Responses of microbial interactions and functional genes to sulfamethoxazole in anammox consortia.

Sulfamethoxazole (SMX) has been widely detected in various environments and its potential environmental risks have caused great concerns. However, the impact mechanism of SMX on microbial interactions among anammox consortia remain unknown. A long-term exposure experiments (140 d) was carried out to systematically examine the influence of SMX (0-1000 µg/L) on the anammox system, especially microbial network dynamics and variations of key metabolic genes. Results showed that anammox system could adapt to SMX below 500 µg/L and maintain a high nitrogen removal efficiency (NRE) of 85.35 ± 2.42%, while 1000 µg/L SMX significantly decreased the abundance of functional microbes and deteriorated denitrification performance with NRE dropped to 36.92 ± 15.01%. Co-occurrence network analysis indicated that 1000 µg/L SMX decreased the interactions between Proteobacteria and Chloroflexi and limited AnAOB from playing an important role as central nodes in the subnetwork of Planctomycetes. Metagenomics analysis found that genes associated with nitrogen removal (i.e., hdh, hzs, nirS, and hao) showed lower expression level after addition of SMX, while SMX-related ARGs (sul1 and sul2) increased by 1.22 and 2.68 times. This study provided us a relatively comprehensive perspective in response of microbial interactions and metabolic activity to various SMX concentrations.

Associations of Musical Activities and Positive Affect With Fear of Childbirth: A Structural Equation Modeling Approach.

Background: Fear of childbirth is a prevalent issue among women, with a wide range of interventions to dispel it. Here we explored a novel and beneficial intervention and one possible influence mechanism of it. Methods: The cross-sectional study recruited 1,053 pregnant women from one tertiary-grade A class hospital between March to August 2021. The questionnaire included demographic characteristics, a self-made musical activities questionnaire, the Positive affect subscale, and the Childbirth Attitudes Questionnaire. We parceled the eight musical activities into three items by item parceling methodology. The associations of musical activities and positive affect with fear of childbirth were evaluated by a structural equation modeling approach. Results: Our analyses demonstrated the effectiveness of musical activities, which was notably correlated with the increase in positive affect (ß = 0.309, P < 0.01). On the contrary, positive affect predicted a decrease in fear of childbirth (ß = -0.085, P = 0.019). Additionally, positive affect mediated the effect of musical activities on fear of childbirth (ß = -0.026, P = 0.030). However, the direct effect of musical activities on fear of childbirth was not found (ß = 0.029, P = 0.514). Conclusions: Relying on musical activities alone may not be adequate to alleviate the fear of childbirth, and positive affect played a pivotal role between musical activities and fear of childbirth. The results showed that musical activities would be an effective non-pharmaceutical way to alleviate the fear of childbirth and positive affect can not be ignorant in future childbirth fear reduction programs.

Shifts of bacterial community and molecular ecological network in activated sludge system under ibuprofen stress.

The major objectives of this study were to explore the long-term effects of ibuprofen (IBP) on nutrient removal, community compositions, and microbial interactions of the activated sludge system. The results showed that 1 mg/L IBP had no inhibitory effects on the removal of organic matters and nutrients. IBP significantly reduced the microbial diversity and changed the bacterial community structure. Some denitrifiers (Denitratisoma and Hyphomicrobium) increased significantly, while NOB (Nitrospira) significantly decreased under IBP stress (P < 0.05). Furthermore, molecular ecological network analysis indicated that IBP reduced the overall network size and links, but led to a closer network with more efficient communication, which might be the strategy of microbes to survive under the stress of IBP and further maintain the performance stability. Different phylogenetic populations had different responses to IBP, as a closer subnetwork with more synergistic relations was observed in Chloroflexi and a looser subnetwork with more competitive relationships was detected in Proteobacteria. The topological roles of nodes significantly changed, and the putative keystone species decreased under the stress of IBP. This study broadens our knowledge of the long-term effects of IBP on the microbial community structure and the interactions between species in the activated sludge system.

A Hybrid Model for Coronavirus Disease 2019 Forecasting Based on Ensemble Empirical Mode Decomposition and Deep Learning.

BACKGROUND: The novel coronavirus pneumonia that began to spread in 2019 is still raging and has placed a burden on medical systems and governments in various countries. For policymaking and medical resource decisions, a good prediction model is necessary to monitor and evaluate the trends of the epidemic. We used a long short-term memory (LSTM) model and the improved hybrid model based on ensemble empirical mode decomposition (EEMD) to predict COVID-19 trends; Methods: The data were collected from the Harvard Dataverse. Epidemic data from 21 January 2020 to 25 April 2021 for California, the most severely affected state in the United States, were used to develop an LSTM model and an EEMD-LSTM hybrid model, which is an LSTM model combined with ensemble empirical mode decomposition. In this study, ninety percent of the data were adopted to fit the models as a training set, while the subsequent 10% were used to test the prediction effect of the models. The mean absolute percentage error, mean absolute error, and root mean square error were used to evaluate the prediction performances of the models; Results: The results indicated that the number of confirmed cases in California was increasing as of 25 April 2021, with no obvious evidence of a sharp decline. On 25 April 2021, the LSTM model predicted 3666418 confirmed cases, whereas the EEMD-LSTM predicted 3681150. The mean absolute percentage errors for the LSTM and EEMD-LSTM models were 0.0151 and 0.0051, respectively. The mean absolute and root mean square errors were 5.58 × 104 and 5.63 × 104 for the LSTM model and 1.9 × 104 and 2.43 × 104 for the EEMD-LSTM model, respectively; Conclusions: The results showed the advantage of an EEMD-LSTM model over a single LSTM model, and the established EEMD-LSTM model may be suitable for monitoring and evaluating the epidemic situation and providing quantitative analysis evidence for epidemic prevention and control.

Epsilon negative-based, broadband single-polarization single-mode hollow core anti-resonant photonic crystal fiber.

A broadband single-polarization single-mode (SPSM) hollow core anti-resonant photonic crystal fiber (HC-ARPCF) is proposed and analyzed by the finite element method in this paper. The HC-ARPCF design consisted of outer semicircular cladding tubes and inner circular cladding tubes. The SPSM behavior is achieved through controlling the effective material absorption loss (EML) by loading epsilon negative (ENG) material in the selected semicircular cladding tubes. Optimization of the configuration parameters is conducted to yield a large loss difference (LD) between one of the two orthogonally polarized fundamental modes and all the other unwanted modes. Therefore, only one desired mode will exist after a proper propagation distance, i.e., SPSM guidance. Specially, the optimal design provides a 288 nm (from 1408 nm to 1676 nm and from 1680 nm to 1700 nm) bandwidth in terms of 40 dB/m minimum LD (MLD) and 168 nm (from 1452 nm to 1620 nm) bandwidth in terms of 100 dB/m MLD. Furthermore, this fiber also exhibits a large effective mode area and near-zero dispersion properties over the entire operation bandwidth. The proposed HC-ARPCF may find its applications in polarization maintaining and high-power laser systems.

A Highly Birefringent Photonic Crystal Fiber for Terahertz Spectroscopic Chemical Sensing.

A photonic crystal fiber (PCF) with high relative sensitivity was designed and investigated for the detection of chemical analytes in the terahertz (THz) regime. To ease the complexity, an extremely simple cladding employing four struts is adopted, which forms a rectangular shaped core area for filling with analytes. Results of enormous simulations indicate that a minimum 87.8% relative chemical sensitivity with low confinement and effective material absorption losses can be obtained for any kind of analyte, e.g., HCN (1.26), water (1.33), ethanol (1.35), KCN (1.41), or cocaine (1.50), whose refractive index falls in the range of 1.2 to 1.5. Besides, the PCF can also achieve high birefringence (∼0.01), low and flat dispersion, a large effective modal area, and a large numerical aperture within the investigated frequency range from 0.5 to 1.5 THz. We believe that the proposed PCF can be applied to chemical sensing of liquid and THz systems requiring wide-band polarization-maintaining transmission and low attenuation.

Successional Dynamics of Molecular Ecological Network of Anammox Microbial Communities under Elevated Salinity.

Response of microbial interactions to environmental perturbations has been a central issue in wastewater treatment system. However, the interactions among anammox microbial community under salt perturbation is still unclear. Here, we used random matrix theory (RMT)-based network analysis to investigate the dynamics of networks under elevated salinity in an anammox system. Results showed that high salinity (20 and 30 g/L NaCl) inhibited anammox performance. Salinity led to closer and more complex networks for the overall network and subnetwork of Planctomycetes and Proteobacteria, especially under low salinity (5 g/L NaCl), which could serve as a strategy to survive under salt perturbation. Planctomycetes, most dominant phylum and playing crucial roles in anammox, possessed higher proportion of competitive relationships (64.3%) under 30 g/L NaCl. OTU 109 (closely related to Ignavibacterium), the only network hub detected in the anammox system, also had larger amount of competitive relationships (27.3%) than the control (0%) under 30 g/L NaCl. Similar result was found for the most abundant keystone bacteria Candidatus Kuenenia. These increasing competitions at different taxa level could be responsible for the deterioration of nitrogen removal. Besides, all the network topological features tended to reach the values of the original network, which showed the network of microbial community could gradually adapt to the elevated salinity. Microbial network analysis adds a different dimension for our understanding of the response in microbial community to elevated salinity.

Shifts of bacterial community and molecular ecological network at the presence of fluoroquinolones in a constructed wetland system.

Fluoroquinolones (FQs) has caused increasing concerns regarding its potential environmental risks. However, their effects on bacterial community and microbial interactions in wetland system remains unclear. To verify these issues, a lab-scale constructed wetland exposed to low concentration FQs mixture was carried out for two months. The results showed that the removal efficiencies of COD and TP were negatively affected. FQs significantly increased the bacterial diversity and altered the overall bacterial community structure. Proteobacteria significantly decreased while Firmicutes exhibited opposite tendency (P < 0.05). Dechloromonas and Delftia, involved in phosphorus removal, decreased significantly (P < 0.05). Molecular ecological network analysis suggested that FQs promoted the network complexity and microbial interactions. A super module emerged at FQs and among-module connections were weakened obviously. Additionally, Nodes of Betaproteobacteria lost most interactions while Clostridia acquired more interactions at the presence of FQs. This study provided insights into how the bacterial community and their molecular ecological network respond to FQs in constructed wetland system.