Response normalization and blur adaptation:data and multi-scale model

Adapting to blurred or sharpened images alters perceived blur of a focused image (M. A. Webster, M. A. Georgeson, & S. M. Webster, 2002). We asked whether blur adaptation results in (a) renormalization of perceived focus or (b) a repulsion aftereffect. Images were checkerboards or 2-D Gaussian noise, whose amplitude spectra had (log-log) slopes from -2 (strongly blurred) to 0 (strongly sharpened). Observers adjusted the spectral slope of a comparison image to match different test slopes after adaptation to blurred or sharpened images. Results did not show repulsion effects but were consistent with some renormalization. Test blur levels at and near a blurred or sharpened adaptation level were matched by more focused slopes (closer to 1/f) but with little or no change in appearance after adaptation to focused (1/f) images. A model of contrast adaptation and blur coding by multiple-scale spatial filters predicts these blur aftereffects and those of Webster et al. (2002). A key proposal is that observers are pre-adapted to natural spectra, and blurred or sharpened spectra induce changes in the state of adaptation. The model illustrates how norms might be encoded and recalibrated in the visual system even when they are represented only implicitly by the distribution of responses across multiple channels

Spatial and seasonal relationships between Pacific harbor seals (Phoca vitulina richardii) and their prey, at multiple scales

Knowing where pinnipeds forage is vital to managing and protecting their populations, and for assessing potential interactions with fisheries. We assessed the spatial relationship between the seasonal distribution of Pacific harbor seals (Phoca vitulina richardii) outfitted with satellite transmitters and the seasonal distributions of potential harbor seal prey species in San Francisco Bay, California. Pearson’s correlation coefficients were calculated between the number of harbor seal locations in an area of the San Francisco Bay and the abundance of specific prey species in the same area. The influence of scale on the analyses was assessed by varying the scale of analysis from 1 to 10 km. There was consistency in the prey species targeted by harbor seals year-round, although there were seasonal differences between the most important prey species. The highest correlations between harbor seals and their prey were found for seasonally abundant benthic species, located within about 10 km of the primary haul-out site. Probable foraging habitat for harbor seals was identified, based on areas with high abundances of prey species that were strongly correlated with harbor seal distribution. With comparable local data inputs, this approach has potential application to pinniped management in other areas, and to decisions about the location of marine reserves designed to protect these species

Identifying the Coping Strategies of Nonoffending Pedophilic and Hebephilic Individuals From Their Online Forum Posts

Individuals who identify as pedophilic or hebephilic, and who do not offend, are increasingly visible in online discourse and as a focus of research. Developing knowledge about this population will offer insights into their psychological needs and, potentially, into the mechanisms and strategies individuals use to live offense-free lives. This study examined coping strategies among members of an online forum supporting pedohebephilic individuals who do not wish to offend. Forum users’ posts were analyzed using thematic analysis. Eleven themes emerged which were classifiable into three superordinate themes around (1) the acceptance of pedophilia, (2) strategies to stay safe, and (3) dealing with sexual arousal. These themes offer insight into the varying strategies used by these individuals to cope with stress and/or to remain offense free. Understanding whether these strategies are adaptive or maladaptive may help develop better support services for those who have not offended and may inform prevention efforts

Extension rates across the northern Shanxi Grabens, China, from Quaternary geology, seismicity and geodesy

Discrepancies between geological, seismic and geodetic rates of strain can indicate that rates of crustal deformation, and hence seismic hazard, are varying through time. Previous studies in the northern Shanxi Grabens, at the northeastern corner of the Ordos Plateau in northern China, have found extension rates of anywhere between 0 and 6 mm a−1 at an azimuth of between 95° and 180°. In this paper we determine extension rates across the northern Shanxi Grabens from offset geomorphological features and a variety of Quaternary dating techniques (including new IRSL and Ar-Ar ages), a Kostrov summation using a 700 yr catalogue of historical earthquakes, and recent campaign GPS measurements. We observe good agreement between Quaternary, seismic and geodetic rates of strain, and we find that the northern Shanxi Grabens are extending at around 1–2 mm a−1 at an azimuth of ≈151°. The azimuth of extension is particularly well constrained and can be reliably inferred from catalogues of small earthquakes. We do not find evidence for any substantial variations in extension rate through time, though there is a notable seismic moment rate deficit since 1750. This deficit could indicate complex fault interactions across large regions, aseismic accommodation of deformation, or that we are quite late in the earthquake cycle with the potential for larger earthquakes in the relatively near future

ELMO1 has an essential role in the internalization of Salmonella Typhimurium into enteric macrophages that impacts disease outcome.

Backgrounds and aims4-6 million people die of enteric infections each year. After invading intestinal epithelial cells, enteric bacteria encounter phagocytes. However, little is known about how phagocytes internalize the bacteria to generate host responses. Previously, we have shown that BAI1 (Brain Angiogenesis Inhibitor 1) binds and internalizes Gram-negative bacteria through an ELMO1 (Engulfment and cell Motility protein 1)/Rac1-dependent mechanism. Here we delineate the role of ELMO1 in host inflammatory responses following enteric infection.MethodsELMO1-depleted murine macrophage cell lines, intestinal macrophages and ELMO1 deficient mice (total or myeloid-cell specific) was infected with Salmonella enterica serovar Typhimurium. The bacterial load, inflammatory cytokines and histopathology was evaluated in the ileum, cecum and spleen. The ELMO1 dependent host cytokines were detected by a cytokine array. ELMO1 mediated Rac1 activity was measured by pulldown assay.ResultsThe cytokine array showed reduced release of pro-inflammatory cytokines, including TNF-α and MCP-1, by ELMO1-depleted macrophages. Inhibition of ELMO1 expression in macrophages decreased Rac1 activation (~6 fold) and reduced internalization of Salmonella. ELMO1-dependent internalization was indispensable for TNF-α and MCP-1. Simultaneous inhibition of ELMO1 and Rac function virtually abrogated TNF-α responses to infection. Further, activation of NF-κB, ERK1/2 and p38 MAP kinases were impaired in ELMO1-depleted cells. Strikingly, bacterial internalization by intestinal macrophages was completely dependent on ELMO1. Salmonella infection of ELMO1-deficient mice resulted in a 90% reduction in bacterial burden and attenuated inflammatory responses in the ileum, spleen and cecum.ConclusionThese findings suggest a novel role for ELMO1 in facilitating intracellular bacterial sensing and the induction of inflammatory responses following infection with Salmonella

Merging enzymes with chemocatalysis for amide bond synthesis

Amides are one of the most fundamental chemical bonds in nature. In addition to proteins and other metabolites, many valuable synthetic products comprise amide bonds. Despite this, there is a need for more sustainable amide synthesis. Herein, we report an integrated next generation multi-catalytic system, merging nitrile hydratase enzymes with a Cu-catalysed N-arylation reaction in a single reaction vessel, for the construction of ubiquitous amide bonds. This synergistic one-pot combination of chemo- and biocatalysis provides an amide bond disconnection to precursors, that are orthogonal to those in classical amide synthesis, obviating the need for protecting groups and delivering amides in a manner unachievable using existing catalytic regimes. Our integrated approach also affords broad scope, very high (molar) substrate loading, and has excellent functional group tolerance, telescoping routes to natural product derivatives, drug molecules, and challenging chiral amides under environmentally friendly conditions at scale

Conditional or unconditional? The effects of implementation intentions on driver behavior

Implementation intentions (IF-THEN plans) exert conditional effects on behavior, meaning that their ability to change behavior is conditional upon encountering the critical situation specified in the IF component of the plan. In the present study, we tested whether implementation intentions can exert unconditional effects on behavior. Consistent with the process of operant generalization, we hypothesized that implementation intentions would change behavior, not only in situations that are contextually identical to those specified in the IF component but also in contextually similar situations. Implementation intentions were not expected to generate behavior-change in contextually different situations to those specified. Participants (N = 139) completed questionnaires measuring speeding behavior and motivation to speed. Experimental participants then specified implementation intentions to avoid speeding in critical situations that were either contextually identical, similar or different to those subsequently encountered on a driving simulator. Control participants received educational information about the risks of speeding. All participants then drove on a driving simulator. Consistent with the hypotheses, participants in both the contextually identical and similar conditions exceeded the speed limit less frequently than did controls. There was no difference in speeding behavior between the contextually different and control conditions. Implications of the findings for behavior-change are discussed

Koinonia

In This IssuePeople are Hungry to Talk About Deep Things (Reprint from The Embarrassed Believer: Reviving Christian Witness in an Age of Unbelief), Hugh Hewitt The Legacy of Ernest L. Boyer, Sr.: The Boyer Center at Messiah College, Debra L. Elliott Filling the Voids in Christian Leadership Training Today: Connecting Student Development, Stewardship & Nonprofit Education with Emerging Leaders, An Interview with Scott Preissler, The Christian Stewardship Association Reply to an Idealistic Job-Searcher, Dana Alexander In The FieldBeyond the Horizon: Student Affairs Practice in the 21st Century, Dennis A. Sheridan Around CampusAnd God Created . . . Sex, Theresa Hannerman and Sarah Marcum Regular FeaturesPresident\u27s Corner Editor\u27s Disk Annual Conference News from the Regions: Spotlight on the Southeast Book Reviews: The Embarrassed Believer: When Hope and Fear Collide Perspective: The Ultimate Student Service: Prayer?https://pillars.taylor.edu/acsd_koinonia/1017/thumbnail.jp

Structural determinants for EB1-mediated recruitment of APC and spectraplakins to the microtubule plus end

EB1 is a member of a conserved protein family that localizes to growing microtubule plus ends. EB1 proteins also recruit cell polarity and signaling molecules to microtubule tips. However, the mechanism by which EB1 recognizes cargo is unknown. Here, we have defined a repeat sequence in adenomatous polyposis coli (APC) that binds to EB1's COOH-terminal domain and identified a similar sequence in members of the microtubule actin cross-linking factor (MACF) family of spectraplakins. We show that MACFs directly bind EB1 and exhibit EB1-dependent plus end tracking in vivo. To understand how EB1 recognizes APC and MACFs, we solved the crystal structure of the EB1 COOH-terminal domain. The structure reveals a novel homodimeric fold comprised of a coiled coil and four-helix bundle motif. Mutational analysis reveals that the cargo binding site for MACFs maps to a cluster of conserved residues at the junction between the coiled coil and four-helix bundle. These results provide a structural understanding of how EB1 binds two regulators of microtubule-based cell polarity

Literature-based reading instruction: Problems, possibilities & polemics in the struggle to change

Concerns are being raised in both professional literature as well as in the popular press regarding certain aspects of the literature-based movement. Here we report on findings from a longitudinal study of a group of first -grade teachers who have been attempting (with varying degrees of success)to introduce literature-based teaching strategies into their classrooms. We inspect the experiences of these teachers in relation to four areas of concern that have been raised regarding literature-based teaching: 1. skills instruction; 2.guided reading strategies; 3. literature selection;and 4. thematic teaching (or curriculum integration). We describe classroom practices and the 9 problems and possibilities associated with teacher change in each of the four areas