Development and characterization of an antibody that recognizes influenza virus N1 neuraminidases.

Influenza A viruses (IAVs) continue to pose a huge threat to public health, and their prevention and treatment remain major international issues. Neuraminidase (NA) is the second most abundant surface glycoprotein on influenza viruses, and antibodies to NA have been shown to be effective against influenza infection. In this study, we generated a monoclonal antibody (mAb), named FNA1, directed toward N1 NAs. FNA1 reacted with H1N1 and H5N1 NA, but failed to react with the NA proteins of H3N2 and H7N9. In vitro, FNA1 displayed potent antiviral activity that mediated both NA inhibition (NI) and blocking of pseudovirus release. Moreover, residues 219, 254, 358, and 388 in the NA protein were critical for FNA1 binding to H1N1 NA. However, further validation is necessary to confirm whether FNA1 mAb is indeed a good inhibitor against NA for application against H1N1 and H5N1 viruses.

Mechanism of ß-blocker biodegradation by wastewater microorganisms.

The recalcitrant ß-blockers have been widely detected in aquatic environments up to several hundred µg/L, which are major contributors to ß1 antagonistic activities in wastewater. Their biodegradation mechanisms remain obscure, hindering the development of efficient removal techniques. This study constructed the biodegradation pathways for three typical ß-blockers, namely atenolol, metoprolol, and propranolol, assessed the toxicity of their major biotransformation products, and identified the key enzyme catalyzing the O-dealkylation reaction leading to pollutant mineralization. Atenolol and metoprolol degradation was more efficient than that of propranolol by activated sludge, producing metoprolol acid (MTPA) as a major intermediate. Hydrogenophaga sp. YM1 isolated from activated sludge possess the α-ketoglutarate dependent dioxygenase (TfdA) responsible for O-dealkylation of MTPA and propranolol, producing 4-hydroxyphenylacetic acid (4-HPA) that can be further degraded and ultimately enters the TCA cycle. The role of TfdA was verified by proteomics, enzyme stimulation/inhibition tests, and gene knockout experiments. Molecular docking suggests its different interactions with MTPA and propranolol. Acetate facilitated the degradation of ß-blockers efficiently. The results may shed light on enhanced biological removals of broader ß-blockers and their transformation products in the environment.

Active assimilators of soluble microbial products produced by wastewater anammox bacteria and their roles revealed by DNA-SIP coupled to metagenomics.

Heterotrophic bacteria grow on influent organics or soluble microbial products (SMP) in wastewater anammox processes, playing key roles in facilitating microbial aggregation and reducing excess nitrate. The overgrowth of heterotrophs represents one of the major causes of anammox process failure, while the metabolic functions of coexisting heterotrophs and their roles in anammox process remain vague. This study aimed at revealing metabolic interactions between AnAOB and active SMP assimilators by integrating 13C DNA-stable isotope probing, metabolomic and metagenomic approaches. Glycine, aspartate, and glutamate with low biosynthetic energy cost were the major SMP components produced by AnAOB (net yield: 44.8, 10.4, 8.1 mg·g NH4+-N-1). Glycine was likely synthesized by AnAOB via the reductive glycine pathway which is oxygen-tolerant, supporting heterotrophic growth. Fermentative Chloroflexi bacterium OLB13, denitrifying Gemmatimonadaceae and Burkholderiaceae bacterium JOSHI-001 were active SMP assimilators, which were prevalent in globally distributed wastewater anammox reactors as core taxa. They likely formed a mutualistic relationship with auxotrophic Ca. Kuenenia by providing necessities such as methionine, folate, 4'-phosphopantetheine, and molybdopterin cofactor, and receiving vitamin B12 for methionine synthesis. For the first time, the identify and metabolic features of SMP assimilators in wastewater anammox communities were revealed. Supplying necessities secreted by heterotrophs could be helpful to the endeavor of AnAOB enrichment. Practically, maintaining active but not overgrown SMP assimilators is critical to efficient and stable operation of wastewater anammox processes.

Low strength wastewater anammox start-up by stepwise decrement in influent nitrogen: Biofilm formation mechanism and mathematical modelling.

The application of mainstream anammox process is hampered by its overlong start-up and instability under disturbance. A lab-scale mainstream anammox moving bed biofilm reactor (MBBR) was successfully started in 120 days with stepwise decrement in influent nitrogen concentration from sidestream to mainstream condition. The initial colonization by Candidatus Jettenia and filamentous fermenter Anaerolineaceae were potentially mediated by hydrophobic interaction and type IV pilus. Ca. Kuenenia with higher substrate affinity outcompeted Ca. Jettenia, and the predominant fermenters shifted to fermentative Ignavibacteriaceae in the mature biofilm. A novel mainstream anammox biofilm development (MABD) model was constructed to describe biofilm growth, population dynamics, and nitrogen removal performance. The simulation results suggested that higher inocula biomass (460-690 mgVSS·L-1), relative abundance of low-affinity AnAOB in the inocula (e.g., Ca. Jettenia, 1.3-2%), and the early-stage solids retention time (45-68 days) were desired to form thicker biofilm and improve effluent quality during 120-day mainstream anammox MBBR start-up. The mechanistic insights into biofilm formation and predictive power of the newly developed MABD model are of importance to the design and operation of mainstream anammox processes towards more biofilm biomass and higher nitrogen removal efficiency.

Effects of A-site non-stoichiometry in YxInO3+δ on the catalytic performance during methane combustion.

A novel non-stoichiometric YxInO3+δ (YIO-x, 0.8 ≤ x ≤ 1.04) perovskite catalyst with a large number of oxygen vacancies and high specific surface area was synthesized using glycine self-propagating gel combustion. It was found that low levels of non-stoichiometry in the A site of YxInO3+δ effectively increased the amount of oxygen desorption by 39-42% when compared to the original (YIO-1) due to Y-deficiency and oxygen vacancies. Further investigations showed that the non-stoichiometry also brings a significant change to the Lewis acid sites on the surface of the sample, which confirmed to be a great promoter for the catalytic combustion of methane. In addition, the catalytic performance increased with the increasing intensity of acid sites. After 50 h of the stability test, the catalysts maintained high activity, indicating their good catalytic stability.

Carbon quantum dot tailored counter electrode for 7.01%-rear efficiency in a bifacial dye-sensitized solar cell.

We present here a carbon quantum dot (CQD) tailored counter electrode (CE) for a bifacial dye-sensitized solar cell (DSSC). Arising from wide spectral absorption, high optical transmission and the electron-enriched surface of the CE, the final bifacial DSSC device yields front and rear efficiencies of 9.08% and 7.01%, respectively.

Association of choroidal thickness with early stages of diabetic retinopathy in type 2 diabetes.

AIM: To assess the correlation between choroidal thickness (CT) and the early stages of diabetic retinopathy (DR) in type 2 diabetic patients. METHODS: We divided 83 diabetic patients (51-80 years of age; 50 females) into non diabetic retinopathy group (NDR) and mild/moderate nonproliferative diabetic retinopathy (NPDR) group, and compared them with 26 non-diabetic control subjects (51-78 years of age; 16 females). Subfoveal choroidal thickness (SFCT) and parafoveal choroidal thickness (PFCT) were measured using enhanced depth imaging spectral-domain optical coherence tomography (EDI-OCT). Ocular health status, disease duration, body mass index, and hemoglobin A1c (HbA1c) were recorded. RESULTS: The mean ages of the NDR, NPDR, and control groups were 68.0±6.9y, 67.8±6.4y, and 65.1±6.3y, respectively (P=0.17). Pearson correlation of the right and left eyes for the control subjects was 0.95 and for the NDR subjects was 0.93. SFCT for the right eyes of the controls was 252.77± 41.10 µm, which was significantly thicker than that of the right eyes in NDR group (221.51±46.56 µm) and the worse eyes of the NPDR group (207.18±61.87 µm; ANOVA, P<0.01). In the diabetic patients pooled together, age was the only variable significantly associated with SFCT (multiple linear regression analysis, P=0.01). CONCLUSION: CT decreased significantly in the NDR and mild/moderate NPDR eyes compared with the control eyes. Age is significantly associated with SFCT in the diabetic patients. Diabetic choroidopathy may be present before clinical retinopathy.

Rapid Conversion from Carbohydrates to Large-Scale Carbon Quantum Dots for All-Weather Solar Cells.

A great challenge for state-of-the-art solar cells is to generate electricity in all weather. We present here the rapid conversion of carbon quantum dots (CQDs) from carbohydrates (including glucose, maltol, sucrose) for an all-weather solar cell, which comprises a CQD-sensitized mesoscopic titanium dioxide/long-persistence phosphor (m-TiO2/LPP) photoanode, a I-/I3- redox electrolyte, and a platinum counter electrode. In virtue of the light storing and luminescent behaviors of LPP phosphors, the generated all-weather solar cells can not only convert sunlight into electricity on sunny days but persistently realize electricity output in all dark-light conditions. The maximized photoelectric conversion efficiency is as high as 15.1% for so-called all-weather CQD solar cells in dark conditions.

A simulation study of the impact of the public-private partnership strategy on the performance of transport infrastructure.

The choice of investment strategy has a great impact on the performance of transport infrastructure. Positive projects such as the "Subway plus Property" model in Hong Kong have created sustainable financial profits for the public transport projects. Owing to a series of public debt and other constraints, public-private partnership (PPP) was introduced as an innovative investment model to address this issue and help develop transport infrastructure. Yet, few studies provide a deeper understanding of relationships between PPP strategy and the performance of such transport projects (particularly the whole transport system). This paper defines the research scope as a regional network of freeway. With a popular PPP model, travel demand prediction method, and relevant parameters as input, agents in a simulation framework can simulate the choice of PPP freeway over time. The simulation framework can be used to analyze the relationship between the PPP strategy and performance of the regional freeway network. This study uses the Freeway Network of Yangtze River Delta (FN-YRD) in China as the context. The results demonstrate the value of using simulation models of complex transportation systems to help decision makers choose the right PPP projects. Such a tool is viewed as particularly important given the ongoing transformation of functions of the Chinese transportation sector, including franchise rights of transport projects, and freeway charging mechanism.

[A survey of vision-related quality of life in patients with exudative age-related macular degeneration].

OBJECTIVE: To evaluate the vision-related quality of life in patients with exudative age-related macular degeneration (AMD). METHODS: Retrospective case-series study.One hundred and twenty-two patients with exudative AMD who were treated in Beijing Tongren Eye Center from July 2007 to July 2008 were invited to participate in this study.Vision-related quality of life was evaluated by the 25-item National Eye Institute Visual Functioning Questionnaire.Statistical analysis was performed using t test for data which were normal distribution and using Wilcoxon rank sum test for data which were abnormal distribution. RESULTS: Eighty-seven cases were fully completed and included in the final analysis within the 122 questionnaires. The total score of the questionnaire was 57.2 ± 18.4, excluded driving item. The lowest scoring item was near activities with mean score of 30.8 ± 22.3. There was statistically significant difference in mental health between male (52.9 ± 26.3) and female (40.8 ± 26.0) (w = 1 175, P < 0.05). Except for the general health and ocular pain, patients with binocular involvement showed statistically significant lower scores than those with monocular involvement in all other subscales (P < 0.05). The two age groups (patients <65 vs. ≥ 65 years old) in binocular involvement group showed statistically significant difference only in the subscale of social activities (56.6 ± 22.2 vs.42.3 ± 30.2) (w = 97, P = 0.013). CONCLUSIONS: This study suggests that exudative AMD damaged patients'near activities seriously.Female patients tends to have lower scores than male in mental health. The score of patients with binocular involvement is lower than that of patients with monocular involvement. Age has significant effects on the social activities of those patients with binocular involvement.