Increasing attention has been paid to the anammox community for its significant function in high-efficiency wastewater treatment. However, bacterial interaction in terms of bacterial communication is ...still elusive. This study firstly explored the intra- and interspecific communication of bacteria in the anammox community using metagenomic sequence data obtained during bioreactor operation. We verified the existence of multiple bacterial communication gene (BCG) subtypes by alignment with the constructed BCG database containing 11 identified gene subtypes. Bacterial communication was more active at the initial start-up than in the high loading-rate phase, and was correlated with the gradually decreasing bacterial diversity. Hdts, one of the key genes that produced the intraspecific signaling molecule AHL, and RpfF, the key gene that produced the intra- and interspecific signaling molecule DSF, were the primary communication engines in the anammox community because of their high abundance. Anammox bacteria mainly used Hdts genes to communicate with others, while RpfF gene played a core role characterized by their multiple correlations with other BCG subtypes. Interestingly, bacteria with abundant BCGs were more inclined to interact with the bacteria with the same functional traits, indicating the potential communication-related interaction among these bacteria in addition to the frequently reported substrate co-utilization. This highlights the primary importance of AHL and DSF for the anammox community, and thereby hints at a potential strategy for the target regulation of the signals to improve anammox viability and competitive capacity in wastewater treatment.
Display omitted
•Intra- and interspecific bacterial communication in anammox culture are verified.•HdtS and RpfF genes are important engines for communication during start-up.•Anammox bacteria use HdtS genes to communicate.•RpfF genes plays a core role in intra- and interspecific species communication.•Bacteria are inclined to communicate with other bacteria with the same function.
Gaining mechanistic understanding of oxygen activation on metal surfaces is a topical area of research in surface science. However, direct investigation of on‐surface oxidation processes at the ...nanoscale and the empirical validation of oxygen activation pathways remain challenging for the conventional analytical tools. In this study, we applied tip‐enhanced Raman spectroscopy (TERS) to gain mechanistic insights into oxygen activation on bulk Au(111) surface. Specifically, oxidation of 4‐aminothiophenol (4‐ATP) to 4‐nitrothiophenol (4‐NTP) on Au(111) surface was investigated using hyperspectral TERS imaging. Nanoscale TERS images revealed a markedly higher oxidation efficiency in disordered 4‐ATP adlayers compared to the ordered adlayers signifying that the oxidation of 4‐ATP molecules proceeds via interaction with the on‐surface oxidative species. These results were further validated via direct oxidation of the 4‐ATP adlayers with H2O2 solution. Finally, TERS measurements of oxidized 4‐ATP adlayers in the presence of H2O18 provided the first empirical evidence for the generation of oxidative species on bulk Au(111) surface via water‐mediated activation of molecular oxygen. This study expands our mechanistic understanding of oxidation chemistry on bulk Au surface by elucidating the oxygen activation pathway.
Oxygen activation on bulk Au(111) surface is revealed for the first time using tip‐enhanced Raman spectroscopy. Activation of molecular oxygen on bulk Au(111) surface is found to occur via a water‐promoted mechanism.
Modified combined short and long axis method (MCSL) can replace oblique axis in-plane method (OA-IP) for internal jugular vein cannulation (IJVC). This randomized, non-inferiority study estimated the ...efficacy of MCSL compared with OA-IP in right IJVC.
Patients (18-75 yr. old) undergoing right IJVC under local anesthesia were randomly assigned to MCSL or OA-IP group. The primary outcome is the event of first needle pass without posterior vessel wall puncture (PVWP). Secondary outcomes included needle attempts, success rate, puncture and cannulation time, needle visualization, probe placement difficulty and complications.
Among 190 randomized patients, 187 were involved in the analysis. The first needle pass without PVWP was 85(89.47%) in the MCSL and 81 (85.26%) in the OA-IP (p = 0.382), with a mean rate difference of 4.2% (95% confidence interval: -5.2-13.6), which confirmed the non-inferiority with the margin of -8%. MCSL group exhibited shorter procedure time and lower complications than OA-IP group. No significant differences were discovered between groups in needle attempts, success rate, incidence of probe placement difficulty and needle visualization.
MCSL is non-inferior to OA-IP in first needle pass without PVWP in adults who underwent elective right IJVC and associate with less complications and shorter operating time.
ChiCTR, ChiCTR2100046899.
Named entity recognition is a key prerequisite for many tasks. However, the high cost of entity annotation limits feature learning and generalization capabilities of models. To address this problem, ...this paper integrates the weakly supervised method with first-order logic for Chinese named entity recognition. Firstly, a knowledge base is established by using first-order logic, tailored to the characteristics of the Chinese named entity recognition dataset. Secondly, self-training approach is introduced to address the issue of suboptimal feature learning in the model, stemming from a limited number of entity types. Lastly, the first-order logic knowledge base is incorporated into self-training approach to rectify mislabeling in the training process, which improves the generalization ability. The F1-score on the public datasets ACE05 and MSRA are improved by 2.56% and 0.35% respectively.
Display omitted
•Verified the existence of QS communication system among anammox bacteria.•Confirmed the release of C6-HSL, C8-HSL, C12-HSL by anammox culture.•C6-HSL and C8-HSL increased activity ...and growth rate of anammox bacteria.•Additional signals activated bacteria by inducing endogenous signals in bacteria.•Opened a new window to accelerate the start-up period of anammox reactor.
Quorum sensing (QS) is a microorganism communication system. This study verified the potential existence of the QS system among ANaerobic AMMonium OXidation (anammox) bacteria. The release of three Acyl Homoserine Lactones (AHLs; C6-HSL, C8-HSL, C12-HSL) by anammox culture was confirmed. By conducting series of batch test, the introduction of exogenous C6-HSL and C8-HSL could significantly increase activity of anammox bacteria, and meanwhile, C6-HSL significant increased the growth rate, finally resulting in the increased ammonium nitrogen removal performance of 35% and 20%, respectively, whereas the exogenous C12-HSL apparently promoted the growth of heterotrophic bacteria in the community. To further identify how exogenous signal molecular affects anammox culture, analyses of anammox culture supernatant and biomass extraction revealed that these additional signal molecules activated bacteria by inducing the production of endogenous signal molecular by anammox culture. This study might open a new window to overcome the disadvantage of the long-start-up period of anammox reactor restricting the development of current anammox process.
The granulation of anaerobic ammonium oxidation (Anammox) biomass plays a key role in high rate performance of upflow-type Anammox reactors. However, the formation of cavitation inside granules may ...result in sludge flotation problem, which negatively affects the operation stability. For quantitative evaluation of the Anammox granules flotation in upflow reactors, an integrated mathematical model was formulated based on the principles that the limitation of substrate diffusion would result in bacterial starvation, lysis and subsequently aiding the formation of cavitation in the inner zone of granules. The proposed model is used to investigate the possible mechanism of cavitation formation and granules flotation. The combined modelling and experimental results showed that the model predictions matched well with the actual floating behavior of granules (R2 = 0.83 for settled sludge and 0.76 for floating sludge). Based on the model results, the granule flotation could be divided into three zones namely (i) no-flotation zone (no flotation occurrence), (ii) transition zone (flotation with a part of granules), and (iii) flotation zone (inevitable flotation occurrence). The floating behavior of granules was mainly influenced by granule diameter (2.5–4.5 mm) and substrate concentration (NO2–N, 50–250 mg/L) in the transition zone. The optimum granule diameter to avoid flotation but with excellent settling performance was identified around 2.5 mm. Additionally, the granule size is more sensitivity to flotation than substrate concentration. Hence, controlling the size of granules is more important to alleviate granule flotation in Anammox reactors’ operation.
Display omitted
•A novel model on Anammox granule flotation was developed based on cell lysis and cavitation.•Granule floating behavior can be assessed by substrate concentration and diameter.•Reactor operating conditions must be kept in no-flotation and transition zones.•Flotation potential increases with the rise in cavitation inside Anammox granules.
Acyl-homoserine lactones (AHLs)-mediated quorum sensing in bacterial communities have been extensively observed. However, the metabolic pathways regulated by AHLs in bacteria remain elusive. Here, we ...combined long-term reactor operation with microbiological and metabolomics analyses to explore the regulatory pathways for different AHLs in anammox consortia, which perform promising nitrogen removal for wastewater treatment. The results showed that no obvious shifts induced by exogenous AHLs occurred in the microbial community and, mainly, dosing AHLs induced changes in the metabolites. 3OC6-HSL, C6-HSL, and C8-HSL controlled the electron transport carriers that influence the bacterial activity. In contrast, only 3OC6-HSL regulated LysoPC(20:0) metabolism, which affected bacterial growth. AHLs mainly regulated the synthesis of the amino acids Ala, Val, and Glu and selectively regulated Asp and Leu to affect extracellular proteins. Simultaneously, all the AHLs regulated the ManNAc biosynthetic pathways, while OC6-HSL, OC8-HSL, and C6-HSL particularly enriched the UDP-GlcNAc pathway to promote exopolysaccharides, resulting in different aggregation levels of the anammox consortia. Our results not only provide the first metabolic insights into the means by which AHLs affect anammox consortia but also hint at potential strategies for overcoming the limitations of the long start-up period required for wastewater treatment by anammox processing.
Platelet-derived growth factors (PDGFs) and PDGF receptors (PDGFRs) are expressed in a variety of tumors. Activation of the PDGF/PDGFR signaling pathway is associated with cancer proliferation, ...metastasis, invasion, and angiogenesis through modulating multiple downstream pathways, including phosphatidylinositol 3 kinase/protein kinase B pathway and mitogen-activated protein kinase/extracellular signal-regulated kinase pathway. Therefore, targeting PDGF/PDGFR signaling pathway has been demonstrated to be an effective strategy for cancer therapy, and accordingly, some great progress has been made in this field in the past few decades. This review will focus on the PDGF isoforms and their binding with the related PDGFRs, the PDGF/PDGFR signaling and regulation, and especially present strategies and inhibitors developed for cancer therapy, and the related clinical benefits and side effects.
Ultrasound-guided internal jugular vein (IJV) catheterization has become a standard procedure as it yields a higher success rate and fewer mechanical complications compared with an anatomical ...landmark technique. There are several common methods for ultrasound guidance IJV catheterization, such as short-axis out-of-plane, long-axis in-plane and oblique axis in-plane, but these technologies are still developing. It is important to further study the application of different ultrasound-guided IJV puncture techniques and find an effective and safe ultrasound-guided puncture technique.
A China randomized, open-label, parallel, single center, positive-controlled, non-inferiority clinical trial will evaluate 190 adult patients undergoing elective surgery and need right jugular vein catheterization. Study participants randomized in a 1:1 ratio into control and experimental groups. The control group will take the oblique axis in-plane method for IJV catheterization. The experimental group will take the Modified combined short and long axis method. The primary endpoint of the trial is the rate of one-time successful guidewire insertion without posterior wall puncture (PWP). Secondary endpoints are the number of needle insertion attempts, the total success rate, the procedure time, and mechanical complications.
This randomized controlled trial will evaluate the effectiveness and safety of Modified combined short and long axis method and oblique axis in-plane method for right IJV catheterization in adult patients.
The grain contamination by
spp. has been a serious issue. This study exhibited the excellent antifungal effects of the essential oil compounds (EOCs) geraniol and citral against common grain ...pathogens (
and
) in vitro and in situ. The inhibitory mechanisms were also evaluated from the perspective of cell membrane permeability, reactive oxygen species (ROS) generation, and
spp. growth-related gene expression. Meanwhile, the combined effects of EOCs in the vapor phase and modified atmosphere packaging (MAP) were examined to find an alternative preservation method for controlling
spp. The results indicated that citral exhibited the antifungal activity mainly by downregulating the sporulation- and growth-related genes for both pathogens. Geraniol displayed inhibitory effectiveness against
predominantly by inducing the intracellular ROS accumulation and showed toxicity against
principally by changing cell membrane permeability. Furthermore, the synthetic effects of EOCs and MAP (75% CO₂ and 25% N₂) induced better grain quality than the current commercial fumigant AlP. These findings reveal that EOCs have potential to be a novel grain preservative for further application.
PDF