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Aerosol microorganisms are important constituents of aerosols. They participate in physical and chemical reactions in the air and are also closely related to disease transmission and human health. With the SARS-CoV-2 pandemic， aerosol microorganisms have become a public health topic of great concern. Studying the composition and influencing factors of the air microbiome therefore has significant public health implications. Due to the limitations of traditional technologies for sampling and determination， the aerosol microbiome has not been fully understood. However， with the development and maturity of high-throughput sequencing technology， the aerosol microbiome has shown promising research prospects. This article reviews the composition， characteristics， detection methods and influencing factors of aerosol microorganisms， providing basic knowledge for further research on the air microbiome. In-depth research on microbial aerosols has significant implications on urban air quality control， national security and public health.

Objectives: To establish the reference range of normal fetal ductus venosus pulsatility index (DV PI) and ductus venosus (DV) blood flow velocity at 11–14 weeks of gestation. Material and methods: Fetal ductus venosus Doppler flow was measured in singleton pregnancies attending our hospital for early pregnancy nuchal translucency (NT) screening between June 2021 and May 2022. All fetuses were followed up for pregnancy outcome using the following inclusion criteria: Singleton pregnancy; no maternal underlying diseases such as diabetes, hypertension, rheumatism, or other pregnancy complications; fetal crown-rump length (CRL) of 45 to 84 mm; normal NT screening ultrasound; no absent or reversed ductus venosus a-wave; no fetal structural abnormalities; no chromosomal abnormalities during follow-up; and good pregnancy outcome. DV PI, peak ventricular systolic velocity (S-wave), atrial systolic flow velocity (a-wave) and time-averaged maximum velocity (TAMXV) were recorded. Results: The ductus venosus Doppler parameters of 224 fetuses which met the inclusion criteria were analysed. DV PI P5 and P95 ranged from 1.0007 and 1.3415 for a CRL of 45 mm to 0.9734 and 1.2115 for a CRL of 84 mm, indicating a statistically significant correlation with CRL. DV S-wave, a-wave, and TAMXV all increased as CRL increased, demonstrating a statistically significant correlation with CRL values. Conclusions: A reference range of normal fetal ductus venosus Doppler spectral parameters at 11–14 weeks was established to provide a basis for further research into the clinical value of normal and abnormal DV PI values in relation to adverse pregnancy outcomes. [ABSTRACT FROM AUTHOR]

The variable pressure source system is widely used in renewable energy recovery scenarios. However, the instability of the new energy input and the nonlinearity of the power generation system can lead to problems such as more difficult tracking and control of the maximum power point and poor power generation quality. To address the problem of lower efficiency under varying inputs, which is prevalent in renewable energy generation, this paper establishes an energy recovery system model based on power conversion rectifier topology, designs a speed current double closed‐loop control strategy, proposes an online variable‐step maximum efficiency point tracking method based on experience curves, and tests the overall energy recovery effect through system simulation and comparative experiments. The simulation results show that the maximum efficiency point tracking method proposed in this paper reduces the number of optimization searches by 50% and improves optimization speed. The experiment results show that, under the drastic changes of the input, the method proposed in this paper could reduce the total harmonic distortion to 5.65%, improve the energy recovery efficiency by 10.976%, and reduce the fluctuation ratio of the voltage to 2.43%. This study can provide an important reference for the collection and utilization of new energy sources. [ABSTRACT FROM AUTHOR]

Background: Within the subtypes of breast cancer pathologies, triple-negative breast cancer (TNBC) exhibits the highest degree of malignancy and unfavorable outcome, which has great significance in exploring the molecular mechanisms underlying TNBC. This study especially investigated the expression and function of hsa_circ_0003528 in TNBC. Methods: The expression changes of hsa_circ_0003528 were identified from the GEO database (GSE101123) and validated by RT-qPCR. The clinical significance of hsa_circ_0003528 was evaluated using χ2 tests and Kaplan-Meier curve analysis. Bioinformatic analysis and dual-luciferase reporter assay were used to identify the potential downstream miRNA of hsa_circ_0003528. The cellular experiments were conducted to evaluate the impact of hsa_circ_0003528 or/and miR-215 on TNBC cells. Results: The hsa_circ_0003528 was selected from the circRNA profile in breast cancer obtained from the GSE101123 dataset. hsa_circ_0003528 expression levels were increased in breast cancer tissues, especially in TNBC tissues. The elevated expression of hsa_circ_0003528 was negatively associated with TNBC patients’ overall survival. Silencing of hsa_circ_0003528 hindered the proliferative potential, migration abilities, and invasive capacities of TNBC cells, while downregulation of miR-215 partially diminished the effects of si-hsa_circ_0003528 on TNBC cells. Conclusion: hsa_circ_0003528 is upregulated in TNBC and can facilitate aggressive cellular behaviors by regulating miR-215 expression, hinting at its potential as a biomarker and therapeutic target in the treatment of TNBC. [ABSTRACT FROM AUTHOR]

This study addresses the challenges of predicting ship heave motion in real time, which is essential for mitigating sensor–actuator delays in high-performance active compensation control. Traditional methods often fall short due to training on specific sea conditions, and they lack real-time prediction capabilities. To overcome these limitations, this study introduces a multi-step prediction model based on a Seq2Seq framework, training with heave data taken from various sea conditions. The model features a long-term encoder with attention-enhanced Bi-LSTM, a short-term encoder with Gated CNN, and a decoder composed of multiple fully connected layers. The long-term encoder and short-term encoder are designed to maximize the extraction of global characteristics and multi-scale short-term features of heave data, respectively. An optimized Huber loss function is used to improve the fitting performance in peak and valley regions. The experimental results demonstrate that this model outperforms baseline methods across all metrics, providing precise predictions for high-sampling-rate real-time applications. Trained on simulated sea conditions and fine-tuned through transfer learning on actual ship data, the proposed model shows strong generalization with prediction errors smaller than 0.02 m. Based on both results from the regular test and the generalization test, the model's predictive performance is shown to meet the necessary criteria for active heave compensation control. [ABSTRACT FROM AUTHOR]

The large flow rate proportional poppet valve (PPV) finds widespread use in high‐power hydraulic systems. However, the indispensable dead‐zone nonlinearity that guarantees the safe shut‐off of the PPV will cause a tracking lag when a command goes outside the dead‐zone. The lag should be properly solved in a controller, which is a highlight of this study. Simultaneously, achieving high tracking precision in a PPV is necessary to meet the demands of advanced hydraulic systems. In this study, a practical nonlinear controller based on an integral separated disturbance observer is proposed to improve the performance of a PPV. In particular, the lag could be alleviated and the high tracking precision achieved simultaneously by enabling or disabling a disturbance observer in the proposed controller. A separation coefficient is proposed for the disturbance observer to detach the integral action from the controller and avert the deep input saturation of the pilot stage. Additionally, the command filtering technology is applied to the nonlinear controller to improve its interference resisting capacity in the industrial environment. The stability and effectiveness of the proposed controller are proved in theory and verified by experiments. [ABSTRACT FROM AUTHOR]