1,951 research outputs found
The detection of intentional contingencies in simple animations in patients with delusions of persecution
Background. It has been proposed that delusions of persecution are caused by the tendency to over-attribute malevolent intentions to other people's actions. One aspect of intention attribution is detecting contingencies between an agent's actions and intentions. Here, we used simplified stimuli to test the hypothesis that patients with persecutory delusions over-attribute contingency to agents' movements.
Method. Short animations were presented to three groups of subjects: (1) schizophrenic patients; (2) patients with affective disorders; and (3) normal control subjects. Patients were divided on the basis of the presence or absence of delusions of persecution. Participants watched four types of film featuring two shapes. In half the films one shape's movement was contingent on the other shape. Contingency was either ‘intentional’: one shape moved when it ‘saw’ another shape; or ‘mechanical’: one shape was launched by the other shape. Subjects were asked to rate the strength of the relationship between the movement of the shapes.
Results. Normal control subjects and patients without delusions of persecution rated the relationship between the movement of the shapes as stronger in both mechanical and intentional contingent conditions than in non-contingent conditions. In contrast, there was no significant difference between the ratings of patients with delusions of persecution for the conditions in which movement was animate. Patients with delusions of persecution perceived contingency when there was none in the animate non-contingent condition.
Conclusions. The results suggest that delusions of persecution may be associated with the over-attribution of contingency to the actions of agents
Expected correlates and outcomes of childhood gender nonconformity
Participants were presented with one of ten vignettes describing a male or female child character who varied in gender-related interests and behaviors from strongly masculine to strongly feminine.
Participants thought masculine and feminine children would be masculine and feminine in adulthood, respectively, and that masculinity would be related to externalizing and femininity to internalizing. They thought that gender-nonconforming children would experience more pressure to change their behavior, and that they would be less likely to be exclusively heterosexual in adulthood
Stochastic Dynamics of Magnetosomes in Cytoskeleton
Rotations of microscopic magnetic particles, magnetosomes, embedded into the
cytoskeleton and subjected to the influence of an ac magnetic field and thermal
noise are considered. Magnetosome dynamics is shown to comply with the
conditions of the stochastic resonance under not-too-tight constraints on the
character of the particle's fastening. The excursion of regular rotations
attains the value of order of radian that facilitates explaining the biological
effects of low-frequency weak magnetic fields and geomagnetic fluctuations.
Such 1-rad rotations are effectively controlled by slow magnetic field
variations of the order of 200 nT.Comment: LaTeX2e, 7 pages with 3 figure
Developmental changes in effects of risk and valence on adolescent decision-making
Recent research on risky decision-making in adults has shown that both the risk in potential outcomes and their valence (i.e., whether those outcomes involve gains or losses) exert dissociable influences on decisions. We hypothesised that the influences of these two crucial decision variables (risk and valence) on decision-making would vary developmentally during adolescence. We adapted a risk-taking paradigm that provides precise metrics for the impacts of risk and valence. Decision-making in 11–16 year old female adolescents was influenced by both risk and valence. However, their influences assumed different developmental patterns: the impact of valence diminished with age, while there was no developmental change in the impact of risk. These different developmental patterns provide further evidence that risk and valence are fundamentally dissociable constructs and have different influences on decisions across adolescence
Identifying earthworms (Oligochaeta, Megadrili) of the Southern Kuril Islands using DNA barcodes
Identificación de las lombrices (Oligochaeta, Megadrili) del sur de las Islas Kuriles utilizando códigos de barras de ADN Las Islas Kuriles forman un archipiélago volcánico situado entre Hokkaido y Kamchatka. En este estudio analizamos las lombrices de tres de las Islas Kuriles meridionales: Kunashir, Shikotan y Yuri, utilizando el análisis morfológico y los códigos de barras de ADN. Nuestros resultados ponen de relieve el potencial de los códigos de barras de ADN para estudiar las lombrices: si bien en estudios anteriores solo se habían registrado seis especies y subespecies de lombriz en las Islas Kuriles meridionales, nosotros detectamos 15 grupos genéticos. Seis de ellos son especies cosmopolitas europeas; seis, especies asiáticas; y tres, sin determinar. A pesar de que no se encontraron lombrices europeas en Yuri, que está deshabitada desde la Segunda Guerra Mundial, estas especies dominaron en las islas Kunashir y Shikotan, que son más grandes y están habitadas, lo que sugiere que se trata de especies invasoras recientes. De las seis especies asiáticas, cinco tenían secuencias cox1 idénticas o muy emparentadas con las secuencias publicadas encontradas en el continente o en las islas del Japón y, por tanto, se trata de invasoras recientes.The Kuril Islands are a volcanic archipelago located between Hokkaido and Kamchatka. In this study we investigated earthworm fauna of three of the Southern Kuril Islands, Kunashir, Shikotan, and Yuri, using both morphological analysis and DNA barcoding. Our results highlight the potential of DNA barcoding for studying earthworm fauna: while previous studies reported only six earthworm species and subspecies on the Southern Kurils, we detected 15 genetic clusters. Six of them correspond to European cosmopolites; six, to Asian species, and three, to unidentified species. While no European earthworms were found on Yuri that is uninhabited since WWII, they dominated on larger and inhabited Kunashir and Shikotan, suggesting that they are recent invaders. Of the six Asian species, five had cox1 sequences identical or very closely related to published sequences from the mainland or the Japanese islands and thus are recent invaders.Identificación de las lombrices (Oligochaeta, Megadrili) del sur de las Islas Kuriles utilizando códigos de barras de ADN Las Islas Kuriles forman un archipiélago volcánico situado entre Hokkaido y Kamchatka. En este estudio analizamos las lombrices de tres de las Islas Kuriles meridionales: Kunashir, Shikotan y Yuri, utilizando el análisis morfológico y los códigos de barras de ADN. Nuestros resultados ponen de relieve el potencial de los códigos de barras de ADN para estudiar las lombrices: si bien en estudios anteriores solo se habían registrado seis especies y subespecies de lombriz en las Islas Kuriles meridionales, nosotros detectamos 15 grupos genéticos. Seis de ellos son especies cosmopolitas europeas; seis, especies asiáticas; y tres, sin determinar. A pesar de que no se encontraron lombrices europeas en Yuri, que está deshabitada desde la Segunda Guerra Mundial, estas especies dominaron en las islas Kunashir y Shikotan, que son más grandes y están habitadas, lo que sugiere que se trata de especies invasoras recientes. De las seis especies asiáticas, cinco tenían secuencias cox1 idénticas o muy emparentadas con las secuencias publicadas encontradas en el continente o en las islas del Japón y, por tanto, se trata de invasoras recientes
Single-Electron Redox Chemistry on the [Cp*Rh] Platform Enabled by a Nitrated Bipyridyl Ligand
This work is licensed under a Creative Commons Attribution 4.0 International License.[Cp*Rh] complexes (Cp* = pentamethylcyclopentadienyl) are attracting renewed interest in coordination chemistry and catalysis, but these useful compounds often undergo net two-electron redox cycling that precludes observation of individual one-electron reduction events. Here, we show that a [Cp*Rh] complex bearing the 4,4′-dinitro-2,2′-bipyridyl ligand (dnbpy) (3) can access a distinctive manifold of five oxidation states in organic electrolytes, contrasting with prior work that found no accessible reductions in aqueous electrolyte. These states are readily generated from a newly isolated and fully characterized rhodium(III) precursor complex 3, formulated as [Cp*Rh(dnbpy)Cl]PF6. Single-crystal X-ray diffraction (XRD) data, previously unavailable for the dnbpy ligand bound to the [Cp*Rh] platform, confirm the presence of both [η5-Cp*] and [κ2-dnbpy]. Four individual one-electron reductions of 3 are observed, contrasting sharply with the single two-electron reductions of other [Cp*Rh] complexes. Chemical preparation and the study of the singly reduced species with electronic absorption and electron paramagnetic resonance spectroscopies indicate that the first reduction is predominantly centered on the dnbpy ligand. Comparative cyclic voltammetry studies with [NBu4][PF6] and [NBu4][Cl] as supporting electrolytes indicate that the chloride ligand can be lost from 3 by ligand exchange upon reduction. Spectroelectrochemical studies with ultraviolet (UV)-visible detection reveal isosbestic behavior, confirming the clean interconversion of the reduced forms of 3 inferred from the voltammetry with [NBu4][PF6] as supporting electrolyte. Electrochemical reduction in the presence of triethylammonium results in an irreversible response, but does not give rise to catalytic H2 evolution, contrasting with the reactivity patterns observed in [Cp*Rh] complexes bearing bipyridyl ligands with less electron-withdrawing substituents.US National Science Foundation award OIA-1833087KU Hall Chemical Research FundCenter for Undergraduate Research at the University of KansasNIH S10OD016360NIH S10RR024664NSF MRI funding (CHE-1625923
Ultrafast Spectroscopy of [Mn(CO)3] Complexes: Tuning the Kinetics of Light-Driven CO Release and Solvent Binding
This document is the Accepted Manuscript version of a Published Work that appeared in final form in Inorganic Chemistry, copyright © American Chemical Society after peer review and technical editing by the publisher. To access the final edited and published work see https://doi.org/10.1021/acs.inorgchem.9b02758.Manganese tricarbonyl complexes are promising catalysts for CO2 reduction, but complexes in this family are often photo-sensitive and decompose rapidly upon exposure to visible light. In this report, synthetic and photochemical studies probe the initial steps of light-driven speciation for Mn(CO)3(Rbpy)Br complexes bearing a range of 4,4′-disubstituted-2,2′-bipyridyl ligands (Rbpy, R = tBu, H, CF3, NO2). Transient absorption spectroscopy measurements for the Mn(CO)3(Rbpy)Br coordination compounds with R = tBu, H, and CF3 in acetonitrile reveal ultrafast loss of a CO ligand on the femtosecond timescale, followed by solvent coordination on the picosecond timescale. The Mn(CO)3(NO2bpy)Br complex is unique among the four compounds in having a longer-lived excited state that does not undergo CO release or the subsequent solvent coordination. The kinetics of photolysis and solvent coordination for the light-sensitive complexes depend on the electronic properties of the di-substituted bipyridyl ligand. The results implicate roles for both metal-to-ligand charge transfer (MLCT) and dissociative ligand field (dd) excited states in the ultrafast photochemistry. Taken together, the findings suggest that more robust catalysts could be prepared with appropriately designed complexes that avoid crossing between the excited states that drive photochemical CO loss.Hall Chemical Research Fund at the University of KansasU.S. National Science Foundation (CHE-1151555)NIH T32 GM008545-2
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