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Background: PET imaging of [11C]ABP688 shows reduced hippocampal mGluR5 availability in mesial temporal lobe epilepsy (MTLE) patients, however the relation with post-surgical outcomes is unclear. Here, we tested whether [11C]ABP688 binding in hippocampal subfields vulnerable to glutamate excitotoxicity is related to post-surgical outcome. Methods: [11C]ABP688-PET was obtained from 31 unilateral MTLE patients and 30 controls. Hippocampal subfields were automatically segmented into 1) CA1-3, 2) CA4/dentate gyrus (DG), 3) Subiculum and manually corrected. Partial volume corrected [11C]ABP688 non-displaceable binding potential (BPND) was calculated in the subfields and compared between seizure-free and non-seizure-free patients. Results: [11C]ABP688 BPND was significantly reduced in ipsilateral CA1-3 & CA4/DG (p<0.001) compared to controls. No difference was seen in Subiculum. Ipsilateral CA1-3 [11C]ABP688 BPND was lower in seizure-free (p=0.012; Engel Ia, n=13) vs non-seizure- free (Engel Ic-III, n=10) patients, and this effect was independent of subfield volume. In a subset of patients with [18F]FDG-PET, CA1-3 [11C]ABP688 BPND was significantly lower in seizure-free patients (p=0.03), while no difference was found for [18F]FDG uptake. Conclusions: Reduced CA1-3 mGluR5 availability was associated with post-surgical seizure-freedom independent of atrophy and hypometabolism. Thus, [11C]ABP688-PET may offer a potential biomarker for surgical outcomes and may be particularly relevant for pre-surgical workup in MRI- and [18F]FDG-negative MTLE patients.
Companies offer products in different variants to reach more customers. This increases internal variety and cost. However, reducing those cost is difficult due to complexity. Complexity arises from: combinatorics; many design variables interacting with each other; coupling of technical and economical perspectives. This paper presents an approach based on (1) building a complex system model of modular models; (2) identifying the potential for standardization from a technical perspective; (3) cost-optimizing the degree of standardization. A product family of electric vehicles was optimized.
Complexity in systems design can be reduced by computing permissible ranges for some crucial design variables that need to be defined in an early design phase. These ranges are calculated such that there is sufficient tolerance for the remaining design variables in later design phases, while still achieving the overall system design goals. A new algorithm for this approach is presented and applied to the design of a vehicle powertrain mount system. The results show large permissible ranges for mount positions while maintaining sufficient tolerance for mount stiffnesses.
A reason for the slow adoption of digital twins in industry is a lack of trust in the concept and between the stakeholders involved. This paper presents a Trust Framework for Digital Twins based on a literature review and an interview study, including seven recommendations: (1) explain your twin, (2) create a common incentive, (3) make only one step at a time, (4) ensure IP protection and IT security, (5) prove your quality, (6) ensure a uniform environment, and (7) document thoroughly. Together with 20 concrete measures it supports practitioners in improving trust in their Digital Twin.
A digital twin (DT) relies on a detailed, virtual representation of a physical product. Since uncertainties and deviations can lead to significant changes in the functionality and quality of products, they should be considered in the DT. However, valuable product properties are often hidden and thus difficult to integrate into a DT. In this work, a Bayesian inverse approach based on surrogate models is applied to infer hidden composite laminate ply angles from strain measurements. The approach is able to find the true values even for ill-posed problems and shows good results up to 6 plies.
Collaboration is common practice within design disciplines and beyond. Brainstorming, discussions, and prototyping tend to occur within the same physical space. The reduction of human interaction during the COVID-19 pandemic disrupted these practices. In this paper, we focus on the possibilities and challenges of remote prototyping of four student teams by combining a double diamond approach with tools to overcome remote work challenges. The results were analyzed to understand crucial tools, advantages, and obstacles. The key challenges and opportunities were then identified and examined.
In top-down design, optimal component requirements are difficult to derive, as the feasible components that satisfy these requirements are yet to be designed and hence unknown. Meta models that provide feasibility and mass estimates for component performance are used for optimal requirement decomposition in an existing approach. This paper (1) extends its applicability adapting it to varying design domains, and (2) increases its efficiency by active-learning. Applying it to the design of a robot arm produces a result that is 1% heavier than the reference obtained by monolithic optimization.
The design of service robots is typically treated as a mechatronic design problem aimed at implementation of its core technical functionalities. Intuitive operation and usability are ignored. We developed a trash-picking service robot with a strong focus on human-robot interaction (HRI) using the double diamond framework. The HRI-focussed hardware features were successfully implemented and tested. The results were shown to satisfy the ease of operation and usability requirements set as development goals for the robot.
Background: PET imaging of [11C]ABP688 shows reduced hippocampal mGluR5 availability in mesial temporal lobe epilepsy (MTLE) patients, however the relation with post-surgical outcomes is unclear. Here, we tested whether [11C]ABP688 binding in hippocampal subfields vulnerable to glutamate excitotoxicity is related to post-surgical outcome. Methods: [11C]ABP688-PET was obtained from 31 unilateral MTLE patients and 30 controls. Hippocampal subfields were automatically segmented into 1) CA1-3, 2) CA4/dentate gyrus (DG), and 3) Subiculum and manually corrected. Partial volume corrected [11C]ABP688 non-displaceable binding potential (BPND) was calculated in the subfields and compared between seizure-free and non-seizure-free patients. Results: [11C]ABP688 BPND was significantly reduced in ipsilateral CA1-3 & CA4/DG (p<0.001) compared to controls. No difference was seen in Subiculum. Ipsilateral CA1-3 [11C]ABP688 BPND was lower in seizure-free (p=0.012; Engel Ia, n=13) vs non-seizure-free (Engel Ic-III, n=10) patients, and this effect was independent of subfield volume. In a subset of patients with [18F]FDG-PET, CA1-3 [11C]ABP688 BPND was significantly lower in seizure-free patients (p=0.03), while no difference was found for [18F]FDG uptake. Conclusions: Reduced CA1-3 mGluR5 availability was associated with post-surgical seizure-freedom independent of atrophy and hypometabolism. Thus, [11C]ABP688-PET may offer a potential biomarker for surgical outcomes and may be particularly relevant for pre-surgical workup in MRI- and [18F]FDG-negative MTLE patients.
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.
John Rawls (1921–2002) and his work are now squarely a subject for history. In the more than fifteen years since his death, a rich body of scholarship has emerged which attempts, in different ways, to understand the nature, development, and impact of Rawls's thought from a variety of historical perspectives. With 2021 marking fifty years since A Theory of Justice (1971) was first published, this special forum examines what we here call the “historical Rawls.”
As current vehicle development processes in the automotive industry are highly distributed, the interaction between design teams is limited. In this paper we use a simulation in order to investigate how the rate of design team interaction affects the solution quality and development cost. Results show, that in case of no limiting constraints, a low rate of interaction yields the best results regarding solution quality and development cost. If design activities are affected by constraints, however, the rate of interaction is subject to a conflict between solution quality and development cost.
Maximizing the number of shared components does not always produce cost-optimal product families. Shared components can yield economies of scale due to reuse of components, but also increases material cost due to over dimensioning. In this paper, we present an approach to identify a cost-optimal design for product families. It consists of two steps: (1) identifying a scheme to share components in the product family and (2) finding the cost optimal design for the product family.
A Digital Twin as a virtual representation of a physical system is becoming a key technology. While potential benefits are evident, there is no approach in literature or practice comprehensively supporting its introduction. In an industrial case study, a generic procedure model for the conception and implementation of a Digital Twin was developed. The relations between use cases, usage data, and virtual models resulted in a target concept as well as requirements for the implementation. Thereby, companies can access the potentials of a Digital Twin taking into account their specific situation.
Over the last two decades, a concept called Digital Twin has evolved rapidly. Yet, there is no unified definition of the term. Based on a literature study and an industrial case study, an overarching definition of Digital twins is presented. Three characteristics were identified – representation of a physical system, bidirectional data exchange, and the connection along the entire lifecycle. Further, three sub-concepts are presented, namely: Engineering Twin, Production Twin, and Operation Twin. The presented paper thus formulates a consistent and detailed definition of Digital Twins.
Despite significant advances, early detection and intervention regarding psychosis still face major obstacles. The Basel FePsy-study tries to contribute to optimising the methods for assessment of risk for psychosis, by describing individuals in an At Risk Mental State (ARMS) with and without later transition to psychosis as compared to healthy (HC) and depressive controls (DC) and by using a multidomain approach including not only psychopathology and clinical risk factors, but also neuropsychology, neurophysiology and neuroimaging.
60 ARMS subjects, 51 HC and 34 DC were investigated. 53 ARMS individuals could be followed up for up to 7 years.
21 ARMS individuals made the transition to psychosis (transition rate 34%). As compared to HC, they showed significant deficits in executive functions and working memory. Predictors of transition were certain attenuated psychotic and negative symptoms and certain cognitive deficits. In an integrated model for prediction of transition using these variables, the overall predictive accuracy was 80.9%, with a sensitivity of 83.3% and a specificity of 79.3%. Specificity of prediction could be further improved by EEG analysis. Furthermore, MRI showed specific differences between ARMS with and without later transition to psychosis.
Individuals at risk for psychosis do not only show psychopathological prodromes and social decline, but also neuropsychological impairments and EEG- as well as MRI-abnormalities. Hopefully in the near future, a clinical staging of individuals according to their risk for psychosis will be possible with corresponding stepwise early interventions.
Albumin is a protein which serves as a transporter for a variety of metabolites and as a storage for a lot of substances. Although albumin cannot pass the blood-brain-barrier and thus influence the CNS directly, a negative relation between cognitive impairment and serum albumin level has been observed in studies of normal and pathological aging.
The aim of the present study was to investigate the association between albumin and social cognition in ADHD.
20 adult patients with ADHD and 20 healthy controls participated in a double-blind within subjects crossover study. Participants completed the Moral-Judgment-Test, Tuebingen Affect Battery, the Movie for the Assessment of Social Cognition (MASC) and Cambridge Behaviour Scale (EQ). In addition, ADHD symptoms were assessed by the Wender Utah Rating Scale (WURS-K) and ADHD Self Rating Scale. Serum albumin levels were determined after blood withdrawal.
In the patient group serum albumin levels were negatively associated with ADHD pathology measured by WURS-K. In addition, a low level of albumin was related with poorer performance in theory of mind, moral judgment competence and affective prosody tasks.
The results suggest that albumin is related to social cognition in younger patients with ADHD. This is, to the knowledge of the authors, the first investigation, in which the association between albumin and cognition has been investigated in ADHD. Thus the findings of the present study need replication and the neural mechanisms have to be explored in future studies. Further studies are needed to exclude a possible medication effect.
This study assessed the underexplored factors associated with significant improvement in mothers’ mental health during postpartum inpatient psychiatric care.
This study analyzed clinical improvement in a prospective cohort of 869 women jointly admitted with their infant to 13 psychiatric Mother-Baby Units (MBUs) in France between 2001 and 2007. Predictive variables tested were: maternal mental illness (ICD-10), sociodemographic characteristics, mental illness and childhood abuse history, acute or chronic disorder, pregnancy and birth data, characteristics and mental health of the mother's partner, and MBU characteristics.
Two thirds of the women improved significantly by discharge. Admission for 25% was for a first acute episode very early after childbirth. Independent factors associated with marked improvement at discharge were bipolar or depressive disorder, a first acute episode or relapse of such an episode. Schizophrenia, a personality disorder, and poor social integration (as measured by occupational status) were all related to poor clinical outcomes.
Most women improved significantly while under care in MBUs. Our results emphasize the importance of the type of disease but also its chronicity and the social integration when providing postpartum psychiatric care.
Attention deficit disorder (ADHD) is a psychiatric disorder, which is characterized by deficits of executive functions (EF) and impulsivity. Whereas a variety of studies on the involvement of the dopaminergic system in ADHD exists, the impact of the serotonergic system to EF in ADHD in adults is underinvestigated.
To ascertain the effects of rapid tryptophan depletion (RTD) and the resultant reduction of the central nervous levels of serotonin on the EF of male adult patients with ADHD.
20 ADHD patients and 20 healthy controls completed the RTD test on one day and a placebo on another day in a double-blind within subject crossover design.- In addition, the subtest alertness of the TAP and a modified Version of the Continuous performance test (AX-CPT) with three stimulus conditions (AX, AY, BX) were administered.
Statistical analysis revealed significant shorter reaction times, more errors and more omission errors in the ADHD group in the AX-CPT. The omissions error rate increased in both groups in the RTD condition but not in the placebo condition. Statistical analyses did not yield any significant differences between groups in the subtest alertness and no significant interaction of group and effect of the RTD condition could be observed.
In addition to higher impulsivity of patients with ADHD as reflected by shorter reaction times and higher error rates, the results of the present study imply an involvement of the serotonergic system as reflected by RTD in sustained and selective attention.