Coupled analysis of transport processes and mechanical behaviour of concrete at high temperatures

A model for the numerical analysis of hygro-thermal and mechanical behaviour of concrete at high temperatures including transport, reaction and deformation processes is presented. For the description of transport and material behaviour the model comprises the balance equations for mass and enthalpy and the constitutive equations for concrete at high temperatures. The degradation of the cement minerals C-S-H and portlandite is described by two chemical reactions. The consideration of thermo-chemical damage in the classical non-local damage theory is discussed. Finally, the finite element formulation for solving the coupled balance equations regarding the primary variables displacement, temperature and relative humidity is presented and numerical results of a 3-D frame corner are discussed

No neurochemical evidence of neuronal injury or glial activation in children with Pediatric Acute-onset Neuropsychiatric Syndrome: An explorative pilot study

OBJECTIVE: Paediatric Acute-onset Neuropsychiatric Syndrome (PANS) is characterised by an acute onset of obsessive compulsive disorder, combined with at least two other neuropsychiatric symptoms with acute onset. Diagnostic criteria also require that no specific medical aetiology is identified. Although there are no verified aetiological biomarkers, PANS is assumed to be a neuroinflammatory disorder with a possible autoimmune aetiology. Neurochemical markers such as neurofilament light (NfL, a neuronal injury marker) and glial fibrillary acidic protein (GFAP, an astrocytic activation marker) have not been published for this patient group. METHOD: Blood samples from 17 children meeting diagnostic criteria for PANS, after assessment at a child neuropsychiatry clinic were analysed for serum concentrations of NfL and GFAP. Ten age-matched children without any neurological or psychiatric disorder served as a comparison group. RESULTS: No difference was found in mean NfL and mean GFAP serum concentrations between children with PANS and controls. CONCLUSION: Neuronal injury and astrocyte activation do not seem to be a major event in PANS. The study group was small, and even if findings may be reassuring for parents and patients, they should be interpreted with caution and verified in larger cohorts and possibly with other markers in both serum and CSF

Anorexia nervosa and autism: a prospective twin cohort study

Background: Anorexia nervosa (AN) and autism spectrum disorder (ASD) may be phenotypically and etiologically linked. However, due to the absence of prospective studies, it remains unclear whether the elevation of autistic traits in AN is evident in early childhood. Here, we prospectively investigated autistic traits before and after the first diagnosis of AN. Methods: In a population-based sample of 5,987 individuals (52.4% female) from the Child and Adolescent Twin Study in Sweden, parents reported autistic traits at ages 9 and 18. AN and ASD diagnoses were retrieved from the Swedish National Patient Register. In addition, AN diagnoses were ascertained by parent-reported treatment for AN. We compared whether individuals with and without AN differed in autistic traits before the first diagnosis of AN (age 9) and after the first diagnosis of AN (age 18). Results: We did not find evidence for elevated autistic traits in 9-year-old children later diagnosed with AN. At age 18, however, there was a marked elevation in restricted/repetitive behavior and interests, but only in the subgroup of individuals with acute AN. A less pronounced elevation was observed for social communication problems. Conclusions: Coping strategies in individuals with ASD and the somewhat different female ASD phenotype may explain why we did not find elevated autistic traits in children who later developed AN. Alternatively, it is possible that elevated autistic traits were not present prior to the onset of AN, thus questioning the previously reported elevated prevalence of ASD in AN. Future studies should use tailored measurements in order to investigate whether autistic traits in individuals with AN are best conceptualized as an epiphenomenon of the acute AN phase or whether these symptoms indeed represent ASD as a clinically verifiable neurodevelopmental disorder

Association of etiological factors across the extreme end and continuous variation in disordered eating in female Swedish twins

Background: Accumulating evidence suggests that many psychiatric disorders etiologically represent the extreme end of dimensionally distributed features rather than distinct entities. The extent to which this applies to eating disorders (EDs) is unknown. Methods: We investigated if there is similar etiology in (a) the continuous distribution of the Eating Disorder Inventory-2 (EDI-2), (b) the extremes of EDI-2 score, and (c) registered ED diagnoses, in 1481 female twin pairs at age 18 years (born 1992-1999). EDI-2 scores were self-reported at age 18. ED diagnoses were identified through the Swedish National Patient Register, parent-reported treatment and/or self-reported purging behavior of a frequency and duration consistent with DSM-IV criteria. We differentiated between anorexia nervosa (AN) and other EDs. Results: The heritability of the EDI-2 score was 0.65 (95% CI 0.61-0.68). The group heritabilities in DeFries-Fulker extremes analyses were consistent over different percentile-based extreme groups [0.59 (95% CI 0.37-0.81) to 0.65 (95% CI 0.55-0.75)]. Similarly, the heritabilities in liability threshold models were consistent over different levels of severity. In joint categorical-continuous models, the twin-based genetic correlation was 0.52 (95% CI 0.39-0.65) between EDI-2 score and diagnoses of other EDs, and 0.26 (95% CI 0.08-0.42) between EDI-2 score and diagnoses of AN. The non-shared environmental correlations were 0.52 (95% CI 0.32-0.70) and 0.60 (95% CI 0.38-0.79), respectively. Conclusions: Our findings suggest that some EDs can partly be conceptualized as the extreme manifestation of continuously distributed ED features. AN, however, might be more distinctly genetically demarcated from ED features in the general population than other EDs

Gray matter imaging in multiple sclerosis: what have we learned?

At the early onset of the 20th century, several studies already reported that the gray matter was implicated in the histopathology of multiple sclerosis (MS). However, as white matter pathology long received predominant attention in this disease, and histological staining techniques for detecting myelin in the gray matter were suboptimal, it was not until the beginning of the 21st century that the true extent and importance of gray matter pathology in MS was finally recognized. Gray matter damage was shown to be frequent and extensive, and more pronounced in the progressive disease phases. Several studies subsequently demonstrated that the histopathology of gray matter lesions differs from that of white matter lesions. Unfortunately, imaging of pathology in gray matter structures proved to be difficult, especially when using conventional magnetic resonance imaging (MRI) techniques. However, with the recent introduction of several more advanced MRI techniques, the detection of cortical and subcortical damage in MS has considerably improved. This has important consequences for studying the clinical correlates of gray matter damage. In this review, we provide an overview of what has been learned about imaging of gray matter damage in MS, and offer a brief perspective with regards to future developments in this field

The variability of the marine atmospheric boundary layer in the Greenland Sea marginal ice zone a case study.

The vertical structure of the atmospheric boundary layer in the East Greenland Sea Fram Strait marginal ice zone (MIZ) is examined for various wind flow regimes with respect to the ice edge. Rawinsonde profiles and surface observations collected from three ships during MIZEX-87 (20 March - 11 April 1987) served as the data set for the examination. Three specific flow regimes are discussed: on-ice flow, off-ice flow, and flow parallel to the ice. On-ice flow resulted in deep, moist layers capped by high weak inversions at the MIZ. Off-ice flow resulted in multiple surface and elevated inversions, with specific humidity highest within an elevated lower-tropospheric layer and dry regions near the surface and aloft. Parallel flow led to the development of strikingly different boundary layer regimes separated by the ice edge: Over ice, deep surface and elevated inversions were associated with alternating moist and dry layers in the lower troposphere; over water, multiple elevated inversions were associated with an elevated lower-tropospheric moist layer and dry regions near the surface and aloft. Possible physical processes important for the development of the observed features are discussed.http://archive.org/details/variabilityofmar00dinkLieutenant, United States NavyApproved for public release; distribution is unlimited

Thirty years after anorexia nervosa onset, serum neurofilament light chain protein concentration indicates neuronal injury

Little is known about the long-term consequences of anorexia nervosa (AN) in terms of possible brain neuronal injury. We aimed at investigating whether women with adolescent-onset AN exhibit increased serum levels of neurofilament light chain protein (NfL), a biomarker for neuronal injury, compared with matched controls at 30-year follow-up. Blood samples were collected from 34 women with adolescent-onset AN and 38 matched healthy comparison women (COMP), at a mean age of 44 years (range 38-48 years). NfL was measured in serum using the in-house single molecule array (Simoa) method. The individuals were asked whether they or their parents had been diagnosed with dementia. The Swedish National Patient Register was searched for diagnoses related to dementia. Serum NfL concentrations were significantly higher in the AN group (AN 27.7 pg/ml; COMP 19.0 pg/ml; p = 0.041). When individuals with medical/neurological disorders in the AN and COMP groups were excluded, there was a statistically non-significant trend towards higher concentrations in the AN group (AN 27.4 pg/ml; COMP 18.8 pg/ml; p = 0.060). None of the participants had been diagnosed with dementia. There was no significant correlation between serum NfL and AN duration (r = 0.15). There was a moderate negative correlation between the serum NfL concentration and the current BMI in the AN group (r = 0.44). This is the first time that serum NfL has been assessed in middle-aged women with a history of adolescent-onset AN. The results suggest that there might be increased axonal degeneration as a sequel of AN. Individuals remaining underweight had higher serum NfL concentrations than those with a normal/high BMI. Additional studies are needed to confirm increased serum NfL concentrations in individuals recovered from AN. There is a need for further study of axonal degeneration as a consequence of AN