Rapid Fabrication of N-, Cu-, and Co-Doped Electrodes with Strong Electronic Coupling by Cold Plasma for Electrocatalytic Reduction of Nitrate to Ammonia.

Electrochemical NOx- reduction (NOxRR) is a sustainable technology for ammonia synthesis. The development of a simple, fast, and economical catalytic electrode preparation technique is crucial for large-scale ammonia synthesis. Herein, we propose a plate-to-plate DBD plasma strategy to synthesize the catalytic electrodes M-N/CP (M = Cu, Co, Ni, CuCo, and CuNi), achieving in suit codoping of N and bimetals on carbon paper (CP) at room temperature within 3 h. N-doping improves the metal loading and the NOxRR performance by forming N-M bonds. The electronic coupling and synergistic effect of Cu and Co sites facilitate the relay conversion of NO3- to NO2- to NH3. Notably, the NO3- removal efficiency of CuCo-N/CP reaches 82%, with NH3 yield rate of 346 µg h-1 cm-2, and the faradaic efficiency is as high as 86% at -0.58 V vs RHE, which remains competitive in terms of NOxRR performance. Importantly, wet flue gas denitrification and desulfurization coupled with electrocatalytic reduction can convert NOx and SO2 to (NH4)2SO4, Additionally, the maneuverability of plasma technology offers the potential for batch preparation of CuCo-N/CP electrodes for electrochemically driven wet denitrification wastewater valorization.

Pleural parasite infection presenting with an isolated pleural effusion misdiagnosed as tuberculosis: a case report.

Pleural parasitic infection is an extremely rare disease of the pleura caused by a variety of parasites, with paragonimiasis infection being the most common. The lack of specific clinical symptoms for paragonimiasis makes it easy to misdiagnose as tuberculosis, causing unnecessary drug-related adverse effects and financial burdens from incorrect treatment. We report a case of a pediatric patient presenting with an isolated pleural effusion that was misdiagnosed as tuberculosis; the patient was eventually diagnosed with pleuropulmonary paragonimiasis infection after immunologic and serologic tests. The patient finally recovered after anti-parasitic treatment involving praziquantel administration. This report will help increase awareness of this disease among medical practitioners to avoid misdiagnosis and treatment delays which may lead to disease progression.

[Correlation of lipid metabolism-related single nucleotide polymorphisms with abnormal semen quality in men].

OBJECTIVE: To explore the potential impact of lipid metabolism-related single nucleotide polymorphisms (SNP) on semen quality in men. METHODS: We selected 284 semen samples from Xingtai Infertility Hospital and Hebei Human Sperm Bank collected between February and October 2023, 33 from oligozoospermia (OS), 97 from asthenozoospermia (AS) and 54 from oligoasthenozoospermia (OAS) patients and the other 100 from normal men. We performed computer-assisted semen analysis (CASA) of the samples, extracted blood DNA and, using the MassARRAY System, genotyped the target genes, determined the genotypes of 13 SNPs and compared their distribution, their correlation with BMI and semen quality in different groups. RESULTS: The mutant homozygous (TT) genotype of the FADS2 rs2727270 gene seemed to be a risk factor for AS (OR = 4.420, P= 0.047), while the APOA2 rs5082-A allele and MC4R rs17782313 heterozygous (TC) genotype important protective factors for OS (OR = 0.422 and 0.389; P= 0.045 and 0.043, respectively). A significantly higher sperm concentration was found associated with the MC4R rs17782313 heterozygous (TC) genotype than with the homozygous (CC) genotype. Stratification analysis showed that the protective effect of the TC genotype was decreased with increased BMI and remained with the interaction of the rs5082 and rs17782313 genotypes. CONCLUSION: FADS2 rs2727270, APOA2 rs5082 and MC4R rs17782313 were significantly correlated with the risk of abnormal semen parameters.

A case report on atypical presentations of Dyke-Davidoff-Masson syndrome.

Dyke-Davidoff-Masson Syndrome (DDMS) is a rare neurological disease with an unknown incidence. The manifestations of DDMS are variable, while typical symptoms are seizures, hemiparesis, and mental retardation. Here, we present a case involving a 19-year-old male patient who presents with headaches, mood changes, and a history of seizures during childhood. Based on the neuroimages, a diagnosis of DDMS was established. The application of sertraline hydrochloride as a therapeutic intervention has alleviated the symptoms. This case report illustrates the importance of understanding the clinical features of DDMS based on imaging.

[Expressions of zinc homeostasis proteins, GPR39 and ANO1 mRNA in the sperm of asthenozoospermia patients and their clinical significance].

OBJECTIVE: To explore the expressions of zinc homeostasis-related proteins, G protein-coupled receptor 39 (GPR39) and ANO1 mRNA in the sperm of patients with asthenozoospermia (AS), and analyze their correlation with sperm motility. METHODS: We collected semen samples from 82 male subjects with PR+NP < 40%, PR < 32% and sperm concentration > 15×106/ml (the AS group, n = 40) or PR+NP ≥ 40%, PR ≥ 32% and sperm concentration > 15×106/ml (the normal control group, n = 42). We analyzed the routine semen parameters and measured the zinc content in the seminal plasma using the computer-assisted sperm analysis system, detected the expressions of zinc transporters (ZIP13, ZIP8 and ZNT10), metallothioneins (MT1G, MT1 and MTF), GPR39, and calcium-dependent chloride channel protein (ANO1) in the sperm by real-time quantitative PCR (RT qPCR), examined free zinc distribution in the sperm by laser confocal microscopy, and determined the expressions of GPR39 and MT1 proteins in the sperm by immunofluorescence staining, followed by Spearman rank correlation analysis of their correlation with semen parameters. RESULTS: There was no statistically significant difference in the zinc concentration in the seminal plasma between the AS and normal control groups (P>0.05). Compared with the controls, the AS patients showed a significantly reduced free zinc level (P<0.05), relative expressions of MT1G, MTF, ZIP13, GPR39 and ANO1 mRNA (P<0.05), and that of the GPR39 protein in the AS group (P<0.05). No statistically significant differences were observed in the relative expression levels of ZIP8, ZNT10 and MT1 mRNA between the two groups (P>0.05). The relative expression levels of GPR39, ANO1, MT1G and MTF mRNA were positively correlated with sperm motility and the percentage of progressively motile sperm (P<0.05). CONCLUSION: The expressions of zinc homeostasis proteins (MT1G, MTF and ZIP13), GPR39 and ANO1 mRNA are downregulated in the sperm of asthenozoospermia patients, and positively correlated with sperm motility.

Advancements in Single-Cell RNA Sequencing Research for Neurological Diseases.

Neurological diseases are a major cause of the global burden of disease. Although the mechanisms of the occurrence and development of neurological diseases are not fully clear, most of them are associated with cells mediating neuroinflammation. Yet medications and other therapeutic options to improve treatment are still very limited. Single-cell RNA sequencing (scRNA-seq), as a delightfully potent breakthrough technology, not only identifies various cell types and response states but also uncovers cell-specific gene expression changes, gene regulatory networks, intercellular communication, and cellular movement trajectories, among others, in different cell types. In this review, we describe the technology of scRNA-seq in detail and discuss and summarize the application of scRNA-seq in exploring neurological diseases, elaborating the corresponding specific mechanisms of the diseases as well as providing a reliable basis for new therapeutic approaches. Finally, we affirm that scRNA-seq promotes the development of the neuroscience field and enables us to have a deeper cellular understanding of neurological diseases in the future, which provides strong support for the treatment of neurological diseases and the improvement of patients' prognosis.

Clinical Value of Human Endogenous Retrovirus-H Long Terminal Repeat Associating 2 (HHLA2) in Small Cell Lung Cancer.

Objective: Human endogenous retrovirus-H long terminal repeat associating 2 (HHLA2) is a new immune checkpoint in the B7 family, and the value of HHLA2 in small cell lung cancer (SCLC) is unknown. Methods: We retrospectively detected HHLA2 expression by immunohistochemistry in SCLC patients. Moreover, plasma biomarkers of SCLC were detected retrospectively. Results: Seventy-four percent of SCLC patients exhibited HHLA2 expression. HHLA2 staining was localised within the nucleus of SCLC cells, while no staining was detected in normal lung tissue specimens. The correlation between HHLA2 expression and clinical factors was also analysed. Limited stage (LS) SCLC was more common than extensive stage (ES) SCLC among patients with HHLA2 staining. SCLC patients without metastasis had higher HHLA2 expression than SCLC patients with metastasis. HHLA2 expression was more frequently detected in the group with a tumour size greater than 5 cm than in the group with a tumour size less than 5 cm. The proportion of patients with HHLA2-positive staining was greater in the stage III and IV SCLC groups than in the stage I and II SCLC groups. A high proportion of SCLC patients with HHLA2-positive staining had a survival time <2 years. Neuron-specific enolase (NSE), CEA and Ki-67 levels were measured. The NSE level in the HHLA2-positive group was significantly greater than that in the HHLA2-negative group. The CEA and Ki-67 levels did not significantly differ between the HHLA2-positive and HHLA2-negative patients, nor were age, sex, smoking status, nodal metastasis status, Karnofsky Performance Scale (KPS) score, or Ki-67 expression score. HHLA2-positive SCLC patients had higher tumour stages and shorter 2-year survival times than HHLA2-negative patients did. Conclusion: The new immune molecule HHLA2 may be an ideal clinical biomarker for predicting SCLC progression and could serve as a new immunotherapy target in SCLC.

A Dietary Supplement Jinghuosu Ameliorates Reproductive Damage Induced by Tripterygium Glycosides.

OBJECTIVE: To determine the possible protective effects of Jinghuosu, a dietary supplement (DS), on tripterygium glycosides (TG)-induced reproductive system injury in rats and its underlying mechanisms. METHODS: A reproductive damage model was established in rats by feeding of TGs. Twenty-eight male Sprague Dawley rats were randomly divided into 4 groups using a random number table (n=7 in each): control (C) group, model (M) group, DS group and L-carnitine (LC) group. Rats in M, DS and LC groups received 40 mg/kg TGs orally. Starting from the 5th week, after administration of TGs for 4 h every day, rats in DS and LC groups were administered with 2.7 g/kg DS and 0.21 g/kg LC, respectively, for protective treatment over the next 4 weeks. Rats in Group C continued to receive the control treatment. Hematoxylin-eosin staining was used for histopathological analysis of rat testicular tissues. Enzyme-linked immunosorbent assay was performed to measure alkaline phosphatase (ALP), lactate dehydrogenase, alcohol dehydrogenase, total antioxidant capacity (T-AOC), superoxide dismutase, glutathione peroxidase (GSH-Px), and malondialdehyde (MDA) concentrations. Chemiluminescence assay was used to determine the serum testosterone content. Quantitative real-time PCR and Western blotting were conducted to analyze the expression of genes and proteins related to the testosterone synthesis pathway and the nuclear factor erythroid 2-related factor 2/heme oxygenase 1 antioxidant pathway. RESULTS: Oral administration of TGs induced significant increases in the testicular levels of zinc transporter 1 and MDA (P<0.05). On the other hand, sperm concentration, sperm motility, and serum testosterone, serum zinc, testicular zinc, Zrt-, Irt-like protein 1, ALP, luteinizing hormone (LH) receptor, steroidogenic acute regulatory protein, Cytochrome P450 family 11 subfamily A member 1, 3 ß -hydroxysteroid dehydrogenase 1 T-AOC, GSH-Px, nuclear factor erythroid 2-related factor 2, heme oxygenase-1 and NAD (P)H: quinone oxidoreductase 1 levels decreased following TGs exposure (P<0.05). All of these phenotypes were evidently reversed by DS (P<0.05). CONCLUSION: DS Jinghuosu protects against TG-induced reproductive system injury in rats, probably by improving zinc homeostasis, enhancing the testosterone synthesis and attenuating oxidative stress.

Mechanism of synergistic removal of NO and SO2 by sodium bicarbonate.

Sodium bicarbonate (NaHCO3) is considered to be an effective alkaline adsorbent for SO2 removal and surprisingly, the concentration of NO is significantly reduced along with the generation of NO2 during its desulfurization. Unfortunately, the mechanism of NO interaction with NaHCO3, SO2 and O2 is ambiguous. In this work, the effects of absorption gas and absorber composition on SO2/NO absorption performance were explored, the absorption products were characterized using XPS and SEM, and the Gibbs free energy of the inferred reaction path was calculated based on density functional theory (DFT). The results showed that SO2 and O2 synergistically promoted the absorption and removal of NO by NaHCO3, which could completely remove SO2 and absorb 90% of NO at 160 °C. Sodium metabisulfite (Na2S2O5) and sodium dithionate (Na2S2O6) were identified as the active substances responsible for efficient NO absorption, and the oxidation of Na2S2O5 to Na2S2O6 is the controlling step of the NO removal reaction. Specifically, Na2S2O5 is an intermediate produced by the reaction of NaHCO3 with SO2, and subsequently reacts with O2 to produce Na2S2O6, which releases reactive oxygen species to oxidize NO to NO2. In addition, when the S/N ratio is greater than 1 and the O2 content is greater than 5%, both SO2 and NO can maintain removal efficiency higher than 90%, indicating that the absorption reaction of SO2 and NO by NaHCO3 is highly adaptable to the flue gas composition.

Targeting Pericytes for Functional Recovery in Ischemic Stroke.

Pericytes surrounding endothelial cells in the capillaries are emerging as an attractive cell resource, which can show a large variety of functions in ischemic stroke, including preservation of the blood-brain barrier, regulation of immune function, and support for cerebral vasculature. These functions have been fully elucidated in previous studies. However, in recent years, increasing evidence has shown that pericytes play an important role in neurological recovery after ischemic stroke due to their regenerative function which can be summarized in two aspects according to current discoveries, one is that pericytes are thought to be multipotential themselves, and the other is that pericytes can promote the differentiation of oligodendrocyte progenitor cells (OPCs). Considering the neuroprotective treatment for stroke has not been much progressed in recent years, new therapies targeting pericytes may be a future direction. Here, we will review the beneficial effects of pericytes in ischemic stroke from two directions: the barrier and vascular functions and the regenerative functions of pericytes.

Altered microRNA expression profiles of human spermatozoa in normal fertile men of different ages.

MicroRNAs (miRNAs) are mediators of the aging process. The purpose of this work was to analyze the miRNA expression profiles of spermatozoa from men of different ages with normal fertility. Twenty-seven donors were divided into three groups by age (Group A, n = 8, age: 20-30 years; Group B, n = 10, age: 31-40 years; and Group C, n = 9, age: 41-55 years) for high-throughput sequencing analysis. Samples from 65 individuals (22, 22, and 21 in Groups A, B, and C, respectively) were used for validation by quantitative real-time polymerase chain reaction (qRT-PCR). A total of 2160 miRNAs were detected: 1223 were known, 937 were newly discovered and unnamed, of which 191 were expressed in all donors. A total of 7, 5, and 17 differentially expressed microRNAs (DEMs) were found in Group A vs B, Group B vs C, and Group A vs C comparisons, respectively. Twenty-two miRNAs were statistically correlated with age. Twelve miRNAs were identified as age-associated miRNAs, including hsa-miR-127-3p, mmu-miR-5100_L+2R-1, efu-miR-9226_L-2_1ss22GA, cgr-miR-1260_L+1, hsa-miR-652-3p_R+1, pal-miR-9993a-3p_L+2R-1, hsa-miR-7977_1ss6AG, hsa-miR-106b-3p_R-1, hsa-miR-186-5p, PC-3p-59611_111, hsa-miR-93-3p_R+1, and aeca-mir-8986a-p5_1ss1GA. There were 9165 target genes of age-associated miRNAs. Gene Ontology (GO) analysis of the target genes identified revealed enrichment of protein binding, membrane, cell cycle, and so on. The Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis of age-related miRNAs for target genes revealed 139 enriched pathways, such as signaling pathways regulating stem cell pluripotency, metabolic pathways, and the Hippo signaling pathway. This suggests that miRNAs play a key role in male fertility changes with increasing age and provides new evidence for the study of the mechanism of age-related male fertility decline.

Preparation of VOC low-temperature oxidation catalysts with copper and iron binary metal oxides via hydrotalcite-like precursors.

Catalysts are the key to catalytic combustion which is known as an effective method for VOC treatment of industrial waste gas. However, in a typical catalyst, the efficiency of non-noble catalysts, with well economic, is generally poor at catalytic oxidation of VOC from industrial waste gas. In this work, a non-noble catalyst CuFe-4.5 from Cu-Fe elements combined with the properties of hydrotalcite to successfully be prepared. The difference between hydrotalcite as a precursor catalyst and the traditional method was systematically investigated by XRD, FT-IR, SEM, TG, N2 adsorption-desorption isotherms, H2-TPR, O2-TPD, and XPS. By forming the hydrotalcite structure, the structural properties of the derivative oxide catalyst can be optimized and the interaction between Cu and Fe in the system can be strengthened. It is more prone to electrons cycle, has more chemically adsorbed oxygen, facilitates catalyst surface activation and shows better efficiency. The catalyst with high activity for VOC in flue gas at low temperature, with 90% conversion at 236 °C, which is about 60 °C lower than commercial catalysts such as EnviCat® from Clariant, Germany, and also has some advantages over current studies. Our study provides a new perspective on the design of efficient VOC catalysts.

Uniform H-CdS@NiCoP core-shell nanosphere for highly efficient visible-light-driven photocatalytic H2 evolution.

Constructing highly efficient and cost-effective photocatalyst system has been a big challenge for photocatalysis. Herein, CdS nanosphere (N-CdS), hollow CdS (H-CdS) and a series of H-CdS@NiCoP core-shell nanospheres have been successfully prepared via a facile hydrothermal method. The activity test showed that H-CdS exhibited higher photocatalytic activity (3.34 mmol g-1h-1) compared with N-CdS (0.99 mmol g-1h-1) under visible light irradiation (λ ≥ 420 nm), suggesting that hollow structure could effectively improve photocatalytic activity. Moreover, the H-CdS@NiCoP-7 wt% displayed a maximum photocatalytic H2 evolution rate of 13.47 mmol g-1h-1, which was about 4 times and 2.5 times higher than that of pristine H-CdS and H-CdS@Pt-3 wt%, respectively. Furthermore, H-CdS@NiCoP-7 wt% exhibited a good stability during 20 h test. The physicochemical properties were characterized by XRD, SEM, TEM, XPS, UV-vis DRS, PL and photoelectrochemical technique. The results showed that NiCoP addition can construct p-n junction with H-CdS and effectively promote the charge transfer from CdS to NiCoP, which improved the photocatalytic hydrogen evolution activity. This work revealed that NiCoP could react as an excellent co-catalyst for enhancing H-CdS photocatalytic activity.

[Establishment of a method for detection of thiols in seminal plasma and its application in patients with hyperuricemia].

OBJECTIVE: To establish a method of reversed-phase ultra-performance liquid chromatography with fluorescence (UPLC-FL) detection for simultaneous determination of homocysteine (Hcy), cysteine (Cys), cysteine glycine (CysGly) and glutathione (GSH) and analysis of the contents of the four thiols in the seminal plasma of normal men and patients with hyperuricemia (HUA). METHODS: Seminal plasma samples were collected from 30 normal sperm donors and 30 HUA patients and reduced with tris (2-carboxyethyl) phosphine hydrochloride. Then, the samples were subjected to protein precipitation with trichloroacetic acid solution, derivative reaction with 7-fluorobenzofuran-4-sulfate and isolation with a C18 column, with 0.025 mol/L KH2PO4 (pH 3.0) for mobile phase A and pure methanol for B, followed by equal gradient elution with an excitation wavelength of 380 nm and an emission wavelength of 510 nm. RESULTS: The correlation coefficients (R2) of the four thiols all exceeded 0.999, with an average recovery rate of 94.23－107.87%. Compared with the normal sperm donors, the HUA patients showed significantly increased contents of Cys (ï¼»108.01 ± 48.03ï¼½ vs ï¼»250.10 ± 55.87ï¼½ µmol/L, P < 0.05), Hcy (ï¼»113.97 ± 6.32ï¼½ vs ï¼»48.35 ± 15.07ï¼½ µmol/L, P < 0.05), and GSH (ï¼»3.15 ± 1.48ï¼½ vs ï¼»4.63 ± 1.17ï¼½ µmol/L, P < 0.05), but a decreased level of CysGly (ï¼»12.79 ± 3.18ï¼½ vs ï¼»5.94 ± 0.99ï¼½ µmol/L, P < 0.05). CONCLUSIONS: The method of reversed-phase UPLC-FL detection established in this study has made it possible simultaneous detection of Hcy, Cys, CysGly and GSH in the seminal plasma, which is applicable to laboratory research and clinical routine examination. Patients with hyperuricemia may incur oxidative damage to the reproductive system.

[Ultra-performance liquid chromatography for determination of the contents of biogenic amines in the seminal plasma].

OBJECTIVE: To establish an ultra-performance liquid chromatography (UPLC) method for determination of the contents of the three biogenic amines putacine, spermidine and spermine in human seminal plasma. METHODS: Seminal plasma samples were extracted with 5% trichloroacetic acid and processed by pre-column derivatization with dansyl chloride. Chromatographic separation was performed with a C18 (2.1×50 mm,1.7 µm) chromatographic column using water and acetonitrile for mobile-phase gradient elution at a flow rate of 0.3 ml/min, a detection wavelength of 245 nm, a column temperature of 35℃ and an injection volume was 3.0 µl. The contents of putacine, spermidine and spermine in the seminal plasma of 52 healthy sperm donors (the normal group) and 23 azoospermia patients (the AS group) were measured, and their correlation with routine semen parameters were analyzed. RESULTS: The three biogenic amines showed a good linearity (r ≥ 0.999), with a lower detection limit of 0.03－0.08 µg/ml. The relative standard deviation (RSD) of precision was ≤ 0.72% and the average recovery rate was 79.74%－108.87%. The normal group, compared with the AS patients, showed significantly higher contents of putrescine (ï¼»8.19 ± 7.85ï¼½ vs ï¼»2.43 ± 1.38ï¼½ mg/ml, P < 0.05), spermidine (ï¼»77.30 ± 32.58ï¼½ vs ï¼»31.99 ± 16.21ï¼½ mg/ml, P < 0.05) and spermine (ï¼»246.44 ± 83.99ï¼½ vs ï¼»166.15 ± 79.28ï¼½ mg/ml, P < 0.05). However, the contents of the three biogenic amines in the seminal plasma exhibited no significant correlation with the routine semen parameters in the normal group. CONCLUSIONS: The ultra-performance liquid chromatography method we established, with the advantages of high sensitivity and reproducibility and short peak-time, can quickly and accurately determine the contents of biogenic amines in the seminal plasma.

[Correlation of seminal plasma biochemical indexes with routine semen parameters in sperm donors].

OBJECTIVE: To investigate the relationship of seminal plasma biochemical indexes with routine semen parameters and that between seminal plasma biochemical indexes. METHODS: Using the automatic biochemical analyzer, we measured the contents of neutral α-glucosidase (NAG), fructose hexokinase (Fru) , citric acid (CA), acid phosphatase (ACP), (zinc) Zn, uric acid (UA), lactase dehydrogenase (LDH) and α-hydroxybutyrate dehydrogenase (α-HBDH) in the seminal plasma of 84 sperm donors in the Human Sperm Bank of Hebei Province. We analyzed the correlation between these indexes and that between routine semen parameters and these indexes. RESULTS: Sperm concentration and total sperm count were correlated positively with the contents of seminal plasma NAG, ACP, Zn, CA, LDH and α-HBDH (P<0.05) but negatively with Fru (P<0.05), the percentage of progressively motile sperm positively with seminal plasma Zn (P<0.05), and CA positively with NAG, Zn, LDH, α-HBDH and ACP (P<0.01) but negatively with Fru (P<0.01), NAG positively with Zn, LDH, α-HBDH and ACP (P<0.05) but Fru negatively with ACP (P<0.01), Zn positively with LDH, α-HBDH and ACP (P<0.01), and LDH positively with α-HBDH and ACP (P<0.01) but UA negatively with ACP (P<0.05). CONCLUSIONS: Biochemical indexes in the seminal plasma of healthy men are not only closely related to each other, but also to some routine semen parameters.

Dual-site electrocatalytic nitrate reduction to ammonia on oxygen vacancy-enriched and Pd-decorated MnO2 nanosheets.

Electrocatalytic nitrate reduction (NRR) represents one promising alternative to the Haber-Bosch process for NH3 production due to the lower reaction energy barrier compared to N2 reduction and the potential recycling of nitrogen source from nitrate wastewater. The metal oxides with oxygen vacancy (Ov) display high NH3 selectivities in NRR (NO2-/N2 as side products), but the complexity in Ov enrichment and the inferior hydrogen adsorption on oxides make NRR an inefficient process. Herein, one superior dual-site NRR electrocatalyst that is composed of Ov-enriched MnO2 nanosheets (MnO2-Ov) and Pd nanoparticles (deposited on MnO2) is constructed over the three-dimensional porous nickel foam (Pd-MnO2-Ov/Ni foam). In a continuous-flow reaction cell, this electrode delivers a NO3--N conversion rate of 642 mg N m-2electrode h-1 and a NH3 selectivity of 87.64% at -0.85 V vs. Ag/AgCl when feeding 22.5 mg L-1 of NO3--N (0.875 mL min-1), outperforming the Pd/Ni foam (369 mg N m-2electrode h-1, 85.02%) and MnO2-Ov/Ni foam (118 mg N m-2electrode h-1, 32.25%). Increasing the feeding NO3--N concentration and flow rate to 180.0 mg L-1 and 2.81 mL min-1 can further lift the conversion rate to 1933 and 1171 mg N m-2electrode h-1, respectively. The combination of experimental characterizations and theoretical calculations reveal that the MnO2-Ov adsorbs, immobilizes, and activates the NO3- and N-intermediates, while the Pd supplies the Ov sites with sufficient adsorbed hydrogen (H*) for both the NRR and Ov refreshment. Our work presents a good example of utilizing dual-site catalysis in the highly selective conversion of NO3- to NH3 that is important for nitrate pollution abatement, nitrogen resource recycling, as well as sustainable NH3 production.

Density functional theory study of active sites on nitrogen-doped graphene for oxygen reduction reaction.

Oxygen reduction reaction (ORR) remains challenging due to its complexity and slow kinetics. In particular, Pt-based catalysts which possess outstanding ORR activity are limited in application with high cost and ease of poisoning. In recent years, nitrogen-doped graphene has been widely studied as a potential ORR catalyst for replacing Pt. However, the vague understanding of the reaction mechanism and active sites limits the potential ORR activity of nitrogen-doped graphene materials. Herein, density functional theory is used to study the reaction mechanism and active sites of nitrogen-doped graphene for ORR at the atomic level, focusing on explaining the important role of nitrogen species on ORR. The results reveal that graphitic N (GrN) doping is beneficial to improve the ORR performance of graphene, and dual-GrN-doped graphene can demonstrate the highest catalytic properties with the lowest barriers of ORR. These results provide a theoretical guide for designing catalysts with ideal ORR property, which puts forward a new approach to conceive brilliant catalysts related to energy conversion and environmental catalysis.

Dynamin-2 mediates clathrin-dependent endocytosis for amyloid-ß internalization in brain microvascular endothelial cells.

Dynamin is recognized as a crucial regulator for membrane fission and has three isoforms in mammals. But the expression patterns of dynamin isoforms and their roles in non-neuronal cells are incompletely understood. In this study, the expression profiles of dynamin isoforms and their roles in endocytosis was investigated in brain endothelial cells. We found that Dyn2 was expressed at highest levels, whereas the expression of Dyn1 and Dyn3 were far less than Dyn2. Live-cell imaging was used to investigate the effects of siRNA-mediated knockdown of individual dynamin isoforms on transferrin uptake, and we found that Dyn2, but not Dyn1 or Dyn3, is required for the endocytosis in brain endothelial cells. Results of dextran uptake assay showed that dynamin isoforms are not involved in the clathrin-independent fluid-phase internalization of brain endothelial cells, suggesting the specificity of the role of Dyn2 in clathrin-dependent endocytosis. Immunofluorescence and electron microscopy analysis showed that Dyn2 co-localizes with clathrin and acts at the late stage of vesicle fission in the process of endocytosis. Further results showed that Dyn2 is necessary for the basolateral-to-apical internalization of amyloid-ß into brain endothelial cells. We concluded that Dyn2, but not Dyn1 or Dyn3, mediates the clathrin-dependent endocytosis for amyloid-ß internalization particularly from basolateral to apical side into brain endothelial cells.

p-n Heterojunction Photocatalyst Mn0.5Cd0.5S/CuCo2S4 for Highly Efficient Visible Light-Driven H2 Production.

It is highly important to develop efficient and cheap photocatalysts for hydrogen production. Herein, a series of p-n heterojunction Mn0.5Cd0.5S/CuCo2S4 has been successfully synthesized for the first time by the hydrothermal impregnation method. Mn0.5Cd0.5S/CuCo2S4 loading with 12 wt % CuCo2S4 shows the highest H2 evolution rate of 15.74 mmol h-1 g-1 under visible light (λ ≥ 420 nm) irradiation, which is about 3.15 and 15.28 times higher than that of bare Mn0.5Cd0.5S (4.99 mmol h-1 g-1) and CuCo2S4 (1.03 mmol h-1 g-1), respectively. In addition, it shows a relatively good stability during the five recycle tests, with about 20% loss of reaction rate compared to that of the first cycle. The superior photocatalytic performance is attributed to the effective separation and transfer of photogenerated charge carriers because of the formation of the p-n junction. The samples are systematically characterized by X-ray diffraction, ultraviolet-visible (UV-vis), diffuse reflectance spectroscopy, scanning electron microscopy, transmission electron microscopy (TEM), high-resolution TEM, X-ray photoelectron spectroscopy, photoluminescence, EIS, and so on. UV-vis and EIS show that CuCo2S4 can effectively improve the visible light response of Mn0.5Cd0.5S/CuCo2S4 and promote the electron transfer from CuCo2S4 to the conduction band of Mn0.5Cd0.5S, so as to improve the photocatalytic efficiency. This study reveals that the p-n heterojunction Mn0.5Cd0.5S/CuCo2S4 is a promising photocatalyst to explore the photocatalysts without noble metals.