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Developmental plasticity, where traits change state in response to environmental cues, is well studied in modern populations. It is also suspected to play a role in macroevolutionary dynamics, but due to a lack of long-term records, the frequency of plasticity-led evolution in deep time remains unknown. Populations are dynamic entities, yet their representation in the fossil record is a static snapshot of often isolated individuals. Here, we apply for the first time contemporary integral projection models (IPMs) to fossil data to link individual development with expected population variation. IPMs describe the effects of individual growth in discrete steps on long-term population dynamics. We parameterize the models using modern and fossil data of the planktonic foraminifer Trilobatus sacculifer. Foraminifera grow by adding chambers in discrete stages and die at reproduction, making them excellent case studies for IPMs. Our results predict that somatic growth rates have almost twice as much influence on population dynamics than survival and more than eight times more influence than reproduction, suggesting that selection would primarily target somatic growth as the major determinant of fitness. As numerous paleobiological systems record growth rate increments in single genetic individuals and imaging technologies are increasingly available, our results open up the possibility of evidence-based inference of developmental plasticity spanning macroevolutionary dynamics. Given the centrality of ecology in paleobiological thinking, our model is one approach to help bridge eco-evolutionary scales while directing attention toward the most relevant life-history traits to measure.
Large carnivores are frequently released for conservation purposes, but early efforts struggled with inadequate monitoring and reporting, resulting in poor understanding of success. Although managers have improved release practice and monitoring, the use of orphaned, captive-raised large carnivores for release remains controversial because of the potential influence of captivity and the possible lack of natural behaviours in such individuals. Yet, rehabilitating orphaned individuals for release could help mitigate pressures on vulnerable wild populations. We present a case study on the rearing, rehabilitation and release of wild-born cheetahs Acinonyx jubatus that were rescued as orphans in Namibia. Our aim was to develop a methodological framework for cheetah release planning and post-release management based on the outcome of release trials conducted during 2004–2018. Between 2001 and 2012, we rescued 86 orphaned cheetahs from the wild. Of these, 36 (42%) were selected as release candidates. We found high success rates (75–96%) of selected individuals in achieving independence post-release. Additionally, annual survival estimates for rehabilitated individuals that reached independence were comparable to those of wild counterparts described by other studies, and some rehabilitated individuals reproduced with wild conspecifics. Our findings demonstrate the ability of wild-born, captive-raised cheetahs to transition back into the wild with strategic pre- and post-release management directed towards optimizing survival. This includes selecting appropriate release candidates, forming artificial coalitions, balancing habituation levels during captivity, choosing appropriate release sites, and providing strategic support during post-release monitoring. We encourage scientists and managers to implement and refine our protocol for rehabilitation throughout the cheetah's current and historic range.
The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic, with its impact on our way of life, is affecting our experiences and mental health. Notably, individuals with mental disorders have been reported to have a higher risk of contracting SARS-CoV-2. Personality traits could represent an important determinant of preventative health behaviour and, therefore, the risk of contracting the virus.
We examined overlapping genetic underpinnings between major psychiatric disorders, personality traits and susceptibility to SARS-CoV-2 infection.
Linkage disequilibrium score regression was used to explore the genetic correlations of coronavirus disease 2019 (COVID-19) susceptibility with psychiatric disorders and personality traits based on data from the largest available respective genome-wide association studies (GWAS). In two cohorts (the PsyCourse (n = 1346) and the HeiDE (n = 3266) study), polygenic risk scores were used to analyse if a genetic association between, psychiatric disorders, personality traits and COVID-19 susceptibility exists in individual-level data.
We observed no significant genetic correlations of COVID-19 susceptibility with psychiatric disorders. For personality traits, there was a significant genetic correlation for COVID-19 susceptibility with extraversion (P = 1.47 × 10−5; genetic correlation 0.284). Yet, this was not reflected in individual-level data from the PsyCourse and HeiDE studies.
We identified no significant correlation between genetic risk factors for severe psychiatric disorders and genetic risk for COVID-19 susceptibility. Among the personality traits, extraversion showed evidence for a positive genetic association with COVID-19 susceptibility, in one but not in another setting. Overall, these findings highlight a complex contribution of genetic and non-genetic components in the interaction between COVID-19 susceptibility and personality traits or mental disorders.
Studying phenotypic and genetic characteristics of age at onset (AAO) and polarity at onset (PAO) in bipolar disorder can provide new insights into disease pathology and facilitate the development of screening tools.
To examine the genetic architecture of AAO and PAO and their association with bipolar disorder disease characteristics.
Genome-wide association studies (GWASs) and polygenic score (PGS) analyses of AAO (n = 12 977) and PAO (n = 6773) were conducted in patients with bipolar disorder from 34 cohorts and a replication sample (n = 2237). The association of onset with disease characteristics was investigated in two of these cohorts.
Earlier AAO was associated with a higher probability of psychotic symptoms, suicidality, lower educational attainment, not living together and fewer episodes. Depressive onset correlated with suicidality and manic onset correlated with delusions and manic episodes. Systematic differences in AAO between cohorts and continents of origin were observed. This was also reflected in single-nucleotide variant-based heritability estimates, with higher heritabilities for stricter onset definitions. Increased PGS for autism spectrum disorder (β = −0.34 years, s.e. = 0.08), major depression (β = −0.34 years, s.e. = 0.08), schizophrenia (β = −0.39 years, s.e. = 0.08), and educational attainment (β = −0.31 years, s.e. = 0.08) were associated with an earlier AAO. The AAO GWAS identified one significant locus, but this finding did not replicate. Neither GWAS nor PGS analyses yielded significant associations with PAO.
AAO and PAO are associated with indicators of bipolar disorder severity. Individuals with an earlier onset show an increased polygenic liability for a broad spectrum of psychiatric traits. Systematic differences in AAO across cohorts, continents and phenotype definitions introduce significant heterogeneity, affecting analyses.
Being subjected to childhood maltreatment has devastating long-term adverse effects and is a major risk factor for mental health problems in adult life. There is empirical support that socio-political factors can be risk factors for childhood maltreatment. Here we examine whether socio-political context predicts self-rated childhood maltreatment in a sample of the German population.
Data were drawn from surveys of representative samples of the East and West German population, including participants born 1980 or earlier (5836 participants; 3146 women). Childhood maltreatment was assessed using the Childhood Trauma Screener, the German short screening version of the childhood trauma questionnaire. To examine whether socio-political context is a predictor of childhood maltreatment in women and men, we conducted logistic regression analyses.
We found that in women, socio-political context (West Germany) significantly predicted childhood maltreatment (odds ratio [95% confidence interval] 1.7 [1.2–2.5], 1.6 [1.1–2.3], 2.5 [1.6–4.1] and 1.8 [1.3–2.5] for emotional neglect, and emotional, physical and sexual violence, respectively). In men, the socio-political context (West Germany) was a predictor of physical and sexual violence (odds ratio [95% confidence interval] 1.8 [1.2–2.7] and 2.5 [1.4–4.5]), respectively. Concerning emotional neglect and violence, socio-political context was not a significant predictor in men. The examination of differential item functioning revealed that our results could not be attributed to differential response behaviour between East and West Germans caused by item bias.
The results suggest that socio-political context is an important determinant to consider when examining childhood maltreatment. Future research should continue to focus on risk and protective factors at the societal level, such as legal frameworks addressing gender equality and child protection laws, to create further evidence for population-wide prevention strategies ensuring safe, nurturing and thriving environments for children and families.
Most measures of anxious avoidance are limited to disorder-specific mechanisms and ignore the measurement of courage/approach responding in confronting fearful situations.
The purpose of the present study was to construct and validate a self-report assessment of the tendency towards avoidant or approach responding in fearful situations, the Response to Fearful Situations Scale (RFSS).
Method and Results:
In Study 1 (n = 241), exploratory factor analysis resulted in two factors, avoidance and approach. Study 2 (n = 423) replicated the two-factor structure and established test–re-test reliability. In Study 3 (n = 44), the RFSS demonstrated predictive validity on a behavioural avoidance task. In Studies 4 (n = 253) and 5 (n = 256), the RFSS was associated with clinical symptoms above existing measures of avoidance.
These results validate the use of the RFSS as a transdiagnostic measure of avoidance and approach.
The impact of a collapsing gas bubble above rigid, notched walls is considered. Such surface crevices and imperfections often function as bubble nucleation sites, and thus have a direct relation to cavitation-induced erosion and damage structures. A generic configuration is investigated numerically using a second-order accurate compressible multi-component flow solver in a two-dimensional axisymmetric coordinate system. Results show that the crevice geometry has a significant effect on the collapse dynamics, jet formation, subsequent wave dynamics and interactions. The wall-pressure distribution associated with erosion potential is a direct consequence of development and intensity of these flow phenomena.
Purpose of this study was to assess subjective well-being in schizophrenia inpatients and to find variables predictive for response and remission of subjective well-being.
The subjective well-being under neuroleptic treatment scale (SWN-K) was used in 232 schizophrenia patients within a naturalistic multicenter trial. Early response was defined as a SWN-K total score improvement of 20% and by at least 10 points within the first 2 treatment weeks, response as an improvement in SWN-K total score of at least 20% and by at least 10 points from admission to discharge and remission in subjective well-being as a total score of more or equal to 80 points at discharge. Logistic regression and CART analyses were used to determine valid predictors of subjective well-being outcome.
Twenty-nine percent of the patients were detected to be SWN-K early responders, 40% fulfilled criteria for response in subjective well-being and 66% fulfilled criteria for remission concerning subjective well-being. Among the investigated predictors, SWN-K early improvement and the educational status were significantly associated with SWN-K response. The SWN-K total score at baseline showed a significant negative predictive value for response. Baseline SWN-K total score, PANSS global subscore, and side effects as well as the educational status were found to be significantly predictive for remission.
Depressive symptoms should be radically treated and side effects closely monitored to improve the patient's subjective well-being. The important influence of subjective well-being on overall treatment outcome could be underlined.
Responsiveness of quality of life (QOL) assessments in chronic schizophrenic patients was investigated by a quasi-experimental pilot study. Satisfaction ratings were assessed over five time points with an externally imposed disturbing stimulus at the second time point. Despite a markedly high stability, the disturbance provoked a temporally limited decrease in QOL.
To examine the predictive validity of early improvement in a naturalistic sample of inpatients and to identify the criterion that best defines early improvement.
Two hundred and forty-seven inpatients who fulfilled ICD-10 criteria for schizophrenia were assessed with the Positive And Negative Syndrome Scale (PANSS) at admission and at biweekly intervals until discharge from hospital. Remission was defined according to the recently proposed consensus criteria, response as a reduction of at least 40% in the PANNS total score from admission to discharge.
Receiver operating characteristic (ROC) analyses showed that early improvement (reduction of the PANSS total score within the first 2 weeks of treatment) predicts remission (AUC = 0.659) and response (AUC = 0.737) at discharge. A 20% reduction in the PANSS total score within the first 2 weeks was the most accurate cut-off for the prediction of remission (total accuracy: 65%; sensitivity: 53%; specificity: 76%), and a 30% reduction the most accurate cut-off for the prediction of response (total accuracy: 76%; sensitivity: 47%; specificity: 90%).
The findings of clinical drug trials that early improvement is a predictor of subsequent treatment response were replicated in a naturalistic sample. Further studies should examine whether patients without early improvement benefit from an early change of antipsychotic medication.
Repetitive Transcranial Magnetic Stimulation (rTMS) research in psychiatry mostly excludes left-handed participants. We recruited left-handed people with a bulimic disorder and found that stimulation of the left prefrontal cortex may result in different effects in left- and right-handed people. This highlights the importance of handedness and cortex lateralisation for rTMS.
Psychiatric comorbidity is an important aspect of neurological disorders. It affects about 30-50% of neurologic patients but is frequently underrecognized.
Our objective was to determine the prevalence and severity of the symptoms of mental disorders in neurologic in-patients.
Between May and September 2014, all neurologic in-patients of a university neurologic center were asked to complete two self report questionnaires for assessing symptoms of mental disorders, namely the Beck Depression Inventory (BDI) and the Brief Symptom Inventory (BSI), which allow to assess a range of nine different psychiatric domains. We performed a multivariate covariance analysis in order to relate the type and frequency of symptoms of mental disorders with the neurological discharge diagnosis, while age, gender, and duration of in-patient treatment served as putative covariates.
Of all responders (n = 157), 51% stated to have suffered from psychological distress within the past seven days, and 43% indicated depressive symptoms (21% mild, 17% moderate, 5% severe). The mean global severity index GSI (M = 0.64, SD = 0.52) exceeded the 1 SD range of healthy persons but was lower than that of psychiatric in-patients known from the literature. Furthermore, our subanalysis revealed different patterns of symptoms of mental disorders between neurologic patients with degenerative, vascular, demyelinating or epileptic disoders.
Psychometric measurement is useful to characterize the burden of the symptoms of mental disorders and will be used to further develop the psychiatric liaison services.
Social perception is a key aspect of social cognition which has so far not been investigated in eating disorders (ED). This study aimed to investigate social perception in individuals with anorexia nervosa (AN) and bulimia nervosa (BN).
Outpatients with AN (restricting subtype [AN-R]: n = 51; binge-purge subtype [AN-BP]: n = 26) or BN (n = 57) and 50 healthy control (HC) participants completed the Interpersonal Perception Task (IPT-15). This is an ecologically valid task, which consists of 15 video clips, depicting complex social situations relating to intimacy, status, kinship, competition and deception. The participants have to assess relationships between protagonists’ based on non-verbal cues.
Overall, there was no difference between groups on the IPT total score and subscale scores. Group differences on the Intimacy subscale approached significance so post hoc comparisons were carried out. HCs performed significantly better than AN-R participants in determining the degree of intimacy between others.
Social perception is largely preserved in ED patients. Individuals with AN-R show impairments in identifying intimacy in social situations, this may be due to the lack of relationship experience. Further research into different aspects of social cognition is required to establish the link between interpersonal difficulties and ED psychopathology.
Thromboxane (TX) A2 and the activation of its receptor have been shown to modulate vasoconstriction, platelet aggregation, but also dopaminergic and serotonergic signaling.
As dopaminergic and serotonergic systems play a crucial role in the pathophysiology of schizophrenia and as these systems are main targets of antipsychotics, we hypothesized that antipsychotics might also influence TXA2 production.
We measured levels of TXB2, the metabolite of the very unstable molecule TXA2, in the stimulated blood of 10 healthy female subjects in a whole blood assay using the toxic shock syndrome toxin-1 (TSST-1) and the monoclonal antibody against the surface antigen CD3 combined with the protein CD40 (OKT3/CD40) as stimulants. Blood was either supplemented with antipsychotics (chlorpromazine, clozapine, and its metabolite N-desmethylclozapine with four different concentrations each) or not.
Under TSST-1 as well as OKT3/CD40 stimulation, mean TXB2 concentrations were significantly (p < 0.05) decreased by clozapine over all of the applied concentrations. N-desmethylclozapine led to a decrease in TXB2 levels under TSST-1 stimulation only. Chlorpromazine did not show any significant influence on TXB2 production.
Clozapine might, complementary to serotonin and dopamine receptor binding, act on the dopaminergic and serotonergic system via a modulation of TXA2 production. Additionally, side effects of clozapine such as orthostatic hypotension may be a result of the reported TXA2 changes.