| 1. |
- Niemi, MEK, et al.
(författare)
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- 2021
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swepub:Mat__t
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| 2. |
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| 3. |
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| 4. |
- Buchanan, E. M., et al.
(författare)
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The Psychological Science Accelerator's COVID-19 rapid-response dataset
- 2023
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Ingår i: Scientific Data. - : Springer Science and Business Media LLC. - 2052-4463. ; 10:1
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Tidskriftsartikel (refereegranskat)abstract
- In response to the COVID-19 pandemic, the Psychological Science Accelerator coordinated three large-scale psychological studies to examine the effects of loss-gain framing, cognitive reappraisals, and autonomy framing manipulations on behavioral intentions and affective measures. The data collected (April to October 2020) included specific measures for each experimental study, a general questionnaire examining health prevention behaviors and COVID-19 experience, geographical and cultural context characterization, and demographic information for each participant. Each participant started the study with the same general questions and then was randomized to complete either one longer experiment or two shorter experiments. Data were provided by 73,223 participants with varying completion rates. Participants completed the survey from 111 geopolitical regions in 44 unique languages/dialects. The anonymized dataset described here is provided in both raw and processed formats to facilitate re-use and further analyses. The dataset offers secondary analytic opportunities to explore coping, framing, and self-determination across a diverse, global sample obtained at the onset of the COVID-19 pandemic, which can be merged with other time-sampled or geographic data.
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| 9. |
- Kerkhof, H. J. M., et al.
(författare)
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Recommendations for standardization and phenotype definitions in genetic studies of osteoarthritis: the TREAT-OA consortium
- 2011
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Ingår i: Osteoarthritis and Cartilage. - : Elsevier BV. - 1063-4584. ; 19:3, s. 254-264
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Tidskriftsartikel (refereegranskat)abstract
- Objective: To address the need for standardization of osteoarthritis (OA) phenotypes by examining the effect of heterogeneity among symptomatic (SOA) and radiographic osteoarthritis (ROA) phenotypes. Methods: Descriptions of OA phenotypes of the 28 studies involved in the TREAT-OA consortium were collected. We investigated whether different OA definitions result in different association results by creating various hip OA definitions in one large population based cohort (the Rotterdam Study I (RSI)) and testing those for association with gender, age and body mass index using one-way ANOVA. For ROA, we standardized the hip-, knee- and hand ROA definitions and calculated prevalence's of ROA before and after standardization in nine cohort studies. This procedure could only be performed in cohort studies and standardization of SOA definitions was not feasible at this moment. Results: In this consortium, all studies with SOA phenotypes (knee, hip and hand) used a different definition and/or assessment of OA status. For knee-, hip- and hand ROA five, four and seven different definitions were used, respectively. Different hip ROA definitions do lead to different association results. For example, we showed in the RSI that hip OA defined as "at least definite joint space narrowing (JSN) and one definite osteophyte" was not associated with gender (P=0.22), but defined as "at least one definite osteophyte" was significantly associated with gender (P=3 x 10(-9)). Therefore, a standardization process was undertaken for ROA definitions. Before standardization a wide range of ROA prevalence's was observed in the nine cohorts studied. After standardization the range in prevalence of knee- and hip ROA was small. Conclusion: Phenotype definitions influence the prevalence of OA and association with clinical variables. ROA phenotypes within the TREAT-OA consortium were standardized to reduce heterogeneity and improve power in future genetics studies. (C) 2010 Osteoarthritis Research Society International. Published by Elsevier Ltd. All rights reserved.
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| 10. |
- Patel, Y., et al.
(författare)
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Virtual Ontogeny of Cortical Growth Preceding Mental Illness
- 2022
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Ingår i: Biological Psychiatry. - : Elsevier BV. - 0006-3223 .- 1873-2402. ; 92:4, s. 299-313
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Tidskriftsartikel (refereegranskat)abstract
- Background: Morphology of the human cerebral cortex differs across psychiatric disorders, with neurobiology and developmental origins mostly undetermined. Deviations in the tangential growth of the cerebral cortex during pre/perinatal periods may be reflected in individual variations in cortical surface area later in life. Methods: Interregional profiles of group differences in surface area between cases and controls were generated using T1-weighted magnetic resonance imaging from 27,359 individuals including those with attention-deficit/hyperactivity disorder, autism spectrum disorder, bipolar disorder, major depressive disorder, schizophrenia, and high general psychopathology (through the Child Behavior Checklist). Similarity of interregional profiles of group differences in surface area and prenatal cell-specific gene expression was assessed. Results: Across the 11 cortical regions, group differences in cortical area for attention-deficit/hyperactivity disorder, schizophrenia, and Child Behavior Checklist were dominant in multimodal association cortices. The same interregional profiles were also associated with interregional profiles of (prenatal) gene expression specific to proliferative cells, namely radial glia and intermediate progenitor cells (greater expression, larger difference), as well as differentiated cells, namely excitatory neurons and endothelial and mural cells (greater expression, smaller difference). Finally, these cell types were implicated in known pre/perinatal risk factors for psychosis. Genes coexpressed with radial glia were enriched with genes implicated in congenital abnormalities, birth weight, hypoxia, and starvation. Genes coexpressed with endothelial and mural genes were enriched with genes associated with maternal hypertension and preterm birth. Conclusions: Our findings support a neurodevelopmental model of vulnerability to mental illness whereby prenatal risk factors acting through cell-specific processes lead to deviations from typical brain development during pregnancy.
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| 11. |
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| 15. |
- Lynch, I, et al.
(författare)
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Can an InChI for Nano Address the Need for a Simplified Representation of Complex Nanomaterials across Experimental and Nanoinformatics Studies?
- 2020
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Ingår i: Nanomaterials (Basel, Switzerland). - : MDPI AG. - 2079-4991. ; 10:12
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Tidskriftsartikel (refereegranskat)abstract
- Chemoinformatics has developed efficient ways of representing chemical structures for small molecules as simple text strings, simplified molecular-input line-entry system (SMILES) and the IUPAC International Chemical Identifier (InChI), which are machine-readable. In particular, InChIs have been extended to encode formalized representations of mixtures and reactions, and work is ongoing to represent polymers and other macromolecules in this way. The next frontier is encoding the multi-component structures of nanomaterials (NMs) in a machine-readable format to enable linking of datasets for nanoinformatics and regulatory applications. A workshop organized by the H2020 research infrastructure NanoCommons and the nanoinformatics project NanoSolveIT analyzed issues involved in developing an InChI for NMs (NInChI). The layers needed to capture NM structures include but are not limited to: core composition (possibly multi-layered); surface topography; surface coatings or functionalization; doping with other chemicals; and representation of impurities. NM distributions (size, shape, composition, surface properties, etc.), types of chemical linkages connecting surface functionalization and coating molecules to the core, and various crystallographic forms exhibited by NMs also need to be considered. Six case studies were conducted to elucidate requirements for unambiguous description of NMs. The suggested NInChI layers are intended to stimulate further analysis that will lead to the first version of a “nano” extension to the InChI standard.
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| 16. |
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| 17. |
- Béland, Laurent Karim, et al.
(författare)
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Accurate classical short-range forces for the study of collision cascades in Fe-Ni-Cr
- 2017
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Ingår i: Computer Physics Communications. - : Elsevier BV. - 0010-4655 .- 1879-2944. ; 219, s. 11-19
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Tidskriftsartikel (refereegranskat)abstract
- The predictive power of a classical molecular dynamics simulation is largely determined by the physical validity of its underlying empirical potential. In the case of high-energy collision cascades, it was recently shown that correctly modeling interactions at short distances is necessary to accurately predict primary damage production. An ab initio based framework is introduced for modifying an existing embedded atom method FeNiCr potential to handle these short-range interactions. Density functional theory is used to calculate the energetics of two atoms approaching each other, embedded in the alloy, and to calculate the equation of state of the alloy as it is compressed. The pairwise terms and the embedding terms of the potential are modified in accordance with the ab initio results. Using this reparametrized potential, collision cascades are performed in Ni50Fe50, Ni80Cr20 and Ni33Fe33Cr33. The simulations reveal that alloying Ni and NiCr to Fe reduces primary damage production, in agreement with some previous calculations. Alloying Ni and NiFe to Cr does not reduce primary damage production, in contradiction with previous calculations.
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| 18. |
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| 19. |
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| 20. |
- Frech, Wolfgang, et al.
(författare)
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Characterization of a pressurizable two-step atomizer for atomic absorption spectrometry
- 2000
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Ingår i: Spectrochimica Acta Part B: Atomic Spectroscopy. ; 55:5, s. 461-72
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Tidskriftsartikel (refereegranskat)abstract
- A two-step atomizer consisting of a transversely heated atomization tube with integrated contacts and a cup furnace for sample vaporization was constructed. The system could accommodate tubes of various lengths and it could be operated at selected pressures. There was no physical contact between the tube and the cup and mainly diffusion was responsible for the sample vapour transport from the cup to the tube. Under these conditions there was an unavoidable loss by 40% of the peak area signals due to the gap between the cup and the tube. For a 24-mm tube, characteristic masses were on the average three times lower than for the state of the art transverse heated graphite atomizers (THGA). By de-coupling the processes of analyte vaporization and atomization the dynamic working range could be increased by three to six times using conventional measurements by atomic absorption spectrometry (AAS). In this case the cup temperature and hence the rate of analyte transport from the cup to the tube was controlled such that atom density in the tube did not exceed the linear range of the absorbance measurement. Carrying out clean-out steps at reduced pressure decreased memory effects.
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| 21. |
- Koenig, Julian, et al.
(författare)
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Cortical thickness and resting-state cardiac function across the lifespan : A cross-sectional pooled mega-analysis
- 2021
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Ingår i: Psychophysiology. - : Wiley. - 0048-5772 .- 1469-8986 .- 1540-5958. ; 58:7
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Tidskriftsartikel (refereegranskat)abstract
- Understanding the association between autonomic nervous system [ANS] function and brain morphology across the lifespan provides important insights into neurovisceral mechanisms underlying health and disease. Resting-state ANS activity, indexed by measures of heart rate [HR] and its variability [HRV] has been associated with brain morphology, particularly cortical thickness [CT]. While findings have been mixed regarding the anatomical distribution and direction of the associations, these inconsistencies may be due to sex and age differences in HR/HRV and CT. Previous studies have been limited by small sample sizes, which impede the assessment of sex differences and aging effects on the association between ANS function and CT. To overcome these limitations, 20 groups worldwide contributed data collected under similar protocols of CT assessment and HR/HRV recording to be pooled in a mega-analysis (N = 1,218 (50.5% female), mean age 36.7 years (range: 12–87)). Findings suggest a decline in HRV as well as CT with increasing age. CT, particularly in the orbitofrontal cortex, explained additional variance in HRV, beyond the effects of aging. This pattern of results may suggest that the decline in HRV with increasing age is related to a decline in orbitofrontal CT. These effects were independent of sex and specific to HRV; with no significant association between CT and HR. Greater CT across the adult lifespan may be vital for the maintenance of healthy cardiac regulation via the ANS—or greater cardiac vagal activity as indirectly reflected in HRV may slow brain atrophy. Findings reveal an important association between CT and cardiac parasympathetic activity with implications for healthy aging and longevity that should be studied further in longitudinal research.
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| 22. |
- Kukli, K., et al.
(författare)
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Atomic layer deposition of ZrO2 and HfO2 on deep trenched and planar silicon
- 2007
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Ingår i: Microelectronic Engineering. - : Elsevier BV. - 0167-9317 .- 1873-5568. ; 84:9-10, s. 2010-2013
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Tidskriftsartikel (refereegranskat)abstract
- Conformal ZrO2 and HfO2 thin films were grown by atomic layer deposition using novel liquid cyclopentadienyl precursors at 300 degrees C or 350 degrees C on planar Si wafers and deep trenched Si with an aspect ratio of 60:1. The crystal growth and phase content in as-deposited films depended on the precursor, film thickness, and the material grown. The structural and electrical behaviour of the films were somewhat precursor-dependent, revealing better insulating properties in the films grown from oxygen-containing precursors. Also the HfO2 films showed lower leakage compared to ZrO2.
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| 23. |
- Niinisto, Jaakko, et al.
(författare)
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Advanced cyclopentadienyl precursors for atomic layer deposition of ZrO2 thin films
- 2008
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Ingår i: Journal of Materials Chemistry. - : Royal Society of Chemistry (RSC). - 0959-9428 .- 1364-5501. ; 18:28, s. 3385-3390
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Tidskriftsartikel (refereegranskat)abstract
- ZrO2 thin films were grown onto silicon (100) substrates by atomic layer deposition (ALD) using novel cyclopentadienyl-type precursors, namely (CpMe)(2)ZrMe2 and (CpMe)(2)Zr(OMe) Me (Cp = cyclopentadienyl, C5H5) together with ozone as the oxygen source. Growth characteristics were studied in the temperature range of 250 to 500 degrees C. An ALD-type self-limiting growth mode was verified for both processes at 350 degrees C where highly conformal films were deposited onto high aspect ratio trenches. Signs of thermal decomposition were not observed at or below 400 degrees C, a temperature considerably exceeding the thermal decomposition temperature of the Zr-alkylamides. Processing parameters were optimised at 350 degrees C, where deposition rates of 0.55 and 0.65 angstrom cycle(-1) were obtained for (CpMe)(2)ZrMe2/O-3 and (CpMe)(2)Zr(OMe)Me/O-3, respectively. The films grown from both precursors were stoichiometric and polycrystalline with an increasing contribution from the metastable cubic phase with decreasing film thickness. In the films grown from (CpMe)(2)ZrMe2, the breakdown field did not essentially depend on the film thickness, whereas in the films grown from (CpMe)(2)Zr(OMe)Me the structural homogeneity and breakdown field increased with decreasing film thickness. The films exhibited good capacitive properties that were characteristic of insulating oxides and did not essentially depend on the precursor chemistry.
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| 24. |
- Nilsonne, Gustav, et al.
(författare)
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A multimodal brain imaging dataset on sleep deprivation in young and old humans
- 2017
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- The Stockholm Sleepy Brain Study I is a functional brain imaging study of 48 younger (20-30 years) and 36 older (65-75 years) healthy participants, with magnetic resonance imaging after normal sleep and partial sleep deprivation in a crossover design. We performed experiments investigating emotional mimicry, empathy for pain, and cognitive reappraisal, as well as resting state functional magnetic resonance imaging (fMRI). We also acquired T1- and T2-weighted structural images and diffusion tensor images (DTI). On the night before imaging, participants were monitored with ambulatory polysomnography and were instructed to sleep either as usual or only three hours. Participants came to the scanner the following evening. Besides MRI scanning, participants underwent behavioral tests and contributed blood samples, which have been stored in a biobank and used for DNA analyses. Participants also completed a variety of self-report measures. The resulting multimodal dataset may be useful for hypothesis generation or independent validation of effects of sleep deprivation and aging, as well as investigation of cross-sectional associations between the different outcomes. V. 2 of this manuscript published 2017-10-12. Changes: new co-author (Claus Lamm), changed affiliations for Kristoffer Månsson, minor changes in the abstract, and revisions of the main text and figures.
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| 25. |
- Nilsonne, Gustav, et al.
(författare)
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Leukocyte telomere length and hippocampus volume : a meta-analysis [version 1; referees: 2 approved]
- 2015
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Ingår i: F1000 Research. - : F1000 Research Ltd. - 2046-1402. ; 4
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Forskningsöversikt (refereegranskat)abstract
- Leukocyte telomere length has been shown to correlate to hippocampus volume, but effect estimates differ in magnitude and are not uniformly positive. This study aimed primarily to investigate the relationship between leukocyte telomere length and hippocampus gray matter volume by meta-analysis and secondarily to investigate possible effect moderators. Five studies were included with a total of 2107 participants, of which 1960 were contributed by one single influential study. A random-effects meta-analysis estimated the effect to r = 0.12 [95% CI -0.13, 0.37] in the presence of heterogeneity and a subjectively estimated moderate to high risk of bias. There was no evidence that apolipoprotein E (APOE) genotype was an effect moderator, nor that the ratio of leukocyte telomerase activity to telomere length was a better predictor than leukocyte telomere length for hippocampus volume. This meta-analysis, while not proving a positive relationship, also is not able to disprove the earlier finding of a positive correlation in the one large study included in analyses. We propose that a relationship between leukocyte telomere length and hippocamus volume may be mediated by transmigrating monocytes which differentiate into microglia in the brain parenchyma.
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| 26. |
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| 28. |
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| 29. |
- Serviss, J. T., et al.
(författare)
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An antisense RNA capable of modulating the expression of the tumor suppressor microRNA-34a
- 2018
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Ingår i: Cell Death & Disease. - : Springer Science and Business Media LLC. - 2041-4889. ; 9:7
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Tidskriftsartikel (refereegranskat)abstract
- The microRNA-34a is a well-studied tumor suppressor microRNA (miRNA) and a direct downstream target of TP53 with roles in several pathways associated with oncogenesis, such as proliferation, cellular growth, and differentiation. Due to its broad tumor suppressive activity, it is not surprising that miR34a expression is altered in a wide variety of solid tumors and hematological malignancies. However, the mechanisms by which miR34a is regulated in these cancers is largely unknown. In this study, we find that a long noncoding RNA transcribed antisense to the miR34a host gene, is critical for miR34a expression and mediation of its cellular functions in multiple types of human cancer. We name this long noncoding RNA lncTAM34a, and characterize its ability to facilitate miR34a expression under different types of cellular stress in both TP53-deficient and wild-type settings.
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| 30. |
- Stoller, R. E., et al.
(författare)
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Impact of Short-Range Forces on Defect Production from High Energy Collisions
- 2016
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Ingår i: Journal of Chemical Theory and Computation. - : American Chemical Society (ACS). - 1549-9618 .- 1549-9626. ; 12:6, s. 2871-2879
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Tidskriftsartikel (refereegranskat)abstract
- Primary radiation damage formation in solid materials typically involves collisions between atoms that have up to a few hundred keV of kinetic energy. Dining these collisions, the-distance between two colliding atoms can approach 0.05 nm. At such small atomic separations, force fields fitted-to equilibrium properties tend to significantly underestimate the potential-energy-of the colliding dieter. To enable molecular dynamics simulations of high-energy collisions, it is common practice to use a screened Coulomb, force field to describe the interactions and to smoothly join this to the equilibrium force field at a suitable interatomic spacing. However, there is,no accepted standard method for choosing the parameters used in the joining process, and our results prove that defect production is sensitive to how the force field's are linked. A new procedure is presented that involves the use of ab initio calculations to,determine the magnitude and spatial dependence of the pair interactions at intermediate distances, along with systematic criteria for choosing the joining parameters. Results are presented for the case of nickel, which demonstrate the use and validity of the procedure.
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| 31. |
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| 32. |
- Strobel, Werner, et al.
(författare)
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Topical nasal steroid treatment does not improve CPAP compliance in unselected patients with OSAS
- 2011
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Ingår i: Respiratory Medicine. - : Elsevier BV. - 1532-3064 .- 0954-6111. ; 105:2, s. 310-315
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Tidskriftsartikel (refereegranskat)abstract
- Background: Continuous positive airways pressure (CPAP) for treatment of obstructive sleep apnea (OSA) can produce troublesome nasal symptoms (i.e. congestion, rhinorrhea) that may reduce the compliance of CPAP. Topical nasal steroids are often prescribed to reduce these side effects, although scientific data are scarce supporting any benefits of this treatment for CPAP-induced nasal side effects. Objective: To study whether a topical nasal steroid can reduce CPAP-induced nasal symptoms and improve CPAP adherence during the initial phase of OSA treatment. Methods: A randomized, double-blinded, placebo-controlled study with fluticasone propionate 100 mu g/nasal cavity twice daily Treatment was started 10 days prior to and continued throughout the first 4 weeks of CPAP. 63 patients who were selected for CPAP treatment participated. Nasal symptoms were recorded, nasal patency was assessed and lung function was measured with a peak flow meter. The patients' adherence to CPAP was recorded by the CPAP device. Results: Total nasal symptoms increased from baseline to 4 wks after CPAP use for both nasal treatments (p < 0.05). No differences in total nasal symptoms between treatments were seen (p = 1), and no differences in nasal peak flow values after treatment were seen (p = 0.11). Moreover, there were no differences in CPAP use between the treatments. Conclusion: Fluticasone propionate as a nasal topical steroid does not reduce CPAP-induced unwanted nasal side effects, and has no beneficial effect on CPAP compliance during the first four weeks of treatment in unselected patients with OSAS. (C) 2010 Elsevier Ltd. All rights reserved.
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| 33. |
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| 34. |
- Walander, Magnus, 1991, et al.
(författare)
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Modelling of Mass Transfer Resistances in Non-uniformly Washcoated Monolith Reactors
- 2021
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Ingår i: Emission Control Science and Technology. - : Springer Science and Business Media LLC. - 2199-3629 .- 2199-3637. ; 7:2, s. 153-162
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Tidskriftsartikel (refereegranskat)abstract
- There are various methodologies to account for mass transfer within non-uniformly distributed washcoats in monolith reactors in 1D models (axially). However, 1+1D models (axially/radially) fail to capture local variations in mass transfer from different coating thicknesses or cracks. In this paper, we present a novel way to account for local material properties in a washcoated monolith reactor. The suggested method uses an existing 1+1D modelling framework and sectionalizes the washcoat into multiple tangential segments which are solved independently. Intelligent gravimetric analysis and scanning electron microscopy are used in combination to calculate local effective diffusivity as an input for each simulation. The new model is compared to the original 1+1D model using NO light-off simulations. The new model predicted increased conversion at elevated temperatures, where mass transfer limitations are present, due to the higher porosity in the corners. The simulation time for each model was similar due to the parallelizable nature of the new model.
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| 35. |
- Zamora, Juan Carlos, et al.
(författare)
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Considerations and consequences of allowing DNA sequence data as types of fungal taxa
- 2018
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Ingår i: IMA Fungus. - : INT MYCOLOGICAL ASSOC. - 2210-6340 .- 2210-6359. ; 9:1, s. 167-185
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Tidskriftsartikel (refereegranskat)abstract
- Nomenclatural type definitions are one of the most important concepts in biological nomenclature. Being physical objects that can be re-studied by other researchers, types permanently link taxonomy (an artificial agreement to classify biological diversity) with nomenclature (an artificial agreement to name biological diversity). Two proposals to amend the International Code of Nomenclature for algae, fungi, and plants (ICN), allowing DNA sequences alone (of any region and extent) to serve as types of taxon names for voucherless fungi (mainly putative taxa from environmental DNA sequences), have been submitted to be voted on at the 11th International Mycological Congress (Puerto Rico, July 2018). We consider various genetic processes affecting the distribution of alleles among taxa and find that alleles may not consistently and uniquely represent the species within which they are contained. Should the proposals be accepted, the meaning of nomenclatural types would change in a fundamental way from physical objects as sources of data to the data themselves. Such changes are conducive to irreproducible science, the potential typification on artefactual data, and massive creation of names with low information content, ultimately causing nomenclatural instability and unnecessary work for future researchers that would stall future explorations of fungal diversity. We conclude that the acceptance of DNA sequences alone as types of names of taxa, under the terms used in the current proposals, is unnecessary and would not solve the problem of naming putative taxa known only from DNA sequences in a scientifically defensible way. As an alternative, we highlight the use of formulas for naming putative taxa (candidate taxa) that do not require any modification of the ICN.
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| 36. |
- Åkerstedt, Torbjörn, et al.
(författare)
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Gray Matter Volume Correlates Of Sleepiness : A Voxel-based Morphometry Study In Younger And Older Adults
- 2018
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Ingår i: Sleep. - : Oxford University Press (OUP). - 0161-8105 .- 1550-9109. ; 27
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- Introduction: Sleepiness is prevalent in society, often linked to disturbed sleep, shift work, stress, or diseases. It is also associated with an increased risk of accidents. Sleepiness may be related to brain metabolism and, we hypothesize that it is associated with brain gray matter (GM) volume. The present study investigated the association between sleepiness and GM volume in thalamus and insula, with a special focus on age, since both sleepiness and GM volume change with age.Methods: In all, 84 healthy individuals participated in the experiment, of which 46 were in the age range 20–30 years and 38 ranging between 65–75 years. Data was collected in a 3 T scanner during a 5 minute anatomical scan (first in a several sessions in the scanner) in the evening after a full night of sleep. Momentary sleepiness (Karolinska Sleepiness Scale) was rated 7 times during the time in the scanner.Results: Results showed that, in older, relative to younger adults, areas within bilateral insular cortex and thalamus GM regions of interest were negatively associated (FWE-corrected) with sleepiness (Z=4.02, p=.015 left insula and Z=4.42, p=.009 for right insula; Z=3.75, p=.020 for left thalamus and Z=4.60, p=.001 for right thalamus). Larger volume was associated with low sleepiness in the older group, but not in the older group. The effect in the insula was mainly present in the mid-anterior parts of the structure.. In addition, after applying a conservative small volume correction including all ROIs simultaneously, age-interaction effects remained significant.Conclusion: It was concluded that self-rated momentary sleepiness in a monotonous situation is negatively associated with GM volume in areas within both thalamus and insula in older individuals. The results are in line with notions of thalamus as a driver of arousal and of anterior insula as a structure evaluating the state of the organism. Possibly, a larger GM volume in these structures may be protective against sleepiness in older individuals, a hypothesis that needs confirmation in further studies.
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