20 research outputs found
Tidal Disruption Event Demographics with the Zwicky Transient Facility: Volumetric Rates, Luminosity Function, and Implications for the Local Black Hole Mass Function
We conduct a systematic tidal disruption event (TDE) demographics analysis using the largest sample of optically selected TDEs. A flux-limited, spectroscopically complete sample of 33 TDEs is constructed using the Zwicky Transient Facility over 3 yr (from 2018 October to 2021 September). We infer the black hole (BH) mass (M BH) with host galaxy scaling relations, showing that the sample M BH ranges from 105.1 M â to 108.2 M â. We developed a survey efficiency corrected maximum volume method to infer the rates. The rest-frame g-band luminosity function can be well described by a broken power law of Ï ( L g ) â L g / L bk 0.3 + L g / L bk 2.6 â 1 , with L bk = 1043.1 erg sâ1. In the BH mass regime of 105.3 âČ (M BH/M â) âČ 107.3, the TDE mass function follows Ï ( M BH ) â M BH â 0.25 , which favors a flat local BH mass function ( dn BH / d log M BH â constant ). We confirm the significant rate suppression at the high-mass end (M BH âł 107.5 M â), which is consistent with theoretical predictions considering direct capture of hydrogen-burning stars by the event horizon. At a host galaxy mass of M gal ⌠1010 M â, the average optical TDE rate is â3.2 Ă 10â5 galaxyâ1 yrâ1. We constrain the optical TDE rate to be [3.7, 7.4, and 1.6] Ă 10â5 galaxyâ1 yrâ1 in galaxies with red, green, and blue colors
Mapping autobiographical memory in schizophrenia: Clinical implications.
Increasing evidence suggests that impaired autobiographical memory (AM) mechanisms may be associated with the onset and maintenance of psychopathology. However, there is not yet a comprehensive review of the components of autobiographical memory in schizophrenic patients. The first aim of this review is a synthesis of evidence about the functioning of AM in schizophrenic patients. The main autobiographical elements reviewed in schizophrenic patients include the study of overgeneral memory (form); self-defining memories (contents); consciousness during the process of retrieval (awareness), and the abnormal early reminiscence bump (distribution). AM impairments have been involved in the clinical diagnosis and prognosis of other psychopathologies, especially depression. The second aim is to examine potential parallels between the mechanisms responsible for the onset and maintenance of disturbed AM in other clinical diagnosis and the mechanisms of disturbed autobiographical memory functioning in schizophrenic patients. Cognitive therapies for schizophrenic patients are increasingly demanded. The third aim is the suggestion of key elements for the adaptation of components of autobiographical recall in cognitive therapies for the treatment of symptoms and consequences of schizophrenia
Psychometric Properties of the Spanish Short Depressive Rumination Scale in a Nonclinical Sample
Repetitive negative thinking (RNT) is considered a transdiagnostic variable underlying common symptoms (e.g., depressed mood) across various mood disorders. Depressive rumination is one typical and frequent manifestation of RNT and is a well-known vulnerability factor of depression onset, maintenance and recurrence. Due to the time-related constraints in assessment settings and the association of rumination on sadness with diagnosis of depression, the rapid identification of individuals scoring high on this construct may become a useful screening tool in non-clinical samples. The main aim of the present study was to test the psychometric properties of the Spanish version of the Short Depressive Rumination Scale (SDRS) in a large sample (N = 649). Confirmatory Factor Analysis supported a one-factor model accounting for 75% of variance with an excellent internal consistency (α = .93) in spite of the reduced number of items (4 items). Criterion validity results based on associations with other well-established rumination (sub)scales, age, scores in depression and gender differences, were congruent. The results suggest that the SDRS, the shortest existing scale assessing depressive rumination to our knowledge, can be a useful instrument for a rapid assessment of depressive rumination in community samples.status: Published onlin
Age and gender differences in emotion regulation strategies: autobiographical memory, rumination, problem solving and distraction
This is the author accepted manuscript. The final version is available from the publisher via the DOI in this record.Our study tested the hypothesis that older adults and men use more adaptive emotion regulatory strategies but fewer negative emotion regulatory strategies than younger adults and women. In addition, we tested the hypothesis that rumination acts as a mediator variable for the effect of age and gender on depression scores. Differences in rumination, problem solving, distraction, autobiographical recall and depression were assessed in a group of young adults (18-29 years) compared to a group of older adults (50-76 years). The older group used more problem solving and distraction strategies when in a depressed state than their younger counterparts (ps .06). Ordinary least squares regression analyses with bootstrapping showed that rumination mediated the association between age, gender and depression scores. These results suggest that older adults and men select more adaptive strategies to regulate emotions than young adults and women with rumination acting as a significant mediator variable in the association between age, gender, and depression