Many facets: A controlled synthesis results in high‐symmetry small‐molecular organic microcrystals with shapes that range from cubes through truncated cubes to rhombic dodecahedra (see picture). Morphological control was achieved by changes in solubility, which substantially alters the growth rate in the 〈100〉 direction relative to that in the 〈110〉 direction. Changes in morphology also lead to different optical properties of the crystals.

The nonenzymatic glycation of proteins by reducing sugars, also known as the Maillard reaction, has received increasing recognition from nutritional science and medical research. In this study, we applied matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) to perform relative and simultaneous quantification of the Amadori product, which is an early glycation product, and of N(epsilon)-(carboxymethyl)lysine and imidazolone A, two important advanced glycation end products. Therefore, native lysozyme was incubated with d-glucose for increasing periods of time (1, 4, 8, and 16 weeks) in phosphate-buffered saline pH 7.8 at 50 degrees C. After enzymatic digestion with endoproteinase Glu-C, the N-terminal peptide fragment (m/z 838; amino acid sequence KVFGRCE) and the C-terminal peptide fragment (m/z 1202; amino acid sequence VQAWIRGCRL) were used for relative quantification of the three Maillard products. Amadori product, N(epsilon)-(carboxymethyl)lysine, and imidazolone A were the main glycation products formed under these conditions. Their formation was dependent on glucose concentration and reaction time. The kinetics were similar to those obtained by competitive ELISA, an established method for quantification of N(epsilon)-(carboxymethyl)lysine and imidazolone A. Inhibition experiments showed that coincubation with N(alpha)-acetylargine suppressed formation of imidazolone A but not of the Amadori product or N(epsilon)-(carboxymethyl)lysine. The presence of N(alpha)-acetyllysine resulted in the inhibition of lysine modifications but in higher concentrations of imidazolone A. o-Phenylenediamine decreased the yield of the Amadori product and completely inhibited the formation of N(epsilon)-(carboxymethyl)lysine and imidazolone A. MALDI-TOF-MS proved to be a new analytical tool for the simultaneous, relative quantification of specific products of the Maillard reaction. For the first time, kinetic data of defined products on specific sites of glycated protein could be measured. This characterizes MALDI-TOF-MS as a valuable method for monitoring the Maillard reaction in the course of food processing.

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Colombo (2021) Effects of surfactants/ stabilizing agents on the microstructure and properties of porous geopolymers by direct foaming,

Objective: To explore the effects of self-directed learning readiness and learning attitude on problem-solving ability among Chinese undergraduate nursing students. Methods: A convenience sampling of 460 undergraduate nursing students was surveyed in Tianjin, China. Students who participated in the study completed a questionnaire that included social demographic questionnaire, Self-directed Learning Readiness Scale, Attitude to Learning Scale, and Social Problem-Solving Inventory. Pearson's correlation analysis was performed to test the correlations among problem-solving ability, self-directed learning readiness, and learning attitude. Hierarchical linear regression analyses were performed to explore the mediating role of learning attitude. Results: The results showed that learning attitude (r=0.338, P<0.01) and self-directed learning readiness (r=0.493, P<0.01) were positively correlated with problem-solving ability. Learning attitude played a partial intermediary role between self-directed learning readiness and problem-solving ability (F=74.227, P<0.01). Conclusions: It is concluded that nursing educators should pay attention on students' individual differences and take proper actions to inspire students' self-directed learning readiness and learning attitude.

Background: Aberrant static functional connectivity (FC) has been well demonstrated in amyotrophic lateral sclerosis (ALS); however, ALS-related alterations in FC dynamic properties remain unclear, although dynamic FC analyses contribute to uncover mechanisms underlying neurodegenerative disorders. Purpose: To explore dynamic functional network connectivity (dFNC) in ALS and its correlation with disease severity. Study Type: Prospective. Subjects: Thirty-two ALS patients and 45 healthy controls. Field Strength/Sequence: Multiband resting-state functional images using gradient echo echo-planar imaging and T1weighted images were acquired at 3.0 T. Assessment: Disease severity was evaluated with the revised ALS Functional Rating Scale (ALSFRS-R) and patients were stratified according to diagnostic category. Independent component analysis was conducted to identify the components of seven intrinsic brain networks (ie, visual/sensorimotor (SMN)/auditory/cognitive-control (CCN)/default-mode (DMN)/subcortical/cerebellar networks). A sliding-window correlation approach was used to compute dFNC. FNC states were determined by k-mean clustering, and state-specific FNC and dynamic indices (fraction time/mean dwell time/transition number) were calculated. Statistical Tests: Two-sample t test used for comparisons on dynamic measures and Spearman's correlation analysis. Results: ALS patients showed increased FNC between DMN-SMN in state 1 and between CCN-SMN in state 4. Patients remained in state 2 (showing the weakest FNC) for a significantly longer time (mean dwell time: 49.8 AE 40.1 vs. 93.6 AE 126.3; P < 0.05) and remained in state 1 (showing a relatively strong FNC) for a shorter time (fraction time: 0.27 AE 0.25 vs. 0.13 AE 0.20; P < 0.05). ALS patients exhibited less temporal variability in their FNC (transition number: 10.2 AE 4.4 vs. 7.8 AE 3.8; P < 0.05). A significant correlation was observed between ALSFRS-R and mean dwell time in state 2 (r = −0.414, P < 0.05) and transition number (r = 0.452, P < 0.05). No significant between-subgroup difference in dFNC properties was found (all P > 0.05). Data Conclusion: Our findings suggest aberrant dFNC properties in ALS, which is associated with disease severity. Level of Evidence: 2 Technical Efficacy: Stage 3

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