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A cumulative environmental exposure score for schizophrenia (exposome score for schizophrenia [ES-SCZ]) may provide potential utility for risk stratification and outcome prediction. Here, we investigated whether ES-SCZ was associated with functioning in patients with schizophrenia spectrum disorder, unaffected siblings, and healthy controls.
This cross-sectional sample consisted of 1,261 patients, 1,282 unaffected siblings, and 1,525 healthy controls. The Global Assessment of Functioning (GAF) scale was used to assess functioning. ES-SCZ was calculated based on our previously validated method. The association between ES-SCZ and the GAF dimensions (symptom and disability) was analyzed by applying regression models in each group (patients, siblings, and controls). Additional models included polygenic risk score for schizophrenia (PRS-SCZ) as a covariate.
ES-SCZ was associated with the GAF dimensions in patients (symptom: B = −1.53, p-value = 0.001; disability: B = −1.44, p-value = 0.001), siblings (symptom: B = −3.07, p-value < 0.001; disability: B = −2.52, p-value < 0.001), and healthy controls (symptom: B = −1.50, p-value < 0.001; disability: B = −1.31, p-value < 0.001). The results remained the same after adjusting for PRS-SCZ. The degree of associations of ES-SCZ with both symptom and disability dimensions were higher in unaffected siblings than in patients and controls. By analyzing an independent dataset (the Genetic Risk and Outcome of Psychosis study), we replicated the results observed in the patient group.
Our findings suggest that ES-SCZ shows promise for enhancing risk prediction and stratification in research practice. From a clinical perspective, ES-SCZ may aid in efforts of clinical characterization, operationalizing transdiagnostic clinical staging models, and personalizing clinical management.
Frogs have been harvested from the wild for the last 40 years in Turkey. We analysed the population dynamics of Anatolian water frogs (Pelophylax spp.) in the Seyhan and Ceyhan Deltas during 2013–2015. We marked a total of 13,811 individuals during 3 years, estimated population sizes, simulated the dynamics of a harvested population over 50 years, and collated frog harvest and export statistics from the region and for Turkey as a whole. Our capture estimates indicated a population reduction of c. 20% per year, and our population modelling showed that, if overharvesting continues at current rates, the harvested populations will decline rapidly. Simulations with a model of harvested population dynamics resulted in a risk of extinction of > 90% within 50 years, with extinction likely in c. 2032. Our interviews with harvesters revealed their economic dependence on the frog harvest. However, our results also showed that reducing harvest rates would not only ensure the viability of these frog populations but would also provide a source of income that is sustainable in the long term. Our study provides insights into the position of Turkey in the ‘extinction domino’ line, in which harvest pressure shifts among countries as frog populations are depleted and harvest bans are effected. We recommend that harvesting of wild frogs should be banned during the mating season, hunting and exporting of frogs < 30 g should be banned, and harvesters should be trained on species knowledge and awareness of regulations.
The relationship between substance use disorders and aggression is complex and not only limited to direct effect of the drugs. Aggression increases the likelihood of substance abuse and is suggested to be a long term individual characteristic which is probably in association with personality traits preexisting before the substance use.
The aim of this study was to evaluate the relationship of personality dimensions with aggression among heroin dependent inpatients and to control the effect of psychiatric symptom severity on this relationship.
Participants were consecutively admitted male heroine (n=78) dependent inpatients. Patients were investigated with the Buss–Perry Aggression Questionnaire (BPAQ), the Temperament and Character Inventory (TCI) and the Symptom Checklist-Revised (SCL-90-R).
Character dimensions self-directedness (SD) and cooperativeness (C) were negatively and self-transcendence (ST) and severity of psychiatric symptoms were positively correlated with severity of aggression and its dimensions. Low SD and C, which are indicative of a personality disorder, were predictors of aggression. Other predictors for aggression in heroin dependents were higher persistence (P) and ST. Severity of psychiatric symptoms predicted aggression together with low C, and high P.
Aggression was more closely related with character dimensions rather than temperament dimensions. Nevertheless, low C and high P predicted the severity of aggression even when the severity of psychopathology was controlled. The careful evaluation of patients for the comorbid psychiatric disorders such as depression, anxiety and personality disorders are needed to handle aggression in heroin dependents which may be related with poor treatment outcome.
Aggression is suggested to be a predictive factor for alcohol use but the casual relationship between aggression and alcohol dependence is complex. Early aggressive acts are a risk factor for early onset alcohol dependence and aggression is suggested to be a long term individual characteristic which is probably in association with personality traits preexisting before the alcohol use.
The aim of this study was to evaluate the relationship of personality dimensions with aggression among alcohol dependent inpatients and to control the effect of psychiatric symptom severity on this relationship.
Participants were consecutively admitted male alcohol (n=94) dependent inpatients. Patients were investigated with the Buss–Perry Aggression Questionnaire (BPAQ), the Temperament and Character Inventory (TCI) and the Symptom Checklist-Revised (SCL-90-R).
Character dimensions self-directedness (SD) and cooperativeness (C) were negatively and severity of psychiatric symptoms was positively correlated with severity of aggression and its dimensions. Low SD and C, which are indicative of a personality disorder, were predictors of aggression. When severity of psychiatric symptoms was included in analyses as an independent variable, it became the main predictor.
Consistent with the hypothesis that aggression is an expression of poor character development, aggression was found to be more closely related with character compared to temperament dimensions. Nevertheless, our findings also suggest that the relationship between the aggression and character dimensions may be indirect through psychopathology. Therefore, when the aggression is the main problem, it is important to evaluate alcohol dependents for the personality dimensions and severity of psychiatric symptoms.
It was suggested that impulsivity is a temperamental risk factor for alcohol use and may be a fundamental mechanism in both the onset of excessive alcohol use and the relapse to alcohol use. Aim of this study was to evaluate the changes in impulsivity scores among alcohol dependents 12 month after inpatient treatment.
Among 78 consecutively admitted male alcohol dependents, 58 were examined by face to face interview 12 months after discharge from hospital. Patients were investigated with the Barratt Impulsiveness Scale, version 11 (BIS-11) (10) both at the baseline and at the end of 12 months.
Among 58 alcohol dependent inpatients 61.8% (n=32) were considered as relapsed to heroin use during 12 month follow-up. Sociodemographic variables did not differ between the groups. Mean impulsivity scores did not differ between remission and relapsed groups at baseline, whereas only non-planning impulsivity was higher in relapsed group at follow-up. Impulsivity score decreased during 12 month follow-up in remission group, whereas increased in relapsed group. Among dimensions of impulsivity non-planning impulsivity decreased in remission group, whereas attentional impulsivity increased.
Results of the present study may suggest that while attentional impulsiveness may be the cause of alcohol use, non-planning impulsiveness may also be a vulnerability factor for alcohol dependency and relapse.
The aim of this study was to evaluate the changes in impulsivity scores among those who are still using buprenorphine as maintenance substitution treatment and those relapsed to heroin use in heroin dependent inpatients at the end of 12 month follow-up. We also controlled depression and trait state anxieties on the relationship between impulsivity and relapse.
Among 78 consecutively admitted male heroin dependents, 52 (66.7%) were examined by face to face interview 12 months after discharge from hospital. Patients were investigated with the Barratt Impulsiveness Scale, version 11 (BIS-11), Beck Depression Inventory and State-Trait Anxiety Inventory at the end of 12 months.
Among 52 heroin dependent patients that were avalible to examine by face to face interview 23 (44.2%) were considered as relapsed to heroin use during the last year, whereas 29 (55.8%) were still in the maintenance treatment. Relapsed group has less attended to polyclinic control, outpatient treatment, they did not change their social environment, continue to see their dependent friends and used other drugs during 12 monts. Mean impulsivity, depression and anxiety scores were higher in the relapsed group. State anxiety and impulsivity, particularly motor impulsivity determined the relapse in regression analyses.
Together with state anxiety, which may be mediated by craving, motor impulsivity predicted relapse. In response to stress or environmental cues, an individual with substance abuse could use the substance in a rapid unplanned action without regard to the consequences.
The aim of the present study was to evaluate relationship of impulsivity with severity of ADHD symptoms while controlling the effects of anxiety and depression in a sample of inpatients with alcohol use disorder.
Participants included 190 inpatients with alcohol use disorder. Participants were evaluated with the State-Trait Anxiety Inventory (STAI), the Beck Depression Inventory (BDI), the Short Form Barratt Impulsiveness Scale (BIS-11-SF) and the Adult ADHD Self-Report Scale (ASRS).
Impulsivity predicted both severity of ADHD symptoms and inattentive and hyperactive/impulsive dimensions, even after controlling the effects of depression and anxiety in linear regression models. Types of negative affect that predicted dimensions of ADHD differed; similar with severity of ADHD symptoms, depression and trait anxiety also predicted inattentive dimension, whereas trait and state anxiety predicted hyperactive/impulsive dimension.
Impulsivity is related with severity of ADHD symptoms and dimensions of ADHD although negative affect that is related with dimensions may differ.
Disclosure of interest
The authors have not supplied their declaration of competing interest.
Obesity is a major public health problem in the world and getting obesity under control is one of the most important goals of the World Health Organization. Cognitive behavioral therapy techniques are helpful for adjusting lifestyle to stay at a healthy weight range. Success of web-based programs which designed with evidence-based behavioral strategies has been proven with different studies. However, a web-based program suitable for Turkish culture and eating habits is still missing.
Primary objective of this project is to develop and test a web-based obesity behavioral treatment program in collaboration with experienced academicians from different disciplines.
The aim of this project is to develop a program which will help Turkish primary care physicians in treating and tracking obesity patients.
The web-based program will include a 12-week-long core behavioral program. Participants will be asked to record their daily dietary intakes and automatic feedback will be given by the system. Weekly behavioral training videos will be available during the core program. As participants watch the videos and record their daily intakes, they will get instant awards such as virtual diet-coin which they will be able to spend for gifts such as low calorie recipes. One hundred obese patients (with body mass index greater than 30 kg/m2) will be recruited to evaluate the effectiveness of the program. The changes in their blood pressures, body weights and waist circumferences will be recorded.
Disclosure of interest
The authors have not supplied their declaration of competing interest.
Turkish version of the UPPS Impulsive Behavior Scale was previously validated in a sample of psychiatric inpatients. The aim of the present study was to evaluate psychometric properties of the sensation seeking subscale of this scale in a sample of inpatients with alcohol use disorder.
Participants (n = 190) were evaluated with the sensation seeking subscale of UPPS Impulsive Behavior Scale.
Sensation seeking subscale had two factors, which together accounted for 63.80% of total variance. As similar with original subscale internal consistency for the sensation seeking (coefficient α=0.859), factor 1 (α=0.862) and factor 2 (α=0.755) examined by Cronbach's alpa, were high. Factor 1 (r = 0.894) and factor 2 (r = 0.863) were highly correlated with total score, whereas moderately correlated (r = 0.544) with each other. Test-retest correlation for sensation seeking (n = 120) was mild (r = 0.460). Test-retest correlation for factor 1 was moderate (r = 0.518) and for factor 2 was mild (r = 0.431).
These findings support the Turkish versions of the sensation seeking subscale of the UPPS has good psychometric properties among inpatients with alcohol use disorder.
Disclosure of interest
The authors have not supplied their declaration of competing interest.
Psychosis spectrum disorder has a complex pathoetiology characterised by interacting environmental and genetic vulnerabilities. The present study aims to investigate the role of gene–environment interaction using aggregate scores of genetic (polygenic risk score for schizophrenia (PRS-SCZ)) and environment liability for schizophrenia (exposome score for schizophrenia (ES-SCZ)) across the psychosis continuum.
The sample consisted of 1699 patients, 1753 unaffected siblings, and 1542 healthy comparison participants. The Structured Interview for Schizotypy-Revised (SIS-R) was administered to analyse scores of total, positive, and negative schizotypy in siblings and healthy comparison participants. The PRS-SCZ was trained using the Psychiatric Genomics Consortiums results and the ES-SCZ was calculated guided by the approach validated in a previous report in the current data set. Regression models were applied to test the independent and joint effects of PRS-SCZ and ES-SCZ (adjusted for age, sex, and ancestry using 10 principal components).
Both genetic and environmental vulnerability were associated with case-control status. Furthermore, there was evidence for additive interaction between binary modes of PRS-SCZ and ES-SCZ (above 75% of the control distribution) increasing the odds for schizophrenia spectrum diagnosis (relative excess risk due to interaction = 6.79, [95% confidential interval (CI) 3.32, 10.26], p < 0.001). Sensitivity analyses using continuous PRS-SCZ and ES-SCZ confirmed gene–environment interaction (relative excess risk due to interaction = 1.80 [95% CI 1.01, 3.32], p = 0.004). In siblings and healthy comparison participants, PRS-SCZ and ES-SCZ were associated with all SIS-R dimensions and evidence was found for an interaction between PRS-SCZ and ES-SCZ on the total (B = 0.006 [95% CI 0.003, 0.009], p < 0.001), positive (B = 0.006 [95% CI, 0.002, 0.009], p = 0.002), and negative (B = 0.006, [95% CI 0.004, 0.009], p < 0.001) schizotypy dimensions.
The interplay between exposome load and schizophrenia genetic liability contributing to psychosis across the spectrum of expression provide further empirical support to the notion of aetiological continuity underlying an extended psychosis phenotype.
Food hubs are of interest in regional and local food system development because they potentially enhance the sustainability of food supply chains. Expanding on earlier literature, this study introduces economies of scale into an aggregation hub location model and disaggregates production into four seasons to account for geographic and seasonal variation of US fresh produce production. A mixed integer linear programming model is formulated with the objective of minimizing total costs of assembly and first-handler operations. Results suggest scale economies have significant effects on the optimal number, locations, and sizes of aggregation hubs. We model regional and local food systems in a manner more consistent with economic theory and provide a richer framework for policy analysis.
We report the size and density of an Egyptian Vulture population in Turkey and provide insight into its nest site selection patterns. The study was carried out at Beypazarı (Turkey), holding one of the densest Egyptian Vulture populations (six pairs per 100 km2) in the Western Palearctic. Random Forests analysis revealed that human impact was a potential factor governing the distribution of nest sites, as the pairs clearly preferred to breed away from nearby villages, towns or roads. Utilisation of elevation gradient and aspect was similar to other studied populations, with the probability of nesting increasing at lower altitudes and for south-facing cliffs. Nearest-neighbour distance between nests was about 1.5 km, indicating territorial behaviour when choosing nest sites at the local scale. Our findings provide guidance for nature conservation NGOs and related government bodies for their various actions including designation of Important Bird Areas, regulation of mining practices and preparation of environmental impact assessments.
The impact of slowly digestible sugars in reducing the risk of developing obesity and related metabolic disorders remains unclear. We hypothesised that such carbohydrates (CHO), resulting in a lower glycaemic and insulinaemic response, may lead to greater postprandial fat oxidation rates in subjects with impaired glucose tolerance (IGT). The present study intends to compare the postprandial metabolic responses to the ingestion of glucose (GLUC) v. trehalose (TRE) and sucrose (SUC) v. isomaltulose (IMU). In a randomised, single-blind, cross-over design, ten overweight IGT subjects were studied four times, following ingestion of different CHO drinks either at breakfast or in combination with a mixed meal at lunch. Before and 3 h after CHO ingestion, energy expenditure, substrate utilisation and circulating metabolite concentrations were determined. Ingestion of CHO drinks with a meal resulted in an attenuated rise in GLUC ( − 33 %) and insulin ( − 14 %) concentrations following TRE when compared with GLUC and following IMU, an attenuation of 43 and 34 % when compared with SUC ingestion, respectively. Additionally, there was less inhibition of the rise in NEFA concentrations and less decline in postprandial fat oxidation (22 %) after IMU when compared with SUC, whereas TRE did not differ from GLUC. The attenuated rise in GLUC and insulin concentrations following IMU ingestion attenuated the postprandial inhibition of fat oxidation compared with SUC when co-ingested with a meal. This suggests that exchange of SUC in the diet for IMU may result in a more favourable metabolic response and may help to reduce the risks associated with obesity and type 2 diabetes.
The impact of slow digestible sources of dietary carbohydrate in reducing the risk of developing obesity and related metabolic disorders is unclear. The aim of the present study was to compare the postprandial metabolic response to the ingestion of sucrose v. isomaltulose. We hypothesised that the reduced digestion and absorption rate of isomaltulose would result in lower glycaemic and insulinaemic responses when compared with the ingestion of sucrose, leading to greater postprandial fat oxidation rates. In a randomised, single-blind, cross-over study, ten overweight subjects ingested two different carbohydrate drinks (sucrose and isomaltulose, 75 g carbohydrate equivalents) following an overnight fast (08.40 hours) and with a standardised meal (12.30 hours, 25 % of total energy content was provided as either a sucrose or isomaltulose drink). Blood samples were taken before ingestion and every 30 min thereafter for a period of 3 h, substrate use was assessed by indirect calorimetry and breath samples were collected. Ingestion of carbohydrates with a mixed meal resulted in a lower peak glucose and insulin response and a lower change in area under the curve (ΔAUC) following isomaltulose when compared with sucrose. Together with the lower glucose and insulin responses, postprandial fat oxidation rates were higher (14 %) with isomaltulose when compared with sucrose when ingested with a mixed meal (P = 0·02). The attenuated rise in glucose and insulin concentrations following isomaltulose results in reduced inhibition of postprandial fat oxidation. The metabolic response to isomaltulose co-ingestion suggests that this may represent an effective nutritional strategy to counteract overweight-induced metabolic disturbances.
The proposed impact of slowly digestible sources of dietary carbohydrate in reducing the risk of developing obesity and related metabolic disorders remains unclear. The aim of the present study was to compare the postprandial metabolic response to the ingestion of glucose v. trehalose. We hypothesised that the reduced digestion and absorption rate of trehalose is accompanied by an attenuated glycaemic and insulinaemic response, leading to a less inhibited postprandial fat oxidation rate. In a randomised, single-blind, cross-over study, ten overweight subjects ingested two carbohydrate drinks (75 g carbohydrate equivalents of trehalose or glucose) following an overnight fast (08.40 hours) and together with a standardised mixed meal (12.30 hours; 25 % total energy content was provided as either glucose or trehalose). Blood samples were collected before ingestion and every 30 min thereafter for a period of 3 h; substrate use was assessed by indirect calorimetry and expired breath samples were collected. Ingestion of carbohydrates with a mixed meal resulted in a lower peak glucose response and a lower change in area under the curve (ΔAUC) following trehalose when compared with glucose. Differences in peak insulin response and ΔAUC were observed with trehalose when compared with glucose during the morning and afternoon. These differences were accompanied with a reduced carbohydrate oxidation after trehalose when ingested as a drink, whilst no significant differences in fat oxidation between drink were observed.
The effect of fertility differences between homogamous and heterogamous matings are considered. The equilibria are evaluated and their stability deterimined. Completely positive and completely negative assortative mating with two and with three forms, are investigated as special cases of the above fertility structure. In these cases convergence of the genotype frequencies has beer demonstrated.
A matrix notation is developed to facilitate study of natural selection in large populations. The processes of mating (taking into account differences between genotypes in fertility in both sexes), segregation, and differential viabilities are each expressed in matrix notation. Assortative mating and non-random segregation can also be described by the method. The separate processes can then be combined to give simple equations relating the genic and genotypic frequencies in one generation to those in the previous generation. This will facilitate computer treatment of natural selection processes.
The method can also be used to study equilibria and the conditions of their stability by examining the latents roots of the matrix. Several special cases of selection at an autosomal locus are examined. The method can be extended to sex-linked loci and two special cases are discussed.
The white-beaked dolphin, Lagenorhynchus albirostris, is commonly found throughout the North Sea and shelf waters of the North Atlantic. Little is known about the behaviour and ecology of this species, especially in British coastal waters. In this paper we present details of the seasonal and geographical distribution of white-beaked dolphins around the UK, along with new information on their diet and habitat use. Analysis of historical stranding records show a segregation of the sexes, with a significant difference between when males and females strand in UK waters. There has been a steady decline in reported strandings since the 1970s and seasonal differences in the distribution of strandings suggest that sea temperature may limit white-beaked dolphin distribution around the British coast. Stomach contents' analysis, from dolphins stranded mainly on the Scottish east coast, identified haddock and whiting as the predominant fish species being taken. Boat surveys were performed along the north-east Scottish coast to examine relationships between topography, environmental conditions, dolphin presence and group size. Dolphin presence was related to seabed slope and aspect while variation in temperature explained almost 45% of variation in observed group size, with smaller groups associated with higher sea temperatures.