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Solar panels often suffer from dust accumulation, significantly reducing their output, especially in desert regions where many of the worlds largest solar plants are located. Here, an autonomous dust removal system for solar panels, powered by a wind-driven rotary electret generator is proposed. The generator applies a high voltage between one solar panels output electrode and an upper mesh electrode to generate a strong electrostatic field. It is discovered that dust particles on the insulative glass cover of the panel can be charged under the high electrical field, assisted by adsorbed water, even in low-humidity environments. The charged particles are subsequently repelled from the solar panel with the significant Coulomb force. Two panels covered with sand dust are cleaned in only 6.6 min by a 15 cm diameter rotary electret generator at 1.6 m s-1 wind speed. Experimental results manifest that the system can work effectively in a wide range of environmental conditions, and doesnt impact the panel performance for long-term operation. This autonomous system, with its high dust removal efficiency, simplicity, and low cost, holds great potential in practical applications.

This work uses supervised learning to optimize the package design with validated experimental results for piezoelectric micromachined ultrasonic transducers (PMUTs) to increase and alter the sound pressure level (SPL). Advancements as compared to the state-of-art include: (1) a neural network model to achieve a mean squared error of less than 0.65 dB2 post 100 epochs; (2) increased vibration amplitude by 17.9 dBV at the first-mode resonance frequency of 33.5 kHz; and (3) SPL enhancements below the 20 kHz frequency range such as the magnitude increases of more than 60 dBV at 5 kHz. As such, the package design shifts the emitting acoustic energy from the ultrasound to audio range in favor of various applications, including audio speakers.

This work presents a continuous volumetric indoor air temperature measurement scheme using PMUTs (piezoelectric micromachined ultrasonic transducers). Advancements as compared to state-of-art works include: (1) 'volumetric' temperature monitoring instead traditional 'pointwise' temperature information; (2) accurate temperature readings spanning an operational distance of 5 m as validated by a commercial thermometer for 3 days; and (3) capable of detecting global average temperature and local temperature events by installing networked/grid PMUT pairs. This innovative sensing technique could be applicable for the precision control of future building/living environments.

We present a surface-tension driven electrochemical liquid metal (LM) actuator without the gas-producing side-reaction and capable of fabrication/operation in ambient air for practical applications. A hybrid supercapacitor is introduced to inhibit the common counter electrode side reactions, and the use of quasi-solid-state ionic hydrogel instead of liquid electrolyte further enables non-volatile operations. A 2×4 LM droplet array is demonstrated to actuate by a low driving voltage of 3.5 V for a maximum force of ~8.5 mN and a displacement of 0.56 mm in only 1.75 s. With the favorable scaling law of surface tension, further miniaturization could provide new opportunities in applications such as micro-robots, microfluidics, soft robots, and so on.

This paper reports a 9-meter-long ultrasonic 3D detector based on a packaged lithium niobate PMUTs (piezoelectric micromachined ultrasonic transducers). Compared with the state-of-the-art reports, three distinctive achievements have been demonstrated: (1) high uniformity and wide bandwidth PMUTs by optimized package designs for highly efficient ultrasonic energy transfer; (2) a long-range receiving beamforming detection scheme on a 4×4 PMUT array for up to 9 m detection rang - comparable to the longest reported range via PMUTs; and (3) 3D detection of multiple static/moving objects with the field of view exceeding 50°. As such, this device is valuable for various applications such as obstacle avoidance when both low power consumption and small form factor are desirable, including aerial drones.

Soft actuators with unique mechanics have gained significant interests for unique capabilities and versatile applications. However, their actuation mechanisms (usually driven by light, heat, or chemical reactions) result in long actuation times. Reported magnetically actuated soft actuators can produce rapid and precise motions, yet their complex manufacturing processes may constrain their range of applications. Here, the “bone-in-flesh” is proposed that constructs combining rigid magnetic structures encapsulated within soft polymers to create untethered magnetic soft actuators. This approach enables these soft, impact-resistant, agile actuators with a significantly simplified fabrication process. As demonstration examples, multiple soft actuators are fabricated and tested, including actuators for auxetic properties, 2D–3D transformations, and multi-stable states. As such, this work offers a promising solution to challenges associated with soft actuators to potentially expand their applications in various domains.

Abstract Background Decision fatigue is a new concept in the field of psychology and refers to a state of fatigue alongside impaired cognitive processing and emotional regulation ability. Previous studies have confirmed that nurses are prone to decision fatigue, and nurses who experience decision fatigue may implement nursing measures that are inconsistent with clinical evidence, thus affecting patients’ benefits. COVID-19, as a large-scale global public health emergency, increased the workload and burden of nurses and aggravated decision fatigue. However, the factors leading to decision fatigue among nurses have not yet been identified. Methods This study is guided by interpretative phenomenology. During the epidemic period of COVID-19: From November 2022 to February 2023, a one-to-one, semi-structured in-depth interview was conducted among nurses with decision fatigue experience who were participating in front-line work in Jilin Province using homogenous sampling. The interview recordings and related data were transcribed into text within 24 h, and data analysis was assisted by NVivo 12.0 software. Results After a total of 14 front-line nurses were analyzed in this study, The thematic level reaches saturation, the findings present a persuasive and coherent narrative, and the study is terminated, and finally extracted and formed three core themes: “Cognition, influence and attitude of decision fatigue”, “Approaching factors of decision fatigue” and “Avoidant factors of decision fatigue”. Conclusion This study confirmed that decision fatigue was widespread in the work of front-line nurses, affecting the physical and psychological health of nurses, the quality of nursing work, the degree of benefit of patients and the clinical outcome. However, nursing staff do not know enough about decision fatigue, so the popularization and research of decision fatigue should be strengthened. Improve the attention of medical institutions, nursing managers and nursing staff.Some suggestions are put forward for the intervention of decision fatigue through personnel, task, tool and technology, organization and environment.

Abstract Eunicellane diterpenoids, containing a typical 6,10-bicycle, are bioactive compounds widely present in marine corals, but rarely found in bacteria and plants. The intrinsic macrocycle exhibits innate structural flexibility resulting in dynamic conformational changes. However, the mechanisms controlling flexibility remain unknown. The discovery of a terpene synthase, MicA, that is responsible for the biosynthesis of a nearly non-flexible eunicellane skeleton, enable us to propose a feasible theory about the flexibility in eunicellane structures. Parallel studies of all eunicellane synthases in nature discovered to date, including 2Z-geranylgeranyl diphosphate incubations and density functional theory-based Boltzmann population computations, reveale that a trans-fused bicycle with a 2Z-configuration alkene restricts conformational flexibility resulting in a nearly non-flexible eunicellane skeleton. The catalytic route and the enzymatic mechanism of MicA are also elucidated by labeling experiments, density functional theory calculations, structural analysis of the artificial intelligence-based MicA model, and mutational studies.

Abstract Given the existing uncertainty regarding the effectiveness and safety of switching from low-molecular-weight heparin (LMWH) to direct oral anticoagulants (DOACs) in patients with cancer-associated venous thrombosis (CAT), we conducted a comprehensive population-based cohort study utilizing electronic health database in Hong Kong. A total of 4356 patients with CAT between 2010 and 2022 were included, with 1700 (39.0%) patients switching to DOAC treatment. Compared to continuous LMWH treatment, switching to DOACs was associated with a significantly lower risk of hospitalization due to venous thromboembolism (HR: 0.49 [95% CI = 0.35–0.68]) and all-cause mortality (HR: 0.67 [95% CI = 0.61–0.74]), with no significant difference in major bleeding (HR: 1.04 [95% CI = 0.83–1.31]) within six months. These findings provide reassurance regarding the effectiveness and safety of switching from LMWH to DOACs among patients with CAT, including vulnerable patient groups.

Background Surgical treatment for hinge failure in mega‐prosthesis continues to be a challenge. This study introduces a new method for treating hinge failure by using a unilateral prosthesis and hinge revision. Case Presentation We here present two patients who underwent mega‐prosthesis reconstruction after resection of osteosarcoma in the distal femur. To address the issue of knee hyperextension after mega‐prosthesis reconstruction, one patient underwent three revision surgeries, two surgeries were performed using the original hinge, and one surgery involved a newly designed hinge. To resolve the problem of dislocation, one patient underwent three revisions, with the first two revisions not involving hinge replacement and the third revision involving a newly designed hinge. Two replacements of unilateral prosthesis and hinge renovations were successful. Conclusions Unilateral prosthesis and newly designed hinge device revision are effective in treating the failure of old‐fashioned mega‐prosthesis hinges.

Abstract Background The objective of this research is to investigate the dynamic developmental trends between Age-Friendly Environments (AFE) and healthy aging in the Chinese population. Methods This study focused on a sample of 11,770 participants from the CHARLS and utilized the ATHLOS Healthy Aging Index to assess the level of healthy aging among the Chinese population. Linear mixed model (LMM) was used to explore the relationship between AFE and healthy aging. Furthermore, a cross-lagged panel model (CLPM) and a random-intercept cross-lagged panel model (RI-CLPM) were used to examine the dynamic developmental trends of healthy aging, taking into account both Between-Person effects and Within-Person effects. Results The results from LMM showed a positive correlation between AFE and healthy aging (β = 0.087, p

Postoperative delayed gastric emptying is a prevalent complication following surgical procedures, imposing heavy physical and financial burdens on patients. However, current treatment options remain suboptimal. In recent years, an increasing number of studies have highlighted that the gut microbiota and its metabolites are closely associated with postoperative complications. Various factors can disrupt the gut microbiome after surgery. This review discusses the potential mechanisms by which the gut microbiota and their metabolites may contribute to the pathogenesis of postoperative delayed gastric emptying. However, the current knowledge base is limited in terms of fully understanding the exact mechanisms involved. It is therefore evident that further research is required to fully elucidate the role of the gut microbiome in postoperative delayed gastric emptying, with the aim of uncovering new possibilities for preventive measures and therapeutic treatments.

Abstract Background Epilepsy is a chronic neurological disorder that is more likely to be diagnosed in children. The main treatment involves long-term use of anti-epileptic drugs and above all, home care is of great importance. As there has not been a widely accepted home care protocols, simulating a home care environment is necessary for caregivers to develop skills of proper home care. This study aims to evaluate the effectiveness of a simulation training of family management style (STOFMS) for parents of children with epilepsy in China. Methods A randomized controlled trial was conducted on 463 children with epilepsy and their families. They were recruited from March 2020 to November 2022 and randomly assigned to the STOFMS group or the conventional group in a 1:1 ratio. Scores of family management measures, 8-item of Morisky Medication Adherence and epilepsy clinical symptom of both groups were collected at three points of time: within 24 h after admission (T0), 3 months after discharge (T1), and 6 months after discharge (T2). Changes due to intervention were compared across groups by repeated-measures ANOVA. The study report followed the CONSORT 2010 checklist. Results There were statistically significant differences between the two groups at T2. A considerable increase over the baseline was observed in the total management level score and subscale scores in the STOFMS group at T1, compared with essentially no change in the control group. In terms of medication adherence, the STOFMS group performance improved greatly at T1 and T2 compared with the control group. The same result was also found in clinical efficacy at T2 (p

Abstract Background The popularity of Muscovy ducks is attributed not only to their conformation traits but also to their slightly higher content of breast and leg meat, as well as their stronger-tasting meat compared to that of typical domestic ducks. However, there is a lack of comprehensive systematic research on the development of breast muscle in Muscovy ducks. In addition, since the number of skeletal muscle myofibers is established during the embryonic period, this study conducted a full-length transcriptome sequencing and microRNA sequencing of the breast muscle. Muscovy ducks at four developmental stages, namely Embryonic Day 21 (E21), Embryonic Day 27 (E27), Hatching Day (D0), and Post-hatching Day 7 (D7), were used to isolate total RNA for analysis. Results A total of 68,161 genes and 472 mature microRNAs were identified. In order to uncover deeper insights into the regulation of mRNA by miRNAs, we conducted an integration of the differentially expressed miRNAs (known as DEMs) with the differentially expressed genes (referred to as DEGs) across various developmental stages. This integration allowed us to make predictions regarding the interactions between miRNAs and mRNA. Through this analysis, we identified a total of 274 DEGs that may serve as potential targets for the 68 DEMs. In the predicted miRNA‒mRNA interaction networks, let-7b, miR-133a-3p, miR-301a-3p, and miR-338-3p were the hub miRNAs. In addition, multiple DEMs also showed predicted target relationships with the DEGs associated with skeletal system development. These identified DEGs and DEMs as well as their predicted interaction networks involved in the regulation of energy homeostasis and muscle development were most likely to play critical roles in facilitating the embryo-to-hatchling transition. A candidate miRNA, miR-301a-3p, exhibited increased expression during the differentiation of satellite cells and was downregulated in the breast muscle tissues of Muscovy ducks at E21 compared to E27. A dual-luciferase reporter assay suggested that the ANKRD1 gene, which encodes a transcription factor, is a direct target of miR-301a-3p. Conclusions miR-301a-3p suppressed the posttranscriptional activity of ANKRD1, which is an activator of satellite cell proliferation, as determined with gain- and loss-of-function experiments. miR-301a-3p functions as an inducer of myogenesis by targeting the ANKRD1 gene in Muscovy ducks. These results provide novel insights into the early developmental process of black Muscovy breast muscles and will improve understanding of the underlying molecular mechanisms.

Penicillium strains are renowned for producing diverse secondary metabolites with unique structures and promising bioactivities. Our chemical investigations, accompanied by fermentation media optimization, of a newly isolated fungus, Penicillium shentong XL-F41, led to the isolation of twelve compounds. Among these are two novel indole terpene alkaloids, shentonins A and B (1 and 2), and a new fatty acid 3. Shentonin A (1) is distinguished by an unusual methyl modification at the oxygen atom of the typical succinimide ring, a feature not seen in the structurally similar brocaeloid D. Additionally, shentonin A (1) exhibits a cis relationship between H-3 and H-4, as opposed to the trans configuration in brocaeloid D, suggesting a divergent enzymatic ring-expansion process in their respective fungi. Both shentonins A (1) and B (2) also feature a reduction of a carbonyl to a hydroxy group within the succinimide ring. All isolated compounds were subjected to antimicrobial evaluations, and compound 12 was found to have moderate inhibitory activity against Candia albicans. Moreover, genome sequencing of Penicillium shentong XL-F41 uncovered abundant silent biosynthetic gene clusters, indicating the need for future efforts to activate these clusters and unlock the full chemical potential of the fungus.

Abstract Eukaryotic initiation translation factor 3 subunit h (EIF3H) plays critical roles in regulating translational initiation and predicts poor cancer prognosis, but the mechanism underlying EIF3H tumorigenesis remains to be further elucidated. Here, we report that EIF3H is overexpressed in colorectal cancer (CRC) and correlates with poor prognosis. Conditional Eif3h deletion suppresses colorectal tumorigenesis in AOM/DSS model. Mechanistically, EIF3H functions as a deubiquitinase for HAX1 and stabilizes HAX1 via antagonizing βTrCP-mediated ubiquitination, which enhances the interaction between RAF1, MEK1 and ERK1, thereby potentiating phosphorylation of ERK1/2. In addition, activation of Wnt/β-catenin signaling induces EIF3H expression. EIF3H/HAX1 axis promotes CRC tumorigenesis and metastasis in mouse orthotopic cancer model. Significantly, combined targeting Wnt and RAF1-ERK1/2 signaling synergistically inhibits tumor growth in EIF3H-high patient-derived xenografts. These results uncover the important roles of EIF3H in mediating CRC progression through regulating HAX1 and RAF1-ERK1/2 signaling. EIF3H represents a promising therapeutic target and prognostic marker in CRC.

Objective To explore the expression of triggering receptor expressed on myeloid cells 2 (TREM2) in high-glucose microglia and to investigate the role of TREM2 in the proliferation, migration and phagocytosis of high-glucose microglia. Methods Microglia cells were divided into control group and high-glucose treatment group(67.5 mmol/L glucose, 24 h). The microglia cells were counted and the expression of Iba1 and TREM2 was detected. TREM2 siRNA was transfected to detect the proliferation and migration of microglia. The amyloid β-peptide (Aβ) with a fluorescent tag was added to observe the phagocytosis of Aβ by microglia. Results Compared to normal microglia, the number of microglia significantly decreased after high-glucose treatment (P＜0.001), while the expression of TREM2 and Iba1 markedly increased (P＜0.001). High glucose and TREM2 did not affect the proliferation of microglia. Compared to the normal group, the migration of microglia significantly decreased after high-glucose treatment (P＜0.05) and TREM2 did not affect the migration ability of high-glucose microglia. Compared to the normal group, the phagocytosis of Aβ by microglia significantly decreased in the high-glucose treated group(P＜0.001). Furthermore, TREM2 knockdown further decreased the phagocytosis of Aβ by high-glucose microglia (P＜0.001). Conclusions The expression of TREM2 in microglia significantly increases after high-glucose treatment, which significantly affects phagocytosis of Aβ by microglia.

Background Direct oral anticoagulants (DOACs) have demonstrated clinical benefits and better patient adherence over low-molecular-weight heparin (LMWH) in treating patients with cancer-associated venous thrombosis (CAT). We aimed to compare the cost-effectiveness of DOACs against LMWH in patients with CAT from the perspective of the Hong Kong healthcare system.Methods A Markov state-transition model was performed to estimate the incremental cost-effectiveness ratio (ICER) per quality-adjusted life years (QALYs) for DOACs and LMWH in a hypothetical cohort of 10,000 patients with CAT over a 5-year lifetime horizon. The model was primarily based on the health states of no event, recurrent venous thromboembolism, bleeding, and death. Transition probabilities, relative risks, and utilities were derived from the literature. Resource cost data were obtained from the Hong Kong Hospital Authority. Deterministic and probabilistic sensitivity analyses tested the robustness of the results.Results Relative to LMWH, DOACs were associated with increased QALYs (1.52 versus 1.50) at a lower medical cost of USD 2,232 versus 8,224 in five years. The cost of LMWH was the main contributor to the outcome. Out of 10,000 simulated cases, DOACs were dominant in 15.8% and cost-effective in 42.1%, at the willingness-to-pay threshold of USD 148,392 per additional QALY.Conclusions DOACs were associated with greater QALY improvements and lower overall costs compared to LMWH. Accounting for uncertainty, DOACs were between cost-effective and dominant in 57.9% of cases. DOACs are a cost-effective alternative to LMWH in the management of CAT in Hong Kong.

We present a systematic MEMS structural design approach via a "trial-and-error"learning process by using the deep reinforcement learning framework. This scheme incorporates the feedback from each "trial"to obtain sophisticated strategies for MEMS design optimizations. Disk-shaped MEMS resonators are selected as case studies and three remarkable advancements have been realized: 1) accurate overall performance predictions (97.9%) via supervised learning models; 2) efficient MEMS structural optimizations to guarantee targeted structural properties with an excellent generation accuracy of 97.7%; and 3) superior design explorations to achieve one order of magnitude performance enhancement than the training dataset. As such, the proposed scheme could facilitate a wide spectrum of MEMS applications with this data-driven inverse design methodology.

This work presents an air-coupled piezoelectric micromachined ultrasonic transducer (pMUT) with high transmitting acoustic pressure by using sputtered potassium sodium niobate (K,Na)NbO3 (KNN) thin film with a high piezoelectric coefficient (e31 ∼ 8-10 C/m2) and low dielectric constant (ϵr ∼ 260-300) for the first time. The fabricated KNN pMUT with a resonant frequency at 104.5 kHz has been tested to exhibit unprecedented results: (1) high sound pressure level (SPL) of 109 dB/V at a distance of 10 cm, which is 8 times higher than that of AlN-based pMUTs at a similar frequency; (2) low-voltage operation of only 4 volts peak-to-peak amplitude (Vp-p); and (3) good receiving sensitivity. As such, this work presents a new class of high-SPL and low-driving-voltage pMUTs for potential applications in various fields, including consumer electronics, such as but not limited to haptic feedback, loudspeaker, and AR/VR systems.

This paper reports a low-frequency piezoelectric micromachined ultrasonic transducer (pMUT) with a small attenuation coefficient to realize the long-distance range finding applications in air. Pulse-detection measurements of one pair of pMUT devices show a >6-meter traveling distance in air under a 37.32 kHz driving frequency. As an example, two pMUT chips are mounted on two drones as the transceiver and receiver, respectively. Measurements of the separation distance are conducted based on the time-of-flight (ToF) principle with up to 32 fps (frames per second) for real-time detections. This demo of drone-mounted pMUT system illustrates the advantages of pMUT in terms of compactness and low power consumption for applications in drones including obstacle avoidance, inter collision prevention, aerial coordination, and acoustic-based vision.

This work reports an engineered platform for the non-contact haptic stimulation on human skins by means of an array of piezoelectric micromachined ultrasonic transducer (pMUT) via the beamforming scheme. Compared to the state-of-art reports, three distinctive achievements have been demonstrated: (1) individual single pMUT unit based on lithium niobate (LN) with measured high SPL (sound pressure level) of 133 dB at 2 mm away; (2) a beamforming scheme simulated and experimentally proved to generate ∼2.3x higher pressure near the focal point; and (3) the combination of auto-positioning and haptic stimulations on volunteers with the smallest reported physical device size to achieve haptic sensations. As such, this work could have practical applications in the broad areas to stimulate haptic sensations, such as AR (Augmented Reality), VR (Virtual Reality), and robotics.

This paper presents a mid-air thermal interface enabled by a piezoelectric micromachined ultrasonic transducer (pMUT) array. The two-stage thermal actuating process consists of an ultrasound-transmission process via a pMUT array and an ultrasound-absorption process via porous fabric. The pMUT design employs sputtered potassium sodium niobate (K, Na)NbO3 (KNN) thin film with a high piezoelectric coefficient ( 31 ~ 8-10 C/m2) as piezoelectric layer for enhanced acoustic pressure. Testing results show that the prototype pMUT array has a resonant frequency around 97.6 kHz, and it can generate 1970 Pa of focal pressure at 15 mm away under the 10.6 Vp-p excitation. As a result, fabric temperature in the central focal area can rise from 24.2°C to 31.7°C after 320 seconds with an average temperature variation rate of 0.023°C /s. Moreover, thermal sensations on the human palms have been realized by the heat conduction through the fabric-skin contact. As such, this work highlights the promising application of pMUT array with high acoustic pressure for human-machine interface, particularly mid-air thermal display.

BackgroundThe protective effectiveness provided by naturally acquired immunity against SARS-CoV-2 reinfection remain controversial.ObjectiveTo systematically evaluate the protective effect of natural immunity against subsequent SARS-CoV-2 infection with different variants.MethodsWe searched for related studies published in seven databases before March 5, 2023. Eligible studies included in the analysis reported the risk of subsequent infection for groups with or without a prior SARS-CoV-2 infection. The primary outcome was the overall pooled incidence rate ratio (IRR) of SARS-CoV-2 reinfection/infection between the two groups. We also focused on the protective effectiveness of natural immunity against reinfection/infection with different SARS-CoV-2 variants. We used a random-effects model to pool the data, and obtained the bias-adjusted results using the trim-and-fill method. Meta-regression and subgroup analyses were conducted to explore the sources of heterogeneity. Sensitivity analysis was performed by excluding included studies one by one to evaluate the stability of the results.ResultsWe identified 40 eligible articles including more than 20 million individuals without the history of SARS-CoV-2 vaccination. The bias-adjusted efficacy of naturally acquired antibodies against reinfection was estimated at 65% (pooled IRR = 0.35, 95% CI = 0.26–0.47), with higher efficacy against symptomatic COVID-19 cases (pooled IRR = 0.15, 95% CI = 0.08–0.26) than asymptomatic infection (pooled IRR = 0.40, 95% CI = 0.29–0.54). Meta-regression revealed that SARS-CoV-2 variant was a statistically significant effect modifier, which explaining 46.40% of the variation in IRRs. For different SARS-CoV-2 variant, the pooled IRRs for the Alpha (pooled IRR = 0.11, 95% CI = 0.06–0.19), Delta (pooled IRR = 0.19, 95% CI = 0.15–0.24) and Omicron (pooled IRR = 0.61, 95% CI = 0.42–0.87) variant were higher and higher. In other subgroup analyses, the pooled IRRs of SARS-CoV-2 infection were statistically various in different countries, publication year and the inclusion end time of population, with a significant difference (p = 0.02, p

BackgroundTo date, more than 770 million individuals have become coronavirus disease 2019 (COVID-19) convalescents worldwide. Emerging evidence highlights the influence of COVID-19 on the oral microbiome during both acute and convalescent disease phases. Front-line healthcare workers are at an elevated risk of exposure to viral infections, and the effects of COVID-19 on their oral microbiome remain relatively unexplored.MethodsOropharyngeal swab specimens, collected one month after a negative COVID-19 test from a cohort comprising 55 healthcare workers, underwent 16S rRNA sequencing. We conducted a comparative analysis between this post-COVID-19 cohort and the pre-infection dataset from the same participants. Community composition analysis, indicator species analysis, alpha diversity assessment, beta diversity exploration, and functional prediction were evaluated.ResultsThe Shannon and Simpson indexes of the oral microbial community declined significantly in the post-COVID-19 group when compared with the pre-infection cohort. Moreover, there was clear intergroup clustering between the two groups. In the post-COVID-19 group, the phylum Firmicutes showed a significant increase. Further, there were clear differences in relative abundance of several bacterial genera in contrast with the pre-infection group, including Streptococcus, Gemella, Granulicatella, Capnocytophaga, Leptotrichia, Fusobacterium, and Prevotella. We identified Gemella enrichment in the post-COVID-19 group, potentially serving as a recovery period performance indicator. Functional prediction revealed lipopolysaccharide biosynthesis downregulation in the post-COVID-19 group, an outcome with host inflammatory response modulation and innate defence mechanism implications.ConclusionDuring the recovery phase of COVID-19, the oral microbiome diversity of front-line healthcare workers failed to fully return to its pre-infection state. Despite the negative COVID-19 test result one month later, notable disparities persisted in the composition and functional attributes of the oral microbiota.