Design, Synthesis and Antifungal Activities of Novel Pyrazole Analogues Containing the Aryl Trifluoromethoxy Group.

On the basis of the three-component synthetic methodology developed by us, a total of twenty-six pyrazole compounds bearing aryl OCF3 were designed and synthesized. Their chemical structures were characterized by 1H and 13C nuclear magnetic resonance and high-resolution mass spectrometry. These compounds were evaluated systematically for antifungal activities in vitro against six plant pathogenic fungi by the mycelium growth rate method. Most of the compounds showed some activity against each of the fungi at 100 µg/mL. Compounds 1t and 1v exhibited higher activity against all the tested fungi, and 1v displayed the highest activity against F. graminearum with an EC50 value of 0.0530 µM, which was comparable with commercial pyraclostrobin. Structure-activity relationship analysis showed that, with respect to the R1 substituent, the straight chain or cycloalkyl ring moiety was a key structural moiety for the activity, and the R2 substituent on the pyrazole ring could have significant effects on the activity. Simple and readily available pyrazoles with potent antifungal activity were obtained, which are ready for further elaboration to serve as a pharmacophore in new potential antifungal agents.

The D129L protein of African swine fever virus interferes with the binding of transcriptional coactivator p300 and IRF3 to prevent beta interferon induction.

IMPORTANCE: African swine fever (ASF) is an acute, hemorrhagic, and severe porcine infectious disease caused by African swine fever virus (ASFV). ASF outbreaks severely threaten the global pig industries and result in serious economic losses. No safe and efficacious commercial vaccine is currently available except in Vietnam. To date, large gaps in the knowledge concerning viral biological characteristics and immunoevasion strategies have hindered the ASF vaccine design. In this study, we demonstrate that pD129L negatively regulates the type I interferon (IFN) signaling pathway by interfering with the interaction of the transcriptional coactivator p300 and IRF3, thereby inhibiting the induction of type I IFNs. This study reveals a novel immunoevasion strategy employed by ASFV, shedding new light on the intricate mechanisms for ASFV to evade the host immune responses.

The E301R protein of African swine fever virus functions as a sliding clamp involved in viral genome replication.

IMPORTANCE: Sliding clamp is a highly conserved protein in the evolution of prokaryotic and eukaryotic cells. The sliding clamp is required for genomic replication as a critical co-factor of DNA polymerases. However, the sliding clamp analogs in viruses remain largely unknown. We found that the ASFV E301R protein (pE301R) exhibited a sliding clamp-like structure and similar functions during ASFV replication. Interestingly, pE301R is assembled into a unique ring-shaped homotetramer distinct from sliding clamps or proliferating cell nuclear antigens (PCNAs) from other species. Notably, the E301R gene is required for viral life cycle, but the pE301R function can be partially restored by the porcine PCNA. This study not only highlights the functional role of the ASFV pE301R as a viral sliding clamp analog, but also facilitates the dissection of the complex replication mechanism of ASFV, which provides novel clues for developing antivirals against ASF.

The effect of electroacupuncture at ST25 on Parkinson's disease constipation through regulation of autophagy in the enteric nervous system.

The effectiveness and safety of electroacupuncture (EA) for constipation have been confirmed by numerous clinical studies and experiments, and there are also studies on the efficacy of EA for Parkinson's disease (PD) motor symptoms. However, there are few researches on EA for PD constipation. Autophagy is thought to be involved in the mechanistic process of EA in the central nervous system (CNS) intervention in Parkinson's pathology. However, whether it has the same effect on the enteric nervous system (ENS) has not been elucidated. Therefore, we investigated whether EA at Tianshu (ST25) acupoint promotes the clearance of α-Syn and damaged mitochondria aggregated in the ENS in a model of rotenone-induced PD constipation. This study evaluated constipation symptoms by stool characteristics, excretion volume, and water content, and the expression levels of colonic ATG5, LC3II, and Parkin were detected by Western Blot (WB) and Real-Time Quantitative PCR (RT-qPCR). The relationship between the location of α-Syn and Parkin in the colonic ENS was observed by immunofluorescence (IF). The results showed that EA intervention significantly relieved the symptoms of rotenone-induced constipation in PD rats, reversed the rotenone-induced down-regulation of colonic ATG5, LC3II, and Parkin expression, and the positional relationship between colonic α-Syn and Parkin proved to be highly correlated. It is suggested that EA might be helpful in treating PD constipation by modulating Parkin-induced mitochondrial autophagy.

DeepTag: A General Framework for Fiducial Marker Design and Detection.

A fiducial marker system usually consists of markers, a detection algorithm, and a coding system. The appearance of markers and the detection robustness are generally limited by the existing detection algorithms, which are hand-crafted with traditional low-level image processing techniques. Furthermore, a sophisticatedly designed coding system is required to overcome the shortcomings of both markers and detection algorithms. To improve the flexibility and robustness in various applications, we propose a general deep learning based framework, DeepTag, for fiducial marker design and detection. DeepTag not only supports detection of a wide variety of existing marker families, but also makes it possible to design new marker families with customized local patterns. Moreover, we propose an effective procedure to synthesize training data on the fly without manual annotations. Thus, DeepTag can easily adapt to existing and newly-designed marker families. To validate DeepTag and existing methods, beside existing datasets, we further collect a new large and challenging dataset where markers are placed in different view distances and angles. Experiments show that DeepTag well supports different marker families and greatly outperforms the existing methods in terms of both detection robustness and pose accuracy. Both code and dataset are available at https://herohuyongtao.github.io/research/publications/deep-tag/.

New Insights into the Crosstalk among the Interferon and Inflammatory Signaling Pathways in Response to Viral Infections: Defense or Homeostasis.

Innate immunity plays critical roles in eliminating viral infections, healing an injury, and restoring tissue homeostasis. The signaling pathways of innate immunity, including interferons (IFNs), nuclear factor kappa B (NF-κB), and inflammasome responses, are activated upon viral infections. Crosstalk and interplay among signaling pathways are involved in the complex regulation of antiviral activity and homeostasis. To date, accumulating evidence has demonstrated that NF-κB or inflammasome signaling exhibits regulatory effects on IFN signaling. In addition, several adaptors participate in the crosstalk between IFNs and the inflammatory response. Furthermore, the key adaptors in innate immune signaling pathways or the downstream cytokines can modulate the activation of other signaling pathways, leading to excessive inflammatory responses or insufficient antiviral effects, which further results in tissue injury. This review focuses on the crosstalk between IFN and inflammatory signaling to regulate defense and homeostasis. A deeper understanding of the functional aspects of the crosstalk of innate immunity facilitates the development of targeted treatments for imbalanced homeostasis.

The H240R Protein of African Swine Fever Virus Inhibits Interleukin 1ß Production by Inhibiting NEMO Expression and NLRP3 Oligomerization.

The H240R protein (pH240R), encoded by the H240R gene of African swine fever virus (ASFV), is a 241-amino-acid capsid protein. We previously showed that the deletion of H240R from the ASFV genome, creating ASFV-ΔH240R, resulted in an approximately 2-log decrease in infectious virus production compared with the wild-type ASFV strain (ASFV-WT), and ASFV-ΔH240R induced higher interleukin 1ß (IL-1ß) production in porcine alveolar macrophages (PAMs) than did ASFV-WT, but the underlying mechanism remains to be elucidated. Here, we demonstrate that the activation of the NF-κB signaling and NLRP3 inflammasome was markedly induced in PAMs upon ASFV-ΔH240R infection compared with ASFV-WT. Moreover, pH240R inhibited NF-κB activation by interacting with NEMO and promoting the autophagy-mediated lysosomal degradation of NEMO, resulting in reduced pro-IL-1ß transcription. Strikingly, NLRP3 deficiency in PAMs inhibited the ASFV-ΔH240R-induced IL-1ß secretion and caspase 1 activation, indicating an essential role of NLRP3 inflammasome activation during ASFV-ΔH240R replication. Mechanistically, pH240R interacted with NLRP3 to inhibit its oligomerization, leading to decreased IL-1ß production. Furthermore, the inhibition of the NF-κB signaling and NLRP3 inflammasome activation promoted ASFV-ΔH240R replication in PAMs. Taken together, the results of this study reveal an antagonistic mechanism by which pH240R suppresses the host immune response by manipulating activation of the NF-κB signaling and NLRP3 inflammasome, which might guide the rational design of live attenuated vaccines or therapeutic strategies against ASF in the future. IMPORTANCE African swine fever (ASF), a lethal hemorrhagic disease, is caused by African swine fever virus (ASFV). There are no commercially available vaccines or antivirals for the disease. Here, we showed that ASFV with a deletion of the H240R gene exhibits high-level expression of interleukin 1ß (IL-1ß), a proinflammatory cytokine, in porcine alveolar macrophages and that the H240R protein (pH240R) exhibits robust inhibitory effects on IL-1ß transcription and production. More specifically, pH240R inhibited NF-κB activation via the autophagy-mediated lysosomal degradation of NEMO, leading to the decrease of pro-IL-1ß transcription. In addition, pH240R interacted with NLRP3 to inhibit its oligomerization, leading to decreased IL-1ß production. Our results indicate that pH240R is involved in the evasion of host innate immunity and provide a novel target for the development of a live attenuated vaccine against ASF.

Antibody-Dependent Enhancement: ″Evil″ Antibodies Favorable for Viral Infections.

The pandemics caused by emerging viruses such as severe acute respiratory syndrome coronavirus 2 result in severe disruptions to public health. Vaccines and antibody drugs play essential roles in the control and prevention of emerging infectious diseases. However, in contrast with the neutralizing antibodies (NAbs), sub- or non-NAbs may facilitate the virus to enter the cells and enhance viral infection, which is termed antibody-dependent enhancement (ADE). The ADE of most virus infections is mediated by the Fc receptors (FcRs) expressed on the myeloid cells, while others are developed by other mechanisms, such as complement receptor-mediated ADE. In this review, we comprehensively analyzed the characteristics of the viruses inducing FcRs-mediated ADE and the new molecular mechanisms of ADE involved in the virus entry, immune response, and transcription modulation, which will provide insights into viral pathogenicity and the development of safer vaccines and effective antibody drugs against the emerging viruses inducing ADE.

Parkinson's disease constipation effect of electroacupuncture at ST25 through colonic motility and enteric neuropathology.

Background: The enteric nervous system (ENS) plays a central role in developing Parkinson's disease (PD) constipation, and the regulation of the ENS may be a key component in treating PD constipation. Electroacupuncture (EA) can effectively treat constipation symptoms in PD, but research on its specific mechanisms, especially in terms of ENS, is relatively lacking. Therefore, we investigated whether EA at ST25 promotes the restoration of ENS structure and colonic motor function in the rotenone-induced PD constipation rat model. Methods: In this study, we evaluated constipation symptoms by stool characteristics, excretion and water volume, and whole gut transit time and observed colonic motility regulation through colonic motion detection and pathological changes in the colonic myenteric nervous plexus by transmission electron microscopy and immunofluorescence staining. Results: EA significantly improved the constipation symptoms and positively adjusted the colonic motility in rotenone-induced PD constipation rats. At the same time, EA reversed the rotenone-induced colonic myenteric nervous plexus injury and regulated the ratio of inhibitory and excitatory neurotransmitters. Conclusion: Our results indicate that EA treatment of PD constipation may be mediated through the adjustment of ENS.

TopoTag: A Robust and Scalable Topological Fiducial Marker System.

Fiducial markers have been playing an important role in augmented reality (AR), robot navigation, and general applications where the relative pose between a camera and an object is required. Here we introduce TopoTag, a robust and scalable topological fiducial marker system, which supports reliable and accurate pose estimation from a single image. TopoTag uses topological and geometrical information in marker detection to achieve higher robustness. Topological information is extensively used for 2D marker detection, and further corresponding geometrical information for ID decoding. Robust 3D pose estimation is achieved by taking advantage of all TopoTag vertices. Without sacrificing bits for higher recall and precision like previous systems, TopoTag can use full bits for ID encoding. TopoTag supports tens of thousands unique IDs and easily extends to millions of unique tags resulting in massive scalability. We collected a large test dataset including in total 169,713 images for evaluation, involving in-plane and out-of-plane rotation, image blur, different distances, and various backgrounds, etc. Experiments on the dataset and real indoor and outdoor scene tests with a rolling shutter camera both show that TopoTag significantly outperforms previous fiducial marker systems in terms of various metrics, including detection accuracy, vertex jitter, pose jitter and accuracy, etc. In addition, TopoTag supports occlusion as long as the main tag topological structure is maintained and allows for flexible shape design where users can customize internal and external marker shapes. Code for our marker design/generation, marker detection, and dataset are available at http://herohuyongtao.github.io/research/publications/topo-tag/.

CD73 regulates hepatic stellate cells activation and proliferation through Wnt/ß-catenin signaling pathway.

Alcoholic liver fibrosis (ALF) is commonly associated with long-term alcohol consumption and the activation of hepatic stellate cells (HSCs). Inhibiting the activation and proliferation of HSCs is a critical step to alleviate liver fibrosis. Increasing evidence indicates that ecto-5'-nucleotidase (CD73) plays a vital role in liver disease as a critical component of extracellular adenosine pathway. However, the regulatory role of CD73 in ALF has not been elucidated. In this study, both ethanol plus CCl4-induced liver fibrosis mice model and acetaldehyde-activated HSC-T6 cell model were employed and the expression of CD73 was consistently elevated in vivo and in vitro. C57BL/6 J mice were intraperitoneally injected with CD73 inhibitor Adenosine 5'-(α, ß-methylene) diphosphate sodium salt (APCP) from 5th week to the 8th week in the development of ALF. The results showed APCP could inhibit the activation of HSCs, reduce fibrogenesis marker expression and thus alleviate ALF. Silencing of CD73 inhibited the activation of HSC-T6 cells and promoted apoptosis of activated HSC-T6 cells. What's more, the proliferation of HSC-T6 cells was inhibited, which was characterized by decreased cell viability and cycle arrest. Mechanistically, Wnt/ß-catenin pathway was activated in acetaldehyde-activated HSC-T6 cells and CD73 silencing or overexpression could regulate Wnt/ß-catenin signaling pathway. Collectively, our study unveils the role of CD73 in HSCs activation, and Wnt/ß-catenin signaling pathway might be involved in this progression.

Diagnostic efficacy of 2-shot compressed sensing cine sequence cardiovascular magnetic resonance imaging for left ventricular function.

BACKGROUND: Cardiac magnetic resonance cine images are conventionally acquired in breath-hold with a segmented balanced steady-state free precession (bSSFP) sequence, which requires a relatively long acquisition time and high patient cooperation. The single-shot compressed sensing (ss CS) cine sequence is a real-time sequence that has reasonable spatial and temporal resolution and can be applied during free breathing. However, the contrast between the myocardium and surrounding soft tissue is relatively reduced, and the epicardial delineation results are not as accurate with the ss CS cine sequence compared with the bSSFP sequence. In this study, we evaluated the use of a 2-shot CS cine technique in quickly acquiring high-quality images and accurately assessing cardiac function in clinical practice. METHODS: The patients enrolled in the study underwent cardiovascular magnetic resonance (CMR) on a 3T scanner from Jul. to Dec. 2018. Cine imaging was performed with 3 different methods: a standard segment cine sequence, a real-time ss CS cine sequence, and a 2-shot CS cine sequence prototype. Quantitative analysis of image quality was performed using a 0-4 scoring system, and also edge sharpness was measured, and cardiac function analysis was performed for all 3 types of cine images. RESULTS: Thirty-eight patients underwent imaging with the three types of cine sequences. The average scan time of the standard cine sequence was 101±20 s, the average scan time of the ss CS cine sequence was 20±4 s, and the average scan time of the 2-shot CS cine sequence was 30±6 s. The standard cine sequence image score was 3.68±0.64 and edge sharpness was (2.47±0.18) mm, the ss CS cine sequence image score was 3.13±0.35 and edge sharpness was (4.69±0.02) mm, and the 2-shot cine sequence image score was 3.54±0.51 and the edge sharpness was (2.51±0.13) mm. In terms of the quantitative study of cardiac function, the differences between the standard cine sequence and the ss CS cine sequence were not statistically significant, except for those of the imaging score and LV mass. There were no significant differences in the cardiac function parameters between the standard cine sequence and the 2-shot cine sequence. There was a strong correlation between the standard cine and ss CS cine sequences and between the standard cine and 2-shot CS cine sequences (P<0.01) of all the cardiac function parameters. CONCLUSIONS: The 2-shot CS cine sequence can acquire images with a level of quality comparable to that of the standard cine sequence in a significantly shorter period of time. The functional parameters are similar between the 2-shot CS cine sequence and the standard cine sequence.

Effects of zinc oxide nanoparticles on sludge anaerobic fermentation: phenomenon and mechanism.

Zinc oxide nanoparticles (ZnO NPs) production and usage might lead to a large discharge of ZnO NPs into the natural environment, raising concerns of pollution and ecological security. The effects of ZnO NPs on waste activated sludge hydrolytic acidification and microbial communities were studied in semi-continuous fermentation systems. The fermentation performance of eight ZnO NPs concentrations including ZnO NPs normal [0.01, 0.1, 1 and 10 mg/g mixed liquor suspended solids (MLSS)] and ZnO NPs shock (10, 1000, 1000 and 10,000 mg/g MLSS) were discussed, and their biodegradability was also analyzed. The experimental results showed that proteins, polysaccharides and short-chain fatty acids were enhanced by ZnO NPs, particularly by ZnO NPs shock. Low ZnO NPs concentrations inhibited coenzyme 420 (F420) and dehydrogenase activities but enhanced α-glucosidase and protease activities. Illumina MiSeq sequencing revealed that ZnO NPs addition enriched Azospira, Ottowia and Hyphomicrobium but not Anaerolineaceae.

[Feasibility of Non-contrast-enhanced Coronary Magnetic Resonance Angiography at 3.0T].

Objective To evaluate the feasibility of non-contrast-enhanced magnetic resonance angiography (NCE-MRA) on a 3.0T scanner. Methods Totally 36 volunteers and 24 patients with clinically suspected coronary artery disease underwent NCE-MRA. The quality of the NCE-MRA images was graded for each segment on a four-point scale. The subjects were divided into two groups according to image quality. The age,body mass index (BMI),heart rate,end-expiratory diaphragm displacement,and respiratory diaphragm motion amplitude were evaluated and compared. Results The average image quality score of every segment was above 2 points. The proximal and middle segments of left anterior descending artery had significantly higher quality scores than the distal segments (P=0.000) and the proximal segment of left circumflex coronary artery had significantly higher quality scores than the distal segments (P=0.000),the proximal segment of right coronary artery also had a significant higher quality score than its distal segment (P=0.001). The image quality was good in 38 subjects (64.4%). The heart rate [(66.35±9.39) beat/min vs. (75.32±11.67) beat/min] (P=0.002) and the body mass index [(24.72±3.33) kg/m 2 vs. (27.82±3.61) kg/m 2] (P=0.002) were significantly different between the good image quality group and the poor image quality group. The end-expiratory diaphragm displacement in good image quality group was (4.43±2.07)mm,which was significantly lower than that in poor image quality group [(9.26±7.62)mm](P=0.013). The respiratory diaphragm motion amplitude [(21.35±6.02) mm] in good image quality group was significantly lower than that in poor image quality group [(30.68±14.20)mm](P=0.012). Conclusion NCE-MRA on 3.0T is a feasible tool for visualization of the proximal and middle segments of coronary arteries,and the image quality can be optimized by controlling heart rate and respiration in the future.

Bio-inspired fabrication of Ester-functionalized imprinted composite membrane for rapid and high-efficient recovery of lithium ion from seawater.

Lithium ion (Li+) is one of the important sustainable resource and it's urgently demanded to develop high-selectivity and high-efficient method to extract of Li+ from seawater. Hence, we propose the ester-functionalized ion-imprinted membrane (IIMs) with high selectivity and stability for the rebinding and separation of Li+ in aqueous medium via ion imprinted technology and membrane separation technology. In this work, the hydrophilic polydimethylsiloxane membranes (PDMS) are synthesized by self-polymerization of dopamine (DA) in aqueous solution, resulting in the fabrication of dense poly-dopamine (PDA) layer on the surface of PDMS (PDMS-PDA). In view of weak bonding forces (such as hydrogen bond, ionic bond and Van der Waals' force) between traditional imprinted polymer and ligand, the ester groups are formed between modified PDMS-PDA and ligand by surface grafting. The obtained Li+ imprinted membranes (Li-IIMs) have a suitable cavity and high adsorption capacity toward Li+ which reveal a high rebinding capacity (50.872 mg g-1) toward Li+ based on ample rebinding sites and strong affinity force. The superior relative selectivity coefficients (αNa/Li, αK/Li and αRb/Li are 1.71, 4.56 and 3.80, respectively) can be also achieved. The selectivity factors of Li-IIMs for Na+, K+ and Rb+ are estimated to be 2.52, 2.8 and 3.03 times larger than Li+ non-imprinted membranes (Li-NIMs), which imply the superior selectivity of Li-IIMs toward Li+. The regeneration ability of Li-IIMs is observed by systematic batch experiments. In summary, it can be concluded that the rebinding capacities of Li-IIMs is slightly decrease after eluting process, owing to the Li-IIMs with outstanding stability performance. Presentation of the method pave a fine prospect for coming true the long-term use of imprinted membrane.

Response of extracellular polymeric substances and enzymatic activity to salinity for the waste activated sludge anaerobic fermentation process.

Salinity (NaCl) was used in waste activated sludge (WAS) anaerobic fermentation system which had been presented to greatly enhance the extracellular polymeric substance (EPS) production including protein and polysaccharide and short-chain fatty acids (SCFAs). Salinity enhanced soluble protein and polysaccharide (SB-EPS) release which was 4.04 times (protein) and 1.83 times (polysaccharide) compared to 0 g/L NaCl level. More important, salinity restrained the coenzyme 420 activity (F420), but increased the hydrolase activity. Abundant hydrolysis of substrate and highly active hydrolase led to abundant SCFA production. Pearson correlation coefficient showed that the protein became the main reaction substrate for SCFA generation.

Regulation of CD39 expression in ATP-P2Y2R-mediated alcoholic liver steatosis and inflammation.

Inflammation plays a central role in the progression of alcoholic liver disease. ATP-P2Y2R signaling and CD39 play an important role in various diseases, but little is known about their role in alcoholic liver steatosis and inflammation. As a transmembrane hydrolase, CD39 hydrolyzes ATP, while the mutual regulation of CD39 and ATP-P2Y2R in alcoholic steatohepatitis is poorly understood. Here, we found that the expression of ATP, P2Y2R, and CD39 is increased significantly both in the liver of alcohol-fed mice and alcohol-induced RAW264.7 cell lines. In this study, C57BL/6 mice were intrapretationally injected with P2Y2R inhibitor suramin from day 4 until day 10 during the induction of a chronic/binge drinking model. Pharmacological blockade of P2Y2R largely prevents liver damage, lipid accumulation, and inflammation, with concomitant down-expression of CD39 in liver. We found that the inhibition of P2Y2R in vitro reduces inflammation via down-expression of interleukin 6 (IL-6), interleukin-1ß (IL-1ß), and tumor necrosis factor-alpha (TNF-α), and the expression of CD39 was reduced, whereas the activation of P2Y2R showed an opposite effect. Silencing of CD39 promoted the expression of ATP and P2Y2R. These results indicate that CD39 attenuates alcohol-induced steatohepatitis by scavenging extracellular ATP to indirectly regulate the expression of P2Y2R. Interestingly, P2Y2R paradoxically boosts CD39 activity. Thus, blockade of the extracellular ATP-P2Y2R signalling represents a potential therapeutic approach against alcoholic liver disease, and CD39 is a potential therapeutic target.

Characterizations of dissolved organic matter and bacterial community structures in rice washing drainage (RWD)-based synthetic groundwater denitrification.

In this study, characteristics of dissolved organic matter (DOM) and bacterial community structure in rice washing drainage (RWD)-based groundwater denitrification systems inoculated with and without seeding sludge were investigated. Complete nitrate removal was achieved with a maximum denitrification rate of 64.1 mg NO3--N·(gVSS·h)-1. Analysis of three-dimension fluorescence excitation-emission matrix (FEEM) identified three main compositions of DOM associated with tryptophan protein-like, aromatic protein-like, and polycarboxylate humic acid-like substances in the inoculated system, while one composition associated with tryptophan protein-like substance in the un-inoculated system. Illumina sequencing analysis revealed a distinguished bacterial community structure in two systems over time. Notably, the microbial diversity was significant lower in the un-inoculated system than that in the system inoculated with seeding sludge. The predominant phyla shifted from Proteobacteria (49.2%), Bacteroidetes (20.5%) and Chloroflexi (14.8%) in the seeding sludge to Bacteroidetes (56.3%) and Proteobacteria (37.7%) after the RWD addition in the inoculated system. With RWD as sole microbe source, temporal changes in the bacterial structure from Proteobacteria (99.4%) and Bacteroidetes (5.3%) to Proteobacteria (88.8%) and Bacteroidetes (10.3%) were observed in the un-inoculated system. Specific comparison down to the genus level showed the dominant denitrifying bacteria of Thiobacillus, Anaerolineaceae and Methylophilaceae in the seeding sludge. Ideonella, Cloacibacterium and Enterobacter were dominant after the RWD addition in the inoculated system, while Stenotrophomonas and Enterobacter were dominant genera when RWD as sole bacteria source in the un-inoculated system. This finding indicates that both RWD addition and inoculation had strong impacts on bacterial community structure.

Study on Flow Field Characteristics of the 90° Rectangular Elbow in the Exhaust Hood of a Uniform Push⁻Pull Ventilation Device.

A uniform push⁻pull ventilation device can effectively improve indoor air quality (IAQ). The 90° rectangular elbow is an important part of the push⁻pull ventilation device. This paper analyzes the flow field characteristics of the 90° rectangular elbows under different working conditions. This was done by using computational fluid dynamics (CFD) simulation (Fluent). The flow lines, velocity and pressure distribution patterns of the elbow flow field are revealed in detail. The wind velocity non-uniformity and wind pressure non-uniformity of the 90° rectangular elbows with different coefficients of radius curvature R and rectangular section height h are also compared. The results show that when R ≥ 2.5 h, the wind flow traces inside the elbow are basically parallel lines. At the same time, the average wind velocity and the average wind pressure are stable. Also, the wind velocity non-uniformity and wind pressure non-uniformity decrease with the increase of R. Therefore, considering the space and material loss caused by an increase in radius of curvature, the elbow with R = 2.5 h can be used as the best design structure for the 90° rectangular elbow, which is of great significance for improving the control effect of dust and toxic pollutants in a uniform push⁻pull ventilation device.

New insights into the enhancement of biochemical degradation potential from waste activated sludge with low organic content by Potassium Monopersulfate treatment.

Waste activated sludge with low organic content (WAS-LOC) always led to the failure of anaerobic fermentation. A potentially practical technology based on SO4-, i.e. Potassium Monopersulfate (PMS) was used into WAS-LOC anaerobic fermentation system and had been presented to greatly improve both the intracellular and extracellular constituents, which improved the biological enzyme activity and produced a mass of short-chain fatty acids (SCFAs). Results showed that the maximal SCFAs production was 716.72 mg chemical oxygen demand (COD)/L (0.08 mg PMS/mg SS), which increased to 43.70 times comparing to that of 0.00 mg PMS/mg SS level (16.40 mgCOD/L). The activities of biological enzymes increased 1.42 times for protease, 4.38 times for α-glucosidase, 2.1 times for alkaline phosphatase, 1.70 times for acidic phosphatase and 1.37 times for dehydrogenase respectively comparing to natural fermentation system, but the coenzyme 420 was restrained prominently. PMS positively enriched the abundance of microbial community responsible for WAS-LOC hydrolysis and SCFAs production.