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1.
China CDC Wkly ; 6(15): 305-311, 2024 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-38736994

RESUMEN

What is already known about this topic?: Individuals who initially contract severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) lack significant mixed immunity. Therefore, it is crucial to monitor the clinical characteristics and associated factors of these individuals in order to inform policy-making. What is added by this report?: The common symptoms reported were fever, cough, and sore throat. Reinfections and receiving four vaccination doses within a 6-month period were found to be associated with a shorter duration of virus shedding, decreased hospitalization rate, and reduced risk of pneumonia. Individuals aged 60 years and older, as well as those with underlying medical conditions, had a higher risk of developing pneumonia. What are the implication for public health practices?: Online surveys conducted through social media platforms have the potential to complement disease surveillance and data collection efforts. In terms of vaccination prioritization, it is recommended to prioritize older individuals and those with underlying diseases.

2.
Cryobiology ; 115: 104895, 2024 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-38616031

RESUMEN

The study is devoted to the effect of lowered resuscitation temperature (26 °C) on cryopreserved porcine adrenal glands functional activity in vitro and in vivo under xenotransplantation. The adrenals were collected from newborn pigs, cryopreserved with 5 % DMSO at a rate of 1 °C/min, resuscitated at 26 or 37 °C for 48 h (5 % CO2, DMEM), embedded into small intestinal submucosa, and transplanted to bilaterally adrenalectomized rats. It has been shown that the glands resuscitated at 26 °C have suppressed free-radical processes and can produce cortisol and aldosterone in vitro, and may lead to elevated blood levels of these hormones. Moreover, the adrenal grafts maintain blood glucose levels and promote the formation of glycogen stores. Thus, the resuscitation at 26 °C can improve the quality of grafts and favor the introduction and application of the cryopreserved organs and tissues for transplantation in clinical and experimental practice.

4.
Food Chem ; 449: 139231, 2024 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-38579654

RESUMEN

Pyrethroids are widely used insecticides worldwide, while their on-site and rapid detection still faces technological challenges. Herein, an innovative detection mechanism was designed for deltamethrin, a typical kind of type II pyrethroids, based on a dual-emitting fluoroprobe consisting of NH2-SiQDs and Eu3+. Deltamethrin can rapidly hydrolyze into 3-phenoxybenzaldehyde (3-PBD) and react specifically with fluoroprobe, causing fluorescence quenching of SiQDs while maintaining the fluorescent stability of Eu3+. Building upon the above fluorescence-responsive principle, SiQDs@Eu3+ provided satisfactorily dual-emitting signals, realizing the highly-selective and sensitive detection of deltamethrin. Correlation between the surface structure of SiQDs and their absorption spectra was in-depth unraveled by TD-DFT calculation and FT-IR analysis. As for the analytical performance, the recovery and LOD of deltamethrin in lettuce, provided by SiQDs@Eu3+, were comparable or even superior over conventional chromatographic analysis. Meanwhile, an innovative smartphone-based optical device was developed, which greatly decreased errors caused by the previously reported smartphone-based fluorescence detection.


Asunto(s)
Contaminación de Alimentos , Insecticidas , Nitrilos , Piretrinas , Teléfono Inteligente , Piretrinas/química , Piretrinas/análisis , Nitrilos/química , Insecticidas/química , Insecticidas/análisis , Contaminación de Alimentos/análisis , Lactuca/química , Espectrometría de Fluorescencia , Fluorescencia , Colorantes Fluorescentes/química , Límite de Detección
5.
Ann Anat ; 254: 152259, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38492655

RESUMEN

BACKGROUND: Osteoarthritis (OA) is a chronic and complicated degenerative disorder of joints, including several phenotypes. Type 2 diabetes mellitus (T2DM) is one of the major causes of OA. However, few studies on the mechanical behavior of diabetic cartilages have been conducted. METHODS: This study evaluated the microstructural, compositional, and mechanical properties of healthy and diabetic rat cartilages using scanning electronic microscopy, X-ray energy spectroscopy, histology staining, and microindentation tests. RESULTS: Our results indicated that the diabetic cartilages had a significantly higher elastic modulus and similar permeability (95%CI: 3.72-8.56 MPa and 3.16×10-6-1.83×10-5 mm4/N·s) compared to the healthy cartilages (95%CI: 0.741-3.58 MPa and 3.15×10-6-1.14×10-5 mm4/N·s). Their stress relaxation behaviors were similar regardless of the loading rate except for the stretching parameter under the fast loading. Furthermore, the stress relaxation behaviors of the diabetic cartilages were significantly affected by the loading rate, especially the equilibrium force ratio and time constant. These mechanical outcomes could be attributed to the increase of fibril diameters and calcium aggregation in the cartilage. CONCLUSIONS: This study deepens our understanding of how T2DM might facilitate OA in cartilages, which could contribute to the development of more scientific diagnosis and therapies for patients with diabetes.


Asunto(s)
Diabetes Mellitus Experimental , Diabetes Mellitus Tipo 2 , Animales , Diabetes Mellitus Tipo 2/patología , Ratas , Diabetes Mellitus Experimental/patología , Masculino , Cartílago Articular/patología , Cartílago Articular/ultraestructura , Fenómenos Biomecánicos , Ratas Sprague-Dawley , Módulo de Elasticidad , Microscopía Electrónica de Rastreo , Estrés Mecánico , Osteoartritis/patología
6.
J Hazard Mater ; 469: 134045, 2024 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-38492388

RESUMEN

Tetracycline hydrochloride (TCH), a prevalent antibiotic in aquaculture for treating bacterial infections, poses challenges for on-site detection. This study employed the reversed-phase microemulsion method to synthesize a uniform nano metal-organic framework (MOF) material, europium-benzene-p-dicarboxylic acid (Eu-BDC), doped with Tb3+ to form a dual-emission fluorescence probe. By leveraging the combined a-photoinduced electron-transfer (a-PET) and inner filter effect (IFE) mechanisms, high-sensitivity TCH detection in Carassius auratus and Ruditapes philippinarum was achieved. The detection range for TCH is 0.380-75 µM, with a low limit of detection (LOD) at 0.115 µM. Upon TCH binding, Eu-BDC fluorescence rapidly decreased, while Tb3+ fluorescence remained constant, establishing a ratiometric fluorescence change. Investigation into the TCH quenching mechanism on Eu-BDC was conducted using time-dependent density functional theory (TD-DFT) calculations and fluorescence quenching kinetic equations, suggesting a mixed quenching mechanism. Furthermore, a novel photoelectric conversion fluorescence detection device (FL-2) was developed and evaluated in conjunction with high-performance liquid chromatography-diode-array detection (HPLC-DAD). This is the first dedicated fluorescence device for TCH detection, showcasing superior photoelectric conversion performance and stability that reduces experimental errors associated with smartphone photography methods, presenting a promising avenue for on-site rapid TCH detection.


Asunto(s)
Estructuras Metalorgánicas , Tetraciclina , Animales , Espectrometría de Fluorescencia/métodos , Antibacterianos , Europio , Colorantes Fluorescentes , Agua Dulce
8.
Hum Vaccin Immunother ; 20(1): 2330163, 2024 Dec 31.
Artículo en Inglés | MEDLINE | ID: mdl-38544389

RESUMEN

The Enterovirus A71 (EV-A71) vaccine was introduced in China in December 2015 as a preventive measure against hand, foot, and mouth disease (HFMD) caused by EV-A71. However, the effectiveness of the vaccine (VE) in real-world settings needs to be evaluated. We conducted a test-negative case-control study to assess the effectiveness of EV-A71 vaccines in preventing EV-A71-associated HFMD. Children aged 6-71 months with HFMD were enrolled as participants. The case group comprised those who tested positive for EV-A71, while the control group comprised those who tested negative for EV-A71. To estimate VE, a logistic regression model was employed, adjusting for potential confounders including age, gender, and clinical severity. In total, 3223 children aged 6 to 71 months were included in the study, with 162 in the case group and 3061 in the control group. The proportion of children who received EV-A71 vaccination was significantly lower in the case group compared to the control group (p < .001). The overall VEadj was estimated to be 90.8%. The VEadj estimates for partially and fully vaccinated children were 90.1% and 90.9%, respectively. Stratified by age group, the VEadj estimates were 88.7% for 6 to 35-month-olds and 95.5% for 36 to 71-month-olds. Regarding disease severity, the VEadj estimates were 86.3% for mild cases and 100% for severe cases. Sensitivity analysis showed minimal changes in the VE point estimates, with most changing by no more than 1% point. Our study demonstrates a high level of vaccine effectiveness against EV-A71-HFMD, especially in severe cases. Active promotion of EV-A71 vaccination is an effective strategy in preventing EV-A71 infections.


Asunto(s)
Enterovirus Humano A , Infecciones por Enterovirus , Enterovirus , Enfermedad de Boca, Mano y Pie , Niño , Humanos , Enfermedad de Boca, Mano y Pie/prevención & control , Estudios de Casos y Controles , Vacunas de Productos Inactivados , China/epidemiología , Antígenos Virales
9.
BMC Infect Dis ; 24(1): 294, 2024 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-38448822

RESUMEN

BACKGROUND: The latent and incubation periods characterize the transmission of infectious viruses and are the basis for the development of outbreak prevention and control strategies. However, systematic studies on the latent period and associated factors with the incubation period for SAS-CoV-2 variants are still lacking. We inferred the two durations of Delta, BA.1, and BA.2 cases and analyzed the associated factors. METHODS: The Delta, BA.1, and BA.2 (and its lineages BA.2.2 and BA.2.76) cases with clear transmission chains and infectors from 10 local SAS-CoV-2 epidemics in China were enrolled. The latent and incubation periods were fitted by the Gamma distribution, and associated factors were analyzed using the accelerated failure time model. RESULTS: The mean latent period for 672 Delta, 208 BA.1, and 677 BA.2 cases was 4.40 (95%CI: 4.24 ~ 4.63), 2.50 (95%CI: 2.27 ~ 2.76), and 2.58 (95%CI: 2.48 ~ 2.69) days, respectively, with 85.65% (95%CI: 83.40 ~ 87.77%), 97.80% (95%CI: 96.35 ~ 98.89%), and 98.87% (95%CI: 98.40 ~ 99.27%) of them starting to shed viruses within 7 days after exposure. In 405 Delta, 75 BA.1, and 345 BA.2 symptomatic cases, the mean latent period was 0.76, 1.07, and 0.79 days shorter than the mean incubation period [5.04 (95%CI: 4.83 ~ 5.33), 3.42 (95%CI: 3.00 ~ 3.89), and 3.39 (95%CI: 3.24 ~ 3.55) days], respectively. No significant difference was observed in the two durations between BA.1 and BA.2 cases. After controlling for the sex, clinical severity, vaccination history, number of infectors, the length of exposure window and shedding window, the latent period [Delta: exp(ß) = 0.81, 95%CI: 0.66 ~ 0.98, p = 0.034; Omicron: exp(ß) = 0.82, 95%CI: 0.71 ~ 0.94, p = 0.004] and incubation period [Delta: exp(ß) = 0.69, 95%CI: 0.55 ~ 0.86, p < 0.001; Omicron: exp(ß) = 0.83, 95%CI: 0.72 ~ 0.96, p = 0.013] were significantly shorter in 18 ~ 49 years but did not change significantly in ≥ 50 years compared with 0 ~ 17 years. CONCLUSION: Pre-symptomatic transmission can occur in Delta, BA.1, and BA.2 cases. The latent and incubation periods between BA.1 and BA.2 were similar but shorter compared with Delta. Age may be associated with the latent and incubation periods of SARS-CoV-2.


Asunto(s)
Epidemias , Periodo de Incubación de Enfermedades Infecciosas , Humanos , Estudios Transversales , China/epidemiología , Brotes de Enfermedades
10.
Artículo en Inglés | MEDLINE | ID: mdl-38372937

RESUMEN

The increasing infection and drug resistance frequency has encouraged the exploration of new and effective anti-Candida albicans agents. In this study, CT-K3K7, a scorpion antimicrobial peptide derivative, effectively inhibit the growth of C. albicans. CT-K3K7 killed C. albicans cells in a dose-dependent manner, mainly by damaging the plasma membrane. CT-K3K7 could also disrupt the nucleus and interact with nucleic acid. Moreover, CT-K3K7 induced C. albicans cells necrosis via a reactive oxygen species (ROS)-related pathway. Furthermore, CT-K3K7 inhibited the hyphal and biofilm formation of C. albicans. In the mouse skin subcutaneous infection model, CT-K3K7 significantly prevented skin abscess formation and reduced the number of C. albicans cells recovered from the infection area. Taken together, CT-K3K7 has the potential to be a therapeutic for C. albicans skin infections.

11.
Artículo en Inglés | MEDLINE | ID: mdl-38381354

RESUMEN

OBJECTIVES: The concurrent impact of COVID-19 and influenza on disease burden is a topic of great concern. This discussion delves into the epidemiological characteristics of seasonal influenza activity in Shanghai within the context of the SARS-CoV-2 epidemic. METHODS: From 2017 to 2023, a total of 11,081 patients having influenza-like illness (ILI) were included in this study for influenza virus detection. Reverse transcription polymerase chain reaction (RT-PCR) assays were conducted according to standardised protocols to identify the types and subtypes of influenza viruses. The positivity rate of the influenza virus among the sampled ILI cases served as a surrogate measure for estimating various influenza seasonal characteristics, such as periodicity, duration, peak occurrences, and the prevalent subtypes or lineages. Epidemiological aspects across different years and age groups were subjected to comprehensive analysis. For categorical variables, the Chi-square test or Fisher's exact test was employed, as deemed appropriate. RESULTS: A total of 1553 (14.0%) tested positive for influenza virus pathogens. The highest positivity rate for influenza was observed in adults aged 25-59 years (18.8%), while the lowest rate was recorded in children under 5 years (3.8%). The influenza circulation patterns in Shanghai were characterised: (1) 2 years exhibited semiannual periodicity (2017-2018, 2022-2023); (2) 3 years displayed annual periodicity (2018-2019, 2019-2020, and 2021-2022); and (3) during 2020-2021, epidemic periodicities of seasonal influenza viruses disappeared. In terms of influenza subtypes, four subtypes were identified during 2017-2018. In 2018-2019 and 2019-2020, A/H3N2, A/H1N1, and B/Victoria were circulating. Notably, one case of B/Victoria was detected in 2020-2021. The epidemic period of 2021-2022 was attributed to B/Victoria, and during 2022-2023, the influenza A virus was the dominant circulating strain. CONCLUSIONS: The seasonal epidemic period and the predominant subtype/lineage of influenza viruses around the SARS-CoV-2 epidemic period in Shanghai city are complex. This underscores the necessity for vigilant influenza control strategies amidst the backdrop of other respiratory virus pandemics.

12.
Toxicon ; 238: 107593, 2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-38163461

RESUMEN

As an alternative class of antimicrobial agents, antimicrobial peptides (AMPs) have gained significant attention. In this study, K1K8, a scorpion AMP derivative, showed effective activity against Candida albicans including clinically resistant strains. K1K8 killed C. albicans cells mainly by damaging the cell membrane and inducing necrosis via an ROS-related pathway. K1K8 could also interact with DNA after damaging the nuclear envelope. Moreover, K1K8 inhibited hyphal development and biofilm formation of C. albicans in a dose-dependent manner. In the mouse skin infection model, K1K8 significantly decreased the counts of C. albicans cells in the infection area. Overall, K1K8 is a potential anti-infective agent against skin infections caused by C. albicans.


Asunto(s)
Antiinfecciosos , Antifúngicos , Animales , Ratones , Antifúngicos/farmacología , Candida albicans , Escorpiones , Péptidos/farmacología , Antiinfecciosos/farmacología , Pruebas de Sensibilidad Microbiana
13.
Influenza Other Respir Viruses ; 17(11): e13212, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37964991

RESUMEN

Background: A viral infection can modify the risk to subsequent viral infections via cross-protective immunity, increased immunopathology, or disease-driven behavioral change. There is limited understanding of virus-virus interactions due to lack of long-term population-level data. Methods: Our study leverages passive surveillance data of 10 human acute respiratory viruses from Beijing, Chongqing, Guangzhou, and Shanghai collected during 2009 to 2019: influenza A and B viruses; respiratory syncytial virus A and B; human parainfluenza virus (HPIV), adenovirus, metapneumovirus (HMPV), coronavirus, bocavirus (HBoV), and rhinovirus (HRV). We used a multivariate Bayesian hierarchical model to evaluate correlations in monthly prevalence of test-positive samples between virus pairs, adjusting for potential confounders. Results: Of 101,643 lab-tested patients, 33,650 tested positive for any acute respiratory virus, and 4,113 were co-infected with multiple viruses. After adjusting for intrinsic seasonality, long-term trends and multiple comparisons, Bayesian multivariate modeling found positive correlations for HPIV/HRV in all cities and for HBoV/HRV and HBoV/HMPV in three cities. Models restricted to children further revealed statistically significant associations for another ten pairs in three of the four cities. In contrast, no consistent correlation across cities was found among adults. Most virus-virus interactions exhibited substantial spatial heterogeneity. Conclusions: There was strong evidence for interactions among common respiratory viruses in highly populated urban settings. Consistent positive interactions across multiple cities were observed in viruses known to typically infect children. Future intervention programs such as development of combination vaccines may consider spatially consistent virus-virus interactions for more effective control.


Asunto(s)
Virus Sincitial Respiratorio Humano , Infecciones del Sistema Respiratorio , Virosis , Virus , Niño , Adulto , Humanos , Lactante , Beijing/epidemiología , Infecciones del Sistema Respiratorio/epidemiología , Teorema de Bayes , China/epidemiología , Virus/genética , Virosis/epidemiología
14.
Quant Imaging Med Surg ; 13(10): 6446-6455, 2023 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-37869327

RESUMEN

Background: Ultrasonography has been applied as an alternative method in the assessment of temporomandibular joint (TMJ) pathology including anterior disc displacement (ADD). However, a concrete screening or diagnostic method which is feasible in clinical practice has not yet been established. The study aimed to establish a quantitative ultrasonographic method and determine its diagnostic efficacy for ADD of the TMJ. Methods: A total of 75 joints were allocated to either the normal disc position (NDP) group or the ADD group using magnetic resonance imaging (MRI) as the reference standard. Longitudinal scans of the lateral articular compartment were obtained by a 14-MHz L-shaped linear array transducer. The width of the lateral joint space (LJS), the upper lateral joint space (ULJS), and the lower lateral joint space (LLJS), as well as the position of the lateral articular disc edge (ADE), were investigated by stepwise logistic regression analysis to identify significant indicators of ADD and to build a diagnostic model. Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and diagnostic accuracy were computed at the optimal cut-off value. Results: MRI detected 25 joints in the NDP group and 50 joints in the ADD group. Correlation analysis indicated that all 4 variables were associated with ADD. With the best performance of the area under the receiver operating characteristic (ROC) curve (AUC) of 0.939, LJS and ULJS were identified as predictors of ADD and subsequently adopted to build a diagnostic model by stepwise logistic regression. The optimal cut-off value of the 2-variable regression model for diagnosing ADD was 0.800, with a sensitivity of 82%, specificity of 96%, PPV of 97.6%, NPV of 72.7%, and an accuracy of 86.7%. Conclusions: The quantitative ultrasonographic diagnostic method showed promising diagnostic efficacy. It has the potential to be used for ADD screening in future clinical practice.

15.
Arch Microbiol ; 205(12): 362, 2023 Oct 31.
Artículo en Inglés | MEDLINE | ID: mdl-37904066

RESUMEN

Salmonella, a Gram-negative bacterium that infects humans and animals, causes diseases ranging from gastroenteritis to severe systemic infections. Here, we discuss various strategies used by Salmonella against host cell defenses. Epithelial cell invasion largely depends on a Salmonella pathogenicity island (SPI)-1-encoded type 3 secretion system, a molecular syringe for injecting effector proteins directly into host cells. The internalization of Salmonella into macrophages is primarily driven by phagocytosis. After entering the host cell cytoplasm, Salmonella releases many effectors to achieve intracellular survival and replication using several secretion systems, primarily an SPI-2-encoded type 3 secretion system. Salmonella-containing vacuoles protect Salmonella from contacting bactericidal substances in epithelial cells and macrophages. Salmonella modulates the immunity, metabolism, cell cycle, and viability of host cells to expand its survival in the host, and the intracellular environment of Salmonella-infected cells promotes its virulence. This review provides insights into how Salmonella subverts host cell defenses for survival.


Asunto(s)
Salmonella enterica , Sistemas de Secreción Tipo III , Animales , Humanos , Sistemas de Secreción Tipo III/genética , Sistemas de Secreción Tipo III/metabolismo , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Salmonella typhimurium/metabolismo , Salmonella enterica/metabolismo , Virulencia
16.
Entropy (Basel) ; 25(9)2023 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-37761657

RESUMEN

A vehicular network embodies a specialized variant of wireless network systems, characterized by its capability to facilitate inter-vehicular communication and connectivity with the encompassing infrastructure. With the rapid development of wireless communication technology, high-speed and reliable communication has become increasingly important in vehicular networks. It has been demonstrated that orthogonal time frequency space (OTFS) modulation proves effective in addressing the challenges posed by high-mobility environments, as it transforms the time-varying channels into the delay-Doppler domain. Motivated by this, in this paper, we focus on the theme of integrated sensing and communication (ISAC)-assisted OTFS receiver design, which aims to perform sensing channel estimation and communication symbol detection. Specifically, the estimation of the sensing channel is accomplished through the utilization of a deep residual denoising network (DRDN), while the communication symbol detection is performed by orthogonal approximate message passing (OAMP) processing. The numerical results demonstrate that the proposed ISAC system exhibits superior performance and robustness compared to traditional methods, with a lower complexity as well. The proposed system has great potential for future applications in wireless communication systems, especially in challenging scenarios with high mobility and interference.

17.
Research (Wash D C) ; 6: 0237, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37746657

RESUMEN

The influence of a mechanical structure's volume increment on the volume power density (VPD) of triboelectric nanogenerators (TENGs) is often neglected when considering surface charge density and surface power density. This paper aims to address this gap by introducing a standardized VPD metric for a more comprehensive evaluation of TENG performance. The study specifically focuses on 2 frequency-up mechanisms, namely, the integration of planetary gears (PG-TENG) and the implementation of a double-cantilever structure (DC-TENG), to investigate their impact on VPD. The study reveals that the PG-TENG achieves the highest volume average power density, measuring at 0.92 W/m3. This value surpasses the DC-TENG by 1.26 times and the counterpart TENG by a magnitude of 69.9 times. Additionally, the PG-TENG demonstrates superior average power output. These findings introduce a new approach for enhancing TENGs by incorporating frequency-up mechanisms, and highlight the importance of VPD as a key performance metric for evaluating TENGs.

18.
Nat Commun ; 14(1): 5270, 2023 08 29.
Artículo en Inglés | MEDLINE | ID: mdl-37644012

RESUMEN

Targeted public health interventions for an emerging epidemic are essential for preventing pandemics. During 2020-2022, China invested significant efforts in strict zero-COVID measures to contain outbreaks of varying scales caused by different SARS-CoV-2 variants. Based on a multi-year empirical dataset containing 131 outbreaks observed in China from April 2020 to May 2022 and simulated scenarios, we ranked the relative intervention effectiveness by their reduction in instantaneous reproduction number. We found that, overall, social distancing measures (38% reduction, 95% prediction interval 31-45%), face masks (30%, 17-42%) and close contact tracing (28%, 24-31%) were most effective. Contact tracing was crucial in containing outbreaks during the initial phases, while social distancing measures became increasingly prominent as the spread persisted. In addition, infections with higher transmissibility and a shorter latent period posed more challenges for these measures. Our findings provide quantitative evidence on the effects of public-health measures for zeroing out emerging contagions in different contexts.


Asunto(s)
COVID-19 , Salud Pública , Humanos , SARS-CoV-2/genética , COVID-19/epidemiología , COVID-19/prevención & control , Pandemias/prevención & control
19.
Adv Sci (Weinh) ; 10(26): e2302443, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37409423

RESUMEN

The accomplishment of condition monitoring and intelligent maintenance for cantilever structure-based energy harvesting devices remains a challenge. Here, to tackle the problems, a novel cantilever-structure freestanding triboelectric nanogenerator (CSF-TENG) is proposed, which can capture ambient energy or transmit sensory information. First, with and without a crack in cantilevers, the simulations are carried out. According to simulation results, the maximum change ratios of natural frequency and amplitude are 1.1% and 2.2%, causing difficulties in identifying defects by these variations. Thus, based on Gramian angular field and convolutional neural network, a defect detection model is established to achieve the condition monitoring of the CSF-TENG, and the experimental result manifests that the accuracy of the model is 99.2%. Besides, the relation between the deflection of cantilevers and the output voltages of the CSF-TENG is first built, and then the defect identification digital twin system is successfully created. Consequently, the system is capable of duplicating the operation of the CSF-TENG in a real environment, and displaying defect recognition results, so the intelligent maintenance of the CSF-TENG can be realized.

20.
Vaccines (Basel) ; 11(7)2023 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-37514962

RESUMEN

Reinfection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants due to immune escape is challenging for the global response to the pandemic. We estimated the Omicron reinfection prevalence among people who had a previous SARS-CoV-2 infection in Shanghai, China. We conducted a telephone survey in December 2022 with those who had previously been infected with Omicron between March and May 2022. Information on their demographics, coronavirus disease 2019 (COVID-19) testing, and vaccination history was collected. The overall and subgroup reinfection rates were estimated and compared. Among the 1981 respondents who were infected between March and May 2022, 260 had positive nucleic acid or rapid antigen tests in December 2022, with an estimated reinfection rate of 13.1% (95% confidence interval [95% CI]: 11.6-14.6). The reinfection rate for those who had a booster vaccination was 11.4% (95% CI: 9.2-13.7), which was significantly lower than that for those with an incomplete vaccination series (15.2%, 95% CI: 12.3-18.1) (adjusted odds ratio [aOR]: 0.579; 95% CI: 0.412-0.813). Reinfection with the Omicron variant was lower among individuals with a previous SARS-CoV-2 infection and those who had a booster vaccination, suggesting that hybrid immunity may offer protection against reinfection with Omicron sublineages.

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