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1.
Cell ; 181(5): 997-1003.e9, 2020 05 28.
Artículo en Inglés | MEDLINE | ID: mdl-32359424

RESUMEN

Coronavirus disease 2019 (COVID-19) is caused by SARS-CoV-2 infection and was first reported in central China in December 2019. Extensive molecular surveillance in Guangdong, China's most populous province, during early 2020 resulted in 1,388 reported RNA-positive cases from 1.6 million tests. In order to understand the molecular epidemiology and genetic diversity of SARS-CoV-2 in China, we generated 53 genomes from infected individuals in Guangdong using a combination of metagenomic sequencing and tiling amplicon approaches. Combined epidemiological and phylogenetic analyses indicate multiple independent introductions to Guangdong, although phylogenetic clustering is uncertain because of low virus genetic variation early in the pandemic. Our results illustrate how the timing, size, and duration of putative local transmission chains were constrained by national travel restrictions and by the province's large-scale intensive surveillance and intervention measures. Despite these successes, COVID-19 surveillance in Guangdong is still required, because the number of cases imported from other countries has increased.


Asunto(s)
Betacoronavirus/genética , Infecciones por Coronavirus/epidemiología , Neumonía Viral/epidemiología , Teorema de Bayes , COVID-19 , China/epidemiología , Infecciones por Coronavirus/virología , Monitoreo Epidemiológico , Humanos , Funciones de Verosimilitud , Pandemias , Neumonía Viral/virología , SARS-CoV-2 , Viaje
2.
Proc Natl Acad Sci U S A ; 120(17): e2218623120, 2023 04 25.
Artículo en Inglés | MEDLINE | ID: mdl-37068248

RESUMEN

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spreads efficiently by spike-mediated, direct cell-to-cell transmission. However, the underlying mechanism is poorly understood. Herein, we demonstrate that the tight junction protein occludin (OCLN) is critical to this process. SARS-CoV-2 infection alters OCLN distribution and expression and causes syncytium formation that leads to viral spread. OCLN knockdown fails to alter SARS-CoV-2 binding but significantly lowers internalization, syncytium formation, and transmission. OCLN overexpression also has no effect on virus binding but enhances virus internalization, cell-to-cell transmission, and replication. OCLN directly interacts with the SARS-CoV-2 spike, and the endosomal entry pathway is involved in OCLN-mediated cell-to-cell fusion rather than in the cell surface entry pathway. All SARS-CoV-2 strains tested (prototypic, alpha, beta, gamma, delta, kappa, and omicron) are dependent on OCLN for cell-to-cell transmission, although the extent of syncytium formation differs between strains. We conclude that SARS-CoV-2 utilizes OCLN as an internalization factor for cell-to-cell transmission.


Asunto(s)
COVID-19 , Ocludina , Proteínas de Uniones Estrechas , Internalización del Virus , Humanos , Ocludina/genética , Ocludina/metabolismo , SARS-CoV-2/metabolismo , Glicoproteína de la Espiga del Coronavirus/genética
3.
J Immunol ; 211(8): 1187-1194, 2023 10 15.
Artículo en Inglés | MEDLINE | ID: mdl-37782856

RESUMEN

Pigs play an important role in influenza A virus (IAV) epidemiology because they support replication of human, avian, and swine origin viruses and act as an IAV reservoir for pigs and other species, including humans. Moreover, novel IAVs with human pandemic potential may be generated in pigs. To minimize the threat of IAVs to human and swine health, it is crucial to understand host defense mechanisms that restrict viral replication and pathology in pigs. In this article, we review IAV strains circulating in the North American swine population, as well as porcine innate and acquired immune responses to IAV, including recent advances achieved through immunological tools developed specifically for swine. Furthermore, we highlight unique aspects of the porcine pulmonary immune system, which warrant consideration when developing vaccines and therapeutics to limit IAV in swine or when using pigs to model human IAV infections.


Asunto(s)
Enfermedades Transmisibles , Virus de la Influenza A , Gripe Humana , Infecciones por Orthomyxoviridae , Animales , Humanos , Porcinos , Cola (estructura animal)
4.
J Am Chem Soc ; 146(18): 12565-12576, 2024 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-38661569

RESUMEN

Protein@metal-organic frameworks (P@MOFs) prepared by coprecipitation of protein, metal ions, and organic ligands represent an effective method for protein stabilization with a wide spectrum of applications. However, the formation mechanism of P@MOFs via the coprecipitation process and the reason why proteins can retain their biological activity in the frameworks with highly concentrated metal ions remain unsettled. Here, by a combined methodology of single molecule localization microscopy and clustering analysis, we discovered that in this process enzyme molecules form clusters with metal ions and organic ligands, contributing to both the nucleation and subsequent crystal growth. We proposed that the clusters played an important role in the retention of overall enzymatic activity by sacrificing protein molecules on the cluster surface. This work offers fresh perspectives on protein behaviors in the formation of P@MOFs, inspiring future endeavors in the design and development of artificial bionanocomposites with high biological activities.


Asunto(s)
Estructuras Metalorgánicas , Estructuras Metalorgánicas/química , Proteínas/química
5.
Small ; 20(2): e2305277, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37661569

RESUMEN

How to better understand the influence of electromagnetic parameters on the absorbing properties of electromagnetic wave absorbers (EMAs) is an essential prerequisite for further synthesis and development of high-performance EMAs. In this work, an improved wave cancellation theory is used as a guiding principle to prepare N-doped carbon-coated cobalt nanoparticles (Co@NC) using ZIF-8@ZIF-67 as the precursor, thus enabling controllable electromagnetic parameters by regulating the conduction loss and dipole polarization ability. The Co@NC generated by pyrolysis at 700 °C under H2 atmosphere presents an optimized absorption performance. Benefiting from developed wave cancellation theory, the thickness of the film can be accurately adjusted so that the difference between the amplitude of the reflected and transmitted electromagnetic waves is only 0.001 and the phase difference is 180.05°, thus achieving a minimum reflection loss (RLmin (dB)) of -64.0 dB. Meanwhile, a maximum effective absorption bandwidth of 5.4 GHz is achieved simultaneously attributing to its most suitable electromagnetic parameters. Accordingly, the current research based on wave cancellation theory significantly contributes to understand the relationships between electromagnetic parameters and wave absorption properties, therefore providing a theoretical insight into the further development of high-performance EMAs.

6.
Am Heart J ; 273: 90-101, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38575049

RESUMEN

BACKGROUND: Hypertension management in China is suboptimal with high prevalence and low control rate due to various barriers, including lack of self-management awareness of patients and inadequate capacity of physicians. Digital therapeutic interventions including mobile health and computational device algorithms such as clinical decision support systems (CDSS) are scalable with the potential to improve blood pressure (BP) management and strengthen the healthcare system in resource-constrained areas, yet their effectiveness remains to be tested. The aim of this report is to describe the protocol of the Comprehensive intelligent Hypertension managEment SyStem (CHESS) evaluation study assessing the effect of a multifaceted hypertension management system for supporting patients and physicians on BP lowering in primary care settings. MATERIALS AND METHODS: The CHESS evaluation study is a parallel-group, cluster-randomized controlled trial conducted in primary care settings in China. Forty-one primary care sites from 3 counties of China are randomly assigned to either the usual care or the intervention group with the implementation of the CHESS system, more than 1,600 patients aged 35 to 80 years with uncontrolled hypertension and access to a smartphone by themselves or relatives are recruited into the study and followed up for 12 months. In the intervention group, participants receive patient-tailored reminders and alerts via messages or intelligent voice calls triggered by uploaded home blood pressure monitoring data and participants' characteristics, while physicians receive guideline-based prescription instructions according to updated individual data from each visit, and administrators receive auto-renewed feedback of hypertension management performance from the data analysis platform. The multiple components of the CHESS system can work synergistically and have undergone rigorous development and pilot evaluation using a theory-informed approach. The primary outcome is the mean change in 24-hour ambulatory systolic BP from baseline to 12 months. DISCUSSION: The CHESS trial will provide evidence and novel insight into the effectiveness and feasibility of an implementation strategy using a comprehensive digital BP management system for reducing hypertension burden in primary care settings. TRIAL REGISTRATION: https://www. CLINICALTRIALS: gov, NCT05605418.


Asunto(s)
Hipertensión , Atención Primaria de Salud , Humanos , Hipertensión/terapia , Hipertensión/tratamiento farmacológico , Persona de Mediana Edad , Masculino , Femenino , China/epidemiología , Adulto , Anciano , Sistemas de Apoyo a Decisiones Clínicas , Telemedicina , Teléfono Inteligente , Anciano de 80 o más Años , Monitoreo Ambulatorio de la Presión Arterial/métodos , Sistemas Recordatorios
7.
Cardiovasc Diabetol ; 23(1): 190, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38824608

RESUMEN

BACKGROUND: Coronary three-vessel disease (CTVD) accounts for one-third of the overall incidence of coronary artery disease, with heightened mortality rates compared to single-vessel lesions, including common trunk lesions. Dysregulated glucose metabolism exacerbates atherosclerosis and increases cardiovascular risk. The stress hyperglycemia ratio (SHR) is proposed as an indicator of glucose metabolism status but its association with cardiovascular outcomes in CTVD patients undergoing percutaneous coronary intervention (PCI) remains unclear. METHODS: 10,532 CTVD patients undergoing PCI were consecutively enrolled. SHR was calculated using the formula: admission blood glucose (mmol/L)/[1.59×HbA1c (%)-2.59]. Patients were divided into two groups (SHR Low and SHR High) according to the optimal cutoff value of SHR. Multivariable Cox regression models were used to assess the relationship between SHR and long-term prognosis. The primary endpoint was cardiovascular (CV) events, composing of cardiac death and non-fatal myocardial infarction (MI). RESULTS: During the median follow-up time of 3 years, a total of 279 cases (2.6%) of CV events were recorded. Multivariable Cox analyses showed that high SHR was associated with a significantly higher risk of CV events [Hazard Ratio (HR) 1.99, 95% Confidence interval (CI) 1.58-2.52, P < 0.001). This association remained consistent in patients with (HR 1.50, 95% CI 1.08-2.10, P = 0.016) and without diabetes (HR 1.97, 95% CI 1.42-2.72, P < 0.001). Additionally, adding SHR to the base model of traditional risk factors led to a significant improvement in the C-index, net reclassification and integrated discrimination. CONCLUSIONS: SHR was a significant predictor for adverse CV outcomes in CTVD patients with or without diabetes, which suggested that it could aid in the risk stratification in this particular population regardless of glucose metabolism status.


Asunto(s)
Biomarcadores , Glucemia , Enfermedad de la Arteria Coronaria , Hiperglucemia , Intervención Coronaria Percutánea , Humanos , Masculino , Femenino , Persona de Mediana Edad , Anciano , Glucemia/metabolismo , Medición de Riesgo , Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Enfermedad de la Arteria Coronaria/sangre , Enfermedad de la Arteria Coronaria/mortalidad , Enfermedad de la Arteria Coronaria/terapia , Enfermedad de la Arteria Coronaria/epidemiología , Enfermedad de la Arteria Coronaria/diagnóstico , Biomarcadores/sangre , Factores de Riesgo , Intervención Coronaria Percutánea/efectos adversos , Intervención Coronaria Percutánea/mortalidad , Factores de Tiempo , Hiperglucemia/sangre , Hiperglucemia/diagnóstico , Hiperglucemia/epidemiología , Hiperglucemia/mortalidad , Resultado del Tratamiento , Hemoglobina Glucada/metabolismo , Valor Predictivo de las Pruebas , Estudios Retrospectivos , Infarto del Miocardio/sangre , Infarto del Miocardio/epidemiología , Infarto del Miocardio/diagnóstico , Infarto del Miocardio/mortalidad
8.
Clin Chem Lab Med ; 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38687473

RESUMEN

OBJECTIVES: Accurate measurements of renin and aldosterone levels play an important role in primary aldosteronism screening, which is of great importance in the management and categorization of hypertension. The objective of this study is to investigate the current status of plasma renin and aldosterone measurements in China, which is achieved by analyzing the results of 526 clinical laboratories nationwide for three pooled fresh plasma samples derived from more than 2,000 patients. METHODS: Renin and aldosterone in three pooled plasma samples were measured four times in 526 laboratories employing various measurement systems. The inter- and intra-laboratory %CV were calculated and compared. To determine the source of the substantial inter-laboratory %CV, laboratories were categorized according to the measurement systems they are using, and both the inter- and intra-measurement-system %CV were calculated and compared. RESULTS: Regarding renin, the majority of laboratories use four primary commercial immunoassays. However, for aldosterone, in addition to commercial immunoassays, laboratory-developed liquid chromatography-tandem mass spectrometry (LC-MS) methods are also used by laboratories. The median values of intra-laboratory %CVs, intra-measurement-system %CVs, inter-laboratory %CVs, and inter-measurement systems %CVs varied between 1.6 and 2.6 %, 4.6 and 14.9 %, 8.3 and 25.7 %, and 10.0 and 34.4 % for renin, respectively. For aldosterone, these values ranged from 1.4 to 2.2 %, 2.5-14.7 %, 9.9-31.0 %, and 10.0-35.5 %, respectively. CONCLUSIONS: The precision within laboratories and measurement systems for plasma renin and aldosterone measurements is satisfactory. However, the comparability between laboratories using different measurement systems remains lacking, indicating the long way to achieve standardization and harmonization for these two analytes.

9.
Inj Prev ; 2024 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-38443161

RESUMEN

BACKGROUND: Several previous studies have examined the association of ambient temperature with drowning. However, no study has investigated the effects of heat-humidity compound events on drowning mortality. METHODS: The drowning mortality data and meteorological data during the five hottest months (May to September) were collected from 46 cities in Southern China (2013-2018 in Guangdong, Hunan and Zhejiang provinces). Distributed lag non-linear model was first conducted to examine the association between heat-humidity compound events and drowning mortality at city level. Then, meta-analysis was employed to pool the city-specific exposure-response associations. Finally, we analysed the additive interaction of heat and humidity on drowning mortality. RESULTS: Compared with wet-non-hot days, dry-hot days had greater effects (excess rate (ER)=32.34%, 95% CI: 24.64 to 40.50) on drowning mortality than wet-hot days (ER=14.38%, 95%CI: 6.80 to 22.50). During dry-hot days, males (ER=42.40%, 95% CI: 31.92 to 53.72), adolescents aged 0-14 years (ER=45.00%, 95% CI: 21.98 to 72.35) and urban city (ER=36.91%, 95% CI: 23.87 to 51.32) showed higher drowning mortality risk than their counterparts. For wet-hot days, males, adolescents and urban city had higher ERs than their counterparts. Attributable fraction (AF) of drowning attributed to dry-hot days was 23.83% (95% CI: 21.67 to 26.99) which was significantly higher than that for wet-hot days (11.32%, 95% CI: 9.64 to 13.48%). We also observed that high temperature and low humidity had an additive interaction on drowning mortality. CONCLUSION: We found that dry-hot days had greater drowning mortality risk and burden than wet-hot days, and high temperature and low humidity might have synergy on drowning mortality.

10.
BMC Public Health ; 24(1): 350, 2024 02 02.
Artículo en Inglés | MEDLINE | ID: mdl-38308279

RESUMEN

BACKGROUND: The COVID-19 pandemic has resulted in significant excess mortality globally. However, the differences in excess mortality between the Omicron and non-Omicron waves, as well as the contribution of local epidemiological characteristics, population immunity, and social factors to excess mortality, remain poorly understood. This study aims to solve the above problems. METHODS: Weekly all-cause death data and covariates from 29 countries for the period 2015-2022 were collected and used. The Bayesian Structured Time Series Model predicted expected weekly deaths, stratified by gender and age groups for the period 2020-2022. The quantile-based g-computation approach accounted for the effects of factors on the excess all-cause mortality rate. Sensitivity analyses were conducted using alternative Omicron proportion thresholds. RESULTS: From the first week of 2021 to the 30th week of 2022, the estimated cumulative number of excess deaths due to COVID-19 globally was nearly 1.39 million. The estimated weekly excess all-cause mortality rate in the 29 countries was approximately 2.17 per 100,000 (95% CI: 1.47 to 2.86). Weekly all-cause excess mortality rates were significantly higher in both male and female groups and all age groups during the non-Omicron wave, except for those younger than 15 years (P < 0.001). Sensitivity analysis confirmed the stability of the results. Positive associations with all-cause excess mortality were found for the constituent ratio of non-Omicron in all variants, new cases per million, positive rate, cardiovascular death rate, people fully vaccinated per hundred, extreme poverty, hospital patients per million humans, people vaccinated per hundred, and stringency index. Conversely, other factors demonstrated negative associations with all-cause excess mortality from the first week of 2021 to the 30th week of 2022. CONCLUSION: Our findings indicate that the COVID-19 Omicron wave was associated with lower excess mortality compared to the non-Omicron wave. This study's analysis of the factors influencing excess deaths suggests that effective strategies to mitigate all-cause mortality include improving economic conditions, promoting widespread vaccination, and enhancing overall population health. Implementing these measures could significantly reduce the burden of COVID-19, facilitate coexistence with the virus, and potentially contribute to its elimination.


Asunto(s)
COVID-19 , Humanos , Femenino , Masculino , Adolescente , Teorema de Bayes , Pandemias , Factores de Tiempo , Proyectos de Investigación , Mortalidad
11.
Biomed Chromatogr ; 38(6): e5855, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38442715

RESUMEN

Metabolite profiling has the potential to comprehensively bridge phenotypes and complex heterogeneous physiological and pathological states. We performed a metabolomics study using parallel liquid chromatography-mass spectrometry (LC-MS) combined with multivariate data analysis to screen for biomarkers of primary aldosteronism (PA) from a cohort of 111 PA patients and 218 primary hypertension (PH) patients. Hydrophilic interaction chromatography and reversed-phase liquid chromatography separations were employed to obtain a global plasma metabolome of endogenous metabolites. The satisfactory classification between PA and PH patients was obtained using the MVDA model. A total of 35 differential metabolites were screened out and identified. A diagnostic biomarker panel was established using the least absolute shrinkage and selection operator (LASSO) binary logistic regression model and receiver operating characteristic analysis. Joint analysis with clinical indicators, including plasma supine aldosterone level, plasma orthostatic aldosterone level, body mass index, and blood potassium, revealed that the combination of metabolite biomarker panel and plasma supine aldosterone has the best clinical diagnostic efficacy.


Asunto(s)
Biomarcadores , Hiperaldosteronismo , Espectrometría de Masas , Metabolómica , Humanos , Hiperaldosteronismo/sangre , Hiperaldosteronismo/diagnóstico , Metabolómica/métodos , Biomarcadores/sangre , Femenino , Persona de Mediana Edad , Masculino , Espectrometría de Masas/métodos , Cromatografía Liquida/métodos , Metaboloma/fisiología , Adulto , Aldosterona/sangre , Cromatografía Líquida con Espectrometría de Masas
12.
Ecotoxicol Environ Saf ; 280: 116525, 2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-38852468

RESUMEN

Air pollution is widely acknowledged as a significant risk factor for human health, especially reproductive health. Nevertheless, many studies have disregarded the potentially mixed effects of air pollutants on reproductive outcomes. We performed a retrospective cohort study involving 8048 women with 9445 cycles undergoing In Vitro Fertilization (IVF) and Intracytoplasmic Sperm Injection (ICSI) in China, from 2017 to 2021. A land-use random forest model was applied to estimate daily residential exposure to air pollutants, including sulfur dioxide (SO2), nitrogen dioxide (NO2), carbon monoxide (CO), ozone (O3), and fine particulate matter (PM2.5). Individual and joint associations between air pollutants and oocyte-related outcomes of ART were evaluated. In 90 days prior to oocyte pick-up to oocyte pick-up (period A), NO2, O3 and CO was negatively associated with total oocyte yield. In the 90 days prior to oocyte pick-up to start of gonadotropin medication (Gn start, period B), there was a negative dose-dependent association of exposure to five air pollutants with total oocyte yield and mature oocyte yield. In Qgcomp analysis, increasing the multiple air pollutants mixtures by one quartile was related to reducing the number of oocyte pick-ups by -2.00 % (95 %CI: -2.78 %, -1.22 %) in period A, -2.62 % (95 %CI: -3.40 %, -1.84 %) in period B, and -0.98 % (95 %CI: -1.75 %, -0.21 %) in period C. During period B, a 1-unit increase in the WQS index of multiple air pollutants exposure was associated with fewer number of total oocyte (-1.27 %, 95 %CI: -2.16 %, -0.36 %) and mature oocyte (-1.42 %, 95 %CI: -2.41 %, -0.43 %). O3 and NO2 were major contributors with adverse effects on the mixed associations. Additionally, period B appears to be the susceptible window. Our study implies that exposure to air pollution adversely affects oocyte-related outcomes, which raises concerns about the potential adverse impact of air pollution on women's reproductive health.


Asunto(s)
Contaminantes Atmosféricos , Oocitos , Femenino , Humanos , Contaminantes Atmosféricos/toxicidad , Contaminantes Atmosféricos/análisis , Estudios Retrospectivos , Oocitos/efectos de los fármacos , Adulto , China , Técnicas Reproductivas Asistidas , Contaminación del Aire/efectos adversos , Ozono , Material Particulado/toxicidad , Material Particulado/análisis , Exposición a Riesgos Ambientales/efectos adversos , Fertilización In Vitro , Estudios de Cohortes , Dióxido de Nitrógeno/análisis
13.
BMC Med ; 21(1): 192, 2023 05 24.
Artículo en Inglés | MEDLINE | ID: mdl-37226271

RESUMEN

BACKGROUND: Both low-carbohydrate (LC) and calorie-restricted (CR) diets have been shown to have metabolic benefits. However, the two regimens have yet to be thoroughly compared. We conducted a 12-week randomized trial to compare the effects of these diets separately and in combination on both weight loss and metabolic risk factors in overweight/obese individuals. METHODS: A total of 302 participants were randomized to LC diet (n = 76), CR diet (n = 75), LC + CR diet (n = 76), or normal control (NC) diet (n = 75) using a computer-based random number generator. The primary outcome was the change in body mass index (BMI). The secondary outcomes included body weight, waist circumference, waist-to-hip ratio, body fat, and metabolic risk factors. All participants attended health education sessions during the trial. RESULTS: A total of 298 participants were analyzed. BMI change over 12 weeks was - 0.6 (95% CI, - 0.8 to - 0.3) kg/m2 in NC, - 1.3 (95% CI, - 1.5 to - 1.1) kg/m2 in CR, - 2.3 (95% CI, - 2.6 to - 2.1) kg/m2 in LC, and - 2.9 (95% CI, - 3.2 to - 2.6) kg/m2 in LC + CR. LC + CR diet was more effective than LC or CR diet alone at reducing BMI (P = 0.001 and P < 0.001, respectively). Furthermore, compared with the CR diet, the LC + CR diet and LC diet further reduced body weight, waist circumference, and body fat. Serum triglycerides were significantly reduced in the LC + CR diet group compared with the LC or CR diet alone. Plasma glucose, homeostasis model assessment of insulin resistance, and cholesterol concentrations (total, LDL, and HDL) did not change significantly between the groups during the 12-week intervention. CONCLUSIONS: The reduction of carbohydrate intake without restricting caloric intake is more potent to achieve weight loss over 12 weeks when compared to a calorie-restricted diet in overweight/obese adults. The combination of restricting carbohydrate and total calorie intake may augment the beneficial effects of reducing BMI, body weight, and metabolic risk factors among overweight/obese individuals. TRIAL REGISTRATION: The study was approved by the institutional review board of Zhujiang Hospital of Southern Medical University and registered at the China Clinical Trial Registration Center (registration number: ChiCTR1800015156).


Asunto(s)
Carbohidratos de la Dieta , Sobrepeso , Adulto , Humanos , Restricción Calórica , Obesidad , Dieta Baja en Carbohidratos
14.
Small ; 19(49): e2305353, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37606896

RESUMEN

The combination of 2D magnetic nanosheets and mesoporous carbon with unique interfaces shows considerable prospects for microwave absorption (MA). However, traditional assembly procedures make it impossible to accurately manage the assembly of magnetic nanosheets in carbon matrices. Herein, a reverse strategy for preparing complex magnetic nanosheet cores inside carbon-based yolk-shell structures is developed. This innovative approach focuses on controlling the initial crystallite formation sites in a hydrothermal reaction as well as the inflow and in situ growth behavior of 2D NiCo-layered double hydroxide precursors based on the capillary force induced by hollow mesoporous carbon nanospheres. Accordingly, the as-prepared YS-CNC-2 absorber exhibits remarkable MA performances, with an optimal reflection loss as low as -60.30 dB at 2.5 mm and an effective absorption bandwidth of 5.20 GHz at 2.0 mm. The loss of electromagnetic waves (EMW) depends on natural resonance loss, dipole polarization relaxation, and multiple scattering behavior. On top of that, the functionalized super-hydrophobic MA coating is produced in spraying and curing processes utilizing YS-CNC-2 nanoparticles and fumed silica additives in the polydimethylsiloxane matrix. The excellent thermal insulation, self-cleaning capability, and durability in diverse solutions of the coating promise potential applications for military equipment in moist situations.

15.
Small ; 19(1): e2204649, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36354192

RESUMEN

The construction of ordered hierarchical porous structures in metal-organic frameworks (MOFs) and their derivatives is highly promising to meet the low-density and high-performance demands of microwave absorption materials. However, traditional methods based on sacrificial templates or corrosive agents inevitably suffer from the collapse of the microporous framework and the accumulation of nanoparticles during the carbonization transformation, resulting in the deteriorating impedance match, which greatly limits the incident and attenuation of microwaves. Herein, an induced crystallization and controllable nanoarchitectonics strategy is employed to replace traditional growing-etching methods and successfully synthesize carbonized 3D-ordered macroporous Co@N-doped carbon (3DOM Co@NDC) based on the 3D-ordered template. The obtained 3D-ordered macroporous structure ensures the stable growth of hybrid carbon frameworks and CoC nanoparticles without collapse, preserves abundant interfaces for both the incident and attenuation performance, so as to significantly improve the impedance matching and absorption properties compared to conventional MOFs derivatives. The minimum reflection loss of 3DOM Co@NDC is -57.36 dB at the thickness of 1.9 mm, and the effective bandwidth is 7.36 GHz at 1.6 mm. Moreover, the innovative strategy to prepare 3D-ordered hierarchical macroporous structures opens up a new avenue for advanced MOFs-derived absorbers with excellent performance.

16.
Small ; 19(40): e2302961, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37264718

RESUMEN

Constructing the adjustable surface conductive networks is an innovation that can achieve a balance between enhanced attenuation and impedance mismatch according to the microwave absorption mechanism. However, the traditional design strategies remain significant challenges in terms of rational selection and controlled growth of conductive components. Herein, a hierarchical construction strategy and quantitative construction technique are employed to introduce conductive metal-organic frameworks (MOFs) derivatives in the classic yolk-shell structure composed of electromagnetic components and the cavity for remarkable optimized performance. Specifically, the surface conductive networks obtained by carbonized ZIF-67 quantitative construction, together with the Fe3 O4 magnetic core and dielectric carbon layer linked by the cavity, achieve the cooperative enhancement of impedance matching optimization and synergistic attenuation in the Fe3 O4 @C@Co/N-Doped C (FCCNC) absorber. This interesting design is further verified by experimental results and simulation calculations. The products FCCNC-2 yield a distinguished minimum reflection loss of -66.39 dB and an exceptional effective absorption bandwidth of 6.49 GHz, indicating that moderate conduction excited via hierarchical and quantitative design can maximize the absorption capability. Furthermore, the proposed versatile methodology of surface assembly paves a new avenue to maximize beneficial conduction effect and manipulate microwave attenuation in MOFs derivatives.

17.
J Med Virol ; 95(2): e28492, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36633204

RESUMEN

Mammalian orthoreovirus (MRV) infects many mammalian species including humans, bats, and domestic animals. To determine the prevalence of MRV in bats in the United States, we screened more than 900 bats of different species collected during 2015-2019 by a real-time reverse-transcription polymerase chain reaction assay; 4.4% bats tested MRV-positive and 13 MRVs were isolated. Sequence and phylogenetic analysis revealed that these isolates belonged to four different strains/genotypes of viruses in Serotypes 1 or 2, which contain genes similar to those of MRVs detected in humans, bats, bovine, and deer. Further characterization showed that these four MRV strains replicated efficiently on human, canine, monkey, ferret, and swine cell lines. The 40/Bat/USA/2018 strain belonging to the Serotype 1 demonstrated the ability to infect and transmit in pigs without prior adaptation. Taken together, this is evidence for different genotypes and serotypes of MRVs circulating in US bats, which can be a mixing vessel of MRVs that may spread to other species, including humans, resulting in cross-species infections.


Asunto(s)
Quirópteros , Ciervos , Orthoreovirus de los Mamíferos , Orthoreovirus , Animales , Perros , Humanos , Bovinos , Estados Unidos , Porcinos , Orthoreovirus de los Mamíferos/genética , Filogenia , Hurones
18.
Epidemiology ; 34(2): 282-292, 2023 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-36722811

RESUMEN

BACKGROUND: Studies have estimated the associations of short-term exposure to ambient air pollution with ischemic stroke. However, the joint associations of ischemic stroke with air pollution as a mixture remain unknown. METHODS: We employed a time-stratified case-crossover study to investigate 824,808 ischemic stroke patients across China. We calculated daily mean concentrations of particulate matter with an aerodynamic diameter ≤2.5 µm (PM2.5), maximum 8-h average for O3 (MDA8 O3), nitrogen dioxide (NO2), sulfur dioxide (SO2), and carbon monoxide (CO) across all monitoring stations in the city where the IS patients resided. We conducted conditional logistic regression models to estimate the exposure-response associations. RESULTS: Results from single-pollutant models showed positive associations of hospital admission for ischemic stroke with PM2.5 (excess risk [ER] = 0.38%, 95% confidence interval [CI]: 0.29% to 0.47%, for 10 µg/m3), MDA8 O3 (ER = 0.29%, 95% CI: 0.18% to 0.40%, for 10 µg/m3), NO2 (ER = 1.15%, 95% CI: 0.92% to 1.39%, for 10 µg/m3), SO2 (ER = 0.82%, 95% CI: 0.53% to 1.11%, for 10 µg/m3) and CO (ER = 3.47%, 95% CI: 2.70% to 4.26%, for 1 mg/m3). The joint associations (ER) with all air pollutants (for interquartile range width increases in each pollutant) estimated by the single-pollutant model was 8.73% and was 4.27% by the multipollutant model. The joint attributable fraction of ischemic stroke attributable to air pollutants based on the multipollutant model was 7%. CONCLUSIONS: Short-term exposures to PM2.5, MDA8 O3, NO2, SO2, and CO were positively associated with increased risks of hospital admission for ischemic stroke. The joint associations of air pollutants with ischemic stroke might be overestimated using single-pollutant models. See video abstract at, http://links.lww.com/EDE/C8.


Asunto(s)
Contaminantes Atmosféricos , Accidente Cerebrovascular Isquémico , Humanos , Contaminantes Atmosféricos/efectos adversos , Estudios Cruzados , Accidente Cerebrovascular Isquémico/inducido químicamente , Accidente Cerebrovascular Isquémico/terapia , Dióxido de Nitrógeno/efectos adversos , Material Particulado/efectos adversos , Dióxido de Azufre/efectos adversos , Admisión del Paciente
19.
PLoS Comput Biol ; 18(6): e1010218, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35759513

RESUMEN

As a common vector-borne disease, dengue fever remains challenging to predict due to large variations in epidemic size across seasons driven by a number of factors including population susceptibility, mosquito density, meteorological conditions, geographical factors, and human mobility. An ensemble forecast system for dengue fever is first proposed that addresses the difficulty of predicting outbreaks with drastically different scales. The ensemble forecast system based on a susceptible-infected-recovered (SIR) type of compartmental model coupled with a data assimilation method called the ensemble adjusted Kalman filter (EAKF) is constructed to generate real-time forecasts of dengue fever spread dynamics. The model was informed by meteorological and mosquito density information to depict the transmission of dengue virus among human and mosquito populations, and generate predictions. To account for the dramatic variations of outbreak size in different seasons, the effective population size parameter that is sequentially updated to adjust the predicted outbreak scale is introduced into the model. Before optimizing the transmission model, we update the effective population size using the most recent observations and historical records so that the predicted outbreak size is dynamically adjusted. In the retrospective forecast of dengue outbreaks in Guangzhou, China during the 2011-2017 seasons, the proposed forecast model generates accurate projections of peak timing, peak intensity, and total incidence, outperforming a generalized additive model approach. The ensemble forecast system can be operated in real-time and inform control planning to reduce the burden of dengue fever.


Asunto(s)
Culicidae , Dengue , Animales , China/epidemiología , Brotes de Enfermedades , Humanos , Mosquitos Vectores , Estudios Retrospectivos
20.
Epidemiol Infect ; 151: e39, 2023 02 20.
Artículo en Inglés | MEDLINE | ID: mdl-36803678

RESUMEN

We developed a mechanism model which allows for simulating the novel coronavirus (COVID-19) transmission dynamics with the combined effects of human adaptive behaviours and vaccination, aiming at predicting the end time of COVID-19 infection in global scale. Based on the surveillance information (reported cases and vaccination data) between 22 January 2020 and 18 July 2022, we validated the model by Markov Chain Monte Carlo (MCMC) fitting method. We found that (1) if without adaptive behaviours, the epidemic could sweep the world in 2022 and 2023, causing 3.098 billion of human infections, which is 5.39 times of current number; (2) 645 million people could be avoided from infection due to vaccination; and (3) in current scenarios of protective behaviours and vaccination, infection cases would increase slowly, levelling off around 2023, and it would end completely in June 2025, causing 1.024 billion infections, with 12.5 million death. Our findings suggest that vaccination and the collective protection behaviour remain the key determinants against the global process of COVID-19 transmission.


Asunto(s)
COVID-19 , Humanos , COVID-19/epidemiología , COVID-19/prevención & control , Pandemias/prevención & control , Adaptación Psicológica , SARS-CoV-2 , Vacunación
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