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In this paper I survey a range of trolling behaviors and analyze a particular species that stands out. After a brief discussion of some of the inherent challenges in studying internet speech, I describe a few examples of behaviors commonly described as 'trolling' in order to identify what they have in common. I argue that most of these behaviors already have well-researched offline counterparts. In contrast, in the second half of the paper I argue that so-called 'subcultural trolling' calls out for further analysis: it cannot be fully explained using standard tools like insincerity or bullshit, or even using new tools like dogwhistling. Instead, I propose a new species of speech act force. I conclude by highlighting some implications for broader issues in pragmatics and ethics. [ABSTRACT FROM AUTHOR]

We investigated the effects of two types of competition, races and tournaments (as well as an individual challenge and a do-your-best condition), on two different aspects of performance: effort and strategy. In our experiment, 100 undergraduate participants completed a simple cognitive task under four experimental conditions (in a repeated-measures design) based on different types of competitions and challenges. We used the Linear Ballistic Accumulator to quantify the effects of competition on strategy and effort. The results reveal that competition produced changes in strategy rather than effort, and that trait competitiveness had minimal impact on how people responded to competition. This suggests individuals are more likely to adjust their strategy in competitions, and the uncertainty created by different competition types influences the direction of these strategy adjustments. [ABSTRACT FROM AUTHOR]

We examine the underlying cognitive mechanisms that govern how competitions play out over time. We used cognitive modeling to examine the dynamic effects of time remaining and relative performance (whether the person is winning or losing) on effort and strategy. In this experiment, participants completed a competitive decision-making task with varying time limits and starting scores, in a repeated-measures design. Participants were tasked with scoring more points than their computerized opponent during a certain time frame, gaining and losing points for correct and incorrect decisions, respectively. The results showed that as the competition deadline approached and as participants drew ahead of their opponent within a competition, they increased effort and became more cautious. Furthermore, the effect of relative score on effort and caution changed over the course of a competition as the deadline approached. These results highlight the importance of considering dynamics when working to understand how competitions unfold as well as the underlying cognitive mechanisms that give rise to the dynamic behavior. [ABSTRACT FROM AUTHOR]

Cell–cell signaling in microorganisms is still poorly characterized. In this Methods paper, we describe a genetic procedure for detecting cell-nonautonomous genetic effects, and in particular cell–cell signaling, termed the chimeric colony assay (CCA). The CCA measures the effect of a gene on a biological response in a neighboring cell. This assay can measure cell autonomy for range of biological activities including transcript or protein accumulation, subcellular localization, and cell differentiation. To date, the CCA has been used exclusively to investigate colony patterning in the budding yeast Saccharomyces cerevisiae. To demonstrate the wider potential of the assay, we applied this assay to two other systems: the effect of Grr1 on glucose repression of GAL1 transcription in yeast and the effect of rpsL on stop-codon translational readthrough in Escherichia coli. We also describe variations of the standard CCA that address specific aspects of cell–cell signaling, and we delineate essential controls for this assay. Finally, we discuss complementary approaches to the CCA. Taken together, this Methods paper demonstrates how genetic assays can reveal and explore the roles of cell–cell signaling in microbial processes. [ABSTRACT FROM AUTHOR]

Reports of P. vivax infections among Duffy-negative hosts have accumulated throughout sub-Saharan Africa. Despite this growing body of evidence, no nationally representative epidemiological surveys of P. vivax in sub-Saharan Africa have been performed. To overcome this gap in knowledge, we screened over 17,000 adults in the Democratic Republic of the Congo (DRC) for P. vivax using samples from the 2013-2014 Demographic Health Survey. Overall, we found a 2.97% (95% CI: 2.28%, 3.65%) prevalence of P. vivax infections across the DRC. Infections were associated with few risk-factors and demonstrated a relatively flat distribution of prevalence across space with focal regions of relatively higher prevalence in the north and northeast. Mitochondrial genomes suggested that DRC P. vivax were distinct from circulating non-human ape strains and an ancestral European P. vivax strain, and instead may be part of a separate contemporary clade. Our findings suggest P. vivax is diffusely spread across the DRC at a low prevalence, which may be associated with long-term carriage of low parasitemia, frequent relapses, or a general pool of infections with limited forward propagation. Plasmodium vivax generally accounts for a low proportion of malaria cases in Africa, but population-level data on the distribution of infections is limited. Here, the authors use data from the Democratic Republic of the Congo and show that the prevalence is low (~3%) and diffusely spread. [ABSTRACT FROM AUTHOR]

This article aims to propose a theoretical framework, based on the literature, that supports the growth of students' physical literacy in physical education. The framework features a trained educator who seeks to establish a positive climate for learning based on the creation of a positive culture of movement. It features meaningful student experiences, empowers students and staff, and integrates curriculum. Critical attributes from physical literacy theory are seamlessly integrated and nurtured in all four domains: physical, cognitive, behavioral, and affective. [ABSTRACT FROM AUTHOR]

The Democratic Republic of the Congo (DRC) harbors 11% of global malaria cases, yet little is known about the spatial and genetic structure of the parasite population in that country. We sequence 2537 Plasmodium falciparum infections, including a nationally representative population sample from DRC and samples from surrounding countries, using molecular inversion probes - a high-throughput genotyping tool. We identify an east-west divide in haplotypes known to confer resistance to chloroquine and sulfadoxine-pyrimethamine. Furthermore, we identify highly related parasites over large geographic distances, indicative of gene flow and migration. Our results are consistent with a background of isolation by distance combined with the effects of selection for antimalarial drug resistance. This study provides a high-resolution view of parasite genetic structure across a large country in Africa and provides a baseline to study how implementation programs may impact parasite populations. The genome of the malaria parasite Plasmodium falciparum contains a record of past evolutionary forces. Here, using 2537 parasite sequences from the Democratic Republic of the Congo, the authors demonstrate how drug pressure and human movement have shaped the present-day parasite population. [ABSTRACT FROM AUTHOR]

Ultrafast X-ray imaging on individual fragile specimens such as aerosols [1], metastable particles [2], superfluid quantum systems [3] and live biospecimens [4] provides high-resolution information that is inaccessible with conventional imaging techniques. Coherent X-ray diffractive imaging, however, suffers from intrinsic loss of phase, and therefore structure recovery is often complicated and not always uniquely defined [4], [5]. Here, we introduce the method of in-flight holography, where we use nanoclusters as reference X-ray scatterers to encode relative phase information into diffraction patterns of a virus. The resulting hologram contains an unambiguous three-dimensional map of a virus and two nanoclusters with the highest lateral resolution so far achieved via single shot X-ray holography. Our approach unlocks the benefits of holography for ultrafast X-ray imaging of nanoscale, non-periodic systems and paves the way to direct observation of complex electron dynamics down to the attosecond timescale. Femtosecond X-ray Fourier holography imaging with record-high lateral resolution below 20 nm is demonstrated. Phase information is encoded into the interference of the diffraction patterns of a reference particle with a measurement sample. [ABSTRACT FROM AUTHOR]

The article discusses databases, analysis tools, and other informatics resources related to the use of the Collaborative Cross (CC) and complementary Diversity Outbred (DO) population of mice for analyzing genetic and molecular networks underlying complex traits like mouse behavior. It focuses on computational tools used for genetic mapping and analyzing CC and DO genomes. It also focuses on how these tools help in getting a comprehensive view of the polymorphism segregation in CC and DO mice.

The article discusses the 28th International Mammalian Genome Conference (IMGC) that was held from October 26-29, 2014 in Bar Harbor, Maine. Topics include the bioinformatic workshops, the highlights on mammalian models which are useful in human genetics and research on diseases, and the award to travel scholarships which aims to mentor young scientists. It also mentioned the student satellite symposium held at the auditorium of The Jackson Laboratory.

Background: We aimed to evaluate the clinical robustness of a commercially developed data-driven respiratory gating algorithm based on principal component analysis, for use in routine PET imaging.Methods: One hundred fifty-seven adult FDG PET examinations comprising a total of 1149 acquired bed positions were used for the assessment. These data are representative of FDG scans currently performed at our institution. Data were acquired for 4 min/bed position (3 min/bed for legs). The data-driven gating (DDG) algorithm was applied to each bed position, including those where minimal respiratory motion was expected. The algorithm provided a signal-to-noise measure of respiratory-like frequencies within the data, denoted as R. Qualitative evaluation was performed by visual examination of the waveforms, with each waveform scored on a 3-point scale by two readers and then averaged (score S of 0 = no respiratory signal, 1 = some respiratory-like signal but indeterminate, 2 = acceptable signal considered to be respiratory). Images were reconstructed using quiescent period gating and compared with non-gated images reconstructed with a matched number of coincidences. If present, the SUVmax of a well-defined lesion in the thorax or abdomen was measured and compared between the two reconstructions.Results: There was a strong (r = 0.86) and significant correlation between R and scores S. Eighty-six percent of waveforms with R ≥ 15 were scored as acceptable for respiratory gating. On average, there were 1.2 bed positions per patient examination with R ≥ 15. Waveforms with high R and S were found to originate from bed positions corresponding to the thorax and abdomen: 90% of waveforms with R ≥ 15 had bed centres in the range 5.6 cm superior to 27 cm inferior from the dome of the liver. For regions where respiratory motion was expected to be minimal, R tended to be < 6 and S tended to be 0. The use of DDG significantly increased the SUVmax of focal lesions, by an average of 11% when considering lesions in bed positions with R ≥ 15.Conclusions: The majority of waveforms with high R corresponded to the part of the patient where respiratory motion was expected. The waveforms were deemed suitable for respiratory gating when assessed visually, and when used were found to increase SUVmax in focal lesions. [ABSTRACT FROM AUTHOR]

Apoptosis inhibitor of macrophage (AIM, encoded by cd5l) is a multi-functional circulating protein that has a beneficial role in the regulation of a broad range of diseases, some of which are ameliorated by AIM administration in mice. In blood, AIM is stabilized by association with IgM pentamers and maintains its high circulating levels. The mechanism regulating the excessive accumulation of blood AIM remains unknown, although it is important, since a constitutive increase in AIM levels promotes chronic inflammation. Here we found a physiological AIM-cleavage process that induces destabilization of AIM and its excretion in urine. In blood, IgM-free AIM appeared to be cleaved and reduced in size approximately 10 kDa. Cleaved AIM was unable to bind to IgM and was selectively filtered by the glomerulus, thereby excreted in urine. Amino acid substitution at the cleavage site resulted in no renal excretion of AIM. Interestingly, cleaved AIM retained a comparable potency with full-length AIM in facilitating the clearance of dead cell debris in injured kidney, which is a key response in the recovery of acute kidney injury. Identification of AIM-cleavage and resulting functional modification could be the basis for designing safe and efficient AIM therapy for various diseases. [ABSTRACT FROM AUTHOR]

The ever-increasing brightness of synchrotron radiation sources demands improved X-ray optics to utilise their capability for imaging and probing biological cells, nanodevices, and functional matter on the nanometer scale with chemical sensitivity. Here we demonstrate focusing a hard X-ray beam to an 8 nm focus using a volume zone plate (also referred to as a wedged multilayer Laue lens). This lens was constructed using a new deposition technique that enabled the independent control of the angle and thickness of diffracting layers to microradian and nanometer precision, respectively. This ensured that the Bragg condition is satisfied at each point along the lens, leading to a high numerical aperture that is limited only by its extent. We developed a phase-shifting interferometric method based on ptychography to characterise the lens focus. The precision of the fabrication and characterisation demonstrated here provides the path to efficient X-ray optics for imaging at 1 nm resolution. [ABSTRACT FROM AUTHOR]

A correction to the article “Analyses of allele-specific gene expression in highly divergent mouse crosses identifies pervasive allelic imbalance" that was published online on 2nd March, 2015 after print in the 16th April, 2015 issue is presented.