A spacer design strategy for CRISPR-Cas12f1 with single-nucleotide polymorphism mutation resolution capability and its application in the mutations diagnosis of pathogens.

Infectious diseases remain a major global issue in public health. It is important to develop rapid, sensitive, and accurate diagnostic methods to detect pathogens and their mutations. Cas12f1 is an exceptionally compact RNA-guided nuclease and have the potential to fulfill the clinical needs. Based on the interaction between crRNA-SSDNA binary sequence and Cas12f1, here, we addressed the essential features that determine the recognition ability of CRISPR-Cas12f1 single-nucleotide polymorphism (SNP), such as the length of spacer region and the base pairing region that determines the trans-cleavage of ssDNA. A fine-tuning spacer design strategy is also proposed to enhance the SNP recognition capability of CRISPR-Cas12f1. The optimized spacer confers the Cas12f1 system a strong SNP identification capability for viral or bacterial drug-resistance mutations, with a specificity ratio ranging from 19.63 to 110.20 and an admirable sensitivity up to 100  copy/µL. Together, the spacer screening and CRISPR-Cas12f1 based SNP identification method, is sensitive and versatile, and will have a wide application prospect in pathogen DNA mutation diagnosis and other mutation profiling.

Vps33B in Dendritic Cells Regulates House Dust Mite-Induced Allergic Lung Inflammation.

Dendritic cells (DCs) are the most specialized APCs that play a critical role in driving Th2 differentiation, but the mechanism is not fully understood. Here we show that vacuolar protein sorting 33B (Vps33B) plays an important role in this process. Mice with Vps33b-specific deletion in DCs, but not in macrophages or T cells, were more susceptible to Th2-mediated allergic lung inflammation than wild-type mice. Deletion of Vps33B in DCs led to enhanced CD4+ T cell proliferation and Th2 differentiation. Moreover, Vps33B specifically restrained reactive oxygen species production in conventional DC1s to inhibit Th2 responses in vitro, whereas Vps33B in monocyte-derived DCs and conventional DC2s was dispensable for Th2 development in asthma pathogenesis. Taken together, our results identify Vps33B as an important molecule that mediates the cross-talk between DCs and CD4+ T cells to further regulate allergic asthma pathogenesis.

Correlation between dietary theobromine intake and low cognitive performance in older adults in the United States: A cross-sectional study based on the National Health and Nutrition Examination Survey.

BACKGROUND AND OBJECTIVES: Few studies have investigated the effects of dietary theobromine intake on the cognitive performance of older adults. Therefore, we investigated these effects in older adults in the United States. METHODS AND STUDY DESIGN: In this cross-sectional study, we used data (2011-2014) from the National Health and Nutrition Examination Survey. Intake of theobromine intake was obtained through two 24-h dietary recall interviews and was adjusted by energy. Cognitive performance was assessed using the animal fluency test, Consortium to Establish a Registry for Alzheimer's Disease Word Learning subtest (CERAD), and Digit Symbol Substitution Test (DSST). Logistic regression and restricted cubic spline models were constructed to evaluate the correlation between the dietary intake of theobromine from different sources and the likelihood of low cognitive performance. RESULTS: The fully adjusted model revealed that compared with the lowest quintile, the odds ratios (with 95% confidence intervals) of cognitive performance in the CERAD test were 0.42 (0.28-0.64), 0.34 (0.14-0.83), 0.25 (0.07-0.87), and 0.35 (0.13-0.95) for the highest quintile of total theobromine intake and that from chocolate, coffee, and cream, respectively. Dose-response relationship analysis indicated nonlinear correlations between the likelihood of low cognitive performance and die-tary theobromine (total intake and that from chocolate, coffee, and cream). An L-shaped relationship was ob-served between total theobromine intake and cognitive performance in the CERAD test. CONCLUSIONS: The dietary intakes of theobromine (total and that from chocolate, coffee, and cream) may protect older adults, particularly men, against low cognitive performance.

Atomically Dispersed Iron Regulating Electronic Structure of Iron Atom Clusters for Electrocatalytic H2 O2 Production and Biomass Upgrading.

The integration of highly active single atoms (SAs) and atom clusters (ACs) into an electrocatalyst is critically important for high-efficiency two-electron oxygen reduction reaction (2e- ORR) to hydrogen peroxide (H2 O2 ). Here we report a tandem impregnation-pyrolysis-etching strategy to fabricate the oxygen-coordinated Fe SAs and ACs anchored on bacterial cellulose-derived carbon (BCC) (FeSAs/ACs-BCC). As the electrocatalyst, FeSAs/ACs-BCC exhibits superior electrocatalytic activity and selectivity toward 2e- ORR, affording an onset potential of 0.78 V (vs. RHE) and a high H2 O2 selectivity of 96.5 % in 0.1 M KOH. In a flow cell reactor, the FeSAs/ACs-BCC also achieves high-efficiency H2 O2 production with a yield rate of 12.51±0.18 mol gcat -1 h-1 and a faradaic efficiency of 89.4 %±1.3 % at 150 mA cm-2 . Additionally, the feasibility of coupling the produced H2 O2 and electro-Fenton process for the valorization of ethylene glycol was explored in detail. The theoretical calculations uncover that the oxygen-coordinated Fe SAs effectively regulate the electronic structure of Fe ACs which are the 2e- ORR active sites, resulting in the optimal binding strength of *OOH intermediate for high-efficiency H2 O2 production.

Serum and glucocorticoid-regulated kinase 1 regulates transforming growth factor ß1-connective tissue growth factor pathway in chronic rhinosinusitis.

PURPOSE: Serum/glucocorticoid-regulated kinase 1 (SGK1) has been identified as a crucial regulator in fibrotic disorders. Herein, we explored SGK1 role in tissue remodeling of chronic rhinosinusitis (CRS). METHODS: Lentivirus was employed to generate an SGK1-overexpressing human bronchial epithelial cell (16HBE) line. To screen SGK1 downstream genes, RNA sequencing was performed on SGK1-overexpressing and control cell lines. To determine protein and gene expression levels, immunohistochemistry, western blotting, and quantitative real-time polymerase chain reaction were employed. Correlation analysis was performed using mRNA expression levels of SGK1, transforming growth factor ß1 (TGF-ß1), and connective tissue growth factor (CTGF) derived from CRS mucosal tissue and GEO database. Gene set enrichment analysis was conducted using gene sets from Molecular Signatures Database. The severity of symptoms in CRS patients was assessed using the 22-Item Sinonasal Outcome Test. RESULTS: SGK1 overexpression significantly increased the expression of connective tissue growth factor (CTGF) in 16HBE cells (P < 0.01). Consistently, CTGF protein level was considerably greater in mucosal tissue of CRS without nasal polyps (CRSsNP) than in CRS with nasal polyps (CRSwNP) (P < 0.05) or in control subjects (P < 0.01). TGF-ß1 protein level was higher in mucosal tissue of CRSsNP patients than in CRSwNP patients (P < 0.001) or in the control group (P < 0.01). mRNA levels of SGK1 and CTGF (P < 0.05, r = 0.668; P = 0.001, r = 0.630), TGF-ß1 and CTGF (P < 0.05, r = 0.560; P < 0.05, r = 0.420), as well as SGK1 and TGF-ß1(P < 0.05, r = 0.612; P < 0.05, r = 0.524) were significantly correlated in CRS mucosal tissue and GSE36830 dataset, respectively. TGF-ß1-induced upregulated genes were significantly enriched in SGK1 overexpression group. In vitro assays, TGF-ß1 promoted SGK1 and CTGF expression in a concentration- and time-dependent manner. Administrating an SGK1 inhibitor, GSK650394, significantly inhibited TGF-ß1-induced CTGF expression in 16HBE and dispersed primary nasal polyp cells. CONCLUSIONS: TGF-ß1 stimulation significantly increases SGK1 and CTGF expression. By regulating TGF-ß1-CTGF pathway, SGK1 may participate in tissue remodeling in the pathological mechanism of CRS.

Considerations regarding centromere assembly in plant whole-genome sequencing.

The assembly of centromeric regions has become one of the most intractable tasks in whole-genome sequencing due to the enrichment of highly repetitive DNA sequences in most eukaryotic centromeres. Here, we describe a method used to identify centromeric DNAs through chromatin immunoprecipitation and sequencing (ChIP-seq). By mapping ChIP-seq reads, centromeric regions can be indicated in genome assemblies. We demonstrated that the assembly quality of centromeres obtained using ChIP-seq mapping can reflect and indicate the quality of a whole-genome assembly. We discuss an expected 'high-quality' centromere assembly obtained via centromere ChIP-seq mapping.

A coordination environment effect of single-atom catalysts on their nitrogen reduction reaction performance.

Understanding the structure-activity relationship of an active site is of great significance toward the rational design of highly active catalysts. In this study, we have performed density functional theory calculations to investigate the coordination environment effect of Fe-, N-, and O-doped carbon on their nitrogen reduction reaction (NRR) properties. Our results indicate that the presence of O atoms in the coordination environment favors the activation of N2 molecules but is unfavorable to the stability, while the existence of N will weaken the adsorption of N2 and increase the reaction barrier of the first hydrogenation step. Fe-C4-C has the lowest potential for activating N2. A compromise is Fe-NxC4-x-C, where the interaction of C and N in coordination regulates the spin polarization of Fe and thus the 3d states around the Fermi level. Fe-N2C2-C was found to be the best one and NRR can proceed via the distal and alternative reaction pathways with the first hydrogenation step of N2 being the potential-limiting step and the Gibbs free energy change (ΔG) being 0.75 eV.

MiR-224-5p Targeting OCLN Promotes the Proliferation, Migration, and Invasion of Clear Cell Renal Cell Carcinoma Cells.

A number of studies reported that miR-224-5p is involved in a variety of cancer-related cellular processes, yet its physiological role in clear cell renal cell carcinoma (ccRCC) remains unclear. In order to clarify the function of miR-224-5p in ccRCC, real-time quantitative-PCR was conducted to compare the expression of miR-224-5p in human normal renal tubular epithelial cell lines and ccRCC cell lines first, and a strikingly upregulated expression was observed in ccRCC cell lines. Inhibition of miR-224-5p expression by microRNA inhibitors could inhibit the proliferation, migration, and invasion of ccRCC cells. Besides, it was validated by dual-luciferase assay in which miR-224-5p directly targeted OCLN gene. The expression of OCLN was downregulated in ccRCC cells, and overexpression of miR-224-5p could inhibit the mRNA and protein expression levels of OCLN. Overexpression of OCLN could reduce the proliferation, migration, and invasion of ccRCC cells, while overexpressed miR-224-5p could partially reverse that inhibitory effect. Therefore, the promotive effect of miR-224-5p on the proliferation, invasion, and migration of ccRCC cell lines was at least partly due to the inhibition of OCLN expression. These findings highlighted the important function of miR-224-5p, which was promoting cell proliferation, migration, and invasion by downregulating OCLN, in the pathogenesis of ccRCC, and provided a potential treatment strategy.

Endoplasmic reticulum stress exacerbates inflammation in chronic rhinosinusitis with nasal polyps via the transcription factor XBP1.

Endoplasmic reticulum (ER) stress results in the activation of the unfolded protein response (UPR), a process that is involved in the pathogenesis of many inflammatory diseases. However, the role of ER stress in chronic rhinosinusitis with nasal polyps (CRSwNP) has yet to be elucidated. In this study, we found that the protein expression levels of a range of ER stress regulators, including p-PERK, ATF4, ATF6 and XBP1s, were significantly increased in CRSwNP compared to controls. Importantly, the expression of ATF4 and XBP1s was positively correlated with heightened inflammation in CRSwNP. In human nasal epithelial cells, the ER stress inducer tunicamycin (TM) could potentiate Toll-like receptors (TLRs) induced proinflammatory cytokines production. Furthermore, we found that the silencing of XBP1, but not ATF4 or ATF6, abrogated the proinflammatory effect of TM. Mechanistically, ER stress did not affect the NF-κB, MAPK or IRF3 signaling pathways. However, the ER stress regulator XBP1s was able to bind directly to the promoter region of inflammatory genes to modulate gene transcription. Besides, the commensal bacteria Staphylococcus aureus and several inflammatory factors, such as IL4, IL13, IL17 and IFNγ, could induce ER stress in epithelial cells. Collectively, ER stress plays a crucial role in facilitating TLR-induced inflammation. Targeting XBP1 can inhibit the inflammatory response, thus offering a potential approach to treat CRSwNP.

CRISPR-based RNA-binding protein mapping in live cells.

RNA-binding proteins (RBPs) are involved in all aspects of RNA metabolism, and RNA-RBP interactions are important for cell homeostasis and viral replication. The global RNA-binding proteome was recently reported; however, little is known about the proteins that bind to specific RNAs. In this study, we describe a novel CRISPR-based RNA interaction proteomics method in live cells. In brief, dCas13a with an HA tag was expressed in cells and bound to an RNA of interest with the help of gRNA. The RNA-protein complexes physically bound to dCas13a-HA were crosslinked using UV light and captured using anti-HA beads, after which the proteins were purified and identified using mass spectrometry. We optimized this system and subsequently applied it to U1 small nuclear RNA, which revealed 226 proteins.

miR-129-5p inhibits clear cell renal cell carcinoma cell proliferation, migration and invasion by targeting SPN.

OBJECTIVE: Our study aims to investigate the mechanism of the miR-129-5p/SPN axis in clear cell renal cell carcinoma (ccRCC), providing a novel direction for the targeted therapy of ccRCC. METHODS: Bioinformatics methods were implemented to find the differentially expressed genes (DEGs) associated with ccRCC from TCGA database. qRT-PCR was performed to detect miR-129-5p and SPN mRNA expression, while western bot was carried out for the detection of protein expression of SPN. Bioinformatics analysis was used to predict the binding sites of miR-129-5p on SPN 3'UTR, while dual-luciferase assay was conducted to verify their binding relationship. CCK-8 assay, colony formation assay, wound healing assay and Transwell assay were employed to measure ccRCC cell proliferative ability, cell formation ability, cell migratory and invasive abilities. Flow cytometry was implemented to assess cell cycle and apoptosis. RESULTS: miR-129-5p exhibited a significantly down-regulated expression level in ccRCC, while SPN showed a remarkably up-regulated expression level. Overexpressed miR-129-5p inhibited ccRCC cell proliferative, invasive and migratory capacities while induced cell cycle arrest in G0/G1 phase and promoted cell apoptosis. Dual-luciferase assay confirmed that there was a binding relationship between miR-129-5p and SPN. Moreover, overexpressed miR-129-5p remarkably reduced SPN expression in cancer cells, weakened the promoting effect of SPN on cell proliferation, migration, invasion and cell cycle progress, and led to enhanced cell apoptotic activity. CONCLUSIONS: Our study proves the regulatory effect of the miR-129-5p/SPN axis in ccRCC, and provides a novel potential target for precise treatment of patients with ccRCC.

Screening Novel Drug Candidates for Kidney Renal Clear Cell Carcinoma Treatment: A Study on Differentially Expressed Genes through the Connectivity Map Database.

OBJECTIVE: Kidney renal clear cell carcinoma (KIRC) is a common cancer with high morbidity and mortality in renal cancer. Thus, the transcriptome data of KIRC patients in The Cancer Genome Atlas (TCGA) database were analyzed and drug candidates for the treatment of KIRC were explored through the connectivity map (CMap) database. METHODS: The transcriptome data of KIRC patients were downloaded from TCGA database, and KIRC-associated hub genes were screened out through differential analysis and protein-protein interaction (PPI) network analysis. Afterward, the CMap database was used to select drug candidates for KIRC treatment, and the drug-targeted genes were obtained through the STITCH database. A PPI network was constructed by combining drug-targeted genes with hub genes that affected the pathogenesis of KIRC to obtain final hub genes. Finally, combining hub genes and KIRC-associated hub genes, the pathways affected by drugs were explored by pathway enrichment analysis. RESULTS: A total of 2,312 differentially expressed genes were found in patients, which were concentrated in immune cell activity, cytokine, and chemokine secretion pathways. Drug screening disclosed 5 drug candidates for KIRC treatment: fedratinib, Ly344864, geldanamycin, AS-605240, and luminespib. Based on drug-targeted genes and KIRC-associated hub genes, 16 hub genes were screened out. Pathway enrichment analysis revealed that drugs mainly affected pathways such as neuroactive ligand pathways, cell adhesion, and chemokines. CONCLUSION: The above results indicated that fedratinib, LY 344864, geldanamycin, AS-605240, and luminespib could be used as candidates for KIRC therapy. The findings from this study will make contributions to the treatment of KIRC in the future.

Effects of organic chromium sources on growth performance, lipid metabolism, antioxidant status, breast amino acid and fatty acid profiles in broilers.

BACKGROUND: Trivalent chromium (Cr) is involved in carbohydrate, lipid, protein and nucleic acid metabolism in animals. This study evaluated the effects of different organic Cr forms with Cr methionine (CrMet), Cr picolinate (CrPic), Cr nicotinate (CrNic), and Cr yeast (Cr-yeast) at the level of 400 µg kg-1 Cr, on growth performance, lipid metabolism, antioxidant status, breast amino acid and fatty acid profiles of broilers. In total, 540 one-day-old Arbor Acres male broilers were randomly assigned to five treatments with six replicates (18 broilers per replicate) until day 42. RESULTS: The results showed growth performance was not affected by Cr sources. The Cr-yeast group had lower serum cortisol levels than the CrNic group (P < 0.05). Besides, Cr-yeast increased methionine and cysteine content in breast compared with the control group. Liver malondialdehyde content was lower in the CrMet group than the CrPic group on day 42 (P < 0.05). The n-3 polyunsaturated fatty acid (PUFA) values were increased, but the n-6/n-3 PUFA ratio was decreased in both CrMet and CrNic groups (P < 0.05). There were no significant effects on broilers' serum antioxidant status and breast total essential amino acid content among all treatments. CONCLUSIONS: Diets supplemented with organic Cr could regulate lipid metabolism, and improve amino acid and fatty acid profiles in broiler breast. Moreover, Cr-yeast was the most effective source in improving methionine and cysteine content, whereas CrMet was more effective than CrNic in increasing n-3 PUFA value and decreasing n-6/n-3 PUFA ratio in breast meat and effectively strengthened liver antioxidant ability than CrPic. © 2020 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Fe-Co Alloyed Nanoparticles Catalyzing Efficient Hydrogenation of Cinnamaldehyde to Cinnamyl Alcohol in Water.

Selective hydrogenation of C=O against the conjugated C=C in cinnamaldehyde (CAL) is indispensable to produce cinnamyl alcohol (COL). Nonetheless, it is challenged by the low selectivity and the need to use organic solvents. Herein, for the first time, we report the use of Fe-Co alloy nanoparticles (NPs) on N-doped carbon support as a selective hydrogenation catalyst to efficiently convert CAL to COL. The resultant catalyst with the optimized Fe/Co ratio of 0.5 can achieve an exceptional COL selectivity of 91.7 % at a CAL conversion of 95.1 % in pure water medium under mild reaction conditions, ranking it the best performed catalyst reported to date. The experimental results confirm that the COL selectivity and CAL conversion efficiency are, respectively promoted by the presence of Fe and Co, while the synergism of the alloyed Fe-Co is the key to concurrently achieve high COL selectivity and CAL conversion efficiency.

Electrocatalytically Active Fe-(O-C2 )4 Single-Atom Sites for Efficient Reduction of Nitrogen to Ammonia.

Single-atom catalysts have demonstrated their superiority over other types of catalysts for various reactions. However, the reported nitrogen reduction reaction single-atom electrocatalysts for the nitrogen reduction reaction exclusively utilize metal-nitrogen or metal-carbon coordination configurations as catalytic active sites. Here, we report a Fe single-atom electrocatalyst supported on low-cost, nitrogen-free lignocellulose-derived carbon. The extended X-ray absorption fine structure spectra confirm that Fe atoms are anchored to the support via the Fe-(O-C2 )4 coordination configuration. Density functional theory calculations identify Fe-(O-C2 )4 as the active site for the nitrogen reduction reaction. An electrode consisting of the electrocatalyst loaded on carbon cloth can afford a NH3 yield rate and faradaic efficiency of 32.1 µg h-1 mgcat. -1 (5350 µg h-1 mgFe -1 ) and 29.3 %, respectively. An exceptional NH3 yield rate of 307.7 µg h-1 mgcat. -1 (51 283 µg h-1 mgFe -1 ) with a near record faradaic efficiency of 51.0 % can be achieved with the electrocatalyst immobilized on a glassy carbon electrode.

Ambient Electrosynthesis of Ammonia on a Core-Shell-Structured Au@CeO2 Catalyst: Contribution of Oxygen Vacancies in CeO2.

Electrosynthesis of NH3 through the N2 reduction reaction (NRR) under ambient conditions is regarded as promising technology to replace the industrial energy- and capital-intensive Haber-Bosch process. Herein, a room-temperature spontaneous redox approach to fabricate a core-shell-structured Au@CeO2 composite, with Au nanoparticle sizes below about 10 nm and a loading amount of 3.6 wt %, is reported for the NRR. The results demonstrate that as-synthesized Au@CeO2 possesses a surface area of 40.7 m2 g-1 and a porous structure. As an electrocatalyst, it exhibits high NRR activity, with an NH3 yield rate of 28.2 µg h-1 cm-2 (10.6 µg h-1 mg-1 cat. , 293.8 µg h-1 mg-1 Au ) and a faradaic efficiency of 9.50 % at -0.4 V versus a reversible hydrogen electrode in 0.01 m H2 SO4 electrolyte. The characterization results reveal the presence of rich oxygen vacancies in the CeO2 nanoparticle shell of Au@CeO2 ; these are favorable for N2 adsorption and activation for the NRR. This has been further verified by theoretical calculations. The abundant oxygen vacancies in the CeO2 nanoparticle shell, combined with the Au nanoparticle core of Au@CeO2 , are electrocatalytically active sites for the NRR, and thus, synergistically enhance the conversion of N2 into NH3 .

Theoretical study of single transition metal atom modified MoP as a nitrogen reduction electrocatalyst.

It is highly attractive but challenging to develop earth-abundant electrocatalysts for nitrogen (N2) fixation. Here, by using density functional theory (DFT), we systematically investigate various single transition metal atom (Ti, V, Cr, Mn, Fe, Co, Ni, Ru, Rh and Pd) modified MoP surfaces as potential N2 reduction electrocatalysts for ammonia (NH3) synthesis. Through comparison of the stabilities of metal atom modified MoP, the adsorption energies and the bond lengths of N2 on different atom modified MoP, we select Mn and V as two candidates and study in detail the possible N2 reduction reaction (NRR) pathways for Mn-MoP and V-MoP. Our results revealed that Mn-MoP and V-MoP exhibit energy change values of 0.95 eV and 0.65 eV, respectively, with the first hydrogenation step being the potential-limiting step. Mn-MoP can efficiently suppress *H adsorption and reduce the competition of the hygrogen evolution reaction (HER) with the NRR; whereas, V-MoP cannot. Therefore, Mn-MoP is a better catalyst to realize the nitrogen reduction reaction. Overall, this work takes one step toward the NRR possibility of transition metal phosphides and provides some important insights and guidance to experiments.

Effects of a Lysine-Involved Maillard Reaction on the Structure and In Vitro Activities of Polysaccharides from Longan Pulp.

The effects of amino acid-involved Maillard reactions (MRs) on the structure and activities of longan pulp polysaccharides (LPs), which were heteropolysaccharides mainly composed of glucose, galactose, mannose, rhamnose, glucuronic acid, ribose, and galacturonic acid, were investigated. The changes of browning degree and molecular weight (Mw) distribution in the MR systems containing LPs and amino acids (lysine, proline, or glycine) indicated that lysine was more active in conjugating with LPs. The MR-modified LPs (MLPs) obtained via a 4 h MR between LPs and lysine showed obvious structural differences from LPs. Specifically, particle-like LPs contained 94% fractions with a Mw less than 7.07 kDa, by contrast, network-like MLPs contained 45% fractions with a Mw larger than 264.1 kDa. Moreover, MLPs showed stronger radical scavenging abilities and macrophage immunostimulating effects, but weaker cancer cell growth-inhibitory abilities. The results indicate that the amino acid-involved MR is a promising method to modify native polysaccharides for better biological properties.

Highly Dispersed Copper Nanoparticles Supported on Activated Carbon as an Efficient Catalyst for Selective Reduction of Vanillin.

Highly dispersed copper nanoparticles (Cu NPs) supported on activated carbon (AC) are effectively synthesized by one-pot carbothermal method at temperature range of 400-700 °C. The X-ray diffraction, transmission electron microscopy, X-ray photoelectron spectroscopy, and Brunauer-Emmett-Teller analysis reveal that Cu NPs with diameters of 20-30 nm are evenly anchored in carbon matrix. The 15 wt%-Cu/AC-600 catalyst (derived at 600 °C) exhibits best bifunctional catalysis of aqueous-phase hydrodeoxygenation (HDO) and organic-phase transfer-hydrogenation reaction (THR) to selectively transform vanillin to 2-methoxy-4-methylphenol (MMP). In HDO of vanillin, the as-prepared catalyst achieves a 99.9% vanillin conversion and 93.2% MMP selectivity under 120 °C, 2.0 MPa H2 within 5 h. Meanwhile, near-quantitative vanillin conversion and 99.1% MMP selectivity are also obtained under 180 °C within 5 h in THR of vanillin by using 2-propanol as hydrogen donor. The transforming pathways of vanillin are also proposed: vanillin is transformed into MMP via intermediate of 4-hydroxymethyl-2-methoxyphenol in HDO case and by direct hydrogenolysis of vanillin in THR course. More importantly, the activity and the selectivity do not change after 5 cycles, indicating the catalyst has excellent stability. The Cu-based catalyst is relatively cheap and preparation method is facile, green, and easy scale-up, thus achieving a low-cost transformation of biomass to bio-oils and chemicals.

An investigation of Na-related defects in Cu2ZnSnSe4.

Using hybrid density functional theory, here, we have investigated the electronic, defect and migration properties of Na-related defects in the earth-abundant solar cell absorber material Cu2ZnSnSe4 (CZTSe). We find that among all the Na-related defects, NaZn acts the same way as VCu and CuZn; it is an acceptor and contributes to the p-type conductivity. NaSn is a deep level defect, but it is energetically unfavorable and can be suppressed by the growth conditions. Besides, through migration energy analysis, we prove that Na can easily move in CZTSe through interstitial Na and Cu vacancy mediated mechanisms.