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Stress generation posits that (a) individuals at-risk for psychopathology may inadvertently experience higher rates of prospective dependent stress (i.e., stressors that are in part influenced by their thoughts and behaviors) but not independent stress (i.e., stressors occurring outside their influence), and (b) this elevated dependent stress, in some measure, is what places these individuals at-risk for future psychopathology. In recognition of 30 years of stress generation research, we conducted a systematic review and meta-analysis using frequentist and Bayesian approaches (102 articles with 104 eligible studies, N = 31,541). Generally strong support was found for psychopathology predicting dependent stress (e.g., ds Overall psychopathology = 0.36-0.52, BF₁₀ = 946.00 to 4.65 × 10¹⁸). Moderator analyses for dependent stress revealed larger effects for briefer assessments periods, shorter follow-ups, and self-report measures than for interviews. Among risk factors, depressogenic cognitive styles (ds = .26-.50, BF₁₀ = 47.50 to 1.00 × 10⁵) and general interpersonal vulnerability (ds = .26-.44, BF₁₀ = 2.72 to 2708.00) received the strongest support as stress generation mechanisms, and current evidence is modest for protective factors predicting dependent stress. Overall, larger effects were generally found for prospective prediction of dependent stress than independent stress. Evaluations of mediation in the research literature were relatively few, limiting the current review to qualitative analysis of the mediation component of stress generation. General support was found, however, for dependent stress as a mediator for psychopathology and associated risk factors in relation to subsequent psychopathology. The current review ends with recommendations for future research and integration of stress generation within minority stress frameworks. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Social media (SM) is widely used among adolescents, making the relationship between SM and affect in this population important to understand. However, previous research has largely used methods that do not capture the dynamic and variable nature of SM or measure the consistency of effects across global affect and specific emotions. The current study examined the momentary relationship between positive and negative SM experiences and global positive affect (PA) and negative affect (NA), as well as specific affective states of PA and NA. Adolescents ( N  = 62; 14-17 years old) were recruited from SM platforms to participate in an eight-week ecological momentary assessment study. Participants reported three times per day on PA and NA and positive and negative SM experiences. Random intercept and random slope models were used to examine within-person associations between momentary positive and negative SM experiences and affect after controlling for between-person differences. At prompts when participants reported greater-than-usual positive SM experiences, they reported higher global PA and lower global NA. At prompts when participants reported greater than their average negative SM experiences, they endorsed lower global PA and higher global NA. These results were consistent across same-valence specific affective states. The current study highlights proximal associations between SM experiences and affect, highlighting potential avenues of short-term risk and protection., Supplementary Information: The online version contains supplementary material available at 10.1007/s42761-024-00257-x., Competing Interests: Conflicts of InterestNot applicable., (© The Author(s) 2024.)

Objective: Eating disorder (ED) behaviors are often characterized as indirect forms of self-harm. However, recent research has found less clear demarcations between direct self-harming behaviors (e.g., nonsuicidal self-injury [NSSI], suicidal behaviors) than previously assumed. The aim of this study was to replicate findings of this prior research on adult populations in adolescents with a history of restrictive eating., Method: A total of 117 adolescents between ages 12-14 were included in the study. Participants reported the presence and frequency of binge eating, compensatory, restrictive eating, and NSSI. Participants also reported thoughts of and intentions to hurt and kill themselves when engaging in each behavior on average. The t-tests and linear effects models were conducted to compare self-harming thoughts and intentions across behaviors., Results: Participants reported at least some intent to hurt themselves physically in the moment and in the long-term when engaging in all ED behaviors and NSSI, and reported engaging in these behaviors while thinking about suicide. Direct self-harming knowledge and intentions were most frequently reported with NSSI and longer-term knowledge and intentions via NSSI and restrictive eating. Additionally, participants reported some suicidal thoughts and intentions across behaviors., Discussion: This study replicates prior research, suggesting that adolescents engage in ED behaviors and NSSI with non-zero self-harming and suicidal thoughts and intentions. ED behaviors and NSSI may better be explained on a continuum. Implications include the recommendation of safety planning during ED treatment., Public Significance Statement: This study highlights the overlap between eating disorder (ED) behaviors, nonsuicidal self-injury (NSSI), and suicide. Though clear distinctions typically exist for motives of self-harming behavior between ED behaviors (i.e., indirect, in the long run) and NSSI (i.e., direct, in the moment), this research suggests that intentions for self-harming and suicide may exist on a continuum. Clinical ED treatment should consider safety planning as part of routine interventions., (© 2023 Wiley Periodicals LLC.)

Microbial communities and their associated metabolic activity in marine sediments have a profound impact on global biogeochemical cycles. Their composition and structure are attributed to geochemical and physical factors, but finding direct correlations has remained a challenge. Here we show a significant statistical relationship between variation in geochemical composition and prokaryotic community structure within deep-sea sediments. We obtained comprehensive geochemical data from two gravity cores near the hydrothermal vent field Loki's Castle at the Arctic Mid-Ocean Ridge, in the Norwegian-Greenland Sea. Geochemical properties in the rift valley sediments exhibited strong centimeter-scale stratigraphic variability. Microbial populations were profiled by pyrosequencing from 15 sediment horizons (59,364 16S rRNA gene tags), quantitatively assessed by qPCR, and phylogenetically analyzed. Although the same taxa were generally present in all samples, their relative abundances varied substantially among horizons and fluctuated between Bacteria- and Archaea-dominated communities. By independently summarizing covariance structures of the relative abundance data and geochemical data, using principal components analysis, we found a significant correlation between changes in geochemical composition and changes in community structure. Differences in organic carbon and mineralogy shaped the relative abundance of microbial taxa. We used correlations to build hypotheses about energy metabolisms, particularly of the Deep Sea Archaeal Group, specific Deltaproteobacteria, and sediment lineages of potentially anaerobic Marine Group I Archaea. We demonstrate that total prokaryotic community structure can be directly correlated to geochemistry within these sediments, thus enhancing our understanding of biogeochemical cycling and our ability to predict metabolisms of uncultured microbes in deep-sea sediments.

The thermal springs Trollosen and Fisosen, located on the High Arctic archipelago Svalbard, discharge saline groundwaters rich in hydrogen sulfide and ammonium through a thick layer of permafrost. Large amounts of biomass that consist of filamentous microorganisms containing sulfur granules, as analyzed with energy dispersive X-ray analysis, were found in the outflow. Prokaryotic 16S rRNA gene libraries and quantitative polymerase chain reaction (qPCR) analyses reported bacteria of the γ- and ɛ-proteobacterial classes as the dominant organisms in the filaments and the planktonic fractions, closely related to known chemolithoautotrophic sulfur oxidizers (Thiotrix and Sulfurovum). Archaea comprised ∼1% of the microbial community, with the majority of sequences affiliated with the Thaumarchaeota. Archaeal and bacterial genes coding for a subunit of the enzyme ammonia monooxygenase (amoA) were detected, as well as 16S rRNA genes of Nitrospira, all of which is indicative of potential complete nitrification in both springs. 16S rRNA sequences related to methanogens and methanotrophs were detected as well. This study provides evidence that the microbial communities in Trollosen and Fisosen are sustained by chemolithotrophy, mainly through the oxidation of reduced sulfur compounds, and that ammonium and methane might be minor, additional sources of energy and carbon.

Lichens are common as colonizers of bare rocks and contribute to weathering, but their associated bacterial communities have been poorly studied. In this study Hydropunctaria maura, Ophioparma ventosa, Pertusaria corallina and Rhizocarpon geographicum were analysed to determine the influence of lichens on lichen-rock-associated microbial metacommunities. For the first time, Archaea were documented to be associated with rock-inhabiting lichens. All the archaeal sequences obtained were affiliated with Crenarchaeota. The Bacteria detected in the lichen-rock samples were affiliated with the major lineages Acidobacteria, Actinobacteria, Alpha-, Beta-, Gammaproteobacteria, Bacteriodetes, Chloroflexi, Deinococcus, Firmicutes, Planctomycetes, Tenericutes and Cyanobacteria. The microbial communities of O. ventosa, P. corallina and R. geographicum were more similar to each other both terms of the number and types of different sequences, than to H. maura. A higher bacterial diversity was observed endolithically than within the epilithic lichen thalli directly above. The abundance of Archaea were also generally higher endolithically than in the epilithic lichen thalli, while the abundance of Bacteria was higher in the lichen thalli compared with within the rock. These results demonstrated that the lichen-rock interfaces are complex habitats, where the macroscopic lichens influence the composition of microbial metacommunities., (© 2010 Society for Applied Microbiology and Blackwell Publishing Ltd.)

The Arctic Mid-Ocean Ridge (AMOR) represents one of the most slow-spreading ridge systems on Earth. Previous attempts to locate hydrothermal vent fields and unravel the nature of venting, as well as the provenance of vent fauna at this northern and insular termination of the global ridge system, have been unsuccessful. Here, we report the first discovery of a black smoker vent field at the AMOR. The field is located on the crest of an axial volcanic ridge (AVR) and is associated with an unusually large hydrothermal deposit, which documents that extensive venting and long-lived hydrothermal systems exist at ultraslow-spreading ridges, despite their strongly reduced volcanic activity. The vent field hosts a distinct vent fauna that differs from the fauna to the south along the Mid-Atlantic Ridge. The novel vent fauna seems to have developed by local specialization and by migration of fauna from cold seeps and the Pacific.

Korarchaeota constitute a recently proposed and little characterized kingdom of Archaea that might have diverged before the lineages of Crenarchaeota and Euryarchaeota split. To assess the diversity, distribution and abundance of Korarchaeota, we analysed 19 terrestrial hot springs in Hveragerdi and Krysuvik, Iceland, and in Kamchatka, Russia. The springs were 70-97 degrees C with pH 2.5-6.5. Out of 19 springs, 12 tested positive for Korarchaeota with specific primers. A Korarchaeota 16S rDNA library was made from each of these. From the 301 clones sequenced, 87 unique sequences were obtained from Iceland and 33 from Kamchatka. The similarity between Kamchatkan and Icelandic 16S rDNA sequences and that of Candidatus Korarchaeum cryptofilum was

The effect of diazepam and specific ligands of peripheral-type benzodiazepine receptors (PBRs) on growth factor-induced DNA synthesis in quiescent cultures of rat astrocytes has been examined. It was found that diazepam inhibited the ability of basic fibroblast growth factor (bFGF) to stimulate [3H]thymidine incorporation; the IC50 was approximately 5 microM. Ro5-4864, a specific agonist of PBRs, also blocked bFGF-induced DNA synthesis. PK11195, which in some cases functions as an antagonist of PBRs, did not prevent the effect of Ro5-4864 on bFGF-induced DNA synthesis; rather, addition of PK11195 also inhibited bFGF-induced DNA synthesis. In addition, diazepam reduced the stimulation of DNA synthesis caused by epidermal growth factor (EGF) and platelet-derived growth factor (PDGF), polypeptide growth factors coupled to receptor tyrosine kinases, as well as thrombin, an activator of G protein-coupled receptors. These data suggest that ligands of PBRs may limit astrocyte mitosis, a phenomenon that occurs following CNS injury.

A number of factors appear to be involved in the proliferative and hypertrophic processes which characterize reactive astrocytosis. We have investigated the possibility that ATP, an agent that is released by injured cells following tissue destruction, may be one such factor. For this purpose, we utilized primary cultures of astrocytes derived from cerebral cortices of neonatal rats to study the effect of extracellular ATP on properties associated with astrogliosis. Light microscopic studies disclosed marked stellation of astrocytes after 30-60 min of exposure to 100 microM-1 mM ATP. In addition, the content of the astrocyte-specific intermediate filament, glial fibrillary acidic protein (GFAP), was increased 35-40% following 60-min exposure to ATP; this effect persisted for 1-3 days of exposure to 100 microM ATP. [3H]Thymidine incorporation increased progressively from 1-3 days; a 3.6-fold increase in DNA synthesis was observed following 3 days of exposure to 1 mM ATP, suggesting stimulation of cellular proliferation. These findings show that high micromolar to low millimolar concentrations of extracellular ATP reproduce several features associated with reactive gliosis and suggest that extracellular ATP may be involved in the activation of astrocytes following CNS injury.