For seeking high enantiopurity, the previously reported thermal asymmetric catalysis is usually carried out at low temperature sometimes with limited yield, that is, the high enantiomeric excess (ee) ...usually at the cost of high yield. Thus, the achieving both high stereoselectivity and yield is an enormous challenge. We report herein two metal nanoparticle (M NP)-loaded and porphyrin-containing homochiral covalent organic framework (CCOF)-based composite catalysts, and their application in the thermally-driven asymmetric one-pot Henry and A
-coupling reactions. All the reactions are conducted at elevated temperatures with both excellent stereoselectivity and yield which resulted from the synergy of CCOF confinement effect and M NP catalytic activation. Notably, the needed thermal energy for the asymmetric reactions herein is derived from the photothermal conversion via porphyrin-based CCOF upon irradiation with visible light. Remarkably, the CCOF confinement effect can be effectively maintained up to 100 °C for the asymmetric one-pot Henry and A
-coupling reactions herein.
Major depressive disorder (MDD) has been shown to be associated with structural abnormalities in a variety of spatially diverse brain regions. However, the correlation between brain structural ...changes in MDD and gene expression is unclear. Here, we examine the link between brain-wide gene expression and morphometric changes in individuals with MDD, using neuroimaging data from two independent cohorts and a publicly available transcriptomic dataset. Morphometric similarity network (MSN) analysis shows replicable cortical structural differences in individuals with MDD compared to control subjects. Using human brain gene expression data, we observe that the expression of MDD-associated genes spatially correlates with MSN differences. Analysis of cell type-specific signature genes suggests that microglia and neuronal specific transcriptional changes account for most of the observed correlation with MDD-specific MSN differences. Collectively, our findings link molecular and structural changes relevant for MDD.
Parkinson's disease (PD) is a neurodegenerative disorder with dysfunction in cortices as well as white matter (WM) tracts. While the changes to WM structure have been extensively investigated in PD, ...the nature of the functional changes to WM remains unknown. In this study, the regional activity and functional connectivity of WM were compared between PD patients (n = 57) and matched healthy controls (n = 52), based on multimodel magnetic resonance imaging data sets. By tract‐based spatial statistical analyses of regional activity, patients showed decreased structural‐functional coupling in the left corticospinal tract compared to controls. This tract also displayed abnormally increased functional connectivity within the left post‐central gyrus and left putamen in PD patients. At the network level, the WM functional network showed small‐worldness in both controls and PD patients, yet it was abnormally increased in the latter group. Based on the features of the WM functional connectome, previously un‐evaluated individuals could be classified with fair accuracy (73%) and area under the curve of the receiver operating characteristics (75%). These neuroimaging findings provide direct evidence for WM functional changes in PD, which is crucial to understand the functional role of fiber tracts in the pathology of neural circuits.
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Graphene quantum dots (GQDs) that are flat 0D nanomaterials have attracted increasing interest because of their exceptional chemicophysical properties and novel applications in energy conversion and ...storage, electro/photo/chemical catalysis, flexible devices, sensing, display, imaging, and theranostics. The significant advances in the recent years are summarized with comparative and balanced discussion. The differences between GQDs and other nanomaterials, including their nanocarbon cousins, are emphasized, and the unique advantages of GQDs for specific applications are highlighted. The current challenges and outlook of this growing field are also discussed.
Graphene quantum dots (GQDs) are flat 0D nanomaterials, promising a wide spectrum of applications. The recent significant advances are summarized with comparative, balanced, and mechanistic discussion. The difference between GQDs and other nanomaterials, and the unique advantages of GQDs for specific applications are highlighted. The current challenges and outlook of this growing field are also discussed.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Owing to their permanent porosity, highly ordered and extended structure, good chemical stability, and tunability, covalent organic frameworks (COFs) have emerged as a new type of organic materials ...that can offer various applications in different fields. Benefiting from the huge database of organic reactions, the required functionality of COFs can be readily achieved by modification of the corresponding organic functional groups on either polymerizable monomers or established COF frameworks. This striking feature allows homochiral covalent organic frameworks (HCCOFs) to be reasonably designed and synthesized, as well as their use as a unique platform to fabricate asymmetric catalysts. This contribution provides an overview of new progress in HCCOF‐based asymmetric catalysis, including design, synthesis, and their application in asymmetric organic synthesis. Moreover, major challenges and developing trends in this field are also discussed. It is anticipated that this review article will provide some new insights into HCCOFs for heterogeneous asymmetric catalysis and help to encourage further contributions in this young but promising field.
Chirality from COFs: Owing to their permanent porosity, highly ordered and extended structure, good chemical stability, and tunability, covalent organic frameworks have emerged as a new type of organic materials that can offer various applications in different fields. Herein, the design and synthesis of chiral covalent organic frameworks and their applications in asymmetric catalysis are highlighted.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Postsynthetic modification (PSM) has been demonstrated to be a powerful method for achieving new covalent organic frameworks (COFs) via single-step or multistep organic functional group ...transformations on established COF frameworks. PSM, however, might sometimes lead to collapse of the COF framework, decreases in crystallinity, or low postsynthetic yield due to the inherent limit of solid-state synthesis. Herein we report, for the first time, a new synthetic strategy that can generate new COFs via multicomponent one-pot in situ reactions. In total, 12 α-aminonitrile- and quinoline-linked COFs with high crystallinity and permanent porosity are successfully achieved by three-component one-pot in situ Strecker and Povarov reactions under solvothermal conditions in high yields. The obtained COFs feature the same structures as those obtained from the stepwise PSM approach on an established imine-linked COF. This in situ multicomponent assembly strategy, as a synthetic methodology parallel to PSM, might open a new route for constructing COFs that is not possible under PSM conditions.
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IJS, KILJ, NUK, PNG, UL, UM
(S)-2-(2-Chlorophenyl)-2-(6,7-dihydrothieno3,2-cpyridin-5(4H)-yl)acetonitrile ((S)-CIK) is a key intermediate in the synthesis of (S)-clopidogrel, which is one of the most saleable worldwide ...antiplatelet and antithrombotic drugs. We show herein a facile method for the direct synthesis of (S)-CIK via Strecker reaction using a homochiral covalent framework catalyst in a heterogeneous way. The asymmetric synthesis involves a photothermal-conversion-triggered, thermally driven reaction which affords (S)-CIK in 98% yield with 94% enantiomeric excess under visible-light irradiation. Furthermore, the above approach is readily extended to a gram-scale level on a fixed-bed continuous-flow model reactor. The potential utility of this strategy is highlighted by the preparation of many more other types of chiral drugs and drug intermediates in a green and facile way.
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IJS, KILJ, NUK, PNG, UL, UM
Repetitive transcranial magnetic stimulation (rTMS) is a noninvasive neuromodulation technique with great potential in the treatment of Parkinson's disease (PD). This study aimed to investigate the ...clinical efficacy of accelerated rTMS and to understand the underlying neural mechanism. In a double‐blinded way, a total of 42 patients with PD were randomized to receive real (n = 22) or sham (n = 20) continuous theta‐burst stimulation (cTBS) on the left supplementary motor area (SMA) for 14 consecutive days. Patients treated with real cTBS, but not with sham cTBS, showed a significant improvement in Part III of the Unified PD Rating Scale (p < .0001). This improvement was observed as early as 1 week after the start of cTBS treatment, and maintained 8 weeks after the end of the treatment. These findings indicated that the treatment response was swift with a long‐lasting effect. Imaging analyses showed that volume of the left globus pallidus (GP) increased after cTBS treatment. Furthermore, the volume change of GP was mildly correlated with symptom improvement and associated with the baseline fractional anisotropy of SMA‐GP tracts. Together, these findings implicated that the accelerated cTBS could effectively alleviate motor symptoms of PD, maybe by modulating the motor circuitry involving the SMA‐GP pathway.
An accelerated continuous theta‐burst stimulation protocol significantly alleviates motor symptoms in Parkinson's disease. Symptom improvement can be observed as early as 1 week after the start of treatment, and maintained 8 weeks after the end of treatment. Gray matter volume in the globus pallidus (GP) increased after treatment, and the increment was positively correlated with symptom improvement as well as baseline supplementary motor area‐GP structural connectivity.
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Thrips are tiny insects from the order Thysanoptera (Hexapoda: Condylognatha), including many sap‐sucking pests that are causing increasing damage to crops worldwide. In contrast to their closest ...relatives of Hemiptera (Hexapoda: Condylognatha), including numerous sap‐sucking species, there are few genomic resources available for thrips. In this study, we assembled the first thrips genome at the chromosomal level from the melon thrips, Thrips palmi, a notorious pest in agriculture, using PacBio long‐read and Illumina short‐read sequences. The assembled genome was 237.85 Mb in size, with 1,324 contigs and a contig N50 of 567 kb. All contigs were assembled into 16 linkage groups assisted by the Hi‐C technique. In total, 16,333 protein‐coding genes were predicted, of which 88.13% were functionally annotated. Among sap‐sucking insects, polyphagous species (e.g., T. palmi and Bemisia tabaci) usually possess more detoxification genes than oligophagous species (e.g., Diaphorina citri). The polyphagous thrips genomes characterized so far have relatively more detoxification genes in the GST and CCE families than polyphagous aphids, but they have fewer UGTs. HSP genes, especially from the Hsp70s group, have expanded in thrips compared to other hemipterans. These differences point to different genetic mechanisms associated with detoxification and stress responses in these two groups of sap‐sucking insects. The expansion of these gene families may contribute to the rapid development of pesticide resistance in thrips, as supported by a transcriptome comparison of resistant and sensitive populations of T. palmi. The high‐quality genome developed here provides an invaluable resource for understanding the ecology, genetics, and evolution of thrips as well as their relatives more generally.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Magnetic personality: The incorporation of a bulky auxiliary ligand in β‐diketone‐based dysprosium(III) single‐ion magnets (SIMs) remarkably increases the anisotropic barriers, representing a ...promising route toward the design of higher‐anisotropic‐barrier SIMs (see scheme).
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
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