Enhancing Localized Electron Density over Pd1.4Cu Decorated Oxygen Defective TiO2-x Nanoarray for Electrocatalytic Nitrite Reduction to Ammonia.

Electrocatalytic nitrite (NO2 -) reduction to ammonia (NH3) is a promising method for reducing pollution and aiding industrial production. However, progress is limited by the lack of efficient selective catalysts and ambiguous catalytic mechanisms. This study explores the loading of PdCu alloy onto oxygen defective TiO2-x, resulting in a significant increase in NH3 yield (from 70.6 to 366.4 µmol cm-2 h-1 at -0.6 V vs reversible hydrogen electrode) by modulating localized electron density. In situ and operando studies illustrate that the reduction of NO2 - to NH3 involves gradual deoxygenation and hydrogenation. The process also demonstrated excellent selectivity and stability, with long-term durability in cycling and 50 h stability tests. Density functional theory (DFT) calculations elucidate that the introduction of PdCu alloys further amplified electron density at oxygen vacancies (Ovs). Additionally, the Ti─O bond is strengthened as the d-band center of the Ti 3d rising after PdCu loading, facilitating the adsorption and activation of *NO2. Moreover, the presence of Ovs and PdCu alloy lowers the energy barriers for deoxygenation and hydrogenation, leading to high yield and selectivity of NH3. This insight of controlling localized electron density offers valuable insights for advancing sustainable NH3 synthesis methods.

Preparation of magnetically separable and low-cost MC-FePd3NPs with enhanced catalytic activity in the reduction of p-nitrophenol.

To obtain a magnetically separable, low-cost and highly efficient reduction catalyst, microbial carbon-loaded bimetallic palladium/iron nanoparticles (MC-FePd3NPs) were synthesized in this study by using waste yeast residue doped with iron during the preparation process of microbial carbon-loaded monometallic palladium nanoparticles (MC-Pd NPs). The morphology, crystal structure, magnetic properties and catalytic performance of MC-FePd3NPs for the reduction ofp-nitrophenol (p-NP) were investigated by various characterization techniques, such as SEM-EDS, TEM, XRD, PPMS-9 and UV-vis spectroscopy. The catalytic experiments showed that the MC-FePd3NPs prepared under pyrolysis conditions at 700 °C had an apparent rate constant of 1.85 × 10-1s-1which is better than the rate constants of MC-Pd NPs and other palladium-based nanocatalytic materials reported so far. The amount of palladium used in the synthesis of MC-FePd3NPs was half that of MC-Pd NPs. The catalyst exhibited soft magnetic ordering behavior and still showed a catalytic efficiency of 97.4% after five consecutive reaction cycles. Furthermore, employing MC-FePd3NPs reduces the costs of catalyst preparation and use in production. MC-FePd3NPs with efficient catalytic properties, facile magnetic separation and recyclability, and low costs of preparation and use have considerable potential for industrial applications.

How nutrient loads influence microbial-derived carbon accumulation in wetlands: A new insight from microbial metabolic investment strategies.

Excessive anthropogenic nutrient inputs often lead to the degradation of wetland ecosystems and a decrease in carbon sink capacity. Microbial-derived carbon is increasingly recognized as an important precursor for organic carbon formation, which is controlled by the balance between microbial anabolic and catabolic processes. Shifts in microbial metabolic investment under nutrient load disturbance are key, but understudied, components of microbial-derived carbon turnover. Here, the roles of the distinct life-history traits and cooperation degree of key microbial assemblies in regulating microbial-derived carbon accumulation in a wetland receiving treated wastewater were firstly assessed by combining microbial biomarkers and genomic approaches. It was found that microbial-derived carbon was an important source of organic carbon in wetlands, and strongly associated with several microbial assemblies with specific trait strategies. Further analysis demonstrated that high growth yield strategists were mainly associated with microbial necromass accrual, while microbial biomass was more dominated by resource acquisition strategies in nutrient-imbalanced wetlands. A significant positive relationship between positive cohesion and microbial-derived carbon indicated that cooperative behavior among taxa promoted the production and accumulation of microbial-derived carbon. Moreover, resource stoichiometric balance, including C:N and C:P, was identified as an important driver of shifts in microbial metabolic investment strategies. The decreased C:N ratio led to a shift from resource acquisition strategies to high growth yield strategies for the microbial community, which facilitated microbial necromass accrual along the N-limited wetland, while the increased C:P ratio caused by excessive P deposition in sediments limits microbial cooperative growth to some extent. This study highlighted the importance of stoichiometric balance in mediating microbial growth metabolism and, in turn, enhancing the carbon sink capacity of wetlands.

Bacterial and fungal assemblages and functions associated with biofilms differ between diverse types of plastic debris in a freshwater system.

Once in aquatic ecosystems, plastics can be easily colonized by diverse microbes, and these microbial communities on plastics-the 'plastisphere'-often differ from the communities in the surrounding water and other substrates. However, our knowledge of plastic-associated bacterial and fungal communities on diverse plastics in freshwater is poor, especially for fungal communities. Furthermore, intraspecies interactions among bacterial and fungal communities colonized on diverse plastics are poorly known. Here, we characterized the taxonomic composition and diversity of bacteria and fungi on three types of plastics in a lab-scale incubator with freshwater from an urban river. High-throughput sequencing revealed that the alpha diversity of bacterial communities was higher on polyethylene microplastics (MPs) than on polyethylene (PE) and polypropylene (PP) sheets. The structure of bacterial communities on MPs differed from those on plastic sheets. In contrast, no striking differences in alpha diversity and taxonomic composition were observed for fungal communities on different types of plastics. Members of Ascomycota, Basidiomycota, Blastocladiomycota and Mucoromycota dominated fungal assemblages on plastics. Co-occurrence network analysis revealed that the biotic interactions between bacteria and fungi on MPs were less complex than those on PE and PP sheets. The three types of plastics shared no keystone taxa. The functional profiles (KEGG) predicted by Tax4Fun showed that the pathways of alanine, aspartate, glutamate and biotin metabolism were enriched in biofilms on MPs. Nonetheless, the higher complexity of plastic sheet-associated biofilms might make them more resistant to environmental perturbation and facilitate the maintenance of microbial activities.

Expression and Clinical Significance of Mucin Gene in Chronic Rhinosinusitis.

PURPOSE OF REVIEW: This review highlights the expression and regulation of mucin in CRS and discusses its clinical implications. RECENT FINDINGS: Chronic rhinosinusitis (CRS) is common chronic nasal disease; one of its main manifestations and important features is mucus overproduction. Mucin is the major component of mucus and plays a critical role in the pathophysiological changes in CRS. The phenotype of CRS affects the expression of various mucins, especially in nasal polyps (NP). Corticosteroids(CS), human neutrophil elastase (HNE), and transforming growth factor-ß1 (TGF-ß1) are closely related to the tissue remodeling of CRS and regulate mucin expression, mainly MUC1, MUC4, MUC5AC, and MUC5B. "It is expected that CS, HNE and TGF - ß could be used to regulate the expression of mucin in CRS." However, at present, the research on mucin is mainly focused on mucin 5AC and mucin 5B, which is bad for finding new therapeutic targets. Investigating the expression and location of mucin in nasal mucosa and understanding the role of various inflammatory factors in mucin expression are helpful to figure out regulatory mechanisms of airway mucin hypersecretion. It is of great significance for the treatment of CRS.

Alternative states in microbial communities during artificial aeration: Proof of incubation experiment and development of recurrent neural network models.

Artificial aeration, a widely used method of restoring the aquatic ecological environment by enhancing the re-oxygenation capacity, typically relies upon empirical models to predict ecological dynamics and determine the operating scheme of the aeration equipment. Restoration through artificial aeration is involved in oxic-anoxic transitions, whether these transitions occurred in the form of a regime shift, making the development of predictive models challenging. Here, we confirmed the existence of alternative states in microbial communities during artificial aeration through aeration incubation experiment for the first time and considered its existence in neural network modeling in order to improve model performance. By aeration incubation experiment, it was confirmed that the alternative states exist in microbial communities during artificial aeration by two independent approaches, potential analysis and "enterotyping" approach. Comparing neural network models with and without considering the existence of alternative states, it was found that considering the existence of alternative states in modeling could improve the performance of neural network model. Our study provides a reference for the prediction of systems containing time series data where the current state will have an impact on later states. The developed model could be used for optimizing the operating scheme of the artificial aeration.

The Prevalence, Coinfection, and Evolutionary and Molecular Characteristics of Prevalent Goose Circovirus in Guangdong, China.

To understand the prevalence, coinfection with other viruses, underlying genetic evolution, recombination, and molecular biological characteristics of goose circovirus (GoCV) in Guangdong, China, from December 2019 to August 2020, 310 tissue samples of geese showing stunted growth and feather disorder syndrome were collected from this region and analyzed. GoCV, Tembusu virus, waterfowl paramyxovirus, avian influenza virus, fowl adenovirus type 4, and duck plague virus were detected with PCR or real-time PCR. Thirty-one complete GoCV viral genomes were obtained from 164 PCR-verified GoCV nucleotide-positive samples and subjected to phylogenetic analysis, gene recombination analysis, and genome secondary structure prediction. The results showed that more than half of the samples were GoCV positive, and 31.1% of the GoCV-positive samples were from coinfections with at least one of the other viruses. The phylogenetic analysis showed that the GoCVs could be divided into three genome types. The genes of most main epidemic strains now circulating in Guangdong belonged to the Ia subtype, and some strains gradually formed a new Ib subtype. The secondary structure of the viral genome was similar to that of other known circoviruses. Furthermore, B cell linear epitope prediction and protein structure homology modeling of the viral capsid protein were performed based on the viral amino acid sequences. The results showed that the spatial structure of the capsid protein of the 31 sequenced strains was similar to that of duck circovirus and consisted of two ß-sandwich conformations. A total of five B cell linear epitopes were predicted, and four of them were mapped on the predicted model of the capsid protein of GoCVs. This report provides a reference for the epidemiology of GoCV in Guangdong, understanding the elemental composition of the virus genes and proteins, selecting representative vaccine strains, constructing targeted immune preparations for GoCV, and strengthening prevention and control of the disease.

Prevalencia, coinfección y características evolutivas y moleculares del circovirus del ganso prevalente en Guangdong, China. Para comprender la prevalencia, la coinfección con otros virus, su evolución genética subyacente, la recombinación y las características biológicas moleculares del circovirus del ganso (GoCV) en Guangdong, China, de diciembre de 2019 a agosto de 2020, 310 se recolectaron muestras de tejido de gansos que presentaban retraso en el crecimiento y síndrome del trastorno de las plumas en esta región y fueron analizadas. Se detectaron mediante PCR o por PCR en tiempo real el circovirus del ganso, el virus Tembusu (TMUV), el paramixovirus de aves acuáticas (WFPV), el virus de la influenza aviar (AIV), el adenovirus del pollo tipo 4 (Fadv-4) y el virus de la enteritis viral del pato (DPV). Se obtuvieron 31 genomas virales completos del circovirus del ganso de 164 muestras positivas de nucleótidos de circovirus del ganso verificadas por PCR y se sometieron a análisis filogenético, a análisis de recombinación de genes y predicción de la estructura secundaria del genoma. Los resultados mostraron que más de la mitad de las muestras eran positivas para circovirus del ganso y el 31.1% de las muestras positivas para circovirus del ganso eran de coinfecciones con al menos uno de los otros virus. El análisis filogenético mostró que los circovirus del ganso podrían dividirse en tres tipos de genomas. Los genes de la mayoría de las principales cepas epidémicas que ahora circulan en Guangdong pertenecían al subtipo Ia, y algunas cepas formaron gradualmente un nuevo subtipo Ib. La estructura secundaria del genoma viral era similar a la de otros circovirus conocidos. Además, la predicción del epítope lineal de células B y el modelo de la homología de la estructura de la proteína de la cápside viral se realizaron basándose en las secuencias de aminoácidos virales. Los resultados mostraron que la estructura espacial de la proteína de la cápside de las 31 cepas secuenciadas era similar a la del circovirus de pato y consistía de dos conformaciones de tipo sándwich ß. Se predijo un total de cinco epítopes lineales de células B y cuatro de ellos se mapearon en el modelo predicho de la proteína de la cápside del circovirus del ganso. Este informe proporciona una referencia para la epidemiología de circovirus del ganso en Guangdong, entendiendo la composición elemental de los genes y proteínas del virus, seleccionando cepas de vacunas representativas, construyendo preparaciones de blancos inmunitarios para circovirus del ganso y fortaleciendo la prevención y el control de la enfermedad.