images to individual vehicles. It was recently tested in a maritime setting. In this paper we present the instrument, how it functions, and the results of the recent tests.