Background and purpose
The American Heart Association Life's Simple 7 (LS7) metric was used to define optimal cardiovascular and brain health, but the associations with macrostructural ...hyperintensities and microstructural white matter damage are unclear. The objective was to determine the association of LS7 ideal cardiovascular health factors with macrostructural and microstructural integrity.
Method
A total of 37,140 participants with available LS7 and imaging data from UK Biobank were included in this study. Linear associations were implemented to examine the associations of LS7 score and subscores with white matter hyperintensity load (WMH) (WMH volume normalized by total white matter volume and logit‐transformed) and diffusion imaging indices (fractional anisotropy FA, mean diffusivity, orientation dispersion index OD, intracellular volume fraction, isotropic volume fraction ISOVF).
Results
In individuals (mean age 54.76 years; 19,697 females, 52.4%), higher LS7 score and subscores were strongly associated with lower WMH and microstructural white matter injury, including OD, ISOVF, FA. Both interaction analyses and stratified analyses of LS7 score and subscores with age and sex showed a strong association with microstructural damage markers, with remarkable age and sex differences. The association of OD was pronounced in females and populations younger than 50 years and FA, mean diffusivity and ISOVF were pronounced in males and populations older than 50 years.
Conclusion
These findings suggest that healthier LS7 profiles are associated with better profiles of both macrostructural and microstructural markers of brain health, and indicate that ideal cardiovascular health is associated with improved brain health.
Virtual reality (VR) is the use of computer technology to create an interactive three-dimensional (3D) world, which gives users a sense of spatial presence. In nursing education, VR has been used to ...help optimize teaching and learning processes.
The purpose of this study was to evaluate the effectiveness of VR in nursing education in the areas of knowledge, skills, satisfaction, confidence, and performance time.
We conducted a meta-analysis of the effectiveness of VR in nursing education based on the Cochrane methodology. An electronic literature search using the Cochrane Library, Web of Science, PubMed, Embase, and CINAHL (Cumulative Index to Nursing and Allied Health Literature), up to December 2019 was conducted to identify studies that reported the effectiveness of VR on knowledge, skills, satisfaction, confidence, and performance time. The study selection and data extraction were carried out by two independent reviewers. The methodological quality of the selected studies was determined using the Cochrane criteria for risk-of-bias assessment.
A total of 12 studies, including 821 participants, were selected for the final analysis. We found that VR was more effective than the control conditions in improving knowledge (standard mean difference SMD=0.58, 95% CI 0.41-0.75, P<.001, I
=47%). However, there was no difference between VR and the control conditions in skills (SMD=0.01, 95% CI -0.24 to 0.26, P=.93, I
=37%), satisfaction (SMD=0.01, 95% CI -0.79 to 0.80, P=.99, I
=86%), confidence (SMD=0.00, 95% CI -0.28 to 0.27, P=.99, I
=0%), and performance time (SMD=-0.55, 95% CI -2.04 to 0.94, P=.47, I
=97%).
The results of this study suggest that VR can effectively improve knowledge in nursing education, but it was not more effective than other education methods in areas of skills, satisfaction, confidence, and performance time. Further rigorous studies with a larger sample size are warranted to confirm these results.
The unique structure and reactivity of the aziridine ring has attracted the interest of organic chemists for many years. Of these, the cycloaddition of alkynes with aziridines via C–C bond and C–N ...bond cleavage is an atom-efficient and convergent approach to the preparation of valuable unsaturated N-heterocycles. In this Perspective, progress in this field is outlined on the basis of the key intermediate involved in the reaction. In addition to the cycloadditions of azomethine ylides generated by carbon–carbon bond cleavage and aziridinium ions and zwitterionic 1,3-dipoles generated by carbon–nitrogen bond cleavage, the new type of cycloadditions of aziridines and alkynes involving metalla-azetidine intermediates has been highlighted in this short review. The use of methyleneaziridine in the cycloaddition reactions with alkynes is also discussed. Contrary to noncatalytic cycloadditions of aziridines with alkynes via azomethine ylides or aziridinium ions, the catalytic cycloadditions for synthesis of unsaturated N-heterocycles from aziridines and alkynes have more opportunity to improve the efficiency and selectivity of the reaction and to expand their synthetic utility.
A new synthetic application of vinyl aziridines as N‐containing three‐atom components in a rhodium‐catalyzed 4+3 cycloaddition reaction is described. The reaction proceeds well with various silyl ...dienol ethers and vinyl aziridines, and enables the efficient synthesis of highly functionalized azepines in an enantioselective manner with net inversion of absolute configuration. The salient features of the transformation include the use of readily available substrates, high selectivity, and mild reaction conditions, as well as the versatile functionalization of the products.
Strike a happy medium: The title reaction, in which the vinyl aziridine acts as an aza‐three‐atom component, provided highly functionalized azepines in an enantioselective manner with net inversion of configuration (see scheme; Si is a silyl protecting group). This strategy features the use of readily available substrates, high selectivity, mild reaction conditions, ease of scale‐up, and versatile functionalization of the products.
Self-reinforced lithium disilicate (Li
2
Si
2
O
5
, LD) glass-ceramics were hot pressing sintered by introducing 5 wt% Li
2
Si
2
O
5
crystal seeds into two different glass compositions of SiO
2
-Li
2
...O-P
2
O
5
-ZrO
2
-Al
2
O
3
-K
2
O-La
2
O
3
(7C LD) and SiO
2
-Li
2
O-K
2
O-La
2
O
3
(4C LD). The results show that the seeds play an important role in the crystallization inducement, and microstructural and property improvement of the glass, especially for the glass powder without the nucleating agent of P
2
O
5
. The microstructure features a wider bimodal grain size distribution with large rod-like crystals epitaxially grown along the seeds and small crystals nucleated from the glass powder itself, contributing to the improvement of the performance especially the fracture toughness. The specimen of 4C LD glass with the addition of 5 wt% Li
2
Si
2
O
5
seeds exhibited the best comprehensive properties with a good flexural strength (396±7 MPa), improved fracture toughness (3.31±0.19 MPa·m
1/2
), and comparable translucency as IPS e.max. This research provides a new idea and method for the improvement of the fracture toughness of lithium disilicate glass-ceramics without affecting its aesthetic appearance, and lays the foundation for its clinical applications.
Modern engineering alloys contain multiple alloying elements, but their direct observation when segregated at the atomic scale is challenging because segregation is susceptible to electron beam ...damage. This is very severe for magnesium alloys, especially when solute atoms segregate to form single atomic columns. Here we show that we can image segregation in magnesium alloys with atomic-resolution X-ray dispersive spectroscopy at a much lower electron voltage. We report a co-segregation pattern at twin boundaries in a magnesium alloy with both larger and smaller solutes forming alternating columns that fully occupy the twin boundary, in contrast to previous observations of half occupancy where mixed-solute columns alternate with magnesium. We further show that the solute co-segregation affects the twin migration mechanism and increases the twin boundary pinning. Our work demonstrates that the atomic-scale analysis of the structure and chemistry of solute segregation in metallic alloys with complex compositions is now possible.
Interface engineering has been proved to be an efficient strategy for boosting electrocatalytic performance and has attracted increasing interest in past few decades. Herein, Co
3
O
4
@LaCoO
3
...heterojunctions with abundant oxygen vacancies, subtle lattice distortion, and atomic-level coupled interfaces were synthesized in a nonequilibrium stoichiometric ratio. The synthesized product shows exceptional bifunctional catalytic activity and robust stability in the oxygen evolution reaction (OER) and oxygen reduction reaction (ORR). As demonstrated by high-resolution transmission electron microscopy (HRTEM), X-ray photoelectron spectroscopy (XPS), and extended X-ray absorption fine structure spectroscopy (XAFS), the heterojunction structure between Co
3
O
4
and LaCoO
3
was formed, which is beneficial for its electrocatalytic properties. The enhanced catalytic capacity is also evidenced by the results of experimental measurements and first-principles calculations. Furthermore, the Co
3
O
4
@LaCoO
3
assembled Zn-air batteries (including routine liquid batteries and flexible solid-type batteries) exhibit a large peak power density, high open-circuit potential, and a long-term cycle life. This work affords rational design strategies of spinel@perovskite dual-phase oxides and provides potential applications in wearable electronic devices.
The interfacial synergy of Co
3
O
4
@LaCoO
3
provides fast charge transfer paths and kinetics in the oxide/solution interface, which exhibit exceptional bifunctional catalytic activity and robust stability for Zn-air batteries.
Magnetic liquid marbles have recently attracted extensive attention for various potential applications. However, conventional liquid marbles based on iron oxide nanoparticles are opaque and ...inadequate for photo‐related applications. Herein, we report the first development of liquid marbles coated with magnetic lanthanide‐doped upconversion nanoparticles (UCNPs) that can convert near‐infrared light into visible light. Apart from their excellent magnetic and mechanical properties, which are attractive for repeatable tip opening and magnetically directed movements, the resultant UCNP‐based liquid marbles can act as ideal miniature reactors for photodynamic therapy of cancer cells. This work opens new ways for the development of liquid marbles, and shows great promise for liquid marbles based on UCNPs to be used in a large variety of potential applications, such as photodynamic therapy for accelerated drug screening, magnetically guided controlled drug delivery and release, and multifunctional actuation.
All rolled into one: Liquid marbles based on magnetic upconversion nanoparticles (UCNPs) exhibit excellent magnetic and mechanical properties and were used for the conversion of low‐energy near‐infrared photons into high‐energy UV/Vis photons. They might find application in photodynamic therapy as well as for magnetically controlled drug delivery and release and multifunctional actuation.
Summary
Microbe‐associated molecular pattern (MAMP)‐triggered immunity plays critical roles in the basal resistance defense response in plants. Chitin and peptidoglycan (PGN) are major molecular ...patterns for fungi and bacteria, respectively. Two rice (Oryza sativa) lysin motif‐containing proteins, OsLYP4 and OsLYP6, function as receptors that sense bacterial PGN and fungal chitin. These membrane receptors, which lack intracellular kinase domains, likely contain another component for transmembrane immune signal transduction. Here, we demonstrate that the rice LysM receptor‐like kinase OsCERK1, a key component of the chitin elicitor signaling pathway, also plays an important role in PGN‐triggered immunity in rice. Silencing of OsCERK1 suppressed PGN‐induced (and chitin‐induced) immunity responses, including reactive oxygen species generation, defense gene expression, and callose deposition, indicating that OsCERK1 is essential for both PGN and chitin signaling initiated by OsLYP4 and OsLYP6. OsLYP4 associated with OsLYP6 and the rice chitin receptor chitin oligosaccharide elicitor‐binding protein (CEBiP) in the absence of PGN or chitin, and treatment with PGN or chitin led to their disassociation in vivo. OsCERK1 associated with OsLYP4 or OsLYP6 when induced by PGN but it associated with OsLYP4, OsLYP6, or CEBiP under chitin treatment, suggesting the presence of different patterns of ligand‐induced heterooligomeric receptor complexes. Furthermore, the receptor‐like cytoplasmic kinase OsRLCK176 functions downstream of OsCERK1 in the PGN and chitin signaling pathways, suggesting that these MAMPs share overlapping intracellular signaling components. Therefore, OsCERK1 plays dual roles in PGN and chitin signaling in rice innate immunity and as an adaptor involved in signal transduction at the plasma membrane in conjunction with OsLYP4 and OsLYP6.
The structural and compositional evolution of precipitates in Al-Mg-Si-Cu alloys were systematically investigated by atomic resolution high-angle annular dark-field scanning transmission electron ...microscopy and atom probe tomography. In under-aged alloys, most of precipitates have a disordered structure, with a substructure of β″ (LDC) and Cu sub-unit cluster or C unit cell. After aging to peak strength, disordered precipitates including β″, QP1 and QP2 phases are formed. The disordered QP1 and QP2 phases, which contain the unit cells of Q′ and C phases, respectively, are the precursor phases of Q′ phase in these alloys. The β″ phase can transform into the disordered QP1 phase by incorporating Cu atoms, forming Cu sub-unit clusters and QP lattice. When the alloy is over-aged, the ordering and transformation of QP1 to Q′ occurs by the formation of Cu sub-unit clusters, the ordering of QP lattice, and the ordering of QC lattice. In contrast, the transformation of the disordered QP2 phase are rather sluggish. After sufficient aging, Q′, C and disordered QP2 transform into the Q phase. During the evolution of the precipitates in these alloys, a continuous incorporation of Mg, Si and Cu atoms and release of Al atoms occur. These findings provide new insights in understanding precipitation in Al-Mg-Si-Cu alloys.
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