Herein, we explore how OH groups on Pt/γ‐AlOOH and Pt/γ‐Al2O3 catalysts affect CO2 hydrogenation with H2 at temperatures from 250°C to 400°C. OH groups are abundant on γ‐AlOOH, but rare at ...Pt‐(γ‐AlOOH) interface which is the most favorable site for CO2 conversion on Pt/γ‐AlOOH. This makes CO2 hydrogenation on Pt/γ‐AlOOH form CO weakly bonding to γ‐AlOOH, which prefers to desorption from Pt/γ‐AlOOH rather than further conversion, thus enhancing CO production on Pt/γ‐AlOOH. Different from Pt/γ‐AlOOH, OH groups are abundant at Pt‐(γ‐Al2O3) interface which is the most favorable site for CO2 conversion on Pt/γ‐Al2O3. This promotes CO2 hydrogenation on Pt/γ‐Al2O3 to form CO strongly bonding to Pt, which prefers to further hydrogenation to CH4, and thereby increases CH4 selectivity on Pt/γ‐Al2O3. Therefore, the OH groups at metal‐support interface are crucial factor influencing product distribution, and must be considered seriously when fabricating catalysts.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
Cartilage injury and pathological degeneration are reported in millions of patients globally. Cartilages such as articular hyaline cartilage are characterized by poor self-regeneration ability due to ...lack of vascular tissue. Current treatment methods adopt foreign cartilage analogue implants or microfracture surgery to accelerate tissue repair and regeneration. These methods are invasive and are associated with the formation of fibrocartilage, which warrants further exploration of new cartilage repair materials. The present study aims to develop an injectable modified gelatin hydrogel.
The hydrogel effectively adsorbed proteoglycans secreted by chondrocytes adjacent to the cartilage tissue in situ, and rapidly formed suitable chondrocyte survival microenvironment modified by ε-poly-L-lysine (EPL). Besides, dynamic covalent bonds were introduced between glucose and phenylboronic acids (PBA). These bonds formed reversible covalent interactions between the cis-diol groups on polyols and the ionic boronate state of PBA. PBA-modified hydrogel induced significant stress relaxation, which improved chondrocyte viability and cartilage differentiation of stem cells. Further, we explored the ability of these hydrogels to promote chondrocyte viability and cartilage differentiation of stem cells through chemical and mechanical modifications.
In vivo and in vitro results demonstrated that the hydrogels exhibited efficient biocompatibility. EPL and PBA modified GelMA hydrogel (Gel-EPL/B) showed stronger activity on chondrocytes compared to the GelMA control group. The Gel-EPL/B group induced the secretion of more extracellular matrix and improved the chondrogenic differentiation potential of stem cells. Finally, thus hydrogel promoted the tissue repair of cartilage defects.
Modified hydrogel is effective in cartilage tissue repair.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
SARS-CoV-2 Infection in Children Lu, Xiaoxia; Zhang, Liqiong; Du, Hui ...
The New England journal of medicine,
04/2020, Volume:
382, Issue:
17
Journal Article
Peer reviewed
Open access
In this report, investigators in Wuhan, China, describe the spectrum of Covid-19 illness in children under the age of 16 years. Of 1391 children assessed and tested over a period of 4 weeks, 171 ...(12.3%) were confirmed to have SARS-CoV-2 infection.
Salen-Based Covalent Organic Framework Li, Li-Hua; Feng, Xiao-Lin; Cui, Xiao-Hui ...
Journal of the American Chemical Society,
05/2017, Volume:
139, Issue:
17
Journal Article
Peer reviewed
The Salen unit represents one of the most important ligands in coordination chemistry. We report herein the first example of a Salen-based covalent organic framework (COF), in which both the ...construction of the COF structure and the functionalization with Salen moieties have been realized in a single step. Due to its structural uniqueness, the obtained COF material, Salen-COF, possesses high crystallinity and excellent stability. Based on this, a series of metallo-Salen-based COFs were prepared via metalation for further applications.
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IJS, KILJ, NUK, PNG, UL, UM
Photocatalytic hydrogen (H2) production is significant to overcome challenges like fossil fuel depletion and carbon dioxide emission, but its efficiency is still far below that which is needed for ...commercialization. Herein, we achieve long‐term stable H2 bubbling production from water (H2O) and lactic acid via visible‐light‐driven photocatalysis in a porous microreactor (PP12); the catalytic system benefits from photocatalyst dispersion, charge separation, mass transfer, and dissociation of O−H bonds associated with H2O. With the widely used platinum/cadmium‐sulfide (Pt/CdS) photocatalyst, PP12 leads to a H2 bubbling production rate of 602.5 mmol h−1 m−2, which is 1000 times higher than that in a traditional reactor. Even when amplifying PP12 into a flat‐plate reactor with an area as large as 1 m2 and extending the reaction time to 100 h, the H2 bubbling production rate still remains at around 600.0 mmol h−1 m−2, offering great potential for commercialization.
Long‐term stable H2 production from H2O via visible‐light‐driven photocatalysis using lactic acid as a sacrificial reagent and Pt/CdS as a photocatalyst is achieved in a porous microreactor (PP12), with a H2 production rate as high as 602.5 mmol h−1 m−2. PP12 can be scaled up to a flat‐plate reactor with an area as large as 1 m2, without a decrease in H2 production efficiency, offering great potential for commercialization.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
Efficient electrocatalysts for oxygen evolution are vitally important for regenerative fuel cells and metal-air batteries. Herein, 3D mesoporous and ultrathin array of CoN nanosheets are synthesized ...on the Ni foam via thermal transformation of Co3O4 nanowire arrays. This array imparts enhanced active sites, mass diffusion, and electron transfer towards oxygen evolution reaction. The low overpotential of 323 mV at 30 mA cm−2, a Tafel slope of 74 mV dec−1, and a high potential conservation in a long process of electrolysis process are achieved. It is thus one robust and efficient electrocatalyst for OER.
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•Direct growth of mesoporous and ultrathin arrays of CoN nanosheets on Ni foam•Large specific surface areas of mesoporous and ultrathin array of CoN nanosheets•More available active sites of the CoN arrays for oxygen evolution reaction•Robust and efficient catalysts for oxygen evolution reaction, especially at high current densities
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Premise
A major goal of systematic biology is to uncover the evolutionary history of organisms and translate that knowledge into stable classification systems. Here, we integrate three sets of ...genome‐wide data to resolve phylogenetic relationships in Cornaceae (containing only Cornus s.l.), reconstruct the biogeographic history of the clade, and provide a revised classification using the PhyloCode to stabilize names for this taxonomically controversial group.
Methods
We conducted phylogenetic analyses using 312 single‐copy nuclear genes and 70 plastid genes from Angiosperms353 Hyb‐Seq, plus numerous loci from RAD‐Seq. We integrated fossils using morphological data and produced a dated phylogeny for biogeographical analysis.
Results
A well‐resolved, strongly supported, comprehensive phylogeny was obtained. Biogeographic analyses support an origin and rapid diversification of Cornus into four morphologically distinct major clades in the Northern Hemisphere (with an eastern Asian ancestor) during the late Cretaceous. Dispersal into Africa from eastern Asia likely occurred along the Tethys Seaway during the Paleogene, whereas dispersal into South America likely occurred during the Neogene. Diversification within the northern hemisphere likely involved repeated independent colonization of new areas during the Paleogene and Neogene along the Bering Land Bridge, the North Atlantic Land Bridge, and the Tethys Seaway. Thirteen strongly supported clades were named following rules of the PhyloCode.
Conclusions
Our study provides an example of integrating genomic and morphological data to produce a robust, explicit species phylogeny that includes fossil taxa, which we translate into an updated classification scheme using the PhyloCode to stabilize names.
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
Compared to the 3D lead-halide perovskites (MAPbX3, X=I/Cl), two dimensional (2D) perovskites have more flexible structures, with more relaxed limitations in the size of the organic cations and ...produce interesting variant of photophysical and electronic properties. Here, a universal deposition approach for stable and efficient MAPbX3 perovskite solar cells (PeSCs) displaying excellent reproducibility are presented via in-situ formed layered perovskites derived from polymeric ammonium anchor. The critical effect of in-situ formed layered perovskite (PEI)2PbI4 on the morphological and interfacial control of the above 3D perovskite are identified, and it is demonstrated that 2D perovskite films promote the formation of above perovskite films composed of micron-sized grains and provide better energy level alignment at the interface. Moreover, the incorporation of great moisture-resistant 2D materials, accompanying uniform and dense MAPbX3 films enhances long-term stability of the perovskite solar cells. As a result, a maximum PCE value of 13.8% for MAPbI3 solar cells on flexible substrate are achieved in ambient air. It is anticipated that our strategies to design and explore low dimensional perovskites can provide alternative route to address the critical concerns of stability and reproducibility in PeSCs.
In-situ-generated layered perovskite derived from polymeric ammonium were designed as a general fabrication method for controlling over the morphology to produce stable and reproducible perovskite solar cells with power conversion efficiency of 13.8% on flexible substrates in ambient air. Our design of novel two-dimensional materials affords a facile way with great tunability in perovskite families for photovoltaic applications.
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•In-situ-generated layered perovskite derived from polymeric ammonium were designed as a general fabrication method for controlling over the morphology to produce stable and reproducible perovskite solar cells with power conversion efficiency of 13.8% on flexible substrates in ambient air.•Our design of novel two-dimensional materials affords a facile way with great tunability in perovskite families for photovoltaic applications.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
The Changjiang estuary and the coastal area of the East China Sea (ECS) represent important interfaces of terrestrial and marine environments. This study included analyses of water and sediments ...collected during different seasons in these regions to determine the composition of microbial assemblages by means of 16S rRNA gene clone libraries. We retrieved 1946 sequences and 779 distinct operational taxonomic units from 36 clone libraries. Shannon-Weaver diversity index values and rarefaction analysis indicated that bacterial diversity in the sediment samples was much higher than in the water samples. Proteobacteria (72.9%) was the most abundant phylum, followed by Firmicutes (6.4%), Bacteroidetes (4.6%) and Actinobacteria (4.1%). In the water, clone sequences related to Alphaproteobacteria were the most abundant, whereas in the sediment samples, sequences affiliated with Gammaproteobacteria were predominant. Principal coordinate analysis showed that water samples collected from the Changjiang estuary and the ECS clustered separately. However, this spatial pattern could not be observed in sediment samples, which were mainly distinguished from one another by the season. Bacterial diversity in the Changjiang estuary was higher than that in the ECS, which may be the result of the mixing of bacterial communities from the Changjiang River, the estuary and the coastal ocean.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
Recent studies have found that known functions of circular RNAs (circRNAs) include sequestration of microRNAs (miRNAs) or proteins, modulation of transcription and interference with splicing, and ...even translation to produce polypeptides. The zebrafish model is also demonstrably similar to humans in many studies. To explore the changes in circRNAs during embryonic development and to further research the mechanism of action of circRNAs in development‐related diseases, Zebrafish embryos at the blastula period, gastrula period, segmentation period, throat stage, and incubation period were collected. Illumina deep‐sequencing technology and CircRNA Identifier (CIRI) algorithm were used to detect circRNAs. In total, we identified 1,028 circRNAs (junction reads ≥5 and p < 0.05). Considering that the function of circRNAs is related to host genes, a bioinformatics analysis revealed these differentially expressed host genes are involved in NOTCH signaling pathways, cardiovascular system development, retinal ganglion cell axon guidance, and so on. Moreover, circRNAs can participate in biological regulation through the function of miRNA sponges. TargetScan and miRanda were used to predict 73 miRNAs binding to circRNAs such as miR‐19b, miR‐124, and so on. Some miRNAs play important roles in embryogenesis. The peak expression of circRNAs is distributed at different time points, suggesting that it may be involved in embryogenesis at different stages. Our study provides a foundation for understanding the dynamic regulation of circRNA transcriptomes during embryogenesis and identifies novel key circRNAs that might control embryonic development in a zebrafish model.
Recent studies have found that known functions of circRNAs include sequestration of miRNAs or proteins, modulation of transcription and interference with splicing, and even translation to produce polypeptides. The zebrafish model is also demonstrably similar to humans in many studies. To explore the changes in circRNAs during embryonic development, further to research the mechanism of action of circRNAs in development‐related diseases, Zebrafish embryos at the blastula period, gastrula period, segmentation period, throat stage, and incubation period were collected. Illumina deep‐sequencing technology and CIRI algorithm were used to detect circRNAs. In total, we identified 1,028 RNAs (junction reads ≥ 5 and p < 0.05). Considering that the function of circRNA is related to host genes, bioinformatics analysis revealed thaht these differentially expressed host genes are involved in NOTCH signaling pathways, cardiovascular system development, retinal ganglion cell axon guidance, and so on. Moreover, circRNAs can participate in biological regulation through miRNA sponge function. TargetScan and miRanda were used to predict 73 miRNAs binding to circRNAs such as miR‐19b, miR‐124, and so on. Some miRNAs play important roles in embryogenesis. The peak expression of circRNAs is distributed at different time points, suggesting that it may be involved in embryogenesis at different stages. Our study provides a foundation for understanding the dynamic regulation of circRNA transcriptomes during embryogenesis and identifies novel key circRNAs that might control embryonic development in a zebrafish model.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
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