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The notorious shuttling behaviors and sluggish conversion kinetics of the intermediate lithium polysulfides (LPS) are hindering the practical application of lithium sulfur (Li-S) batteries. Herein, an ultrafine, amorphous, and oxygen-deficient niobium pentoxide nanocluster embedded in microporous carbon nanospheres (A-Nb 2 O 5- x @MCS) was developed as a multifunctional sulfur immobilizer and promoter toward superior shuttle inhibition and conversion catalyzation of LPS. The A-Nb 2 O 5- x nanocluster implanted framework uniformizes sulfur distribution, exposes vast active interfaces, and offers a reduced ion/electron transportation pathway for expedited redox reaction. Moreover, the low crystallinity feature of A-Nb 2 O 5- x manipulates the LPS chemical affinity, while the defect chemistry enhances the intrinsic conductivity and catalytic activity for rapid electrochemical conversions. Attributed to these superiorities, A-Nb 2 O 5- x @MCS delivers good Li-S battery performances, that is, high areal capacity of 6.62 mAh cm -2 under high sulfur loading and low electrolyte/sulfur ratio, superb rate capability, and cyclability over 1200 cycles with an ultralow capacity fading rate of 0.024% per cycle. This work provides a synergistic regulation on crystallinity and oxygen deficiency toward rapid and durable sulfur electrochemistry, holding a great promise in developing practically viable Li-S batteries and enlightening material engineering in related energy storage and conversion areas.

Fruit set and development occur following successful fertilization. Parthenocarpy, a valuable trait in some self-incompatible species, produces seedless fruit without fertilization. Gibberellin (GA) is a crucial hormone in fruit-set regulation and development. While investigating the development of parthenocarpy in pear ( Pyrus bretschneideri Rehd.), we determined that GA 20-oxidases (GA20ox) may play key roles in seedless pear fruit development. Sequence analysis revealed three PbGA20ox genes: PbGA20ox1, PbGA20ox2 , and PbGA20ox3 . We analyzed the expression patterns of candidate genes and found that PbGA20ox2 levels significantly changed in pollinated fruits. Tissue-specific expression assays revealed that PbGA20ox2 is highly expressed in young fruit and leaves. Subcellular localization assays showed it was located in the cytoplasm, nucleus, and plasma membrane. Overexpressed PbGA20ox2 tomato plants were taller and had longer hypocotyls and internodes, and the emasculated flowers produced parthenocarpic fruit. In pear, the transient overexpression of PbGA20ox2 promoted fruit development and delayed the drop of nonpollinated fruit. Furthermore, the fruit of PbGA20ox2- overexpressing tomato and transient PbGA20ox2- overexpressing pear had increased GA 4 (but not GA 3 and GA 1 ) contents. This result provided evidence that PbGA20ox2 was necessary for GA 4 -dependent pear fruit development. Our study revealed that PbGA20ox2 altered the GA biosynthetic pathway and enhanced GA 4 synthesis, thereby promoting fruit set and parthenocarpic fruit development., (Copyright © 2020 Wang, Wu, Liu, Cong, Zhu, Zhai, Yang, Wang, Ma and Xu.)

Au 20 (PP 3 ) 4 Cl 4 (PP 3 =tris(2-(diphenylphosphino)ethyl) phosphine), abbreviated as Au 20 , is the only Au nanocluster with an intrinsically chiral core without a chiral environment (chiral ligands or Au-thiolate staples), making it a unique object to understand chiral evolution and explore chiral applications. Unfortunately, the synthesized Au 20 is racemic, and its enantiomers have not yet been separated. Herein, we report a supramolecular assembly strategy with α-cyclodextrin (α-CD) to afford enantiopure Au 20 in bulk, and an enantiomer excess (ee) value of as-separated Au 20 of 97 %. As a result of its high purity, the distinctive optical activity of Au 20 , which originates from electronic transitions confined in chiral cores, is fully explored. Theoretical studies reveals that the enantioseparation results from the preferential self-assembly of α-CD with organic ligands on the surface of right-handed Au 20 ., (© 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Chiral metal-organic framework (CMOF) nanosheets only a few layers thick remain a virgin land waiting for exploration. Herein, the first examples of ultrathin CMOF nanosheets are prepared by the confinement growth of two-dimensional (2D) chiral layers, which are assembled by helical metal-organic chains within microemulsion. This convenient and easily scaled up inverse microemulsion method gives a series of 2D CMOF nanosheets composed of variable metal nodes or chiral ligands. More significantly, thanks to the exceptionally large number of chiral sites exposed on surfaces, the as-obtained CMOF nanosheets exhibit much higher enantioselectivity in chiral separation compared with their bulk counterparts., (© 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Magnolol is a pharmacological biphenolic compound extracted from Chinese herb Magnolia officinalis, which displays anti-inflammatory and antioxidant effects. This study was aimed at exploring the potential effect of magnolol on immune-related liver fibrosis. Herein, BALB/c mice were injected with concanavalin A (ConA, 8 mg/kg/week) up to 6 weeks to establish hepatic fibrosis, and magnolol (10, 20, 30 mg/kg/day) was given to these mice orally throughout the whole experiment. We found that magnolol preserved liver function and attenuated liver fibrotic injury in vivo. In response to ConA stimulation, the CD4 + T cells preferred to polarizing towards CD4 + T helper 17 (Th17) cells in liver. Magnolol was observed to inhibit Th17 cell differentiation in ConA-treated liver in addition to suppressing interleukin (IL)-17A generation. Hepatic stellate cells were activated in fibrotic liver as demonstrated by increased alpha smooth muscle actin (α-SMA) and desmin. More transforming growth factor (TGF)-β1 and activin A were secreted into the serum. Magnolol suppressed this abnormal HSC activation. Furthermore, the phosphorylation of Smad3 in its linker area (Thr179, Ser 204/208/213) was inhibited by magnolol. In vitro, the recombinant IL-17A plus TGF-β1 or activin A induced activation of human LX2 HSCs and promoted their collagen production. Smad3/Smad4 signalling pathway was activated in LX2 cells exposed to the fibrotic stimuli, as illustrated by the up-regulated phospho-Smad3 and the enhanced interaction between Smad3 and Smad4. These alterations were suppressed by magnolol. Collectively, our study reveals a novel antifibrotic effect of magnolol on Th17 cell-mediated fibrosis., (© 2017 Nordic Association for the Publication of BCPT (former Nordic Pharmacological Society).)

Background: We studied the possible advantages of feed-forward control nursing model in the treatment of placenta previa., Methods: We enrolled 60 pregnant women who were receiving treatment for expectant placenta previa between January 2010 and January 2016 and randomly divided them into the control group and the observation group with 30 cases in each group. In the control group, we offered specialist nursing which included examination, body positioning, vaginal bleeding record, psychological consultation and medication observation. Feed-forward control nursing was applied in the observation group which included establishing feed-forward control nursing improvement team, conducting quality control of nursing defects and putting forward ideas for improvements and verifying improvement outcomes., Results: The observation group got significantly higher success rate and lower complication rate compared with control group. Gestational age and fetal weights improved apparently in the observation group. When we compared the amount of postpartum bleeding and pregnancy bleeding in two groups we did not find any statistically significant difference ( P >0.05). Patients' satisfaction rate toward our nursing services was much higher in the observation group and the rate of nursing errors was significantly lower in this group. All differences were statistically significant ( P <0.05)., Conclusion: Application of feed-forward control nursing model in the expectant treatment of placenta previa can improve treatment success rate, decrease complications and upgrade nursing quality.