Cues of Social Status: Associations Between Attractiveness, Dominance, and Status

Hierarchies naturally emerge in social species, and judgments of status in these hierarchies have consequences for social relationships and health. Although judgments of social status are shaped by appearance, the physical cues that inform judgments of status remain unclear. The transition to college presents an opportunity to examine judgments of social status in a newly developing social hierarchy. We examined whether appearances—as measured by raters’ judgments of photographs and videos—provide information about undergraduate students’ social status at their university and in society in Study 1. Exploratory analyses investigated whether associations differed by participants’ sex. Eighty-one first-year undergraduate students ( Mage = 18.20, SD = 0.50; 64.2% female) provided photographs and videos and reported their social status relative to university peers and relative to other people in society. As hypothesized, when participants were judged to be more attractive and dominant they were also judged to have higher status. These associations were replicated in two additional samples of raters who evaluated smiling and neutral photographs from the Chicago Faces Database in Study 2. Multilevel models also revealed that college students with higher self-reported university social status were judged to have higher status, attractiveness, and dominance, although judgments were not related to self-reported society social status. Findings highlight that there is agreement between self-reports of university status and observer-perceptions of status based solely on photographs and videos, and suggest that appearance may shape newly developing social hierarchies, such as those that emerge during the transition to college.

Physical Cues of Matrices Reeducate Nerve Cells

The behavior of nerve cells plays a crucial role in nerve regeneration. The mechanical, topographical, and electrical microenvironment surrounding nerve cells can activate cellular signaling pathways of mechanical transduction to affect the behavior of nerve cells. Recently, biological scaffolds with various physical properties have been developed as extracellular matrix to regulate the behavior conversion of nerve cell, such as neuronal neurite growth and directional differentiation of neural stem cells, providing a robust driving force for nerve regeneration. This review mainly focused on the biological basis of nerve cells in mechanical transduction. In addition, we also highlighted the effect of the physical cues, including stiffness, mechanical tension, two-dimensional terrain, and electrical conductivity, on neurite outgrowth and differentiation of neural stem cells and predicted their potential application in clinical nerve tissue engineering.

Interplay Between Notch and YAP/TAZ Pathways in the Regulation of Cell Fate During Embryo Development

Cells in growing tissues receive both biochemical and physical cues from their microenvironment. Growing evidence has shown that mechanical signals are fundamental regulators of cell behavior. However, how physical properties of the microenvironment are transduced into critical cell behaviors, such as proliferation, progenitor maintenance, or differentiation during development, is still poorly understood. The transcriptional co-activators YAP/TAZ shuttle between the cytoplasm and the nucleus in response to multiple inputs and have emerged as important regulators of tissue growth and regeneration. YAP/TAZ sense and transduce physical cues, such as those from the extracellular matrix or the actomyosin cytoskeleton, to regulate gene expression, thus allowing them to function as gatekeepers of progenitor behavior in several developmental contexts. The Notch pathway is a key signaling pathway that controls binary cell fate decisions through cell–cell communication in a context-dependent manner. Recent reports now suggest that the crosstalk between these two pathways is critical for maintaining the balance between progenitor maintenance and cell differentiation in different tissues. How this crosstalk integrates with morphogenesis and changes in tissue architecture during development is still an open question. Here, we discuss how progenitor cell proliferation, specification, and differentiation are coordinated with morphogenesis to construct a functional organ. We will pay special attention to the interplay between YAP/TAZ and Notch signaling pathways in determining cell fate decisions and discuss whether this represents a general mechanism of regulating cell fate during development. We will focus on research carried out in vertebrate embryos that demonstrate the important roles of mechanical cues in stem cell biology and discuss future challenges.

Zebrafish Primordial Germ Cell Migration

Similar to many other organisms, zebrafish primordial germ cells (PGCs) are specified at a location distinct from that of gonadal somatic cells. Guided by chemotactic cues, PGCs migrate through embryonic tissues toward the region where the gonad develops. In this process, PGCs employ a bleb-driven amoeboid migration mode, characterized by low adhesion and high actomyosin contractility, a strategy used by other migrating cells, such as leukocytes and certain types of cancer cells. The mechanisms underlying the motility and the directed migration of PGCs should be robust to ensure arrival at the target, thereby contributing to the fertility of the organism. These features make PGCs an excellent model for studying guided single-cell migration in vivo. In this review, we present recent findings regarding the establishment and maintenance of cell polarity that are essential for motility and discuss the mechanisms by which cell polarization and directed migration are controlled by chemical and physical cues.

Attractiveness, Trust and Trustworthiness: An Experimental Study

Trust and reciprocating trust are two vital elements in any interpersonal relation. In a situation when there is no reputational information, people have been found to rely on physical cues, such as gender, race, attractiveness, facial expression and others to deduce trustworthiness of other parties. The present paper investigated this stereotype in a trust game by incorporating facial attractiveness. What we were interested in was the impact of attractiveness on trustors’ trust on trustees and trustworthiness of the trustees. The main contribution of the paper is that it investigated the associations using a five-person trust game and allowed the trustors to evaluate the attractiveness of the trustee. The design allowed us to establish the causal association between individuals’ perception on attractiveness and transfer more directly. The results showed male trustors ranked the same female trustees higher than female trustors in terms of attractiveness, and this was translated to higher transferred amount from male trustors to the trustees. Additionally, we find male trustors transferred significantly larger amount to more attractive female trustees than less attractive trustees, but there was no such difference among female trustors. However, the kindness extended by the male trustors to the more attractive female trustees were not reciprocated by the trustees. The trustworthiness as measured by the amount transferred back by trustees was not significantly different between less and more attractive trustees. The results highlighted systematic bias in decision making when prior information about the partners was not available.

Transfer to the clinic: refining forward programming of hPSCs to megakaryocytes for platelet production in bioreactors

The production of in vitro–derived platelets has great potential for transfusion medicine. Here, we build on our experience in the forward programming (FoP) of human pluripotent stem cells (hPSCs) to megakaryocytes (MKs) and address several aspects of the complex challenges to bring this technology to the bedside. We first identify clinical-grade hPSC lines that generate MKs efficiently. We design a bespoke media to maximize both production and maturity of MKs and improve platelet output. Crucially, we transition the lentiviral-based FoP of hPSCs to a nonviral inducible system. We also show how small molecules promote a definitive hematopoiesis phenotype during the differentiation process, thereby increasing the quality of the final product. Finally, we generate platelets using a bioreactor designed to reproduce the physical cues that promote platelet production in the bone marrow. We show that these platelets are able to contribute to both thrombus formation in vitro and have a hemostatic effect in thrombocytopenic mice in vivo.