Evaluation of Anti-Inflammatory Activities of Qingre-Qushi Recipe (QRQS) against Atopic Dermatitis: Potential Mechanism of Inhibition of IL-33/ST2 Signal Transduction

To evaluate the anti-inflammatory activities of QRQS against AD and the inhibitory molecular mechanisms of IL-33/ST2 signal transduction, BALB/c mice were divided into six groups (normal control, OVA control, low-dose of QRQS, middle-dose of QRQS, high-dose of QRQS, and cetirizine) and epicutaneously exposed to ovalbumin or PBS for 3 weeks and treated with QRQS for 2 weeks. Skin biopsies and blood samples were obtained for histological study, antibody analysis, and RNA isolation. HaCaT cells, stimulated by TNF-α and IFN-γ, were treated with QRQS to evaluate mRNA and protein expression by RT-PCR and ELISA. QRQS decreased both epidermal and dermal thickness, alleviated dermatitis, and reduced IL-33 and ST2 positive cell numbers. The concentration of specific IgE, IgG, IgG1, and IgG2a antibodies in serum and the expression of IL-33, ST2, IL-1RAcP, IL-4, and IL-13 mRNA in the skin were suppressed. No significant difference exists in TNF-α or IFN-γ. QRQS decreased IL-33 mRNA and protein secretion in HaCaT cells exposed to TNF-α and IFN-γ in a time- and concentration-dependent manner. QRQS regulates related molecule expression of ovalbumin-induced dermatitis involved in the IL-33/ST2 signaling axis in the treatment of acute AD

Sintering Temperature Induced Evolution of Microstructures and Enhanced Electrochemical Performances: Sol-Gel Derived LiFe(MoO4)2 Microcrystals as a Promising Anode Material for Lithium-Ion Batteries

A facile sol-gel process was used for synthesis of LiFe(MoO4)2 microcrystals. The effects of sintering temperature on the microstructures and electrochemical performances of the as-synthesized samples were systematically investigated through XRD, SEM and electrochemical performance characterization. When sintered at 650°C, the obtained LiFe(MoO4)2 microcrystals show regular shape and uniform size distribution with mean size of 1–2 μm. At the lower temperature (600°C), the obtained LiFe(MoO4)2 microcrystals possess relative inferior crystallinity, irregular morphology and vague grain boundary. At the higher temperatures (680 and 700°C), the obtained LiFe(MoO4)2 microcrystals are larger and thicker particles. The electrochemical results demonstrate that the optimized LiFe(MoO4)2 microcrystals (650°C) can deliver a high discharge specific capacity of 925 mAh g−1 even at a current rate of 1 C (1,050 mA g−1) after 500 cycles. Our work can provide a good guidance for the controllable synthesis of other transition metal NASICON-type electrode materials

High-loading food waste and blackwater anaerobic co-digestion: Maximizing bioenergy recovery

In this study, food waste (FW) was added into source-diverted blackwater (BW) to enhance biomethane production using an upflow anaerobic sludge blanket (UASB) reactor at 35 °C. Increasing amount of FW was introduced into the BW according to the BW:FW volatile solids (VS) mixing ratios ranging from 1:0.3 (BW:FW) to 1:1.5. The optimal biomethane recovery efficiency was achieved when BW:FW VS mixing ratio was 1:1, corresponding to an organic loading rate (OLR) of 10.0 (±0.5) kg chemical oxygen demand (COD)/m3/day, which is 2.5 times of the highest OLR reported in the literature for BW treatment (4.1 kg COD/m3/day). Under this condition, a methane production rate of 2.42 (±0.15) L/L/day (highest biomethane recovery efficiency for BW treatment studies reported to date) was achieved, which represented 96.8 MJ/m3/day heat recovery. The enhanced biomethane production was attributed to the significantly improved solid substrate hydrolysis efficiency (85.9% higher than BW only) and microbial activities (sludge hydrogenotrophic methanogenic activities 2.4 times higher than BW only). Further OLR increase with more FW addition led to a reduction in methane production due to insufficient sludge retention. It can be concluded that anaerobic co-digestion of BW and FW is an attractive approach to maximize biomethane recovery efficiency from domestic wastewater in future decentralized wastewater treatment facilities.</p

Mature landfill leachate treatment using granular sludge-based reactor (GSR) via nitritation/denitritation: Process startup and optimization

Mature landfill leachate wastewater (LLW) was characterized by high ammonia, refractory chemical oxygen demand (COD) and heavy metal contents, which limits the nitrogen removal in conventional activated sludge systems. Granular sludge is known to be more resistant to toxic compounds because of its dense structure and diverse microbial community. Here, granular sludge-based reactor (GSR) was applied with nitritation/denitritation (Nit/DNit) process for effective ammonia-rich mature LLW treatment at 20 °C. After a short startup period, the efficiencies of ammonia removal and total inorganic nitrogen removal stabilized at 99 % and 93 %, respectively, under a hydraulic retention time (HRT) of 6 h. High ammonia oxidation rate (~ 0.64 g N/g VSS/d) was achieved, with ~93 % ammonia conversing to nitrite before being reduced to nitrogen gas. Microbial analysis results revealed that Nitrosomonas (ammonia oxidizing bacteria) and Thauera (denitrifiers) were the dominant bacteria with key functional genes involved in the Nit/DNit. With an increase in the LLW loading, increased ammonia oxidation rates and biomass retention were also observed. This study demonstrated that granular sludge-based technology is feasible for mature LLW treatment.</p

Compounding self-excited and hidden attractors via a non-autonomous approach

Compounding attractors, as an effective way to enhance the complexity of existing chaotic attractors, has attracted high attention. Various autonomous approaches have been devised to compound some self-excited attractors, but few involve non-autonomous approaches. Meanwhile, a universal and uncomplicated approach is still lacking. Focusing on non-autonomous domains, we propose a pulse control approach in this paper, which is directly applied to the constant terms of some known chaotic system equations to generate different types of compound self-excited and hidden attractors. Then, by setting the proper pulse signal functions we designed in this transformation, the number, shape, and size of these novel compound attractors are all controllable. The dynamical behaviors are theoretically analyzed, such as Lyapunov exponent spectra, bifurcation diagrams and so on. Furthermore, the corresponding hardware implementation by Field Programmable Gate Array (FPGA) is given. The hardware experimental results are consistent with the numerical simulations

Responses of various carbon to nitrogen ratios to microbial communities, kinetics, and nitrogen metabolic pathways in aerobic granular sludge reactor

The role of different ammonia concentrations (mg N/L) (of 100 (carbon to nitrogen ratio (C/N) = 12; Stage I), 200 (C/N = 6; Stage II), 400 (C/N = 3; Stage III) and 200 (C/N = 6; Stage IV)) in nitrogen metabolic pathways, microbial community, and specific microbial activity were investigated in an aerobic granular sludge reactor. Heterotrophic ammonia oxidizing bacteria (HAOB) showed higher ammonia oxidation rates (AORs) than autotrophic ammonia oxidizing bacteria (AAOB) at higher C/N conditions (Stages I and II). Paracoccus was the dominant HAOB. AAOB, with only 0.2–0.3 % in relative abundance, showed 2.7-fold higher AORs than HAOB at elevated ammonia and free ammonia (FA) concentrations with C/N at 3. Nitrosomonas and a genus in Nitrosomondaceae family were the major AAOB. This study proposed that FA inhibition on heterotrophic bacteria might be the mechanism that contributes to the development of the autotrophic ammonia oxidation pathway and enrichment of AAOB.</p

Modeling and optimization of an upflow anaerobic sludge blanket (UASB) system treating blackwaters

In the present work, a novel mathematical dynamic model describing the upflow anaerobic sludge blanket (UASB) has been developed. The model incorporates both the biological processes and the transport of sludge particles specifically related to the UASB treatment of blackwater. The processes occurring in the reactor are modeled as a sequence of two completely-mixed reactive tanks, one representing the sludge bed where most solids concentrate and the other representing a less solid-concentrated liquid volume. Solids from the sludge bed are assumed to be dragged to the upper zone of the reactor by the methane gas produced. The time variation of the sludge bed volume is included by assuming a constant sludge density. The model is calibrated against published data obtained from a stable operation of a lab-scale UASB system treating at different organic loading rates blackwater collected from real vacuum toilets. Good model prediction compatibility with the measurements of emitted biogas and methane gas flow rates, effluent COD, volatile fatty acids, pH and sludge bed volume was revealed. Furthermore, the model was successfully validated against another independent set of data from a UASB reactor treating a more diluted type of blackwater collected from conventional toilets. A scenario analysis performed using such a validated model reveals higher methane production yield but also higher effluent COD concentration at increasing organic loading rates and sludge bed volumes. It is found that longer HRTs can improve COD removal efficiency and methane production in blackwater treatment processes.</p

Role of syntrophic acetate oxidation and hydrogenotrophic methanogenesis in co-digestion of blackwater with food waste

Blackwater collected from toilets represents a type of sustainable bioenergy resource in the modern sanitation system, while its biomethane recovery efficiencies through anaerobic digestion were limited by slow hydrolysis and inhibited methanogenesis due to a large fraction of solid organics and high free ammonia concentrations. In the current study, food waste and blackwater co-digestion was performed in an up-flow anaerobic sludge blanket (UASB) reactor (35 °C). Co-substrates with increasing food waste proportions were stepwise applied to demonstrate the threshold organic loading rate (OLR). Co-digestion effectively enhanced substrate hydrolysis efficiency by up to 86.1% and methanisation rate by up to 39.7% compared to blackwater mono-digestion. Hydrogenotrophic methanogens showed predominance in both feeding conditions. The dominant bacterial groups shifted from genus Bacteroides to T78, and methanogenic groups shifted from genus Methanogenium to Methanoculleus and Methanospirillum when the operation system shifted from blackwater mono-digestion to food waste co-digestion. The microbial community structures and the isotopic carbon analysis for CH4 and CO2 in the produced biogas indicated that a combined syntrophic acetate oxidation (SAO) and hydrogenotrophic methanogenesis (HM) pathway was established throughout the operation. The enhanced substrates’ properties including higher carbon/nitrogen (C/N) ratios and more readily biodegradable organics in food waste and blackwater co-digestion system contributed to the enhancements in biomethane recovery and microbial development compared to blackwater mono-digestion. The OLR stress under the overloaded condition negatively affected the microbial community structure and resulted in process deterioration

Performance of anaerobic treatment of blackwater collected from different toilet flushing systems: Can we achieve both energy recovery and water conservation?

Source-diverted blackwater (toilet wastewater) contains most of the organic energy in domestic wastewater and can be treated anaerobically to maximize energy recovery. Blackwater collected from toilets of different water saving options (e.g., conventional, dual and vacuum toilets) represents different characteristics, but their digestibility has not been discussed. In the present study, blackwater collected from different toilet flushing systems were characterized and compared in terms of chemical composition, digestibility and microbial population development during biochemical methane potential (BMP) tests. Interestingly, the highest BMP (48%) was achieved for conventional/dual flush toilet (5–9 L water/flush) blackwaters, whereas vacuum toilet (0.5–1.2 L water/flush) blackwater BMP was only 34%. Elevated free ammonia (FA) concentration (>205 mg L−1) appeared to contribute to the reduced digestibility of high-water saving toilet (< 1.5 L water/flush) blackwaters. Methanogenesis was the major FA inhibition step in anaerobic digestion as evident by batch kinetics studies; where Methanosarcina methanogens predominate in all blackwater, but ammonia-tolerance methanogens Methanoculleus and Methanomicrobiales were also predominant in blackwater collected from vacuum toilets. This work underlines that overall measures of sustainability also need to consider blackwater characteristics when designing resource recovery based source-diverted sanitary treatment systems.</p