1,219 research outputs found
Construct and correlates of basic motor competencies in primary school-aged children
Background: A central aim of physical education is the promotion of basic motor competencies (in German: Motorische Basiskompetenzen; MOBAK), which are prerequisites for children’s active participation in sports culture. This article introduces the MOBAK-1 test instrument for 6- to 8-year-old children and determines the construct validity of this test instrument. In addition, the relationship between MOBAK and motor ability (i.e., strength) as well as body mass index (BMI), sex, and age is investigated. Methods: We analyzed data of 923 first and second graders (422 girls, 501 boys, age = 6.80 +/- 0.44 years). The children’s basic motor competencies were assessed by the MOBAK-1 test instrument. Besides analyses of frequency, correlation, and variance, 3 confirmatory factor analyses with covariates were performed.
Results: We found 2 MOBAK factors consisting of 4 items each. The first factor, locomotion, included the items balancing, rolling, jumping, and side stepping; the second factor, object control, included the items throwing, catching, bouncing, and dribbling. The motor ability strength had a significant influence on the factors locomotion (β = 0.60) and object control (β = 0.50). Older pupils achieved better results than younger pupils on object control (β = 0.29). Boys performed better on object control (β = -0.44), whereas girls achieved better results in locomotion (β = 0.07). Pupils with a high BMI achieved lower performance only on the factor locomotion (β = -0.28).
Conclusion: The MOBAK-1 test instrument developed for this study meets psychometric validity demands and is suitable to evaluate effects of sports and physical education.+repphzhbib2019
Prehypertensive blood pressures and regional cerebral blood flow independently relate to cognitive performance in midlife
Background
High blood pressure is thought to contribute to dementia in late life, but our understanding of the relationship between individual differences in blood pressure (
BP
) and cognitive functioning is incomplete. In this study, cognitive performance in nonhypertensive midlife adults was examined as a function of resting
BP
and regional cerebral blood flow (
rCBF
) responses during cognitive testing. We hypothesized that
BP
would be negatively related to cognitive performance and that cognitive performance would also be related to
rCBF
responses within areas related to
BP
control. We explored whether deficits related to systolic
BP
might be explained by
rCBF
responses to mental challenge.
Methods and Results
Healthy midlife participants (n=227) received neuropsychological testing and performed cognitive tasks in a magnetic resonance imaging scanner. A pseudocontinuous arterial spin labeling sequence assessed
rCBF
in brain areas related to
BP
in prior studies. Systolic
BP
was negatively related to 4 of 5 neuropsychological factors (standardized β>0.13): memory, working memory, executive function, and mental efficiency. The
rCBF
in 2 brain regions of interest was similarly related to memory, executive function, and working memory (standardized β>0.17); however,
rCBF
responses did not explain the relationship between resting systolic
BP
and cognitive performance.
Conclusions
Relationships at midlife between prehypertensive levels of systolic
BP
and both cognitive and brain function were modest but suggested the possible value of midlife intervention.
</jats:sec
Molecular pathways elicited by Toll-like receptor 2 (TLR2) signaling during Staphylococcus aureus craniotomy infection
A craniotomy is required to access the brain during neurosurgery for tumor resection or epilepsy treatment and despite extensive precautionary measures, infectious complications occur at a frequency of 1-3% (1-3). Approximately half of craniotomy infections are caused by S. aureus, which forms a biofilm on the bone flap. Our laboratory has developed a mouse model of S. aureus craniotomy-associated biofilm infection that shares important ultrastructural and MRI attributes with human disease (4). Toll-like receptor 2 (TLR2) is expressed by cells of the innate immune system and is critical for recognizing pathogen-associated molecular patterns (PAMPs) in the cell wall of gram-positive bacteria, such as S. aureus. Recent studies have shown that TLR2 is critical for S. aureus containment during craniotomy infection, in that TLR2 knockout (KO) mice displayed increased bacterial burden in the brain, galea, and bone flap during acute and chronic infection (days 3 and 14, respectively)(5). Cytokine and chemokine expression was dramatically reduced in TLR2 KO mice which did not coincide with a decrease in leukocyte infiltrates in the brain or galea. This suggested that S. aureus outgrowth in the context of TLR2 deficiency is not the result of altered leukocyte recruitment, but instead due to defects in their activation status. To determine this, RNA-sequencing (RNA-seq) was performed on microglia purified from the brain of WT and TLR2 KO mice at either day 3 or 7 post-infection by FACS with the goal of identifying microglial transcripts that are divergent between the two mouse strains (either increased or decreased). RNA-seq revealed Fibroblast Growth Factor Receptor (FGFR) 2 and 3 were upregulated in TLR2 KO microglia. This suggests a direct correlation between TLR2, FGFR2 and FGFR3. Since TLR2 KO animals have a bias toward an anti-inflammatory response to infection and the fact that FGFR2 and FGFR3 are upregulated during wound healing or infection, this could be a reason why higher levels are observed in TLR2 KO microglia. FGRF2 and FGRF3 are key regulators of neuronal protection and repair following brain injury/infection. Therefore, microglia may be increasing the expression of these receptors in an effort to control the damage that is occurring in response to the increased bacterial burden in TLR2 KO animals.https://digitalcommons.unmc.edu/surp2020/1000/thumbnail.jp
Protein sizing with Differential Dynamic Microscopy
Introduced more than fifty years ago, dynamic light scattering is routinely
used to determine the size distribution of colloidal suspensions, as well as of
macromolecules in solution, such as proteins, nucleic acids, and their
complexes. More recently, differential dynamic microscopy has been proposed as
a way to perform dynamic light scattering experiments with a microscope, with
much less stringent constraints in terms of cleanliness of the optical
surfaces, but a potentially lower sensitivity due to the use of camera-based
detectors. In this work, we push bright-field differential dynamic microscopy
beyond known limits and show it to be sufficiently sensitive to size small
macromolecules in diluted solutions. By considering solutions of three
different proteins (Bovine Serum Albumin, Lysozyme, and Pepsin), we accurately
determine the diffusion coefficient and hydrodynamic radius of both single
proteins and small protein aggregates down to concentrations of a few
milligrams per milliliter. In addition, we present preliminary results showing
unexplored potential for the determination of virial coefficients. Our results
are in excellent agreement with the ones obtained in parallel with a
state-of-the-art commercial dynamic light scattering setup, showing that
differential dynamic microscopy represents a valuable alternative for rapid,
label-free protein sizing with an optical microscope
An investigation into reinforced and functionally graded lattice structures
Lattice structures are regarded as excellent candidates for use in lightweight energy absorbing applications, such as crash protection. In this paper we investigate the crushing behaviour, mechanical properties and energy absorption of lattices made by an additive manufacturing (AM) process. Two types of lattice were examined; body-centred-cubic (BCC) and a reinforced variant called BCCz. The lattices were subject to compressive loads in two orthogonal directions, allowing an assessment of their mechanical anisotropy to be made. We also examined functionally graded versions of these lattices, which featured a density gradient along one direction. The graded structures exhibited distinct crushing behaviour, with a sequential collapse of cellular layers preceding full densification. For the BCCz lattice, the graded structures were able to absorb around 114% more energy per unit volume than their non-graded counterparts before full densification, 1371 +or- 9 kJ/m3 vs. 640 +or- 10 kJ/m3. This highlights the strong potential for functionally graded lattices to be used in energy absorbing applications. Finally, we determined several of the Gibson-Ashby coefficients relating the mechanical properties of lattice structures to their density; these are crucial in establishing the constitutive models required for effective lattice design. These results improve the current understanding of AM lattices, and will enable the design of sophisticated, functional, lightweight components in the future
Recommended from our members
Evidence of Molecular Evolution Driven by Recombination Events Influencing Tropism in a Novel Human Adenovirus that Causes Epidemic Keratoconjunctivitis
In 2005, a human adenovirus strain (formerly known as HAdV-D22/H8 but renamed here HAdV-D53) was isolated from an outbreak of epidemic keratoconjunctititis (EKC), a disease that is usually caused by HAdV-D8, -D19, or -D37, not HAdV-D22. To date, a complete change of tropism compared to the prototype has never been observed, although apparent recombinant strains of other viruses from species Human adenovirus D (HAdV-D) have been described. The complete genome of HAdV-D53 was sequenced to elucidate recombination events that lead to the emergence of a viable and highly virulent virus with a modified tropism. Bioinformatic and phylogenetic analyses of this genome demonstrate that this adenovirus is a recombinant of HAdV-D8 (including the fiber gene encoding the primary cellular receptor binding site), HAdV-D22, (the ε determinant of the hexon gene), HAdV-D37 (including the penton base gene encoding the secondary cellular receptor binding site), and at least one unknown or unsequenced HAdV-D strain. Bootscanning analysis of the complete genomic sequence of this novel adenovirus, which we have re-named HAdV-D53, indicated at least five recombination events between the aforementioned adenoviruses. Intrahexon recombination sites perfectly framed the ε neutralization determinant that was almost identical to the HAdV-D22 prototype. Additional bootscan analysis of all HAdV-D hexon genes revealed recombinations in identical locations in several other adenoviruses. In addition, HAdV-D53 but not HAdV-D22 induced corneal inflammation in a mouse model. Serological analysis confirmed previous results and demonstrated that HAdV-D53 has a neutralization profile representative of the ε determinant of its hexon (HAdV-D22) and the fiber (HAdV-D8) proteins. Our recombinant hexon sequence is almost identical to the hexon sequences of the HAdV-D strain causing EKC outbreaks in Japan, suggesting that HAdV-D53 is pandemic as an emerging EKC agent. This documents the first genomic, bioinformatic, and biological descriptions of the molecular evolution events engendering an emerging pathogenic adenovirus
Solid Electrolyte Interphase Formation on Silicon and Lithium Titanate Anodes in Lithium-Ion Batteries
To gain new insights into the formation of the solid electrolyte interphase (SEI), as a basis for the safe and efficient use of new anode materials, we studied SEI formation on silicon and lithium titanate (LTO) anodes by electrochemical impedance spectroscopy (EIS) and ex situ X-ray photoelectron spectroscopy (XPS) measurements. While EIS measurements performed at equidistant voltage intervals provided insights into the SEI formation process, ex situ X-ray photoelectron spectroscopy (XPS) measurements supplied data on the chemical composition of the SEI layer. On silicon anodes we observed that resistance decreases in the second cycle which suggests the formation of a stable SEI with SiO2, Li4SiO4, LiF and different carbonates as its main components. On LTO anodes, however, resistance increases by a factor of two indicating incomplete SEI formation. Here LiF and different carbonates were identified as the SEI’s main components
AircraftVerse: A Large-Scale Multimodal Dataset of Aerial Vehicle Designs
We present AircraftVerse, a publicly available aerial vehicle design dataset.
Aircraft design encompasses different physics domains and, hence, multiple
modalities of representation. The evaluation of these cyber-physical system
(CPS) designs requires the use of scientific analytical and simulation models
ranging from computer-aided design tools for structural and manufacturing
analysis, computational fluid dynamics tools for drag and lift computation,
battery models for energy estimation, and simulation models for flight control
and dynamics. AircraftVerse contains 27,714 diverse air vehicle designs - the
largest corpus of engineering designs with this level of complexity. Each
design comprises the following artifacts: a symbolic design tree describing
topology, propulsion subsystem, battery subsystem, and other design details; a
STandard for the Exchange of Product (STEP) model data; a 3D CAD design using a
stereolithography (STL) file format; a 3D point cloud for the shape of the
design; and evaluation results from high fidelity state-of-the-art physics
models that characterize performance metrics such as maximum flight distance
and hover-time. We also present baseline surrogate models that use different
modalities of design representation to predict design performance metrics,
which we provide as part of our dataset release. Finally, we discuss the
potential impact of this dataset on the use of learning in aircraft design and,
more generally, in CPS. AircraftVerse is accompanied by a data card, and it is
released under Creative Commons Attribution-ShareAlike (CC BY-SA) license. The
dataset is hosted at https://zenodo.org/record/6525446, baseline models and
code at https://github.com/SRI-CSL/AircraftVerse, and the dataset description
at https://aircraftverse.onrender.com/.Comment: The dataset is hosted at https://zenodo.org/record/6525446, baseline
models and code at https://github.com/SRI-CSL/AircraftVerse, and the dataset
description at https://aircraftverse.onrender.com
Cohort profile: the Swiss Cerebral Palsy Registry (Swiss-CP-Reg) cohort study.
BACKGROUND
Cerebral Palsy (CP) is a group of permanent disorders of movement and posture that follow injuries to the developing brain. It results in motor dysfunction and a wide variety of comorbidities like epilepsy; pain; speech, hearing and vision disorders; cognitive dysfunction; and eating and digestive difficulties. Central data collection is essential to the study of the epidemiology, clinical presentations, care, and quality of life of patients affected by CP. CP specialists founded the Swiss Cerebral Palsy Registry (Swiss-CP-Reg) in 2017. This paper describes the design, structure, aims and achievements of Swiss-CP-Reg and presents its first results.
METHODS
Swiss-CP-Reg records patients of any age diagnosed with CP who are born, are treated, or live in Switzerland. It collects data from medical records and reports, from questionnaires answered by patients and their families, and from data linkage with routine statistics and other registries. The registry contains information on diagnosis, clinical presentation, comorbidities, therapies, personal information, family history, and quality of life.
RESULTS
From August 2017 to August 2021, 546 participants (55% male, mean age at registration 8 years [interquartile range IQR: 5-12]), were enrolled in Swiss-CP-Reg. Most had been born at term (56%), were less than two years old at diagnosis (73%, median 18 months, IQR: 9-25), and were diagnosed with spastic CP (76%). Most (59%) live with a mild motor impairment (Gross Motor Function Classification System [GMFCS] level I or II), 12% with a moderate motor impairment (GMFCS level III), and 29% with a severe motor impairment (GMFCS level IV or V). In a subset of 170 participants, we measured intelligence quotient (IQ) and saw lower IQs with increasing GMFCS level. Swiss-CP-Reg has a strong interest in research, with four nested projects running currently, and many more planned.
CONCLUSIONS
Swiss-CP-Reg collects and exchanges national data on people living with CP to answer clinically relevant questions. Its structure enables retrospective and prospective data collection and knowledge exchange between experts to optimise and standardise treatment and to improve the health and quality of life of those diagnosed with CP in Switzerland
- …