Set and element-level compatibility of spatial and location-word stimuli paired to eye-movement, vocal, and keypress response modalities

Set-level and element-level compatibility are two ways to differentiate between different components of stimulus-response compatibility. Element-level compatibility (the difference between incongruent and congruent mappings) has been shown in prior studies to be an increasing function of set-level compatibility (differences between pairings of stimulus and response ensembles). When manual and vocal response sets are paired with spatial (physical location) stimuli and verbal (location-word stimuli), the difference between the incongruent and congruent mappings is larger for the spatial-manual and verbal-vocal conditions than for the alternative pairings of lower set-level compatibility. The common use of eye tracking technology in psychological experiments necessitates investigating the set-level compatibility of the oculomotor system through use of various stimulus sets. Saccadic eye movements are known to yield element-level compatibility effects (longer response times for antisaccades in the opposite direction of the stimulus than for prosaccades in the direction of the stimulus). Although the tendency to make a prosaccade is often described as highly automatic, no attempt has been made to evaluate the overall set-level compatibility of eye-movement responses in comparison to vocal location-naming responses or manual responses. Consequently, I conducted two experiments in which eye-movement responses were compared to those two response modalities: vocal responses (Experiment 1) and keypress responses (Experiment 2). Visual stimuli were varied through use of onsets of squares in left and right spatial locations (spatial codes) or centrally presented words ‘left’ and ‘right’ (verbal codes). The relative set-level compatibility of the two response sets was evaluated by comparing performance with a congruent mapping of spatial and verbal location stimuli; the element-level compatibility effects were evaluated by comparing the differences in performance for incongruent and congruent mappings. The results provide evidence of set-level compatibility differences, with eye movements not only being more compatible than vocal responses with spatial stimuli than verbal stimuli, but also relatively more compatible than keypresses. This result pattern implies that eye movements are more extreme than keypress responses on the spatial end of a response spectrum, compared to vocal responses. Despite this difference in set-level compatibility, in Experiment 1 the element-level mapping effect for sets with high set-level compatibility (including eye-movement responses to spatial) was no larger than that for sets with low set-level compatibility (including eye-movement responses to verbal stimuli). A positive relation between relative set-level compatibility and the element-level mapping effect was found in Experiment 2 when eye movements were compared to keypresses, but this was due mainly to the keypress responses. That incompatible, antisaccade eye-movement responses are not slowed by higher set-level compatibility is counter to the view that set-level compatibility increases activation of the spatially congruent response regardless of the stimulus-response mappings. Alternative possible explanations for the influence of set-level compatibility on eye-movement responses are discussed

Cell-specific and athero-protective roles for RIPK3 in a murine model of atherosclerosis

Receptor-interacting protein kinase 3 (RIPK3) was recently implicated in promoting atherosclerosis progression through a proposed role in macrophage necroptosis. However, RIPK3 has been connected to numerous other cellular pathways, which raises questions about its actual role in atherosclerosis. Furthermore, RIPK3 is expressed in a multitude of cell types, suggesting that it may be physiologically relevant to more than just macrophages in atherosclerosis. In this study

Spontaneous Follicular Exclusion of SHP1-deficient B Cells Is Conditional on the Presence of Competitor Wild-type B Cells

Engagement of antigen receptors on mature B lymphocytes is known to block cell entry into lymphoid follicles and promote accumulation in T cell zones, yet the molecular basis for this change in cell distribution is not understood. Previous studies have shown that follicular exclusion requires a threshold level of antigen receptor engagement combined with occupancy of follicles by B cells without equivalent receptor engagement. The possibility has been raised that follicular composition affects B cell positioning by altering the amount of available antigen and the degree of receptor occupancy. Here we show that follicular composition affects migration of mature B cells under conditions that are independent of antigen receptor occupancy. B cells deficient in the negative regulatory protein tyrosine phosphatase, SHP1, which have elevated intracellular signaling by the B cell receptor, are shown to accumulate in the T zone in the absence of their specific antigen. Follicular exclusion of SHP1–deficient B cells was found to be conditional on the presence of excess B cells that lack elevated intracellular signaling, and was not due to a failure of SHP-1–deficient cells to mature and express the follicle-homing chemokine receptor Burkitt's lymphoma receptor 1. These findings strongly suggest that signals that are negatively regulated by SHP1 promote B cell localization in T cell zones by reducing competitiveness for follicular entry, and provide further evidence that follicular composition influences the positioning of antigen-engaged B cells

Friday Convocation

Program listing performers and works performe

Comprehensive mapping of O-GlcNAc modification sites using a chemically cleavable tag

The post-translational modification of serine or threonine residues of proteins with a single N-acetylglucosamine monosaccharide (O-GlcNAcylation) is essential for cell survival and function. However, relatively few O-GlcNAc modification sites have been mapped due to the difficulty of enriching and detecting O-GlcNAcylated peptides from complex samples. Here we describe an improved approach to quantitatively label and enrich O-GlcNAcylated proteins for site identification. Chemoenzymatic labelling followed by copper(I)-catalysed azide–alkyne cycloaddition (CuAAC) installs a new mass spectrometry (MS)-compatible linker designed for facile purification of O-GlcNAcylated proteins from cell lysates. The linker also allows subsequent quantitative release of O-GlcNAcylated proteins for downstream MS analysis. We validate the approach by unambiguously identifying several established O-GlcNAc sites on the proteins α-crystallin and O-GlcNAc transferase (OGT), as well as discovering new, previously unreported sites on OGT. Notably, these novel sites on OGT lie in key functional domains of the protein, underscoring how this site identification method may reveal important biological insights into protein activity and regulation

Porewater Carbonate Chemistry Dynamics in a Temperate and a Subtropical Seagrass System

Seagrass systems are integral components of both local and global carbon cycles and can substantially modify seawater biogeochemistry, which has ecological ramifications. However, the influence of seagrass on porewater biogeochemistry has not been fully described, and the exact role of this marine macrophyte and associated microbial communities in the modification of porewater chemistry remains equivocal. In the present study, carbonate chemistry in the water column and porewater was investigated over diel timescales in contrasting, tidally influenced seagrass systems in Southern California and Bermuda, including vegetated (Zostera marina) and unvegetated biomes (0–16 cm) in Mission Bay, San Diego, USA and a vegetated system (Thallasia testudinium) in Mangrove Bay, Ferry Reach, Bermuda. In Mission Bay, dissolved inorganic carbon (DIC) and total alkalinity (TA) exhibited strong increasing gradients with sediment depth. Vertical porewater profiles differed between the sites, with almost twice as high concentrations of DIC and TA observed in the vegetated compared to the unvegetated sediments. In Mangrove Bay, both the range and vertical profiles of porewater carbonate parameters such as DIC and TA were much lower and, in contrast to Mission Bay where no distinct temporal signal was observed, biogeochemical parameters followed the semi-diurnal tidal signal in the water column. The observed differences between the study sites most likely reflect a differential influence of biological (biomass, detritus and infauna) and physical processes (e.g., sediment permeability, residence time and mixing) on porewater carbonate chemistry in the different settings

Program Development and Implementation for South Carolina Youth through Expanded Food and Nutrition Education Program (EFNEP)

The Expanded Food Nutrition and Education Program (EFNEP) is a federally-funded program that aims at informing and educating limited-resource children, youth, and families in developing and maintaining a nutritionally sound diet, and a physically active lifestyle. Many of the intervention programs implemented through Youth EFNEP are created to be part of an existing school curriculum or as an after-school program. Currently, few programs exist that allow for easy transferability of these already existing curriculums to a summer camp setting.Therefore, the purpose of our Creative Inquiry was to develop the students\u27 abilities to design and implement a Nutrition Education program for youth audiences in a community setting. Students\u27 responsibilities comprised the analysis of lesson structure for grades K-12, development of lesson materials, implementation of the nutrition education lessons with youth audiences from surrounding community areas, and the application of Youth EFNEP evaluation tools.The 8-lesson curriculum is being pilot-tested during the fall of 2014 and spring of 2015 at Littlejohn Community Center in Clemson. The students have taken a leading role in the implementation of the nutrition education activities at the center, acquired the skills to work with low income audiences and have been actively providing the necessary feedback to improve the quality and content of the curriculum, so that one day it becomes a tool that can be used nationwide in summer camps by Youth EFNEP educators

Proinflammatory mediators, TNFα, IFNγ, and thrombin, directly induce lymphatic capillary tube regression

In this work, we sought to investigate the direct effects of proinflammatory mediators on lymphatic endothelial cell (LEC) capillaries and whether they might induce regression. Our laboratory has developed novel in-vitro, serum-free, lymphatic tubulogenesis assay models whereby human LEC tube networks readily form in either three-dimensional collagen or fibrin matrices. These systems were initially conceptualized in the hopes of better understanding the influence of proinflammatory mediators on LEC capillaries. In this work, we have screened and identified proinflammatory mediators that cause regression of LEC tube networks, the most potent of which is TNFα (tumor necrosis factor alpha), followed by IFNγ (interferon gamma) and thrombin. When these mediators were combined, even greater and more rapid lymphatic capillary regression occurred. Surprisingly, IL-1β (interleukin-1 beta), one of the most potent and pathologic cytokines known, had no regressive effect on these tube networks. Finally, we identified new pharmacological drug combinations capable of rescuing LEC capillaries from regression in response to the potent combination of TNFα, IFNγ, and thrombin. We speculate that protecting lymphatic capillaries from regression may be an important step toward mitigating a wide variety of acute and chronic disease states, as lymphatics are believed to clear both proinflammatory cells and mediators from inflamed and damaged tissue beds. Overall, these studies identify key proinflammatory mediators, including TNFα, IFNγ, and thrombin, that induce regression of LEC tube networks, as well as identify potential therapeutic agents to diminish LEC capillary regression responses

Objective burden, resources, and other stressors among informal cancer caregivers: a hidden quality issue?

A great deal of clinical cancer care is delivered in the home by informal caregivers (e.g. family, friends), who are often untrained. Caregivers' context varies widely, with many providing care despite low levels of resources and high levels of additional demands