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Implicit memories like consumption habits and conditioned reactions to drug-related stimuli are operational in addiction and relapse. The affective startle paradigm is an attractive tool for the measurement of the incentive salience of drug-related cues. We tested whether the stronger appetitive valence of drug cues, shown in two recent startle studies in smokers, does persist after prolonged abstinence, and may thus contribute to relapse.
We examined the auditory startle reflex magnitude of mildly deprived (4-6 hours) heavy smokers (n = 24), former smokers (n = 16, mean abstinence interval 18 months), and non-smokers (n = 24) while they viewed smoking-related scenes or standardized unpleasant, neutral and pleasant control scenes from the International Affective Picture System.
As expected, non-smokers showed no appetitive reactions toward smoking-cues. In smokers, smoking-cues had both appetitive implicit (startle suppression) and explicit (ratings for valence and craving) motivational effects, resembling those of pleasant scenes and differing from neutral and unpleasant scenes. This effect was more pronounced in smokers who later relapsed after a smoking cessation program, and in smokers consuming less than 20 cigarettes per day. Former smokers, despite reporting no craving and negative reactions to smoking cues, still showed evidence of implicit appetitive valence of these cues.
Nicotine addiction results in automatic appetitive reactions to drug-cues, which does not vanish after prolonged abstinence and which may thus contribute to relapses. Heavy smoking may result in a progressive internalization of smoking habits and a decline in reactivity towards external smoking-associated cues.
To assess the differences in comorbid lifetime substance use (tobacco, alcohol and drug use) between eating disorder (ED) patients and healthy controls.
Participants were a consecutive series of 779 ED cases, who had been referred to specialised ED units in five European countries. The ED cases were compared to a balanced control group of 785 healthy individuals. Assessment: Participants completed the Substance Use Subscale of the Cross Cultural Questionnaire (CCQ), a measure of lifetime tobacco, alcohol and drug use. In the control group, also the GHQ-28, the SCID-I interview and the EAT-26 were used.
ED patients had higher lifetime consumption of tobacco and drugs (p <0.01). The only insignificant result was obtained for alcohol (OR= 1.29; δ =0.157; N.S.) and cannabis use (OR= 1.21; δ = 0.037, N.S.). Significant differences across ED sub diagnoses also emerged for all of the assessed variables (p<0.01), with the BN and AN-BP patients generally presenting the highest prevalence rates. The only exception was detected for alcohol consumption where EDNOS patients demonstrated the highest values (p=0.008). Only a few cultural differences between countries emerged (p<0.05).
Lifetime tobacco and drug use but not alcohol consumption are more prevalent in ED patients than healthy controls. While alcohol appears to be more common in EDNOS, smoking and drug use are more frequent in patients with bulimic symptomatology. The differential risk observed in patients with bulimic features might be related to differences in temperament or might be the result of increased sensitivity to reward.
To examine whether there is an association between individual and family eating patterns during childhood and early adolescence and the likelihood of developing an eating disorder (ED) later in life.
Participants were a consecutive series of 879 ED cases from five different European countries. The ED cases were compared to a control group of 785 healthy individuals. Assessment: Participants completed the Early Eating Environmental Subscale of the Cross-Cultural (Environmental) Questionnaire (CCQ), a retrospective measure, which has been developed to detect dimensions associated with EDs in different countries. In the control group, also the GHQ-28, the SCID-I interview and the EAT-26 were used.
Five individual CatPCA procedures revealed five predetermined dimensions which were labeled: 1.) food as individualization; 2.) control and rules about food; 3.) food as social glue; 4.) healthy eating and 5.) food neglect. Logistic regression analyses indicated that the domains with the strongest effects were: food used as individualization (p=0.001; OR=1.76) and control and rules about food (p=0.001; OR=1.76). Conversely, healthy eating was negatively related to a later ED (p=0.001; OR=0.629). The pattern of associated ED factors was found to very between countries. There was very little difference in early eating behavior on the subtypes of the ED.
The fragmentation of meals within the family and control and rules about food appears to be linked to the development of a subsequent ED. On the other hand mantaining a structured and balanced diet during infancy seems to protect from a later ED.
Despite continuing political, legal and moral debate on the subject, assisted suicide is permitted in only a few countries worldwide. However, few studies have examined the impact that witnessing assisted suicide has on the mental health of family members or close friends.
A cross-sectional survey of 85 family members or close friends who were present at an assisted suicide was conducted in December 2007. Full or partial Post-Traumatic Distress Disorder (PTSD; Impact of Event Scale–Revised), depression and anxiety symptoms (Brief Symptom Inventory) and complicated grief (Inventory of Complicated Grief) were assessed at 14 to 24 months post-loss.
Of the 85 participants, 13% met the criteria for full PTSD (cut-off≥35), 6.5% met the criteria for subthreshold PTSD (cut-off≥25), and 4.9% met the criteria for complicated grief. The prevalence of depression was 16%; the prevalence of anxiety was 6%.
A higher prevalence of PTSD and depression was found in the present sample than has been reported for the Swiss population in general. However, the prevalence of complicated grief in the sample was comparable to that reported for the general Swiss population. Therefore, although there seemed to be no complications in the grief process, about 20% of respondents experienced full or subthreshold PTSD related to the loss of a close person through assisted suicide.
Transcranial direct current stimulation (tDCS) is currently investigated for the treatmentof various neuropsychiatric disorders. Neuroplastic effects may be achieved by prolonged neuronal depolarization/hyperpolarization.
Schizophrenia studies revealed a neuroplasticity deficit of cortical areas. Promising results of anodal/cathodal tDCS for acute and chronic symptoms were shown in one randomized clinical trial and several case reports.
To improve negative symptoms, anodal tDCS over the left dorsolateral prefrontal cortex (DLPFC) and cathodal tDCS above the supraorbital region was used. Clinical scores were assessed with Positive and Negative Symptoms Scale (PANSS) and Scale for the Assessment of Negative Symptoms (SANS).
20 patients with predominant negative symptoms and stable medication (>3 weeks) were randomized to active or sham group. Anode was placed over the left DLPFC, cathode over right orbit. 2 mA tDCS was delivered 10 times within weeks 1 and 2. Concomitant medication was continued. Functional connectivity MRI (fcMRI) was performed before and after tDCS.
Post-hoc test (least significant difference, factor ‘group’) showed significant PANSS amelioration in the active group (p = 0.014) for the follow-up, two weeks after the end of stimulation. SANS revealed significant improvement in the active group in week 1 (p = 0.047), week 2 (p = 0.005), and follow-up (p = 0.011). In the active group, fcMRI showed a significant deactivated cluster (corrected p< 0.05) in the anatomical regions of ncl. accumbens, subgenual cortex and striatum.
tDCS is a promising tool to improve various schizophrenic symptoms that are otherwise often difficult to treat.
Over the last decade, the study of functional connectivity networks has dramatically expanded across diverse research fields as functional MRI connectivity (fcMRI) or EEG connectivity. The aim of this study was to evaluate functional connectivity in the course of the day using two different imaging methods.
27 healthy subjects (male and female students in the age-range between 18-30 years) underwent 6 repeated fcMRI measurements over 12 hours in a 3T Philips Achieva MR scanner. The subjects were instructed to close their eyes and not to think on anything in particular. Resting State EEG was recorded outside the MR scanner with eyes closed and eyes open using a Brain MR Amplifier with 32 channels. Sleep deprivation was kept constant across subjects and the subjects were restricted to low-calorie food. EEG was analysed for coherence and EEG-phase between all EEg channels in sensor and source space.
The time course of 20 functional MRI networks were extracted and previous described functional networks were found. Eyes closed and eyes open EEG showed similar and distinct spatial correspondence. We found a good overlap for the Default Mode Network and the Frontal-parietal network. Day of time influenced the EEG measurements partly.
The findings of fcMRI and EEG connectivity are unique with high spatial resolution for fcMRI and high temporal resolution for EEG. Both measurements methods contribute further to our understanding of complex functional connectivity networks.
There is limited information on the presentation and characteristics of psychotic illness experienced by people with autism spectrum disorder (ASD).
To describe autistic and psychotic phenomenology in a group of individuals with comorbid ASD and psychosis (ASD–P) and compare this group with populations affected by either, alone.
We studied 116 individuals with ASD–P. We compared features of their ASD with people with ASD and no comorbid psychosis (ASD–NP), and clinical characteristics of psychosis in ASD–P with people with psychosis only.
Individuals with ASD–P had more diagnoses of atypical psychosis and fewer of schizophrenia compared with individuals with psychosis only. People with ASD–P had fewer stereotyped interests/behaviours compared with those with ASD–NP.
Our data show there may be a specific subtype of ASD linked to comorbid psychosis. The results support findings that psychosis in people with ASD is often atypical, particularly regarding affective disturbance.
The stellar occultation technique is a powerful tool to study distant small solar system bodies. Currently, around 2 500 trans-neptunian objects (TNOs) and Centaurs are known. With the astrometry from Gaia and large surveys like the Large Synoptic Survey Telescope (LSST), accurate predictions of occultation events will be available to tens of thousands of TNOs and Centaurs and boost the knowledge of the outer solar system.
Patients with psychosis display the so-called ‘Jumping to Conclusions’ bias (JTC) – a tendency for hasty decision-making in probabilistic reasoning tasks. So far, only a few studies have evaluated the JTC bias in ‘at-risk mental state’ (ARMS) patients, specifically in ARMS samples fulfilling ‘ultra-high risk’ (UHR) criteria, thus not allowing for comparisons between different ARMS subgroups.
In the framework of the PREVENT (secondary prevention of schizophrenia) study, a JTC task was applied to 188 patients either fulfilling UHR criteria or presenting with cognitive basic symptoms (BS). Similar data were available for 30 healthy control participants matched for age, gender, education and premorbid verbal intelligence. ARMS patients were identified by the Structured Interview for Prodromal Symptoms (SIPS) and the Schizophrenia Proneness Instrument – Adult Version (SPI-A).
The mean number of draws to decision (DTD) significantly differed between ARM -subgroups: UHR patients made significantly less draws to make a decision than ARMS patients with only cognitive BS. Furthermore, UHR patients tended to fulfil behavioural criteria for JTC more often than BS patients. In a secondary analysis, ARMS patients were much hastier in their decision-making than controls. In patients, DTD was moderately associated with positive and negative symptoms as well as disorganization and excitement.
Our data indicate an enhanced JTC bias in the UHR group compared to ARMS patients with only cognitive BS. This underscores the importance of reasoning deficits within cognitive theories of the developing psychosis. Interactions with the liability to psychotic transitions and therapeutic interventions should be unravelled in longitudinal studies.
Altered microbial communities are thought to play an important role in eosinophilic oesophagitis, an allergic inflammatory condition of the oesophagus. Identification of the majority of organisms present in human-associated microbial communities is feasible with the advent of high throughput sequencing technology. However, these data consist of non-negative, highly skewed sequence counts with a large proportion of zeros. In addition, hierarchical study designs are often performed with repeated measurements or multiple samples collected from the same subject, thus requiring approaches to account for within-subject variation, yet only a small number of microbiota studies have applied hierarchical regression models. In this paper, we describe and illustrate the use of a hierarchical regression-based approach to evaluate multiple factors for a small number of organisms individually. More specifically, the zero-inflated negative binomial mixed model with random effects in both the count and zero-inflated parts is applied to evaluate associations with disease state while adjusting for potential confounders for two organisms of interest from a study of human microbiota sequence data in oesophagitis.
Africa is experiencing a rapid increase in adult obesity and associated cardiometabolic diseases (CMDs). The H3Africa AWI-Gen Collaborative Centre was established to examine genomic and environmental factors that influence body composition, body fat distribution and CMD risk, with the aim to provide insights towards effective treatment and intervention strategies. It provides a research platform of over 10 500 participants, 40–60 years old, from Burkina Faso, Ghana, Kenya and South Africa. Following a process that involved community engagement, training of project staff and participant informed consent, participants were administered detailed questionnaires, anthropometric measurements were taken and biospecimens collected. This generated a wealth of demographic, health history, environmental, behavioural and biomarker data. The H3Africa SNP array will be used for genome-wide association studies. AWI-Gen is building capacity to perform large epidemiological, genomic and epigenomic studies across several African counties and strives to become a valuable resource for research collaborations in Africa.
Summary studies of dairy cow removal indicate increasing levels of mortality over the past several decades. This poses a serious problem for the US dairy industry. The objective of this project was to evaluate associations between facilities, herd management practices, disease occurrence and death rates on US dairy operations through an analysis of the National Animal Health Monitoring System’s Dairy 2007 survey. The survey included farms in 17 states that represented 79.5% of US dairy operations and 82.5% of the US dairy cow population. During the first phase of the study operations were randomly selected from a sampling list maintained by the National Agricultural Statistics Service. Only farms that participated in phase I and had 30 or more dairy cows were eligible to participate in phase II. In total, 459 farms had complete data for all selected variables and were included in this analysis. Univariable associations between dairy cow mortality and 162 a priori identified operation-level management practices or characteristics were evaluated. Sixty of the 162 management factors explored in the univariate analysis met initial screening criteria and were further evaluated in a multivariable model exploring more complex relationships. The final weighted, negative binomial regression model included six variables. Based on the incidence rate ratio, this model predicted 32.0% less mortality for operations that vaccinated heifers for at least one of the following: bovine viral diarrhea, infectious bovine rhinotracheitis, parainfluenza 3, bovine respiratory syncytial virus, Haemophilus somnus, leptospirosis, Salmonella, Escherichia coli or clostridia. The final multivariable model also predicted a 27.0% increase in mortality for operations from which a bulk tank milk sample tested ELISA positive for bovine leukosis virus. Additionally, an 18.0% higher mortality was predicted for operations that used necropsies to determine the cause of death for some proportion of dead dairy cows. The final model also predicted that increased proportions of dairy cows with clinical mastitis and infertility problems were associated with increased mortality. Finally, an increase in mortality was predicted to be associated with an increase in the proportion of lame or injured permanently removed dairy cows. In general terms, this model identified that mortality was associated with reproductive problems, non-infectious postpartum disease, infectious disease and infectious disease prevention, and information derived from postmortem evaluations. Ultimately, addressing excessive mortality levels requires a concerted effort that recognizes and appropriately manages the numerous and diverse underlying risks.
We aimed to assess whether the characteristics of influenza-like illness (ILI) cases in the general population were similar during the seasonal and pandemic A(H1N1)pdm09 influenza periods. We conducted a study using a general population database, which included demographic (sex, age) and clinical (underlying medical conditions, influenza vaccination status) information on more than 80 000 subjects. We assessed the most important predictors of ILI during each season by using multiple logistic regression. We descriptively compared whether they were similar during different seasons. The model, including all demographic and clinical characteristics, showed that age ⩾60 years decreased the odds for ILI by 52% and 81% during the seasonal and A(H1N1)pdm09 pandemic periods, respectively. Being vaccinated decreased the odds of ILI for seasonal influenza by 32%, while suffering from the comorbidities other than lung or cardiovascular diseases doubled the odds of ILI during the A(H1N1)pdm09 pandemic.
As physical activity may modify the effect of the apolipoprotein E (APOE) ε4 allele on the risk of dementia and Alzheimer's disease (AD) dementia, we tested for such a gene–environment interaction in a sample of general practice patients aged ⩾75 years.
Data were derived from follow-up waves I–IV of the longitudinal German study on Ageing, Cognition and Dementia in Primary Care Patients (AgeCoDe). The Kaplan–Meier survival method was used to estimate dementia- and AD-free survival times. Multivariable Cox regression was used to assess individual associations of APOE ε4 and physical activity with risk for dementia and AD, controlling for covariates. We tested for gene–environment interaction by calculating three indices of additive interaction.
Among the randomly selected sample of 6619 patients, 3327 (50.3%) individuals participated in the study at baseline and 2810 (42.5%) at follow-up I. Of the 2492 patients without dementia included at follow-up I, 278 developed dementia (184 AD) over the subsequent follow-up interval of 4.5 years. The presence of the APOE ε4 allele significantly increased and higher physical activity significantly decreased risk for dementia and AD. The co-presence of APOE ε4 with low physical activity was associated with higher risk for dementia and AD and shorter dementia- and AD-free survival time than the presence of APOE ε4 or low physical activity alone. Indices of interaction indicated no significant interaction between low physical activity and the APOE ε4 allele for general dementia risk, but a possible additive interaction for AD risk.
Physical activity even in late life may be effective in reducing conversion to dementia and AD or in delaying the onset of clinical manifestations. APOE ε4 carriers may particularly benefit from increasing physical activity with regard to their risk for AD.
Whether late-onset depression is a risk factor for or a prodrome of dementia remains unclear. We investigated the impact of depressive symptoms and early- v. late-onset depression on subsequent dementia in a cohort of elderly general-practitioner patients (n = 2663, mean age = 81.2 years).
Risk for subsequent dementia was estimated over three follow-ups (each 18 months apart) depending on history of depression, particularly age of depression onset, and current depressive symptoms using proportional hazard models. We also examined the additive prediction of incident dementia by depression beyond cognitive impairment.
An increase of dementia risk for higher age cut-offs of late-onset depression was found. In analyses controlling for age, sex, education, and apolipoprotein E4 genotype, we found that very late-onset depression (aged ⩾70 years) and current depressive symptoms separately predicted all-cause dementia. Combined very late-onset depression with current depressive symptoms was specifically predictive for later Alzheimer's disease (AD; adjusted hazard ratio 5.48, 95% confidence interval 2.41–12.46, p < 0.001). This association was still significant after controlling for cognitive measures, but further analyses suggested that it was mediated by subjective memory impairment with worries.
Depression might be a prodrome of AD but not of dementia of other aetiology as very late-onset depression in combination with current depressive symptoms, possibly emerging as a consequence of subjectively perceived worrisome cognitive deterioration, was most predictive. As depression parameters and subjective memory impairment predicted AD independently of objective cognition, clinicians should take this into account.
An energy resource is the first step in the chain that supplies energy services (for a definition of energy services, see Chapter 1). Energy services are largely ignorant of the particular resource that supplies them; however, often the infrastructures, technologies, and fuels along the delivery chain are highly dependent on a particular type of resource. The availability and costs of bringing energy resources to the market place are key determinants to affordable and accessible energy services.
Energy resources pose no inherent limitation to meeting the rapidly growing global energy demand as long as adequate upstream investment is forthcoming – for exhaustible resources in exploration, production technology, and capacity (mining and field development) and, by analogy, for renewables in conversion technologies.
Hydrocarbons and Nuclear
Occurrences of hydrocarbons and fissile materials in the Earth's crust are plentiful – yet they are finite. The extent of the ultimately recoverable oil, natural gas, coal, or uranium is the subject of numerous reviews, yet still the range of values in the literature is large (Table 7.1). For example, the range for conventional oil is between 4900 exajoules (EJ) for reserves to 13,700 EJ (reserves plus resources) – a range that sustains continued debate and controversy. The large range is the result of varying boundaries of what is included in the analysis of a finite stock of an exhaustible resource, e.g., conventional oil only or conventional oil plus unconventional occurrences, such as oil shale, tar sands, and extra-heavy oils.