Runoff regulation and nitrogen and phosphorus removal performance of a bioretention substrate with HDTMA-modified zeolite

As a commonly used material in bioretention substrates, natural zeolite (NZ) provides decent adsorption capacity for cation pollutants and heavy metals, but limited ability to remove anion pollutants. Hexadecyltrimethylammonium bromide (HDTMA)-modified zeolite (MZ) was used as the bioretention substrate material. The performance of the media including runoff reduction, nitrate nitrogen (NO3−-N) removal, ammonium nitrogen (NH4+-N) removal, and total phosphorus (TP) removal was assessed by the column experiment. The effects of different levels of modification, ratio of zeolite in the substrate, and rainfall intensity on media performance were investigated. The results indicate that HDTMA-modified zeolite significantly improves the NO3−-N (up to 38.2 times of NZ) and TP (up to17.5 times of NZ) removal rate of media and slightly increases the NH4+-N (up to 1.5 times of NZ) purification performance of the substrate. Compared with the media with NZ, decline on both runoff volume reduction (maximum decline up to 32.9%) and flow rate reduction (maximum decline up to 29.9%) of the media with MZ were observed. Based on multiple regression analysis, quantitative relationship models between influencing factors and response variables were established (R2 > 0.793), the level of the effect of influencing factors on response variables was investigated, and the interactions between influencing factors were explored. The main effect analysis found that the degree of modification affects NO3−-N and TP removal rate of the substrate the most, and when the amount of HDTMA molecules loaded on the zeolite surface exceeds 0.09meq/g, the modification can no longer improve NO3−-N removal efficiency

Assessing the Effectiveness of Direct Data Merging Strategy in Long-Term and Large-Scale Pharmacometabonomics

Because of the extended period of clinic data collection and huge size of analyzed samples, the long-term and large-scale pharmacometabonomics profiling is frequently encountered in the discovery of drug/target and the guidance of personalized medicine. So far, integration of the results (ReIn) from multiple experiments in a large-scale metabolomic profiling has become a widely used strategy for enhancing the reliability and robustness of analytical results, and the strategy of direct data merging (DiMe) among experiments is also proposed to increase statistical power, reduce experimental bias, enhance reproducibility and improve overall biological understanding. However, compared with the ReIn, the DiMe has not yet been widely adopted in current metabolomics studies, due to the difficulty in removing unwanted variations and the inexistence of prior knowledges on the performance of the available merging methods. It is therefore urgently needed to clarify whether DiMe can enhance the performance of metabolic profiling or not. Herein, the performance of DiMe on 4 pairs of benchmark datasets was comprehensively assessed by multiple criteria (classification capacity, robustness and false discovery rate). As a result, integration/merging-based strategies (ReIn and DiMe) were found to perform better under all criteria than those strategies based on single experiment. Moreover, DiMe was discovered to outperform ReIn in classification capacity and robustness, while the ReIn showed superior capacity in controlling false discovery rate. In conclusion, these findings provided valuable guidance to the selection of suitable analytical strategy for current metabolomics

Nanoporous PdCu alloy with enhanced electrocatalytic performance

Nanoporous PdCu alloys (NP-PdCu) with uniform PdCu alloy ligament (~6 nm) and predetermined bimetallic ratio are prepared by selectively dealloying PdCuAl ternary alloys in an alkaline solution. NP-PdCu exhibit greatly enhanced electrocatalytic activity for formic acid and methanol oxidation compared with nanoporous Pd (NP-Pd). Moreover, the structure stability of NP-PdCu is also greatly enhanced. The electrochemical surface area of NP-PdCu is well-maintained after 10,000 potential cycles from 0.6 to 0.9 V (vs. RHE) in 0.5 M H2SO4 aqueous solution, while that of NP-Pd drops dramatically after 5000 cycles. The NP-PdCu will be promising anode catalysts for fuel cell-related technology. Keywords: Dealloying, Fuel cell, Stabilit

Enhance the ethanol fermentation performance of kitchen waste using microwave pretreatment

Pretreatment is considered to be one of the key steps to improve the bioavailability and fermentability of kitchen waste (KW). In this article, microwave pretreatment was used for the enzymatic saccharification and ethanol fermentation of KW. The optimal pretreatment parameters were determined as mixing KW with water at a solid-to-liquid ratio (S/L) of 1:5 and pretreating at 19.2 W/g for 6 min. The obtained reducing sugar yield in the enzymatic hydrolysate of the KW pretreated by optimal parameters was 0.721 g/g TS. For separate enzymatic hydrolysis and fermentation (SHF), the final ethanol yield at 21 h using enzymatic hydrolysate of microwave-pretreated KW (MWKW) as substrate was 0.344 g/g TS (equivalent to 93.1% of the theoretical ethanol yield). It was 52.2% higher than that using the hydrolysate of un-pretreated KW as substrate. For simultaneous enzymatic hydrolysis and fermentation (SSF), the final ethanol yield generated from MWKW was 0.269 g/g TS, which was only 6.3% higher than that generated from un-pretreated KW. The microstructure of KW was observed using SEM, which indicated that the demulsification of lipid and the structural rupture of the starch granules and fibers under the effect of microwave would result in the rough and porous structures of MWKW and thereby improving the bioavailability and fermentability of KW. These results indicate that microwave pretreatment has the potential to increase the total ethanol production capacity of kitchen waste and is beneficial to the formation of a more economically feasible process for the bioethanol production from kitchen waste

Effect of Temperature on a Lignin-based Polymer with Two Types of Microstructures

A lignin-based polymer (GCL1-JB) was dispersed in solvents with different proportion between 1,4 dioxane and water for forming linear and spherical microstructures. The effects of temperature on the solution behaviors and adsorption characteristics of GCL1-JB with different microstructures were investigated by light scattering, conductivity, zeta potential, UV-Vis spectroscopy, atomic force microscopy (AFM), and contact angle measurements. Results showed that GCL1-JB solutions with different microstructures have different responses to environmental temperature changes, which is related to the movements of charges. For GCL1-JB with a spherical microstructure, as the temperature increases, the degree of ionization does not decrease. However, the surface charges decrease due to the charged groups moving from the surface into the interior because of the charge gradient, which induces a significant decrease in the zeta potential. As the surface charges decrease and the hydrophobic interaction increases, the GCL1-JB aggregates. Therefore, the scattered light intensity increases significantly and the corresponding GCL1-JB adsorbed film has a larger adsorbed amount, a more rough surface, and a larger contact angle. However, for GCL1-JB with a linear microstructure, the surface charges do not obviously change with a temperature increase, even though the charged groups move from side to side. Therefore, the zeta potential and the scattered light intensities of these GCL1-JB solutions are basically independent of temperature, and the corresponding adsorption characteristics do not obviously change

Moderate/Severe hyponatremia increases the risk of death among hospitalized Chinese human immunodeficiency virus/acquired immunodeficiency syndrome patients.

OBJECTIVES: To evaluate whether the serum sodium concentration is associated with the progression and long-term prognosis of Chinese HIV/AIDS patients. METHODS: Three hundred and eighty seven hospitalized patients were recruited into this retrospective cohort study. The strata of serum sodium concentration were moderate/severe hyponatremia, mild hyponatremia and normonatremia. Disease progression was estimated using CD4 counts and the WHO clinical stage. Correlation analysis was used to evaluate the serum sodium concentration with disease progression. The Kaplan-Meier method and the Cox proportional hazards model were used to analyze the effect of different serum sodium levels on survival. RESULTS: In this study 206 patients (53.2%) had hyponatremia, including 10.6% patients with moderate/severe hyponatremia and 42.6% with mild hyponatremia. The serum sodium concentration was significantly correlated with the HIV/AIDS progression (P<0.001). During the follow-up, 100 patients (25.6%) died. The cumulative survival rates of HIV/AIDS patients were 47.8% ± 8.5% in patients with moderate/severe hyponatremia, 59.8% ± 5.0% with mild hyponatremia and 79.9% ± 3.4% with normonatremia (log-rank P<0.001). After adjusting for sex, age, WHO stage, CD4 count, hemoglobin and albumin, the relative hazard was 3.5 (95% CI: 1.9-6.5) for patients with moderate/severe hyponatremia (P<0.001), and 1.5 (95% CI: 0.9-2.4) for those with mild hyponatremia (P = 0.161), compared with normonatremic patients. CONCLUSIONS: The serum sodium level is closely correlated with the severity of patients. Only moderate/severe hyponatremia affects the prognosis of Chinese HIV/AIDS patients. Earlier intensive medical managements(including HAART)are necessary to increase the survival rates of Chinese HIV/AIDS patients with moderate/severe hyponatremia

Longitudinal Relationship between Bullying Victimization and Non-Suicidal Self-Injury among Chinese Adolescents: The Buffering Roles of Gratitude and Parental Autonomy Support

Drawing on the resilience-oriented socioecological framework, the current study contributes to scarce scholarship by exploring intrapersonal (i.e., gratitude) and interpersonal (i.e., parental autonomy support) factors in the longitudinal association between bullying victimization and adolescent non-suicidal self-injury (NSSI). Participants were 238 Chinese adolescents (Mage at Time 1 (T1) = 13.45 years; 106 girls and 132 boys) based on a two-wave prospective design with data spanning one year. At T1, adolescents self-rated all study variables, and at Time 2 (T2), youth again reported their NSSI. The results showed a significant main effect (b = 0.12, SE = 0.05, p = 0.04), indicating that bullying victimization was positively related to T2 NSSI one year later, even controlling for T1 NSSI. Moderation analyses further indicated that parental autonomy support buffered against the positive association between bullying victimization and T2 NSSI, but only when adolescents experienced lower levels of gratitude. Specifically, for adolescents with lower levels of gratitude, high levels of parental autonomy support, in a compensatory way, prevented adolescents from NSSI after victimization occurred (b = −0.03, SE = 0.09, p = 0.78); by contrast, for those with higher levels of gratitude, bullying victimization was not significantly related to T2 NSSI, regardless of the levels of parental autonomy support (b = 0.07, SE = 0.04, p = 0.59 for higher parental autonomy support; b = 0.01, SE = 0.07, p = 0.93 for lower parental autonomy support). These findings suggest that gratitude and parental autonomy support, manifesting in a compensatory interaction pattern, could serve as targeted agents for breaking the vicious linkage between bullying victimization and NSSI