Abstract
Adolescence is a formative period for socio-emotional development which is threatened by the COVID-19 pandemic. The current longitudinal study examined two aims: (1) the short- and long-term ...effects of the pandemic on young people’s mood (i.e. vigor, tension, and depression levels) and emotional reactivity (i.e. fluctuations in daily mood), and (2) the impact of stressors on mood, emotional reactivity, self-oriented (i.e. maladaptive behavior towards COVID-19 rules) and other-benefitting behaviors (i.e. behavior aimed at helping and comforting others). We conducted an online two-week daily diary study among 462 Dutch adolescents (
M
age
= 15.27 years, 64% females) and 371 young adults (
M
age
= 21.49 years, 81% females) in May 2020, with a follow-up in November 2020 (
N
= 238 and 231, respectively adolescents and young adults). In May 2020, young adults and older relative to younger adolescents showed higher levels and more fluctuations in tension and depression and lower levels of vigor. Vigor levels decreased and tension and depression levels increased between May 2020 and November 2020, especially for younger adolescents. There were positive associations between instability of negative emotions (i.e. tension and depression fluctuations) and the exposure to stressors (i.e. family stress and inequality of online homeschooling) in the adolescent sample. Together, this study demonstrates vulnerability regarding young people’s mood and emotional reactivity during the COVID-19 pandemic, especially for adolescents who experience more stressors.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
In this work, the exceptionally improved sensing capability of highly porous three-dimensional (3-D) hybrid ceramic networks toward reducing gases is demonstrated for the first time. The 3-D hybrid ...ceramic networks are based on doped metal oxides (Me x O y and Zn x Me1–x O y , Me = Fe, Cu, Al) and alloyed zinc oxide tetrapods (ZnO-T) forming numerous junctions and heterojunctions. A change in morphology of the samples and formation of different complex microstructures is achieved by mixing the metallic (Fe, Cu, Al) microparticles with ZnO-T grown by the flame transport synthesis (FTS) in different weight ratios (ZnO-T:Me, e.g., 20:1) followed by subsequent thermal annealing in air. The gas sensing studies reveal the possibility to control and change/tune the selectivity of the materials, depending on the elemental content ratio and the type of added metal oxide in the 3-D ZnO-T hybrid networks. While pristine ZnO-T networks showed a good response to H2 gas, a change/tune in selectivity to ethanol vapor with a decrease in optimal operating temperature was observed in the networks hybridized with Fe-oxide and Cu-oxide. In the case of hybridization with ZnAl2O4, an improvement of H2 gas response (to ∼7.5) was reached at lower doping concentrations (20:1), whereas the increase in concentration of ZnAl2O4 (ZnO-T:Al, 10:1), the selectivity changes to methane CH4 gas (response is about 28). Selectivity tuning to different gases is attributed to the catalytic properties of the metal oxides after hybridization, while the gas sensitivity improvement is mainly associated with additional modulation of the electrical resistance by the built-in potential barriers between n-n and n-p heterojunctions, during adsorption and desorption of gaseous species. Density functional theory based calculations provided the mechanistic insights into the interactions between different hybrid networks and gas molecules to support the experimentally observed results. The studied networked materials and sensor structures performances would provide particular advantages in the field of fundamental research, applied physics studies, and industrial and ecological applications.
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IJS, KILJ, NUK, PNG, UL, UM
Calcite-water interactions are important not only in carbon sequestration and the global carbon cycle, but also in contaminant behaviour in calcite-bearing host rock and in many industrial ...applications. Here we quantify the effect of variations in surface structure on calcite surface reactivity. Firstly, we employ classical Molecular Dynamics simulations of calcite surfaces containing an etch pit and a growth terrace, to show that the local environment in water around structurally different surface sites is distinct. In addition to observing the expected formation of more calcium-water interactions and hydrogen-bonds at lower-coordinated sites, we also observed subtle differences in hydrogen bonding around acute versus obtuse edges and corners. We subsequently used this information to refine the protonation constants for the calcite surface sites, according to the Charge Distribution MUltiSite Ion Complexation (CD-MUSIC) approach. The subtle differences in hydrogen bonding translate into markedly different charging behaviour versus pH, in particular for acute versus obtuse corner sites. The results show quantitatively that calcite surface reactivity is directly related to surface topography. The information obtained in this study is not only crucial for the improvement of existing macroscopic surface models of the reactivity of calcite towards contaminants, but also improves our atomic-level understanding of mineral-water interactions.
The control of nanoparticle shape offers promise for improving catalytic activity and selectivity through optimization of the structure of the catalytically active site. Here, we have employed ...density functional theory calculations with a correction for the long-range interactions (DFT-D2) to investigate the effect of adsorption of the amino acid cysteine on the {001}, {011}, {100}, and {111} surfaces of mackinawite, which are commonly found in FeS nanoparticles. We have calculated the surface energies and adsorption energies for all the surfaces considered, and compared the surface energies of the pure and adsorbed systems. Based on the calculated surface energies, we have simulated the thermodynamic crystal morphology of the pure and cysteine-modified FeS nanoparticles using Wulff's construction. The strength of cysteine adsorption is found to be related to the stability of different surfaces, where it adsorbs most strongly onto the least stable FeS{111} surface
via
bidentate Fe-S and Fe-N chemical bonds and most weakly onto the most stable FeS{001} surface
via
hydrogen-bonded interactions; the adsorption energy decreases in the order {111} > {100} > {011} > {001}. We demonstrate that the stronger binding of the cysteine to the {011}, {100}, and {111} surfaces rather than to the {001} facet results in shape modulation of the FeS nanoparticles, with the reactive surfaces more expressed in the thermodynamic crystal morphology compared to the unmodified FeS crystals. Information regarding the structural parameters, electronic structures and vibrational frequency assignments of the cysteine-FeS complexes is also presented.
The surface and shape modulation of mackinawite (FeS) nanoparticles by amino acid cysteine adsorption is investigated using a first-principles density functional theory calculations, corrected for dispersion-interactions (DFT-D2).
Abstract
Background
Emerging evidence suggests survival benefit from resection beyond all MRI abnormalities present on T1-enhanced and T2‒fluid attenuated inversion recovery (FLAIR) modalities in ...glioma (supratotal resection); however, the quality of evidence is unclear. We addressed this question via systematic review of the literature.
Methods
EMBASE, MEDLINE, Scopus, and Web of Science databases were queried. Case studies, reviews or editorials, non-English, abstract-only, brain metastases, and descriptive works were excluded. All others were included.
Results
Three hundred and nine unique references yielded 41 studies for full-text review, with 7 included in the final analysis. Studies were mostly of Oxford Center for Evidence-Based Medicine Level 4 quality. A total of 88 patients underwent supratotal resection in a combined cohort of 492 patients (214 males and 278 females, age 18 to 82 years). Fifty-one supratotal resections were conducted on high-grade gliomas, and 37 on low-grade gliomas. Karnofsky performance status, overall survival, progression-free survival, neurological deficits postoperatively, and anaplastic transformation were the main measured outcomes. No randomized controlled trials were identified. Preliminary low-quality support was found for supratotal resection in increasing overall survival and progression-free survival for both low-grade and high-grade glioma.
Conclusion
The literature suggests insufficient evidence for carte blanche application of supratotal resection, particularly in lower-grade gliomas where neurological deficits can result in long-term disability. While the preliminary studies discussed here, containing data from only a few centers, have reported increased progression-free and overall survival, these claims require validation in prospective research studies involving larger patient populations with clearly defined appropriate outcome metrics in order to reduce potential bias.
We have conducted first-principles and classical molecular dynamics simulations of various compositions of strontium-containing phosphate glasses, to understand how strontium incorporation will ...change the glasses’ activity when implanted into the body (bioactivity). To perform the classical simulations, we have developed a new interatomic potential, which takes account of the polarizability of the oxygen ions. The Sr–O bond length is ∼2.44–2.49 Å, and the coordination number is 7.5–7.8. The Q
n
distribution and network connectivity were roughly constant for these compositions. Sr bonds to a similar number of phosphate chains as Ca does; based on our previous work (Christie et al. in J Phys Chem B 117:10652,
2013
), this implies that SrO ↔ CaO substitution will barely change the dissolution rate of these glasses and that the bioactivity will remain essentially constant. Strontium could therefore be incorporated into phosphate glass for biomedical applications.
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DOBA, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, IZUM, KILJ, KISLJ, MFDPS, NLZOH, NUK, OBVAL, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, SIK, UILJ, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
A methodology is presented, which reduces the number of site-occupancy configurations to be calculated when modelling site disorder in solids, by taking advantage of the crystal symmetry of the ...lattice. Within this approach, two configurations are considered equivalent when they are related by an isometric operation; a trial list of possible isometric transformations is provided by the group of symmetry operators in the parent structure, which is used to generate all configurations via atomic substitutions. We have adapted the equations for configurational statistics to operate in the reduced configurational space of the independent configurations. Each configuration in this space is characterized by its reduced energy, which includes not only its energy but also a contribution from its degeneracy in the complete configurational space, via an entropic term. The new computer program SOD (site-occupancy disorder) is presented, which performs this analysis in systems with arbitrary symmetry and any size of supercell. As a case study we use the distribution of cations in iron antimony oxide FeSbO4, where we also introduce some general considerations for the modelling of site-occupancy disorder in paramagnetic systems.
Non-enzymatic advanced glycation end product (AGE) cross-linking of collagen molecules has been hypothesised to result in significant changes to the mechanical properties of the connective tissues ...within the body, potentially resulting in a number of age related diseases. We have investigated the effect of two of these cross-links, glucosepane and DOGDIC, on the tensile and lateral moduli of the collagen molecule through the use of a steered molecular dynamics approach, using previously identified preferential formation sites for intra-molecular cross-links. Our results show that the presence of intra-molecular AGE cross-links increases the tensile and lateral Young’s moduli in the low strain domain by between 3.0–8.5% and 2.9–60.3% respectively, with little effect exhibited at higher strains.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
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