RandD Unit

Firenze, Italy

RandD Unit

Firenze, Italy
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Rizzi M.,Polytechnic of Milan | Ciocchini N.,Polytechnic of Milan | Montefiori A.,University of Milan Bicocca | Ferro M.,RandD Unit | And 3 more authors.
Technical Digest - International Electron Devices Meeting, IEDM | Year: 2013

Introduction: Recently, phase change memory (PCM) has entered the commercial stage in a 45 nm technology [1]. To better assess the potential scaling and application as embedded memory [2], data retention and its statistics must be carefully understood and optimized. This work studies crystallization statistics in 1 Gb arrays of PCM devices. We evidence (i) retention stabilization by tuning of the programming conditions, and (ii) erratic retention due to crystallization variability. A new retention model is developed, which is capable of predicting cell-to-cell and cycle-to-cycle variability as a function of programming conditions. © 2013 IEEE.


Lindwall M.,Gothenburg University | Ljung T.,Mid Sweden University | Ljung T.,RandD unit | Hadzibajramovic E.,Institute of Stress Medicine | And 2 more authors.
Mental Health and Physical Activity | Year: 2012

Background: A relevant, but overlooked question is if self-reported physical activity and aerobic fitness are differently related to mental health. Purpose: To examine the relation between mental health and level of self-reported physical activity (SRPA) and aerobic fitness (AF), and whether AF mediates the relation between SRPA and mental health. Methods: Participating in the study were 177 voluntary subjects (49% men, 51% women) with a mean age of 39 years. Symptoms of depression and anxiety were measured through the Hospital Anxiety and Depression (HAD) scale, and the Shirom-Melamed Burnout Questionnaire (SMBQ) was used to evaluate self-reported symptoms of burnout. Leisure time SRPA during the last three months were measured using a single item. AF was measured by using the Åstrand bicycle test. Results: Self-reported physical activity, but not AF, was significantly related to self-reported symptoms of depression, anxiety, and burnout. Light to moderate physical activity that is performed regularly seems to be associated with more favorable mental health pattern compared with physical inactivity. No support was found for the mediating effect of AF of the physical activity-mental health relationship. Conclusions: Self-reported behavior of regular physical activity seems to be more important to monitor than measures of AF when considering the potential preventive effects of physical activity on mental health. © 2012 Elsevier Ltd. All rights reserved.


Rastam M.,Lund University | Taljemark J.,Lund University | Tajnia A.,Gothenburg University | Lundstrom S.,Gothenburg University | And 7 more authors.
The Scientific World Journal | Year: 2013

Aim. To establish the prevalence of restrictive eating problems, the overlap and association with attention-deficit/hyperactivity disorder (ADHD), and autism spectrum disorders (ASD) and to estimate the heritability of eating problems in a general population sample of twins aged 9 and 12. Methods. Parents of all Swedish 9- and 12-year-old twin pairs born between 1993 and 1998 (n = 12,366) were interviewed regarding symptoms of ADHD, ASD, and eating problems (EAT-P). Intraclass correlations and structural equation modelling were used for evaluating the influence of genetic and environmental factors. Cross-twin, cross-trait correlations were used to indicate a possible overlap between conditions. Results. The prevalence of eating problems was 0.6% in the study population and was significantly higher in children with ADHD and/or ASD. Among children with eating problems, 40% were screened positive for ADHD and/or ASD. Social interaction problems were strongly associated with EAT-P in girls, and impulsivity and activity problems with EAT-P in boys. The cross-twin, cross-trait correlations suggested low correlations between EAT-P and ADHD or EAT-P and ASD. Genetic effects accounted for 44% of the variation in liability for eating problems. Conclusions. In the group with eating problems, there was a clear overrepresentation of individuals with ADHD and/or ASD symptoms. © 2013 Maria Råstam et al.


Jonsson L.,Gothenburg University | Zettergren A.,Gothenburg University | Pettersson E.,Karolinska Institutet | Hovey D.,Gothenburg University | And 6 more authors.
Molecular Autism | Year: 2014

Background: Autistic-like traits (ALTs) are continuously distributed in the general population, with the autism spectrum disorder (ASD) at the upper extreme end. A genetic overlap has been shown between ALTs and ASD, indicating that common variation in ASD candidate genes may also influence ALTs. In our study, we have investigated the SNP rs4307059 that has been associated with both ALTs and ASD. In addition, we genotyped polymorphisms in a selection of genes involved in synaptic functioning, that is, SHANK3, RELN, and CNTNAP2, which repeatedly have been associated with ASD. The possible associations of these polymorphisms with ALTs, as well as genetic factors for neurodevelopmental problems (NDPs), were investigated in a large cohort from the general population: The Child and Adolescent Twin Study in Sweden. For analyses of ALTs and NDPs, 12,319 subjects (including 2,268 monozygotic (MZ) and 3,805 dizygotic (DZ) twin pairs) and 8,671 subjects (including 2,243 MZ and 2,044 DZ twin pairs), respectively, were included in the analyses. Findings: We could not replicate the previous association between rs4307059 and social communication impairment. Moreover, common variations in CNTNAP2 (rs7794745 and rs2710102), RELN (rs362691), and SHANK3 (rs9616915) were not significantly associated with ALTs in our study. Conclusions: Our results do not suggest that the investigated genes, which previously has been found associated with ASD diagnosis, have any major influence on ALTs in children from the general population. © 2014 Jonsson et al.


Magnusson P.K.E.,Karolinska Institutet | Almqvist C.,Karolinska Institutet | Almqvist C.,Childrens Health and Astrid Lindgren Childrens Hospital | Rahman I.,Karolinska Institutet | And 22 more authors.
Twin Research and Human Genetics | Year: 2013

The Swedish Twin Registry (STR) today contains more than 194,000 twins and more than 75,000 pairs have zygosity determined by an intra-pair similarity algorithm, DNA, or by being of opposite sex.Of these, approximately 20,000, 25,000, and 30,000 pairs are monozygotic, same-sex dizygotic, and opposite-sex dizygotic pairs, respectively.Since its establishment in the late 1950s, the STR has been an important epidemiological resource for the study of genetic and environmental influences on a multitude of traits, behaviors, and diseases.Following large investments in the collection of biological specimens in the past 10 years we have now established a Swedish twin biobank with DNA from 45,000 twins and blood serum from 15,000 twins, which effectively has also transformed the registry into a powerful resource for molecular studies.We here describe the main projects within which the new collections of both biological samples as well as phenotypic measures have been collected.Coverage by year of birth, zygosity determination, ethnic heterogeneity, and influences of in vitro fertilization are also described.Copyright © The Authors 2012.


Jonsson L.,Gothenburg University | Anckarsater H.,Sahlgrenska Academy | Zettergren A.,Gothenburg University | Westberg L.,Gothenburg University | And 7 more authors.
Psychiatric Genetics | Year: 2014

Individuals with autism spectrum disorders often show low levels of melatonin, and it has been suggested that this decrease may be because of the low activity of the acetylserotonin O-methyltransferase (ASMT), the last enzyme in the melatonin-synthesis pathway. Also, genetic variants in ASMT have been associated with autism, as well as with low ASMT activity and melatonin levels, suggesting that the low ASMT activity observed in autism may partly be because of variations within the ASMT gene. In this study, we present a symptom-based approach to investigate possible associations between ASMT and autistic-like traits in the general population. To this end, continuous measures of autistic-like traits were assessed in a nationally representative twin cohort (n=1771) from Sweden and six single nucleotide polymorphisms (SNPs), and a duplication of exons 2-8 in ASMT were genotyped. Our results show a nominally significant association, in girls, between one single nucleotide polymorphism (rs5949028) in the last intron of ASMT and social interaction impairments. No significant association, however, was observed with traits related to language impairment or restricted and repetitive behavior. In conclusion, our results support the possible involvement of the ASMT gene in autism spectrum disorders, and our finding that only one of the three traits shows association suggests that genetic research may benefit from adopting a symptom-specific approach to identify genes involved in autism psychopathology. © 2014 Wolters Kluwer Health | Lippincott Williams & Wilkins.


Lundstrom S.,Gothenburg University | Lundstrom S.,RandD Unit | Reichenberg A.,Mount Sinai School of Medicine | Melke J.,Gothenburg University | And 6 more authors.
Journal of Child Psychology and Psychiatry and Allied Disciplines | Year: 2015

Background Evidence from twin and molecular genetic studies is accumulating that Autism Spectrum Disorder (ASD) shares substantial etiological factors with other disorders. This is mirrored in clinical practice where ASD without coexisting disorders is rare. The present study aims to examine the range of coexisting disorders in ASD in a genetically informative cohort. Methods Parents of all Swedish 9-year-old twins born between 1992 and 2001 (n = 19,130) underwent a telephone interview designed to screen for child psychiatric disorders, including ASD. To ensure full coverage of child psychiatric disorders, data were also retrieved from population-based health registers. We investigated the coexistence of eight psychiatric disorders known to coexist with ASDs in probands and their co-twins. Results Half of the individuals with ASDs (50.3%) had four or more coexisting disorders and only 4% did not have any concomitant disorder. The 'healthy co-twin' in ASD discordant monozygotic twin pairs was very often (79% of boys and 50% of girls) affected by at least one non-ASD disorder. The corresponding figures for ASD discordant dizygotic twin pairs were significantly lower (46% of males and 30% of females). Conclusions Detailed phenotypic descriptions including symptoms of problems associated with a wide range of child psychiatric disorders may aid in unraveling the genetic architecture of ASD and should guide the development of intervention strategies addressing each problem type specifically. © 2014 Association for Child and Adolescent Mental Health.


Akesson E.,Karolinska Institutet | Akesson E.,RandD Unit | Calzarossa C.,Karolinska Institutet | Sundstrom E.,Karolinska Institutet | Sundstrom E.,RandD Unit
Neuromethods | Year: 2013

Animal models are indispensable for research on central nervous system disorders and particularly relevant and useful in spinal cord injury (SCI) research. In contrast to neurodegenerative diseases, trauma inflicted to animals is inherently similar (albeit not identical) to the situation after trauma in human beings. There are still many factors to consider when the choice of animal model is to be made. How should the injury be induced? At what segmental level? Which parameters can be evaluated? Ultimately, the purpose of the study should be defined before an animal model is chosen. Assessing acute and chronic structural changes, studying motor and sensory functions after injury, and evaluating treatments such as protective drugs or substances enhancing regeneration all place different demands on the animal model and how results from the model are interpreted. With a focus on small animal (rodent) models of SCI, we give a background on pathology and pathophysiology, review the most common rodent injury models and functional tests used, present examples of experimental studies using various methods, and discuss difficulties in translating results from animal models to the clinical situation. © 2013 Springer Science+Business Media, LLC.


Garcia D.,Gothenburg University | Anckarsater H.,Gothenburg University | Anckarsater H.,Lund University | Lundstrom S.,Gothenburg University | Lundstrom S.,RandD Unit
The Scientific World Journal | Year: 2013

Background. The acronym ESSENCE (Early Symptomatic Syndromes Eliciting Neurodevelopmental Clinical Examinations) highlights that children seeking clinical treatment are often multiply impaired, thus requiring treatment from several specialties. The aim was to map and relate, on a population level, ESSENCE to two salient predictors of health and adaptation to adversities, namely, Self-Directedness and Cooperativeness and also to dysfunction and suffering. Methods. Participants were twins (N = 1892) aged 9 or 12 whose parents were interviewed with the Autism-Tics, ADHD and other Comorbidities inventory (A-TAC), and the Junior Temperament and Character Inventory (J-TCI). The A-TAC was first used to discern four ESSENCE-related screening diagnoses: autism spectrum disorders, attention deficit hyperactivity disorder, learning disabilities, and developmental coordination disorder; second, to quantify dysfunction and suffering in important social areas. Results. ESSENCE symptoms were continuously and categorically associated with deficiency in Self-Directedness and Cooperativeness and higher ratings of dysfunction and suffering. The impact of ESSENCE symptoms on these measures of mental health was found in a milder form in about 16% of all children and in a severe form in about 2%. Conclusion. Therapeutic interventions focusing on Self-Directedness and Cooperativeness might provide a novel method for child psychiatry in its approach to ESSENCE. © 2013 Danilo Garcia et al.


Garcia D.,Gothenburg University | Kerekes N.,Gothenburg University | Kerekes N.,RandD Unit | Andersson Arnten A.-C.,Gothenburg University | Archer T.,Gothenburg University
Depression Research and Treatment | Year: 2012

Positive (PA) and negative affect (NA) are two separate systems markers of subjective well-being and measures of the state depression (low PA combined with high NA). The present study investigated differences in temperament, character, locus of control, and depressive symptoms (sleep quality, stress, and lack of energy) between affective profiles in an adolescent sample. Participants (N = 304) were categorized into four affective profiles: "self-fulfilling" (high PA, low NA), "high affective" (high PA, high NA), "low affective" (low PA, low NA), and "self-destructive" (low PA, high NA). Personality was measured by the Temperament and Character Inventory and affective profiles by the Positive Affect and Negative Affect Schedule. The "self-fulfilling" profile was characterized by, compared to the other affective profiles, higher levels of sleep quality, less stress and more energy and also higher levels of persistence and a mature character (i.e., high scores in self-directedness and cooperativeness). "Self-destructive" adolescents reported higher levels of external locus of control, high scores in harm avoidance and reward dependence combined with less mature character. The results identify the importance of character maturity in well-being and suggest that depressive state can be positively influenced by promoting positive emotions which appears to be achieved by character development. © 2012 Danilo Garcia et al.

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