Historical and contemporary perspectives on the sediments of Lake Rotorua

Lake Rotorua is probably the oldest continuously inundated lake in New Zealand, occupying a caldera formed by or closely associated with the eruption of the Mamaku ignimbrite and the collapse of the Rotorua caldera (Healy, 1975; Lowe and Green, 1991). The lake has undergone drastic changes in size and depth as a result of tectonics, volcanic activity and erosion. Since the Rotoehu eruption, (~60 kyr), the lake level has fluctuated between 120 m above present (280 m asl) and 10 m below present level. The modern lake covers an area of 79 km2 and has a mean depth of 10 m. Despite its long history of sedimentation, Lake Rotorua has an irregular bathymetry with features including faulted blocks, slumps, hydrothermal explosion craters, springs and large methane discharge pock marks

Activation of CD22 a Potential Novel Marker for Ovarian Cancer

4th Annual Lyceum at The University of Texas at Tylerhttps://scholarworks.uttyler.edu/student_posters/1039/thumbnail.jp

Five Facets of Mindfulness and Psychological Health: Evaluating a Psychological Model of the Mechanisms of Mindfulness

There has been an increasing focus on determining the psychological mechanisms underlying the broad effects of mindfulness on psychological health. Mindfulness has been posited to be related to the construct of reperceiving or decentering, defined as a shift in perspective associated with decreased attachment to one\u27s thoughts and emotions. Decentering is proposed to be a meta-mechanism that mobilizes four psychological mechanisms (cognitive flexibility, values clarification, self-regulation, and exposure), which in turn are associated with positive health outcomes. Despite preliminary support for this model, extant studies testing this model have not examined distinct facets of mindfulness. The present study used a multidimensional measure of mindfulness to examine whether this model could account for the associations between five facets of mindfulness and psychological symptoms (depressive symptoms, stress, anxiety symptoms, alcohol-related problems) in a sample of college students (N = 944). Our findings partially support this model. We found significant double-mediated associations in the expected directions for all outcomes (stress, anxiety symptoms, and depressive symptoms) except alcohol-related problems, and for each of the facets of mindfulness except observing. However, decentering and the specific mechanisms did not fully mediate the associations among mindfulness facets and psychological health outcomes. Experimental and ecological momentary assessment designs are needed to understand the psychological processes that account for the beneficial effects of mindfulness

A Brain Unfixed: Unlimited Neurogenesis and Regeneration of the Adult Planarian Nervous System

Powerful genetic tools in classical laboratory models have been fundamental to our understanding of how stem cells give rise to complex neural tissues during embryonic development. In contrast, adult neurogenesis in our model systems, if present, is typically constrained to one or a few zones of the adult brain to produce a limited subset of neurons leading to the dogma that the brain is primarily fixed post-development. The freshwater planarian (flatworm) is an invertebrate model system that challenges this dogma. The planarian possesses a brain containing several thousand neurons with very high rates of cell turnover (homeostasis), which can also be fully regenerated de novo from injury in just 7 days. Both homeostasis and regeneration depend on the activity of a large population of adult stem cells, called neoblasts, throughout the planarian body. Thus, much effort has been put forth to understand how the flatworm can continually give rise to the diversity of cell types found in the adult brain. Here we focus on work using single-cell genomics and functional analyses to unravel the cellular hierarchies from stem cell to neuron. In addition, we will review what is known about how planarians utilize developmental signaling to maintain proper tissue patterning, homeostasis, and cell-type diversity in their brains. Together, planarians are a powerful emerging model system to study the dynamics of adult neurogenesis and regeneration

Mindfulness and Emotional Outcomes: Identifying Subgroups of College Students Using Latent Profile Analysis

In non-meditating samples, distinct facets of mindfulness are found to be negatively correlated, preventing the meaningful creation of a total mindfulness score. The present study used person-centered analyses to distinguish subgroups of college students based on their mindfulness scores, which allows the examination of individuals who are high (or low) on all facets of mindfulness. Using the Lo-Mendell-Rubin Adjusted LRT test, we settled on a 4-class solution that included a high mindfulness group (high on all 5 facets, N = 245), low mindfulness group (moderately low on all 5 facets, N = 563), judgmentally observing group (high on observing, but low on non-judging and acting with awareness, N= 63), and non-judgmentally aware group (low on observing, but high on non-judging and acting with awareness, N= 70). Consistent across all emotional outcomes including depressive symptoms, anxiety symptoms (i.e., worry), affective instability, and distress intolerance, we found that the judgmentally observing group had the most maladaptive emotional outcomes followed by the low mindfulness group. Both the high mindfulness group and the non-judgmentally aware group had the most adaptive emotional outcomes. We discuss the implications of person-centered analyses to exploring mindfulness as it relates to important psychological health outcomes

HOX gene complement and expression in the planarian Schmidtea mediterranea

Abstract Background Freshwater planarians are well known for their regenerative abilities. Less well known is how planarians maintain spatial patterning in long-lived adult animals or how they re-pattern tissues during regeneration. HOX genes are good candidates to regulate planarian spatial patterning, yet the full complement or genomic clustering of planarian HOX genes has not yet been described, primarily because only a few have been detectable by in situ hybridization, and none have given morphological phenotypes when knocked down by RNAi. Results Because the planarian Schmidtea mediterranea (S. mediterranea) is unsegmented, appendage less, and morphologically simple, it has been proposed that it may have a simplified HOX gene complement. Here, we argue against this hypothesis and show that S. mediterranea has a total of 13 HOX genes, which represent homologs to all major axial categories, and can be detected by whole-mount in situ hybridization using a highly sensitive method. In addition, we show that planarian HOX genes do not cluster in the genome, yet 5/13 have retained aspects of axially restricted expression. Finally, we confirm HOX gene axial expression by RNA deep-sequencing 6 anterior–posterior “zones” of the animal, which we provide as a dataset to the community to discover other axially restricted transcripts. Conclusions Freshwater planarians have an unappreciated HOX gene complexity, with all major axial categories represented. However, we conclude based on adult expression patterns that planarians have a derived body plan and their asexual lifestyle may have allowed for large changes in HOX expression from the last common ancestor between arthropods, flatworms, and vertebrates. Using our in situ method and axial zone RNAseq data, it should be possible to further understand the pathways that pattern the anterior–posterior axis of adult planarians

HPA axis reactivity to pharmacologic and psychological stressors in euthymic women with histories of postpartum versus major depression

It is unclear whether women with a history of postpartum depression (PPD) have residual, abnormal hypothalamic-pituitary-adrenal (HPA) axis reactivity, as has been reported in major depression (MDD). Further unclear is whether the abnormalities in HPA axis reactivity associated with MDD represent a stable, underlying predisposition or a state-dependent phenomenon. This study sought the following: (1) to determine if euthymic postpartum women with a history of depression have an abnormal HPA axis reactivity to pharmacologic and psychological challenges and (2) to compare HPA reactivity in women with histories of PPD versus MDD. As a secondary objective, we wanted to determine the influence of trauma history on HPA axis function. Forty-five parous (12–24 months postpartum), euthymic women with history of MDD (n = 15), PPD (n = 15), and controls (n = 15) completed pharmacologic (dexamethasone/corticotropin-releasing hormone (CRH) test [DEX/CRH]) and psychological (Trier social stress test [TSST]) challenges during the luteal phase. Outcome measures were cortisol and adrenocorticotropic hormone (ACTH) response after DEX/CRH, and blood pressure, heart rate, epinephrine, norepinephrine, and cortisol response during the TSST. All groups had robust cortisol and ACTH response to DEX/CRH and cortisol response to TSST. Groups did not differ significantly in cortisol or ACTH response to DEX/CRH or in blood pressure, heart rate, epinephrine, norepinephrine, or cortisol response to TSST. Cortisol/ACTH ratio did not differ significantly between groups. Trauma history was associated with decreased cortisol response to DEX/CRH in women with histories of MDD, which was not significant after correction (F8,125, p = 0.02, Greenhouse-Geisser corrected p = 0.11). Currently euthymic women with histories of MDD or PPD did not demonstrate residual abnormal stress responsivity following administration of either a pharmacologic or psychological stressor