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The first record of symbiosis between a new species of scaleworm (Polychaeta, Polynoidae) with fungiid corals (Scleractinia, Fungiidae)
No full textAmong scleractinian coral-associated symbionts, polychaetes contribute relatively less to overall species richness compared to crustaceans and mollusks, with only 40 documented symbiotic species. Notably, scaleworm (Polynoidae) diversity on scleractinian corals remains remarkably low, with just nine species recorded to date. During biodiversity surveys in the Tho Chu Archipelago (southern Vietnam), we discovered polynoid polychaetes inhabiting fungiid corals Pleuractis moluccensis and Fungia fungites. Specimens were collected, preserved in ethanol, and examined through morphological and molecular analyses, leading to the formal description of Hololepidella martini sp. nov. This new species is distinguished from congeners by: (1) its exclusive association with fungiid corals, (2) the presence of only bidentate neurochaetae, and (3) a uniformly white or yellowish body lacking distinctive pigmentation. Molecular analyses of COI gene fragments further support the distinction between H. martini and its closest relative, H. nigropunctata, revealing 14–15% genetic divergence. Field surveys showed significantly higher prevalence on P. moluccensis (33%, n = 78) than on F. fungites (6%, n = 65), suggesting the former serves as the primary host, while the latter is a secondary alternative. This discovery represents only the fourth known species of coral-associated polynoids, highlighting both the rarity of such symbioses and the need for further research on coral-polychaete relationships.</p
The reputational consequences of victim signaling
No full textWe examine how victim signaling, defined as publicly sharing experiences of suffering caused by disadvantage, harm, or limitations, affects how observers perceive the signaler. We conducted four studies ( N Total = 1430) on diverse samples (i.e., online participants and professionals in the Philippines), using different methodologies (i.e., employee-coworker dyads and vignette-based experiments), and ways of victim-signaling (i.e., contentious vs. subtle). Across contexts, we found that people who signal their victimhood were evaluated more negatively than those who did not emit this signal, despite the latter facing similar circumstances. We found this effect on a range of social judgments, including ratings of dark traits (Dark Triad and D) and perceived desirability of the signaler as a social partner (e.g., job performance ratings and perceptions of counterproductive workplace behavior). A post-hoc analysis in Studies 3 and 4 found that political beliefs moderated perceptions of victim signalers from minority groups; compared to conservatives, liberals were less likely to see victimhood signalers (vs. non-signalers) as narcissistic and psychopathic (Study 3) and were less likely to infer entitlement–Machiavellian traits from a victim-signaling candidate (Study 4). Our results contribute to understanding how victim signaling shapes social perception and the complexities of interpreting claims of harm.</p
Oxygen permeability and stability in the entropy-stabilized Co-based perovskite oxygen permeable membranes
No full textOxygen transport membranes (OTMs), enabling catalytic reaction and gas separation, support crucial chemical engineering processes and decarbonization technologies, but their applications are hindered by limited oxygen permeation fluxes and inadequate long-term stability during operation. Here, a series of high-entropy perovskite oxygen transport membranes (OTMs) based on La0.5Sr0.5CoO3 (LSC) were designed and synthesized by the simple sol-gel method. The impact of varying doping ratios on the structure, surface morphology, oxygen permeability, and stability of these high-entropy OTMs was thoroughly examined. At 950 °C, the optimal composition, La0.25Sr0.25Gd0.2Nd0.2Pr0.1CoO3, achieved oxygen permeation fluxes of 1.62 mL min−1·cm−2 under air/He gradient and 1.46 mL min−1·cm−2 under air/CO2, respectively. Remarkably, all high-entropy OTMs demonstrated stable operation for over 100 h in a pure CO2 environment without a significant decline in performance. This finding paves a new way to enhance the structural and oxygen permeation stability of OTMs, and further promotes the application of OTMs in oxy-fuel combustion technologies aimed at improving CO2 capture and storage efficiency.</p
Integrating [11C]methylreboxetine PET and MRI to map in vivo norepinephrine transporter distribution:A proof-of-concept study of noradrenergic vulnerability in neurodegeneration
No full textBACKGROUND: The locus coeruleus (LC) and its noradrenergic projections are among the earliest sites displaying pathology in Alzheimer's disease (AD) and Parkinson's disease (PD). In vivo measures of norepinephrine transporter (NET) availability with [11C]methylreboxetine ([11C]MRB) positron emission tomography (PET) and structural magnetic resonance imaging (MRI) indices of LC integrity provide complementary, but rarely integrated biomarkers.METHODS: 13 Healthy controls (HC), individuals with 12 AD or amnestic mild cognitive impairment due to AD (AD/aMCI), and 5 patients with PD underwent [11C]MRB PET and high-resolution T1-weighted MRI. NET availability was quantified using [11C]MRB PET SUV-ratio-based binding potential (SUVr-BP) in the LC and projection regions (hippocampus, amygdala, thalamus, and prefrontal cortex). LC structural integrity was indexed by LC MRI contrast-to-noise ratio (CNR), and projection region volumes were extracted with FreeSurfer. Group differences were assessed with Kruskal-Wallis tests, and PET-MRI associations were examined using Pearson correlations with Yeo-Johnson transformation to reduce outlier influence.RESULTS: No significant group-level differences in [11C]MRB PET SUVr-BP or MRI measures were observed across HC, AD/aMCI, and PD. However, LC [11C]MRB PET SUVr-BP correlated with LC MRI-CNR (r = 0.429, 95 % CI [0.082-0.684], p = 0.018). In contrast, PET-MRI associations in projection regions were weak and non-significant. Exploratory analyses confirmed expected differences in cognition, neuropsychiatric symptoms, and functional measures, most pronounced in AD/aMCI participants.CONCLUSIONS: This proof-of-concept study demonstrates convergent multimodal assessment of LC integrity using [11C]MRB PET and LC MRI-CNR, whereas projection regions showed divergent or absent associations. These findings highlight the potential of the LC as a target for multimodal biomarker development and support further investigation of these imaging strategies in larger, longitudinal cohorts to delineate their role in detecting noradrenergic vulnerability in neurodegeneration.SIGNIFICANCE STATEMENT: This study integrates [11C]MRB PET and MRI to examine noradrenergic integrity in Alzheimer's and Parkinson's disease. Results demonstrate strong PET-MRI convergence in the locus coeruleus, but not in projection regions, highlighting the locus coeruleus as a sensitive biomarker target and supporting multimodal imaging approaches for early detection of neurodegenerative vulnerability.</p
Contributions of Mindfulness to the Treatment of Anxiety
No full textAnxiety disorders are among the most common classes of mental disorders and come with heavy personal and societal burdens. The current gold standard for the treatment of anxiety disorders is cognitive behavioral therapy (CBT). Although effective, a significant proportion of people with anxiety disorders do not sufficiently benefit from treatment, making it important for researchers to seek ways to maximize treatment effectiveness. Mindfulness-based interventions represent a promising treatment approach for anxiety symptoms. This chapter provides an overview of theories of anxiety and how mindfulness can be beneficial in its treatment. Research on the mechanisms of mindfulness in the reduction of anxiety symptoms is reviewed, and a case is made for its potential effect on intolerance of uncertainty. The chapter concludes with a summary and brief discussion of future research avenues.</p
Endocrine and metabolic determinants of cardiometabolic risk in mild autonomous cortisol secretion
No full textBACKGROUND: Benign adrenal tumours, found in 1-7% of adults, can be non-functioning (NFAT) or show mild autonomous cortisol secretion (MACS), i.e., biochemical cortisol excess without manifestations of Cushing's syndrome (CS). MACS occurs in 20-50% of cases and is linked to increased cardiometabolic burden.METHODS: In a cross-sectional study, we analysed the 24-h urinary steroid metabolome of 1305 prospectively recruited patients (649 NFAT, 591 MACS, 65 adrenal CS) by tandem mass spectrometry. A sub-group (104 NFAT, 140 MACS, 47 adrenal CS) underwent untargeted serum metabolome analysis by mass spectrometry. Data were analysed using linear regression and supervised machine learning.FINDINGS: Alongside the expected increase in glucocorticoid excretion from NFAT over MACS to adrenal CS, steroid analysis revealed decreased classic androgen metabolite excretion. By contrast, adrenal-derived 11-oxygenated androgen metabolites remained unchanged. Both glucocorticoid metabolites and the major 11-oxygenated androgen metabolite 11β-hydroxyandrosterone correlated with a higher risk of hypertension and type 2 diabetes. Untargeted metabolome analysis revealed gradual changes towards a lipotoxic phenotype from NFAT over MACS to adrenal CS, with perturbations in glycerophospholipids, lysoglycerophospholipids, triacylglycerides, ceramides, sphingolipids, and acylcarnitines.INTERPRETATION: MACS represents a metabolic continuum between NFAT and adrenal CS. Increased activity of the adrenal enzyme 11β-hydroxylase (CYP11B1), which catalyses key steps in cortisol and 11-oxygenated androgen biosynthesis, may contribute to steroid excess and cardiometabolic morbidity in MACS. These findings suggest that CYP11B1 may be a potential therapeutic target to ameliorate metabolic dysfunction in MACS.FUNDING: NIHR Birmingham Biomedical Research Centre; Diabetes UK; Wellcome Trust; European Commission; Medical Research Council.</p
Yoga van Spinoza:Kracht uitoefenen en het Oneindige ervaren
No full textVandaag de dag heeft de mens ongekende macht (wetenschappelijk, technologisch, militair en politiek) tot zijn beschikking, waar de hele planeet grondig voor getransformeerd moest worden. Toch wordt de mensheid op het hoogtepunt van deze macht geconfronteerd met uitdagingen waar ze volkomen machteloos tegenover lijkt te staan, van scheve sociaaleconomische verhoudingen tot klimaatrampen. De filosofie van Baruch Spinoza (1631-1677) kan een nieuw perspectief bieden om de kern van deze paradox te begrijpen en tot een mogelijke oplossing te komen. Spinoza geeft aan hoe effectieve versterking moet resulteren in een verbetering van het soort kennis waartoe we toegang hebben; en hoe, in het proces van versterking, op natuurlijke wijze een onbeperkte en onuitputtelijke bron van vitale energie ontdekt wordt, met name in de kennis van hoe elk individueel wezen deel en uitdrukking van het geheel is.Om deze beweringen echter op waarde te kunnen schatten en ernaar te kunnen handelen is het nodig Spinoza niet alleen te lezen als een theoreticus of metafysicus uit een ver verleden, maar als een beoefenaar van die contemplatieve disciplines die in India al duizenden jaren ‘yoga’ worden genoemd. Net zoals de meeste Indiase scholen benadert Spinoza’s yoga het gewone leven kritisch, maar in tegenstelling tot deze scholen wordt de oplossing niet gezocht in het uitbannen van het menselijk verlangen, maar in de diepere en intensere bekrachtiging ervan.Op deze wijze is Spinoza’s yoga geen onleesbare formule, maar een duidelijk recept dat de manier waarop we de wereld bewonen kan transformeren. Tegelijkertijd stelt Spinoza’s yoga ons in staat thema’s en praktijken uit Indiase yogatradities te heroverwegen en te problematiseren, waardoor we met een frisse blik naar hun waarde en toepasbaarheid kunnen kijken
A 28-year record of the isotopic niche of baleen whales in the Gulf of St. Lawrence, Canada:A perspective on ecosystem changes and potential for food competition.
No full textFin whales (Balaenoptera physalus), humpback whales (Megaptera novaeangliae)and minke whales (Balaenoptera acutorostrata) seasonally coexist in sympatry inthe Gulf of St. Lawrence (Canada) where they feed to replenish their energyreserves. Over the past decades, these three species have experienced significantshifts in resource availability as the St. Lawrence ecosystem encountered majortrophodynamic changes due to climatic and anthropogenic perturbations. Thisstudy aimed to understand how the realized trophic niche of these rorqualspecies has changed over time. To achieve this objective, stable nitrogen andcarbon isotope ratios from 1110 whale skin biopsies sampled between 1992 and2019 were used to define the isotopic niche of each species, quantify their dietusing Bayesian isotopic mixing models, and assess the degree of individual dietspecialization. Resource partitioning among these three sympatric speciesincreased during the 2011–2019 period, as highlighted by the limited overlapobserved among their isotopic niches. A recent dietary shift toward an increasedreliance on pelagic fish (capelin, herring and/or mackerel) in fin whale and minkewhale and a reduced contribution of krill suggests a possible reduction in krillabundance in the Gulf of St. Lawrence in recent years. These findings provide aunique insight into the ability of three generalist species to coexist throughpartitioning food resources, and adapt to ecosystem changes. Given the climaticcontext, knowledge of preferred prey is crucial for the conservation ofthese species
Structure-function relationship of the molecular chaperone DNAJB6b at atomistic resolution
No full textProteins must fold and assemble correctly to maintain cellular function. When this process fails, aberrant aggregation and phase separation can lead to disease. This thesis investigates the molecular mechanisms by which the molecular chaperone DNAJB6b suppresses aggregation of polyglutamine rich proteins, with a focus on understanding how sequence features and conformational dynamics regulate chaperone activity.Using a combination of all atom and coarse grained molecular dynamics simulations, this work dissects the conformational landscape of DNAJB6b and its interactions with aggregation prone substrates. Particular attention is given to the autoinhibitory mechanism of DNAJB6b and to how specific residues stabilize this regulatory state, as well as how this autoinhibition is released upon interaction with client proteins.In parallel, a coarse grained modeling framework is developed and calibrated against all atom simulations to study polyglutamine aggregation across length and time scales beyond the reach of atomistic models, and to examine how chaperones influence these processes.Together, these approaches provide molecular insight into how chaperones modulate protein aggregation and phase behavior, and establish computational strategies for studying sequence dependent aggregation mechanisms. The results contribute to a mechanistic understanding of proteostasis and offer a foundation for exploring chaperone dependent pathways in protein misfolding diseases