Understanding death as the cessation of intentional action: A cross-cultural developmental study

Determining whether or not an entity is capable of acting intentionally is a fundamental cognitive skill that emerges in the first year of infancy, and the inability to act is a key aspect distinguishing dead from living things. Though young children’s understanding of death is generally thought to be poor, an understanding of death as the permanent cessation of agency might develop early in childhood. This study tested the cessation-of-agency hypothesis cross-culturally, by examining the differences between children’s judgments about sleeping and dead animals. The results showed that children understand that death entails the permanent cessation of the ability to act by age 4 in two different cultures. This is consistent with a view that those distinctions that are most crucial for adaptive decision-making are the ones that develop earliest

Youth Speaks Up: Perceived Communication Changes Experienced by Grade 6 Participants in a Personal Development Program

A nine-month program entitled Youth Speaks Up is delivered annually to grade 6 students from Sydney, Nova Scotia. One goal of the program is to provide an opportunity for the development of positive communication skills in participants. The purpose of this project was to determine if students participating in the program perceived changes in their communication ability and comfort level as a result of participation in the program. Qualitative focus groups were conducted, and responses suggest that many participants experienced positive changes in their communication comfort levels in public and interpersonal communication contexts, and specifically in their ability and willingness to express their ideas. Participants believed factors such as consistent practice and interaction with new people influenced the changes. Students’ recommendations for program development are also presented.À chaque année, les élèves de la 6e année à Sydney, en Nouvelle-Écosse, participent à un programme d’une durée de neuf mois intitulé Youth Speaks Up (La parole aux jeunes). Le programme vise, entre autres, le développement d’aptitudes en communication positives chez les participants. L’objectif de cette étude était de déterminer si les participants croyaient que le programme avait entraîné des changements dans leurs aptitudes en communication et leur sentiment de bien-être. Les conclusions tirées à partir de sessions qualitatives avec des groupes de discussion indiquent que plusieurs participants constataient des changements positifs dans le sentiment de bien-être qu’ils ressentaient dans des contextes de communication interpersonnelle et en public, plus précisément dans leur habileté et leur volonté d’exprimer leurs idées. Les participants étaient d’avis que ces changements étaient en partie attribuables à des facteurs tels la pratique régulière et l’interaction avec de nouvelles personnes. Nous présentons également les recommandations qu’ont faites les élèves pour le développement du programme

We’re Here, You Just Don’t Know How to Reach Us: Conducting Research with Citizens on the Socio-Economic Margins

In this paper, methodological challenges that emerged when conducting research with socially and economically disadvantaged young adults in a semi-rural community are examined. Recruitment and retention issues related to ethics protocols, trust, and economic disadvantage are addressed. Strategies governing bodies can employ to support research with difficult to reach populations are suggested

Communication Lab Peer Facilitators: What\u27s in It for Them?

Peer tutors have been used extensively within the communication discipline to enhance students\u27 learning experiences (Hill, 1981; Webb & Lane, 1986). Research suggests that peer tutoring can have positive rewards for tutors and tutees (Goodland & Hurst, 1989; Topping, 1996). However, there is little to no research that explores the benefits received by peer tutors who run small group communication lab sessions for basic communication course students. The qualitative data from focus group indicate that peer facilitators experienced: 1) self-development in terms of their self-esteem, confidence, and respect from themselves and others; 2) improved public speaking skills and better interpersonal relationship with family and friends, other peer facilitators, and individuals in positions of authority; and 3) external rewards in that they felt better prepared for post baccalaureate programs and to compete in the workplace. The results of this study may be used as a basis for more in-depth research on the benefits derived from the peer facilitation experience in the basic communication course

Platelet endothelial cell adhesion molecule-1 inhibits platelet response to thrombin and von Willebrand factor by regulating the internalization of glycoprotein Ib via AKT/glycogen synthase kinase-3/dynamin and integrin αIIbβ3

OBJECTIVE: Platelet endothelial cell adhesion molecule-1 (PECAM-1) regulates platelet response to multiple agonists. How this immunoreceptor tyrosine-based inhibitory motif-containing receptor inhibits G protein-coupled receptor-mediated thrombin-induced activation of platelets is unknown. APPROACH AND RESULTS: Here, we show that the activation of PECAM-1 inhibits fibrinogen binding to integrin αIIbβ3 and P-selectin surface expression in response to thrombin (0.1-3 U/mL) but not thrombin receptor-activating peptides SFLLRN (3×10(-7)-1×10(-5) mol/L) and GYPGQV (3×10(-6)-1×10(-4) mol/L). We hypothesized a role for PECAM-1 in reducing the tethering of thrombin to glycoprotein Ibα (GPIbα) on the platelet surface. We show that PECAM-1 signaling regulates the binding of fluorescein isothiocyanate-labeled thrombin to the platelet surface and reduces the levels of cell surface GPIbα by promoting its internalization, while concomitantly reducing the binding of platelets to von Willebrand factor under flow in vitro. PECAM-1-mediated internalization of GPIbα was reduced in the presence of both EGTA and cytochalasin D or latrunculin, but not either individually, and was reduced in mice in which tyrosines 747 and 759 of the cytoplasmic tail of β3 integrin were mutated to phenylalanine. Furthermore, PECAM-1 cross-linking led to a significant reduction in the phosphorylation of glycogen synthase kinase-3β Ser(9), but interestingly an increase in glycogen synthase kinase-3α pSer(21). PECAM-1-mediated internalization of GPIbα was reduced by inhibitors of dynamin (Dynasore) and glycogen synthase kinase-3 (CHIR99021), an effect that was enhanced in the presence of EGTA. CONCLUSIONS: PECAM-1 mediates internalization of GPIbα in platelets through dual AKT/protein kinase B/glycogen synthase kinase-3/dynamin-dependent and αIIbβ3-dependent mechanisms. These findings expand our understanding of how PECAM-1 regulates nonimmunoreceptor signaling pathways and helps to explains how PECAM-1 regulates thrombosis

Platelet endothelial cell adhesion molecule-1 regulates collagen-stimulated platelet function by modulating the association of phosphatidylinositol 3-kinase with Grb-2-associated binding protein-1 and linker for activation of T cells

Background: Platelet activation by collagen depends on signals transduced by the glycoprotein (GP)VI–Fc receptor (FcR)-chain collagen receptor complex, which involves recruitment of phosphatidylinositol 3-kinase (PI3K) to phosphorylated tyrosines in the linker for activation of T cells (LAT). An interaction between the p85 regulatory subunit of PI3K and the scaffolding molecule Grb-2-associated binding protein-1 (Gab1), which is regulated by binding of the Src homology 2 domain-containing protein tyrosine phosphatase-2 (SHP-2) to Gab1, has been shown in other cell types to sustain PI3K activity to elicit cellular responses. Platelet endothelial cell adhesion molecule-1 (PECAM-1) functions as a negative regulator of platelet reactivity and thrombosis, at least in part by inhibiting GPVI–FcR-chain signaling via recruitment of SHP-2 to phosphorylated immunoreceptor tyrosine-based inhibitory motifs in PECAM-1. Objective: To investigate the possibility that PECAM-1 regulates the formation of the Gab1–p85 signaling complexes, and the potential effect of such interactions on GPVI-mediated platelet activation in platelets. Methods: The ability of PECAM-1 signaling to modulate the LAT signalosome was investigated with immunoblotting assays on human platelets and knockout mouse platelets. Results: PECAM-1-associated SHP-2 in collagen-stimulated platelets binds to p85, which results in diminished levels of association with both Gab1 and LAT and reduced collagen-stimulated PI3K signaling. We therefore propose that PECAM-1-mediated inhibition of GPVI-dependent platelet responses result, at least in part, from recruitment of SHP-2–p85 complexes to tyrosine-phosphorylated PECAM-1, which diminishes the association of PI3K with activatory signaling molecules, such as Gab1 and LAT

NCBI GEO: mining millions of expression profiles—database and tools

The Gene Expression Omnibus (GEO) at the National Center for Biotechnology Information (NCBI) is the largest fully public repository for high-throughput molecular abundance data, primarily gene expression data. The database has a flexible and open design that allows the submission, storage and retrieval of many data types. These data include microarray-based experiments measuring the abundance of mRNA, genomic DNA and protein molecules, as well as non-array-based technologies such as serial analysis of gene expression (SAGE) and mass spectrometry proteomic technology. GEO currently holds over 30 000 submissions representing approximately half a billion individual molecular abundance measurements, for over 100 organisms. Here, we describe recent database developments that facilitate effective mining and visualization of these data. Features are provided to examine data from both experiment- and gene-centric perspectives using user-friendly Web-based interfaces accessible to those without computational or microarray-related analytical expertise. The GEO database is publicly accessible through the World Wide Web at http://www.ncbi.nlm.nih.gov/geo

Coping with environmental eukaryotes; identification of pseudomonas syringae genes during the interaction with alternative hosts or predators

Understanding the molecular mechanisms underpinning the ecological success of plant pathogens is critical to develop strategies for controlling diseases and protecting crops. Recent observations have shown that plant pathogenic bacteria, particularly Pseudomonas, exist in a range of natural environments away from their natural plant host e.g., water courses, soil, non-host plants. This exposes them to a variety of eukaryotic predators such as nematodes, insects and amoebae present in the environment. Nematodes and amoeba in particular are bacterial predators while insect herbivores may act as indirect predators, ingesting bacteria on plant tissue. We therefore postulated that bacteria are probably under selective pressure to avoid or survive predation and have therefore developed appropriate coping mechanisms. We tested the hypothesis that plant pathogenic Pseudomonas syringae are able to cope with predation pressure and found that three pathovars show weak, but significant resistance or toxicity. To identify the gene systems that contribute to resistance or toxicity we applied a heterologous screening technique, called Rapid Virulence Annotation (RVA), for anti-predation and toxicity mechanisms. Three cosmid libraries for P. syringae pv. aesculi, pv. tomato and pv. phaseolicola, of approximately 2000 cosmids each, were screened in the susceptible/non-toxic bacterium Escherichia coli against nematode, amoebae and an insect. A number of potential conserved and unique genes were identified which included genes encoding haemolysins, biofilm formation, motility and adhesion. These data provide the first multi-pathovar comparative insight to how plant pathogens cope with different predation pressures and infection of an insect gut and provide a foundation for further study into the function of selected genes and their role in ecological success

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