RDscan: Extracting RNA-disease relationship from the literature based on pre-training model.

With the rapid advancements in molecular biology and genomics, a multitude of connections between RNA and diseases has been unveiled, making the efficient and accurate extraction of RNA-disease (RD) relationships from extensive biomedical literature crucial for advancing research in this field. This study introduces RDscan, a novel text mining method developed based on the pre-training and fine-tuning strategy, aimed at automatically extracting RD-related information from a vast corpus of literature using pre-trained biomedical large language models (LLM). Initially, we constructed a dedicated RD corpus by manually curating from literature, comprising 2,082 positive and 2,000 negative sentences, alongside an independent test dataset (comprising 500 positive and 500 negative sentences) for training and evaluating RDscan. Subsequently, by fine-tuning the Bioformer and BioBERT pre-trained models, RDscan demonstrated exceptional performance in text classification and named entity recognition (NER) tasks. In 5-fold cross-validation, RDscan significantly outperformed traditional machine learning methods (Support Vector Machine, Logistic Regression and Random Forest). In addition, we have developed an accessible webserver that assists users in extracting RD relationships from text. In summary, RDscan represents the first text mining tool specifically designed for RD relationship extraction, and is poised to emerge as an invaluable tool for researchers dedicated to exploring the intricate interactions between RNA and diseases. Webserver of RDscan is free available at https://cellknowledge.com.cn/RDscan/.

Control of Zeolite Local Polarity toward Efficient Xenon/Krypton Separation.

The inherent inertness and striking physicochemical similarities of krypton and xenon pose significant challenges to their separation. Reported herein is the efficient xenon capture and xenon/krypton adsorptive separation by transition metal-free zeolites under ambient conditions. The polarized environment of zeolite, denoted as local polarity, can be tuned by changing the topology, framework composition, and counter-cations, which in turn correlates with the guest-host interaction and separation performance. Chabazite zeolite with a framework Si/Al ratio of 2.5 and Ca2+ as the counter-cations, namely, Ca-CHA-2.5, is developed as a state-of-the-art zeolite adsorbent, showing remarkable performance, i.e., high dynamic xenon uptake, high xenon/krypton separation selectivity, and good recyclability, in the adsorptive separation of the xenon/krypton mixture. Grand Canonical Monte Carlo simulation reveals that extraframework Ca2+ cations act as the primary binding sites for xenon and can stabilize xenon molecules together with the chabazite framework, whereas krypton molecules are stabilized by weak guest-host interaction with the zeolite framework.

Association between serum omentin-1 and mucosal disease activity in patients with ulcerative colitis.

PURPOSE: Mucosal inflammation is a key feature of ulcerative colitis (UC), a chronic relapsing and remitting form of inflammatory bowel disease. Omentin-1, a newly discovered adipokine, is reported to have anti-inflammatory effects and has been found to be decreased in patients with inflammatory bowel disease. The aim of our study was to investigate the association between serum omentin-1 levels and mucosal disease activity in patients with UC. STUDY DESIGN: A total of 126 patients with UC and 77 healthy volunteers were enrolled in the study. Serum omentin-1 expression levels were measured using enzyme-linked immunosorbent assay to evaluate its potential for monitoring disease activity, including clinical and endoscopic activity. RESULTS: Serum omentin-1 levels were significantly lower in patients with UC compared to healthy controls (HC) (UC, 61.7 interquartile range: 51.5-72.6 versus healthy controls, 103.5 interquartile range: 48.3-156.2 ng/ml; P < .001). Furthermore, serum omentin-1 levels were associated with both clinical and endoscopic activity in patients with UC. Notably, omentin-1 levels were significantly lower in patients who achieved mucosal healing. Receiver operating characteristic curves indicated that serum omentin-1 levels could potentially serve as an activity index for evaluating UC. CONCLUSIONS: These findings provide further insight into the association between omentin-1 and UC, suggesting that omentin-1 may be a useful biomarker for monitoring mucosal disease activity in patients with UC.

Effects of airflow superfine pulverization on the structure, functional properties, and flavor quality of wheat bran.

BACKGROUND: Wheat bran (WB) is a byproduct of refined wheat flour production with poor edible taste and low economic value. Herein, the WB was micronized via airflow superfine pulverization (ASP), and the effects of the ASP conditions on its particle size, nutritive compositions, whiteness, hydration characteristics, moisture distribution, microstructure, cation exchange capacity, volatile flavor components, and other characteristics were investigated. RESULTS: Reducing the rotational speed of the ASP screw and increasing the number of pulverizations significantly decreased the median particle size Dx(50) of WB to a minimum of 12.97 ± 0.19 µm (P < 0.05), increased the soluble dietary fiber content from 55.05 ± 2.94 to 106.86 ± 1.60 mg g-1, and improved the whiteness and water solubility index. In addition, the water holding capacity and oil holding capacity were significantly reduced (P < 0.05), while the cation exchange and swelling capacities first increased and then decreased. Up to about 70% of water in WB exists as bound water. As the Dx(50) of WB decreased, the content of bound and immobile water increased, while the free water decreased from 14.37 ± 1.21% to 7.59 ± 1.03%. Furthermore, WB was micronized and the particles became smaller and more evenly distributed. Using gas chromatography-ion mobility spectrometry, a total of 37 volatile compounds in micronized WB (including 10 aldehydes, 9 esters, 7 alcohols, and several acids, furans, ethers, aldehydes, esters, and alcohols) were identified as the main volatile compounds of WB. CONCLUSION: Collectively, ASP improved the physicochemical properties of WB. This study provides theoretical references for the use of ASP to improve the utilization and edibility of WB. © 2024 Society of Chemical Industry.

Immobilization of the Polar Group into an Ultramicroporous Metal-Organic Framework Enabling Benchmark Inverse Selective CO2/C2H2 Separation with Record C2H2 Production.

One-step harvest of high-purity light hydrocarbons without the desorption process represents an advanced and highly efficient strategy for the purification of target substances. The separation and purification of acetylene (C2H2) from carbon dioxide (CO2) by CO2-selective adsorbents are urgently demanded yet are very challenging owing to their similar physicochemical properties. Here, we employ the pore chemistry strategy to adjust the pore environment by immobilizing polar groups into an ultramicroporous metal-organic framework (MOF), achieving one-step manufacture of high-purity C2H2 from CO2/C2H2 mixtures. Embedding methyl groups into prototype stable MOF (Zn-ox-trz) not only changes the pore environment but also improves the discrimination of guest molecules. The methyl-functionalized Zn-ox-mtz thus exhibits the benchmark reverse CO2/C2H2 uptake ratio of 12.6 (123.32/9.79 cm3 cm-3) and an exceptionally high equimolar CO2/C2H2 selectivity of 1064.9 at ambient conditions. Molecular simulations reveal that the synergetic effect of pore confinement and surfaces decorated with methyl groups provides high recognition of CO2 molecules through multiple van der Waals interactions. The column breakthrough experiments suggest that Zn-ox-mtz dramatically achieved the one-step purification capacity of C2H2 from the CO2/C2H2 mixture with a record C2H2 productivity of 2091 mmol kg-1, surpassing all of the CO2-selective adsorbents reported so far. In addition, Zn-ox-mtz exhibits excellent chemical stability under different pH values of aqueous solutions (pH = 1-12). Moreover, the highly stable framework and excellent inverse selective CO2/C2H2 separation performance showcase its promising application as a C2H2 splitter for industrial manufacture. This work paves the way to developing reverse-selective adsorbents for the challenging gas separation process.

Age-Related Differences of Cortical Topology Across the Adult Lifespan: Evidence From a Multisite MRI Study With 1427 Individuals.

BACKGROUND: Healthy aging is usually accompanied by alterations in brain network architecture, influencing information processing and cognitive performance. However, age-associated coordination patterns of morphological networks and cognitive variation are not well understood. PURPOSE: To investigate the age-related differences of cortical topology in morphological brain networks from multiple perspectives. STUDY TYPE: Prospective, observational multisite study. POPULATION: A total of 1427 healthy participants (59.1% female, 51.75 ± 19.82 years old) from public datasets. FIELD STRENGTH/SEQUENCE: 1.5 T/3 T, T1-weighted magnetization prepared rapid gradient echo (MP-RAGE) sequence. ASSESSMENT: The multimodal parcellation atlas was used to define regions of interest (ROIs). The Jensen-Shannon divergence-based individual morphological networks were constructed by estimating the interregional similarity of cortical thickness distribution. Graph-theory based global network properties were then calculated, followed by ROI analysis (including global/nodal topological analysis and hub analysis) with statistical tests. STATISTICAL TESTS: Chi-square test, Jensen-Shannon divergence-based similarity measurement, general linear model with false discovery rate correction. Significance was set at P < 0.05. RESULTS: The clustering coefficient (q = 0.016), global efficiency (q = 0.007), and small-worldness (q = 0.006) were significantly negatively quadratic correlated with age. The group-level hubs of seven age groups were found mainly distributed in default mode network, visual network, salient network, and somatosensory motor network (the sum of these hubs' distribution in each group exceeds 55%). Further ROI-wise analysis showed significant nodal trajectories of intramodular connectivities. DATA CONCLUSION: These results demonstrated the age-associated reconfiguration of morphological networks. Specifically, network segregation/integration had an inverted U-shaped relationship with age, which indicated age-related differences in transmission efficiency. EVIDENCE LEVEL: 2 TECHNICAL EFFICACY: Stage 1.

Clinical significance of a novel uric-acid-based biomarker in the prediction of disease activity and response to infliximab therapy in Crohn's disease.

OBJECTIVES: Crohn's disease (CD) is an inflammatory bowel disease marked by a chronic remission-relapse cycle. Biomarkers are critical to reflect the bowel wall inflammation and detect the treatment response. Here, we investigated a new index-the ratio of neutrophil to uric acid (NUR)-as a predictor of CD activity and responses to infliximab (IFX) treatment. METHODS: Clinical and laboratory data were retrieved for CD patients and healthy control subjects from an electronic medical records database. Disease and endoscopic activity were determined using the Crohn's Disease Activity Index (CDAI) and Simple Endoscopic Score for Crohn's Disease (SES-CD), respectively. RESULTS: We found firstly that NUR was remarkably higher in CD patients (n = 162) than controls (n = 170) (0.27 ± 0.10 vs. 0.19 ± 0.04, p < .0001). NUR was positively correlated with disease activity and prior to treatment, it was lower in CD patients who responded to IFX than in those who did not (0.25 ± 0.07 vs. 0.38 ± 0.12, p = .0019). Pre-treatment NUR was effective in predicting the patients' responses to IFX (AUC = 0.8469, p = .0034). CONCLUSION: The results of this study support the utility of NUR for detecting CD activity and predicting the response to IFX treatment.

Discovery and identification of a novel small molecule BCL-2 inhibitor that binds to the BH4 domain.

The B-cell lymphoma 2 (BCL-2) protein family plays a pivotal role in regulating the apoptosis process. BCL-2, as an antiapoptotic protein in this family, mediates apoptosis resistance and is an ideal target for cell death strategies in cancer therapy. Traditional treatment modalities target BCL-2 by occupying the hydrophobic pocket formed by BCL-2 homology (BH) domains 1-3, while in recent years, the BH4 domain of BCL-2 has also been considered an attractive novel target. Herein, we describe the discovery and identification of DC-B01, a novel BCL-2 inhibitor targeting the BH4 domain, through virtual screening combined with biophysical and biochemical methods. Our results from surface plasmon resonance and cellular thermal shift assay confirmed that the BH4 domain is responsible for the interaction between BCL-2 and DC-B01. As evidenced by further cell-based experiments, DC-B01 induced cell killing in a BCL-2-dependent manner and triggered apoptosis via the mitochondria-mediated pathway. DC-B01 disrupted the BCL-2/c-Myc interaction and consequently suppressed the transcriptional activity of c-Myc. Moreover, DC-B01 inhibited tumor growth in vivo in a BCL­2­dependent manner. Collectively, these results indicate that DC-B01 is a promising BCL-2 BH4 domain inhibitor with the potential for further development.

Discovery and characterization of a novel cGAS covalent inhibitor for the treatment of inflammatory bowel disease.

Cyclic GMP-AMP synthase (cGAS), a cytosolic DNA sensor, acts as a nucleotidyl transferase that catalyzes ATP and GTP to form cyclic GMP-AMP (cGAMP) and plays a critical role in innate immunity. Hyperactivation of cGAS-STING signaling contributes to hyperinflammatory responses. Therefore, cGAS is considered a promising target for the treatment of inflammatory diseases. Herein, we report the discovery and identification of several novel types of cGAS inhibitors by pyrophosphatase (PPiase)-coupled activity assays. Among these inhibitors, 1-(1-phenyl-3,4-dihydro-1H-pyrrolo[1,2-a]pyrazin-2-yl)prop-2-yn-1-one (compound 3) displayed the highest potency and selectivity at the cellular level. Compound 3 exhibited better inhibitory activity and pathway selectivity than RU.521, which is a selective cGAS inhibitor with anti-inflammatory effects in vitro and in vivo. Thermostability analysis, nuclear magnetic resonance and isothermal titration calorimetry assays confirmed that compound 3 directly binds to the cGAS protein. Mass spectrometry and mutation analysis revealed that compound 3 covalently binds to Cys419 of cGAS. Notably, compound 3 demonstrated promising therapeutic efficacy in a dextran sulfate sodium (DSS)-induced mouse colitis model. These results collectively suggest that compound 3 will be useful for understanding the biological function of cGAS and has the potential to be further developed for inflammatory disease therapies.

Thymoquinone attenuates hepatic lipid accumulation by inducing autophagy via AMPK/mTOR/ULK1-dependent pathway in nonalcoholic fatty liver disease.

Thymoquinone (TQ) has been proved to exert wide-ranging pharmacological activities, with anti-inflammatory, antioxidant, anticonvulsant, antimicrobial, anti-tumor, and antidiabetic properties. In this study, we investigated the beneficial effects of TQ on a high-fat diet (HFD)-induced nonalcoholic fatty liver disease (NAFLD) in C57BL/6 N mice in vivo and free fatty acid (FFA)-induced human hepatocellular carcinoma HepG2 cells in vitro. Further, the underlying mechanisms of TQ to promote hepatic autophagy were also discovered. Data showed that TQ caused (p < 0.01) body weight reduction, improved glucose homeostasis, alleviated hepatosteatosis, and decreased hepatic lipid accumulation related to the induction of autophagy in HFD-fed mice. In vitro, TQ obviously increased (p < 0.01) autophagic flux in FFA-induced HepG2 cells and consequently reduced the lipid accumulation in combination with activation of AMPK/mTOR/ULK1 signaling pathways. Moreover, pharmacological inhibition of the AMPK pathway by addition with AMPK inhibitor Compound C (CC) or silence of ULK1 by transfection with siRNA(ULK1) into HepG2 cells reversed these beneficial effects of TQ on triggering hepatic autophagy and reducing lipid accumulation (p < 0.01). Taken together, these results suggested that TQ alleviated hepatic lipid accumulation by triggering autophagy through the AMPK/mTOR/ULK1-dependent signaling pathway. Our study supports a potential role for TQ in ameliorating NAFLD.

Lead intoxication-induced exosomes promote autophagy and apoptosis in renal proximal tubule cells by activating the adenosine 5'-monophosphate-activated protein kinase signaling.

Lead (Pb) intoxication is known to damage the proximal tubules of kidney. Autophagy and apoptosis have been shown to be involved in a variety of renal injuries, but the underlying mechanisms remain largely unknown. In this study, we constructed a mice model of Pb intoxication and validated it against lead concentrations in blood and urine. Electron microscopy revealed that Pb promoted the accumulation of autophagosomes. Subsequent immunofluorescence and western blotting revealed that Pb intoxication suppressed the autophagic flux. Next, exosomes were isolated and extracted through ultracentrifugation, and were further identified by diameter analysis and marker detection. We also demonstrated that autophagy and apoptosis were enhanced in renal cells with exosomes of Pb expose. Furthermore, the specific mechanisms were explored by RNA sequencing and it was found that several targeted genes regulated by differential exosomal miRNAs and lncRNAs. Target genes accumulated in several signaling pathways, especially the adenosine 5'-monophosphate-activated protein kinase (AMPK) signaling. We found that Pb intoxication-induced exosomes activated the AMPK signaling in renal proximal tubule cells. Furthermore, autophagy and apoptosis assays showed that GSK-690693, an AMPK inhibitor, significantly alleviated exosome-induced renal injuries by Pb intoxication. In conclusion, Pb-mediated exosome-induced autophagy and apoptosis via activating the AMPK signaling contributing to Pb-induced nephrotoxicity in renal cells.

Dual spectral limited-angle CT imaging regularized by edge-preserving diffusion and smoothing.

Limited-angle CT scan is an effective way for nondestructive inspection of planar objects, and various methods have been proposed accordingly. When the scanned object contains high-absorption material, such as metal, existing methods may fail due to the beam hardening of X-rays. In order to overcome this problem, we adopt a dual spectral limited-angle CT scan and propose a corresponding image reconstruction algorithm, which takes the polychromatic property of the X-ray into consideration, makes basis material images free of beam hardening artifacts and metal artifacts, and then helps depress the limited-angle artifacts. Experimental results on both simulated PCB data and real data demonstrate the effectiveness of the proposed algorithm.

[Association between vaccination and the risk of immunoglobulin A vasculitis in children]. / ç–«è‹—æŽ¥ç§ä¸Žå„¿ç«¥å ç–«çƒè›‹ç™½Aè¡€ç®¡ç‚Žå‘ç— é£Žé™©çš„å ³è”.

OBJECTIVES: To study the effect of vaccination on the short-term risk of immunoglobulin A vasculitis (IgAV) in children. METHODS: A retrospective analysis was conducted on the general data and the vaccination history within one year prior to onset in children with IgAV hospitalized in the Children's Hospital Affiliated to Zhengzhou University from November 2021 to January 2023. Vaccine exposure rates in the risk period (3 months prior to IgAV onset) and the control period were compared by autocontrol-case crossover analysis, and the odds ratio and 95% confidence interval (95%CI) were calculated. A sensitivity analysis for the one-month and two-month risk periods was conducted. RESULTS: A total of 193 children with IgAV were included, with a median age of 7.0 years. Among the 193 children, 36 (18.7%) received at least one dose of the vaccine within 1 year prior to IgAV onset, and 14 (7.3%) received at least one dose of the vaccine during the 3-month risk period. Compared to the unvaccinated IgAV group, the vaccinated IgAV group had a significantly younger age of onset (P<0.05). There were no significant differences in the proportions of children with gastrointestinal involvement, renal involvement, and joint involvement between the two groups (P>0.05). The odds ratio for developing IgAV after receiving any type of vaccine within 3 months prior to IgAV onset was 2.08 (95%CI: 0.82-5.27, P>0.05). Further sensitivity analysis for the 1-month and 2-month risk periods demonstrated that the odds ratios for developing IgAV after receiving any type of vaccine were 2.74 (95%CI: 0.72-10.48, P>0.05) and 2.72 (95%CI: 0.95-7.77, P>0.05), respectively. CONCLUSIONS: Vaccination dose not increase the risk of IgAV, nor does it exacerbate clinical symptoms in children with IgAV.

[Relationship between coronavirus disease 2019 vaccination and the risk of immune thrombocytopenia]. / æ–°åž‹å† çŠ¶ç— æ¯’æ„ŸæŸ“ç–«è‹—æŽ¥ç§ä¸Žå ç–«æ€§è¡€å°æ¿å‡å°‘ç—‡å‘ç”Ÿé£Žé™©çš„å ³ç³».

OBJECTIVES: To study the relationship between coronavirus disease 2019 (COVID-19) vaccination and the risk of immune thrombocytopenia (ITP). METHODS: A retrospective analysis was conducted on children aged 3-17 years with newly diagnosed ITP who were hospitalized in Children's Hospital Affiliated to Zhengzhou University from November 2021 to December 2022. Clinical data and COVID-19 vaccination status were compared among three groups: ITP patients vaccinated within 12 weeks before onset, vaccinated more than 12 weeks before onset, and unvaccinated. Changes in serum immunoglobulin and complement levels were analyzed among five groups: ITP patients vaccinated <4 weeks before onset, 4-<8 weeks before onset, 8-<12 weeks before onset, ≥12 weeks before onset, and unvaccinated. A case-control design was used to estimate the risk of ITP: 387 children aged 3-17 years with fractures hospitalized during the same period in the emergency department of the hospital were selected as the control group, and the exposure to COVID-19 vaccination within 12, 8, and 4 weeks before onset in ITP children was compared to estimate the risk of ITP. RESULTS: Among 129 ITP children, there were no statistically significant differences in age, gender, rate of preceding infections, absolute platelet count at initial diagnosis, absolute lymphocyte count at initial diagnosis, bleeding score, positive anti-nuclear antibody rate, absolute platelet count after 4 days of treatment, recurrence rate, and proportion of patients with disease duration ≥3 months among the three groups vaccinated within 12 weeks before onset, vaccinated more than 12 weeks before onset, and unvaccinated (P>0.05). There was a statistically significant difference in serum immunoglobulin G, immunoglobulin A, and complement component 3 levels among the groups vaccinated <4 weeks, 4-<8 weeks, 8-<12 weeks, and ≥12 weeks before onset, and unvaccinated (P<0.05). The risk estimation results showed that COVID-19 vaccination within 12 weeks, 8 weeks, and 4 weeks before onset did not increase the risk of ITP (P>0.05). CONCLUSIONS: COVID-19 vaccination does not increase the risk of ITP.

The brain activation of anxiety disorders with emotional stimuli-an fMRI ALE meta-analysis.

Numerous studies have analyzed the state of brain activation about anxiety disorders under emotional stimuli. However, there is no meta-analysis to assess the commonality and specificity activation concerning different subtypes of anxiety. Here, we used ALE to assess this. 29 studies revealed increased bilateral amygdala, anterior cingulate gyrus, parahippocampal gyrus activation in anxiety disorders during emotional stimuli. Moreover, we observed decreased activations in the posterior cingulate, lingual gyrus, and precuneus. In sub-analysis, although different anxiety showed dissimilar activations, the principal activations were observed in limbic lobe, which might indicate the limbic circuit was the main neural reflection of anxiety symptoms.

Enhancing cofactor regeneration of cyanobacteria for the light-powered synthesis of chiral alcohols.

Cyanobacteria Synechocystis sp. PCC 6803 was exploited as green cell factory for light-powered asymmetric synthesis of aromatic chiral alcohols. The effect of temperature, light, substrate and cell concentration on substrate conversions were investigated. Under the optimal condition, a series of chiral alcohols were synthesized with conversions up to 95% and enantiomer excess (ee) > 99%. We found that the addition of Na2S2O3 and Angeli's Salt increased the NADPH content by 20% and 25%, respectively. As a result, the time to reach 95% substrate conversion was shortened by 12 h, which demonstrated that the NADPH regeneration and hence the reaction rates can be regulated in cyanobacteria. This blue-green algae based biocatalysis showed its potential for chiral compounds production in future.

The Pseudogene BMEA_B0173 Deficiency in Brucella melitensis Contributes to M-epitope Formation and Potentiates Virulence in a Mice Infection Model.

It is widely acknowledged that pseudogenes play important roles in bacterial diversification and evolution and participate in gene regulation and RNA interference (RNAi). However, the function of most pseudogenes in Brucella spp remains poorly understood, warranting further studies.To comprehensively analyze the function of the pseudogenes BMEA_B0173 in Brucella melitensis strain 63/9, a BMEA_B0173 in-frame deleted mutant strain was constructed. Then, the phenotypes of the mutant strain, such as growth characteristics and bacterial virulence, were assessed in mice infection models. Finally, iTRAQ analysis was performed to investigate the gene expression profile affected by the pseudogenes BMEA_B0173. In this study, we found that BMEA_B0173 deletion exhibited increased agglutination with M monospecific sera. In a mouse model of chronic infection, the BMEA_B0173 deletion strain displayed increased colonization in the spleen compared to the wild-type pathogen. The iTRAQ assay revealed that 252 proteins were differentially expressed between the BMEA_B0173 deletion and the wild-type strains. In addition, deletion of BMEA_B0173 significantly increased the expression of proteins involved in the denitrification pathway, iron metabolism, and several transcriptional regulators, which might cause increased virulence of the mutant strain. In conclusion, this study preliminary uncovered the function of the pseudogene BMEA_B0173 in Brucella melitensis 63/9 and provided novel insights for studying the pathogenesis of Brucella strains.

DOA Estimation for Massive MIMO Systems with Unknown Mutual Coupling Based on Block Sparse Bayesian Learning.

Obtaining accurate angle parameters using direction-of-arrival (DOA) estimation algorithms is crucial for acquiring channel state information (CSI) in massive multiple-input multiple-output (MIMO) systems. However, the performance of the existing algorithms deteriorates severely due to mutual coupling between antenna elements in practical engineering. Therefore, for solving the array mutual coupling, the array output signal vector is modeled by mutual coupling coefficients and the DOA estimation problem is transformed into block sparse signal reconstruction and parameter optimization in this paper. Then, a novel sparse Bayesian learning (SBL)-based algorithm is proposed, in which the expectation-maximum (EM) algorithm is used to estimate the unknown parameters iteratively, and the convergence speed of the algorithm is enhanced by utilizing the approximate approximation. Moreover, considering the off-grid error caused by discretization processes, the grid refinement is carried out using the polynomial roots to realize the dynamic update of the grid points, so as to improve the DOA estimation accuracy. Simulation results show that compared with the existing algorithms, the proposed algorithm is more robust to mutual coupling and off-grid error and can obtain better estimation performance.

Comammox bacteria predominate among ammonia-oxidizing microorganisms in municipal but not in refinery wastewater treatment plants.

Comammox bacteria have proved to be one dominant and significant ammonia-oxidizing microorganisms (AOMs) in municipal wastewater treatment plants (WWTPs), however, it still remains unknown about their abundance and diversity in industrial WWTPs. In this study, activated sludge samples from 8 municipal WWTPs and 6 industrial WWTPs treating refinery wastewater were taken and analyzed using qPCR and amoA gene sequencing. Intriguingly, quantitative real-time PCR (qPCR) results suggested that comammox bacteria had a higher numerical abundance compared with ammonia-oxidizing bacteria (AOB) and ammonia-oxidizing archaea (AOA) in municipal WWTPs but did not in refinery WWTPs. Moreover, comammox amoA sequences obtained from high-throughput sequencing were retrieved from all the 8 municipal samples but only 1 industrial sample. Further phylogenetic analysis revealed that N. nitrosa cluster accounted for as high as 79.56% of the total comammox affiliated sequences, which was the most numerically abundant comammox species in municipal WWTPs. This study provided new insights into the abundance and diversity of comammox bacteria in the biological nitrification process in municipal and refinery wastewater treatment systems.

The microstructure and property of Al-Si alloy improved by the Sc-microalloying and Y2O3 nano-particles.

The effect of Sc-microalloying and Y2O3 nano-particles on the microstructure and mechanical properties of as-cast Al-5.5Si alloy is studied by means of optical microscopy, transmission electron microscopy, hardness test and tensile test. The influence of annealing treatment on the microstructure and properties of the Al-Si alloys is also investigated as well. The results show that the addition of Sc and Y2O3 nano-particles could significantly improve the mechanical property of the Al-Si alloy. The ultimate tensile strength and yield strength of Al-Si-Sc/Y2O3 alloy are improved by around 45 and 71%, respectively, when compared to that of the Al-Si alloy. The effect of the nanosized particles (precipitated and added) on strengthening and deformation of Al-Si alloy is analyzed and discussed in detail. The results of annealing treatment indicate that the change in mechanical property of the Al-Si-Sc alloy during annealing treatment is mainly associated with the precipitation of the secondary Si phase.