Walking hand in hand: The role of affection-sharing in understanding the social network effect in same-sex, mixed-sex, and gender-diverse relationships.

Individuals who perceive greater support or approval for their relationships from friends and family also report greater relationship stability and commitment and better mental and physical health (known as the "social network effect"). These associations have been explained, in part, through three cognitive-affective processes: uncertainty reduction, cognitive balance, and dyadic identity formation. However, we know less about cognitive-behavioral mechanisms that might help explain the social network effect. In this study, we propose and test a model in which physical affection-sharing acts as one such behavioral mechanism. In a sample of 1848 individuals in same-sex (n = 696), mixed-sex (n = 1045), and gender-diverse (n = 107) relationships, we found support for our overall model. Our findings suggest that perceived support for one's relationships is a significant predictor of perceived support for physical affection-sharing, which in turn predicts the frequency of affection-sharing in private and public contexts and, ultimately, relationship well-being. However, we also found that relationship type moderates these associations, highlighting how the experience of sharing affection with one's partner changes for many in marginalized relationships, especially in public. We conclude by discussing how our findings contribute to theories of social support for relationships, underscoring the importance of considering affective, cognitive, and behavioral factors relevant to the process. We also emphasize the understudied role of context in shaping affection-sharing experiences across all relationship types.

Short- and long-term memory tasks predict working memory performance, and vice versa.

The Brown-Peterson, operation span, and continual distractor tasks all require people to retain information while performing a distractor task. Scale Independent Memory, Perception, and Learning (SIMPLE), a local relative distinctiveness model, has been fit to aspects of each task and offers the same explanation for each: the distractor task serves to space the items out in time and memory performance depends on the relative distinctiveness of the target item at the time of recall. If this is correct, it follows that performance on all three tasks should correlate, even though the tasks have, at various times, been ascribed to different memory systems, short-term memory, working memory, and long-term memory, respectively. We tested 190 subjects on all three tasks and found that performance on all three tasks is significantly correlated. We then fit the data from each task using SIMPLE. We argue that these results support the relative distinctiveness principle (Surprenant & Neath, 2009). We contrast SIMPLE with other models of the same tasks. (PsycINFO Database Record (c) 2019 APA, all rights reserved).

Dpp/BMP2-4 Mediates Signaling from the D-Quadrant Organizer in a Spiralian Embryo.

In some animal groups, the secondary embryonic axis is patterned by a small group of cells, often called an organizer, that signals to other cells to establish the correct pattern of cell fates. The Dpp/BMP2-4 pathway plays a central role in secondary axis patterning in many animals [1-11], but it has not been examined during early axial patterning in spiralian embryogenesis. This is a deeply conserved mode of development found in mollusks, annelids, nemerteans, entoprocts, and some marine platyhelminth groups (reviewed in [12, 13]). In the spiralian embryo of the mollusk Ilyanassa, we find that the Dpp ortholog (IoDpp) is expressed most strongly on the dorsal side, in cells of the embryonic organizer and its neighbors. Phospho-smad staining indicates that the pathway is active in all lineages during organizer signaling, but activation is strongest on the dorsal side. Knockdown of IoDpp by morpholino oligos prevents the development of all structures that require organizer signaling and ventralizes the embryo. Ectopic activation of the pathway can induce eyes and external shell, which require organizer signaling. These results indicate that Dpp/BMP2-4 signaling is a key part of the spiralian organizer and suggest similarity with other metazoan organizers. However, the fact that IoDpp/BMP2-4 is inducing, rather than repressing, the neuroectoderm is a surprising difference that may be conserved among spiralians. These results connect the spiralian organizer to this general aspect of secondary axis patterning but highlight the significant variation across animals in effects of the pathway on particular cell types and tissues.

Giraffe genome sequence reveals clues to its unique morphology and physiology.

The origins of giraffe's imposing stature and associated cardiovascular adaptations are unknown. Okapi, which lacks these unique features, is giraffe's closest relative and provides a useful comparison, to identify genetic variation underlying giraffe's long neck and cardiovascular system. The genomes of giraffe and okapi were sequenced, and through comparative analyses genes and pathways were identified that exhibit unique genetic changes and likely contribute to giraffe's unique features. Some of these genes are in the HOX, NOTCH and FGF signalling pathways, which regulate both skeletal and cardiovascular development, suggesting that giraffe's stature and cardiovascular adaptations evolved in parallel through changes in a small number of genes. Mitochondrial metabolism and volatile fatty acids transport genes are also evolutionarily diverged in giraffe and may be related to its unusual diet that includes toxic plants. Unexpectedly, substantial evolutionary changes have occurred in giraffe and okapi in double-strand break repair and centrosome functions.