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Genome-wide association study of major anxiety disorders in 122,341 European-ancestry cases identifies 58 loci and highlights GABAergic signaling
No full textThe major anxiety disorders (ANX; including generalized anxiety disorder, panic disorder and phobias) are highly prevalent, often onset early and cause substantial global disability. Although distinct in their clinical presentations, they probably represent differential expressions of a dysregulated threat–response system. Here, we present a genome-wide association meta-analysis comprising 122,341 European ancestry ANX cases and 729,881 controls. We identified 58 independent genome-wide significant risk variants and 66 genes with robust biological support. In an independent sample of 1,175,012 self-report ANX cases and 1,956,379 controls, 51 out of the 58 associations replicated. As predicted by twin studies, we found substantial genetic correlation between ANX and depression, neuroticism and other internalizing phenotypes. Follow-up analyses demonstrated enrichment in all major brain regions and highlighted GABAergic signaling as one potential mechanism implicated in ANX genetic risk. These results advance our understanding of the genetic architecture of ANX and prioritize genes for functional follow-up studies
Dynamic models for two nonreciprocally coupled fields: A microscopic derivation for zero, one, and two conservation laws
No full textWe construct dynamic models governing two nonreciprocally coupled fields for several cases with zero, one, and two conservation laws. Starting from two microscopic nonreciprocally coupled Ising models, and using the mean-field approximation, we obtain closed-form evolution equations for the spatially resolved magnetization in each lattice. Only allowing for single spin-flip dynamics, the macroscopic equations in the thermodynamic limit are closely related to the nonreciprocal Allen-Cahn equations, i.e., conservation laws are absent. Likewise, only accounting for spin-exchange dynamics within each lattice, the thermodynamic limit yields equations similar to the nonreciprocal Cahn-Hilliard model, i.e., with two conservation laws. In the case of spin-exchange dynamics within and between the two lattices, we obtain two nonreciprocally coupled equations that add up to one conservation law. For each of these cases, we systematically map out the linear instabilities that can arise. Moreover, combining the different dynamics gives a large number of further models. Our results provide a microscopic foundation for a broad class of nonreciprocal field theories, establishing a direct link between non-equilibrium statistical mechanics and macroscopic continuum descriptions
The ro-vibrational spectroscopy of H2NCO (2A′) and HNCOH and the peculiar case of their isomers cis- and trans-HNCHO
No full textWhile quantum chemical treatment of the prebiotic, astrochemically relevant H2NCO molecule's rotational constants and fundamental vibrational frequencies produces exceptionally accurate values, the cis-HNCHO isomer is more of a challenge to standard electronic structure methods. The trans-HNCHO conformer is well-behaved like H2NCO due to the nature of the local potential energy surface, but the zero-point vibrational energy of the torsional motion is significantly greater than the barrier, implying that this isomer cannot be observed. The 2.6 kcal mol(-1) lower-energy cis-HNCHO conformer showcases a small pseudo-Jahn-Teller distortion about the HNCO torsion coordinate at planarity. This produces a challenging environment for the quartic force field (QFF) treatment of the rotational and vibrational spectroscopic data. Even so, the accuracy of the H2NCO spectroscopic constants from this explicitly correlated coupled cluster theory QFF implies that similar accuracy should be present for the mathematically well-behaved trans-HNCHO, which exists in a shallow but true minimum. The constants computed herein may allow for a more detailed search of experimental rotation spectra for cis-HNCHO, which would provide reference data necessary for potential searches for this molecule in space. Rotational constants are also provided for the four conformers of HNCOH, and the fundamental vibrational frequencies in the range of James Webb Space Telescope observation are provided for all isomers in order to allow for the possibility of multiple wavelength observation of this family of molecules, which may play a role in the molecular origins of life
The Galaxy Activity, Torus, and Outflow Survey (GATOS) X. Molecular gas clumpiness under the influence of AGN
No full textThe distribution of molecular gas on small scales regulates star formation and the growth of supermassive black holes in galaxy centers. Yet, the role of active galactic nuclei (AGN) feedback in shaping this distribution remains poorly constrained. We investigate how AGNs influence the small-scale structure of molecular gas in galaxy centers by measuring the clumpiness of CO(3 - 2) emission observed with the Atacama Large Millimeter/submillimeter Array (ALMA) in the nuclear regions (50 - 200 pc from the AGNs) of 16 nearby Seyfert galaxies from the Galaxy Activity, Torus, and Outflow Survey (GATOS). To quantify clumpiness we applied three different methods: (1) the median of the pixel-by-pixel contrast between the original and smoothed maps; (2) the ratio of the total excess flux to the total flux, after subtracting the background smoothed emission; and (3) the fraction of total flux coming from clumpy regions, interpreted as the mass fraction in clumps. We find a negative correlation between molecular gas clumpiness and AGN X-ray luminosity (L-X), suggesting that higher AGN activity is associated with smoother gas distributions. All methods reveal a turnover in this relation around L-X = 10(42) erg s(-1), possibly indicating a threshold above which AGN feedback becomes efficient at dispersing dense molecular structures and suppressing future star formation. Our findings provide new observational evidence that AGN feedback can smooth out dense gas structures in galaxy centers
Homological stratification and descent
No full textWe introduce a notion of stratification for rigidly-compactly generated tensor-triangulated categories relative to the homological spectrum and develop the fundamental features of this theory. In particular, we demonstrate that it exhibits excellent descent properties. In conjunction with Balmer’s Nerves of Steel conjecture, we conclude that classical stratification also admits a general form of descent. This gives a uniform treatment of several recent stratification results and provides a complete answer to the question: When does stratification descend? As a new application, we extend earlier work on the tensor triangular geometry of equivariant module spectra from finite groups to compact Lie groups
Neural signatures of model-based and model-free reinforcement learning across prefrontal cortex and striatum
No full textAnimals integrate knowledge about how the state of the environment evolves to choose actions that maximise reward. Such goal-directed behaviour - or model-based (MB) reinforcement learning (RL) - can flexibly adapt choice to changes, being thus distinct from simpler habitual - or model-free (MF) RL - strategies. Previous inactivation and neuroimaging work implicates prefrontal cortex (PFC) and the caudate striatal region in MB-RL; however, details are scarce about its implementation at the single-neuron level. Here, we recorded from two PFC regions - the dorsal anterior cingulate cortex (ACC) and dorsolateral PFC (DLPFC), and two striatal regions, caudate and putamen - while two rhesus macaques performed a sequential decision-making (two-step) task in which MB-RL involves knowledge about the statistics of reward and state transitions. All four regions, but particularly the ACC, encoded the rewards received and tracked the probabilistic state transitions that occurred. However, ACC (and to a lesser extent caudate) encoded the key variables of the task - namely the interaction between reward, transition and choice - which underlies MB decision-making. ACC and caudate neurons also encoded MB-derived estimates of choice values. Moreover, caudate value estimates of the choice options flipped when a rare transition occurred, demonstrating value update based on structural knowledge of the task. The striatal regions were unique (relative to PFC) in encoding the current and previous rewards with opposing polarities, reminiscent of dopaminergic neurons, and indicative of a MF prediction error. Our findings provide a deeper understanding of selective and temporally dissociable neural mechanisms underlying goal-directed behaviour
From interoception to control over the internal body: The ideomotor hypothesis of voluntary interoaction
No full textWhen it comes to body movements in external space, people are experts in learning fine-grained voluntary control, for example, when manipulating tiny objects. Voluntarily controlling actions in the internal body (e.g., decreasing heart rate), however, is far more difficult and requires dedicated training, for example, in meditation or yoga. Not much is currently known about the learning mechanism underlying the acquisition of voluntary control over internal visceromotor actions (i.e., interoaction) or why it is so difficult compared to controlling our external somatomotor actions (i.e., exteroaction). We propose the ideomotor hypothesis of voluntary interoaction in this article, which asserts that voluntary exteroactions and interoactions are governed by the same general principle, namely, the anticipation of sensory feedback. We apply this hypothesis to two techniques that can be used to acquire voluntary control over interoactions, that is, autogenic training and biofeedback training. As the afferent signal we receive from interoaction (i.e., interoceptive signals from the internal body) is of lower sensory quality than the afferent signal that we receive from exteroaction (i.e., exteroceptive signals from the external environment), this hypothesis explains why learning to control interoactions is more difficult. We propose ways in which to test predictions from this hypothesis and show its theoretical value by comparing it to other frameworks in the literature. We hope that this work motivates future empirical studies directly examining voluntary interoaction and its clinical applications, such as autogenic and biofeedback training, and mind-body practices more generally
No morphological connections between L2 past-tense and present-tense verbs for low-proficient bilinguals: Evidence from masked priming
Full text linkAims and objectives:Masked priming lexical decision research involving relatively high-proficient Japanese–English bilinguals suggests that past-tense and present-tense morphological connections (e.g., fell-FALL and looked-LOOK) are represented in their L2 (English) lexicons in a way that is similar to how they are represented in L1 (English) lexicons. The goal of the present research was to determine whether the same is true for low-proficient Japanese–English bilinguals.Methodology:Seventy-seven low-proficient Japanese–English bilinguals were tested in the masked priming lexical decision task. We manipulated the morphological or orthographic similarity between L2 English prime-target pairs.Data and analysis:We analyzed response latencies and error rates using (generalized) linear mixed-effects models.Findings:Although participants responded significantly faster to targets preceded by past-tense primes (e.g., fell-FALL and looked-LOOK) when compared to unrelated primes (e.g., slow-FALL and danger-LOOK), those priming effects were the same size as priming effects produced by orthographically similar primes (e.g., fill-FALL and lonely-LOOK), suggesting that the facilitation from past-tense primes is likely orthographic in nature. Nevertheless, the low-proficient bilinguals showed significant L2-L2 repetition priming (e.g., fall-FALL and look-LOOK), suggesting that, for those individuals, L2 (English) words are at least represented at the lexical level.Originality:The present study empirically confirmed a prediction, derived from a post hoc exploratory analysis in our previous research, that masked morphological priming effects are no larger than orthographic priming effects in low-proficient bilinguals. This indicates that a certain level of functional proficiency is required to observe morphological priming effects for Japanese–English bilinguals.Implications:Our results suggest that morphological connections in L2 are not yet established for low-proficient bilinguals, even when L2 words are lexically represented in their mental lexicon
Pythagoras numbers for infinite algebraic fields
No full textWe prove that the Pythagoras number of the ring of integers of the compositum of all real quadratic fields is infinite. The same holds for certain infinite totally real cyclotomic fields. In contrast, we construct infinite degree totally real algebraic fields whose rings of integers have finite Pythagoras numbers, namely, one, two, three, and at least four