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The introduction of lanthanide ions (Ln3+) into all-inorganic lead-free halide perovskites has captured significant attention in optoelectronic applications. However, doping Ln3+ ions into heterometallic halide layered double perovskite (LDP) nanocrystals (NCs) and their associated doping mechanisms remain unexplored. Herein, we report the first colloidal synthesis of Ln3+ (Yb3+, Er3+)-doped LDP NCs utilizing a modified hot-injection method. The resulting NCs exhibit efficient near-infrared (NIR) photoluminescence in both NIR-I and NIR-II regions, achieved through energy transfer down-conversion mechanisms. Density functional theory calculations reveal that Ln3+ dopants preferentially occupy the Sb3+ cation positions, resulting in a disruption of local site symmetry of the LDP lattices. By leveraging sensitizations of intermediate energy levels, we delved into a series of Ln3+-doped Cs4M(II)Sb2Cl12 (M(II): Cd2+ or Mn2+) LDP NCs via co-doping strategies. Remarkably, we observe a brightening effect of the predark states of Er3+ dopant in the Er3+-doped Cs4M(II)Sb2Cl12 LDP NCs owing to the Mn component acting as an intermediate energy bridge. This study not only advances our understanding of energy transfer mechanisms in doped NCs but also propels all-inorganic LDP NCs for a wider range of optoelectronic applications.
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The cluster-based body-centered-cubic superlattice (cBCC SL) represents one of the most complicated structures among reported nanocrystal assemblies, comprised of 72 truncated tetrahedral quantum dots per unit cell. Our previous report revealed that truncated tetrahedral quantum dots within cBCC SLs possessed highly controlled translational and orientational order owing to an unusual energetic landscape based on the balancing of entropic and enthalpic contributions during the assembly process. However, the cBCC SL's structural transformability and mechanical properties, uniquely originating from such complicated nanostructures, have yet to be investigated. Herein, we report that cBCC SLs can undergo dynamic transformation to face-centered-cubic SLs in response to post-assembly molecular exposure. We monitored the dynamic transformation process using in situ synchrotron-based small-angle X-ray scattering, revealing a dynamic transformation involving multiple steps underpinned by interactions between incoming molecules and TTQDs' surface ligands. Furthermore, our mechanistic study demonstrated that the precise configuration of TTQDs' ligand molecules in cBCC SLs was key to their high structural transformability and unique jelly-like soft mechanical properties. While ligand molecular configurations in nanocrystal SLs are often considered minor features, our findings emphasize their significance in controlling weak van der Waals interactions between nanocrystals within assembled SLs, leading to previously unremarked superstructural transformability and unique mechanical properties. Our findings promote a facile route toward further creation of soft materials, nanorobotics, and out-of-equilibrium assemblies based on nanocrystal building blocks.
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Finding personalized biomarkers for disease prediction of patients with cancer remains a massive challenge in precision medicine. Most methods focus on one subnetwork or module as a network biomarker; however, this ignores the early warning capabilities of other modules with different configurations of biomarkers (i.e. multi-modal personalized biomarkers). Identifying such modules would not only predict disease but also provide effective therapeutic drug target information for individual patients. To solve this problem, we developed a novel model (denoted multi-modal personalized dynamic network biomarkers (MMPDNB)) based on a multi-modal optimization mechanism and personalized dynamic network biomarker (PDNB) theory, which can provide multiple modules of personalized biomarkers and unveil their multi-modal properties. Using the genomics data of patients with breast or lung cancer from The Cancer Genome Atlas database, we validated the effectiveness of the MMPDNB model. The experimental results showed that compared with other advanced methods, MMPDNB can more effectively predict the critical state with the highest early warning signal score during cancer development. Furthermore, MMPDNB more significantly identified PDNBs containing driver and biomarker genes specific to cancer tissues. More importantly, we validated the biological significance of multi-modal PDNBs, which could provide effective drug targets of individual patients as well as markers for predicting early warning signals of the critical disease state. In conclusion, multi-modal optimization is an effective method to identify PDNBs and offers a new perspective for understanding tumor heterogeneity in cancer precision medicine.
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Genômica , Neoplasias Pulmonares , Biomarcadores , Genômica/métodos , Humanos , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/genética , Medicina de Precisão/métodosRESUMO
Polarization control with nanostructures having a tunable design and allowing inexpensive large-scale fabrication is important for many nanophotonic applications. For this purpose, we developed and experimentally demonstrated nanostructured plasmonic surfaces based on hexagonal arrays of anisotropic coaxial nanocavities, which can be fabricated by a low-cost self-assembled nanosphere lithography method. Their high polarization sensitivity is achieved by engineering anisotropy of the coaxial nanocavities, while the optical response is enhanced by the excitation of surface plasmon resonances. Particularly, varying the geometrical parameters of the coaxial nanocavities, namely the height and tilt angle of their central core nanoellipsoids, the plasmonic resonance wavelengths as well as the polarization-selective behavior can be individually tuned in the entire visible and near-infrared spectral regions, which makes such nanostructures good candidates for the implementation of polarization-controlled optical switches and polarization-tunable filters. Moreover, the developed nanostructures demonstrate sensitivity up to 1335 nm/RIU in refractive index sensing.
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Space-based solar power harvesting systems with high levels of specific power (the power produced per mass of the mounted photovoltaic cell) are highly desired. In this study, we synthesized high quality lead-free Cs3Cu2Cl5 perovskite nanodisks with efficient ultraviolet (UV) photon absorption, high photoluminescence quantum yields, and a large Stokes shift, which are suitable to serve as photon energy downshifting emitters in the applications of photon-managing devices especially for space solar power harvesting. To demonstrate this possibility, we have fabricated two types of photon-managing devices, i.e., luminescent solar concentrators (LSCs) and luminescent downshifting (LDS) layers. Both experimental results and simulation analyses show that the fabricated LSC and LDS devices exhibit high visible light transmission, low photon scattering and reabsorption energy loss, high UV photon harvesting, and energy conversion after integrating with silicon-based photovoltaic cells. Our research presents a new avenue for utilizing lead-free perovskite nanomaterials in space applications.
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Developing Type-I core/shell quantum dots is of great importance toward fabricating stable and sustainable photocatalysts. However, the application of Type-I systems has been limited due to the strongly confined photogenerated charges by the energy barrier originating from the wide-bandgap shell material. In this project, we found that through the decoration of Au satellite-type domains on the surface of Type-I CdS/ZnS core/shell quantum dots, such an energy barrier can be effectively overcome and an over 400-fold enhancement of photocatalytic H2 evolution rate was achieved compared to bare CdS/ZnS quantum dots. Transient absorption spectroscopic studies indicated that the charges can be effectively extracted and subsequently transferred to surrounding molecular substrates in a subpicosecond time scale in such hybrid nanocrystals. Based on density functional theory calculations, the ultrafast charge separation rates were ascribed to the formation of intermediate Au2S layer at the semiconductor-metal interface, which can successfully offset the energy confinement introduced by the ZnS shell. Our findings not only provide insightful understandings on charge carrier dynamics in semiconductor-metal heterostructural materials but also pave the way for the future design of quantum dot-based hybrid photocatalytic systems.
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Dissolved organic matter (DOM) widely exists in aquatic environment and plays a critical role in environmental photochemical reaction. The photochemical behaviors of DOM in sunlit surface waters have received widely attention because its photochemical effects for some coexisted substances in aquatic environment, especially for organic micropollutants degradation. Therefore, to gain a comprehensive understanding of the photochemical properties and environmental effects of DOM, we reviewed the influence of sources on the structure and composition of DOM with relevant identified techniques to analysis functional groups. Additionally, identification and quantification for reactive intermediates are discussed with a focus on influencing factors to produce reactive intermediates by DOM under solar irradiation. These reactive intermediates can promote the photodegradation of organic micropollutants in the environmental system. In future, attention should be paid to the photochemical properties of DOM and environmental effects in real environmental system and development of advanced techniques to study DOM.
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Matéria Orgânica Dissolvida , Energia Solar , FotóliseRESUMO
Previous researches have reported the association between air pollution and various diseases. However, few researches have investigated whether air pollutants are associated with the economic loss resulting from patients' hospitalization, especially the economic loss of hospitalization due to acute cardiovascular events. The purpose of our research was to explore the association between the levels of carbon monoxide (CO), taken as an index of pollution, and the hospitalization costs of myocardial infarction (MI), and the potential effect modification by the ABO blood group. A total of 3237 MI inpatients were included in this study. A multiple linear regression model was used to evaluate the association between ambient CO levels and hospitalization costs of MI patients. Moreover, we performed stratified analyses by age, gender, body mass index (BMI), season, hypertension, and ABO blood types. There was a positive association between the levels of CO in the air and the costs of hospitalization caused by MI. Furthermore, such association was stronger in males, BMI ≥25, <65 years, with hypertension, and non-O blood group. Interestingly, we found the association was particularly significant in patients with blood group B. Overall, our study first found that ambient CO levels could have an impact on the hospitalization costs for MI patients, and those with blood group B can be more sensitive.
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Poluentes Atmosféricos , Poluição do Ar , Hipertensão , Infarto do Miocárdio , Masculino , Humanos , Monóxido de Carbono/análise , Sistema ABO de Grupos Sanguíneos/análise , Poluição do Ar/análise , Poluentes Atmosféricos/toxicidade , Poluentes Atmosféricos/análise , Hospitalização , Infarto do Miocárdio/epidemiologia , Infarto do Miocárdio/induzido quimicamente , Hipertensão/induzido quimicamenteRESUMO
CO2 laser has been proposed as a treatment strategy for genitourinary syndrome of menopause (GSM). In order to assess its efficacy for treating GSM, we conducted a systematic review and meta-analysis. To identify the current state of randomized controlled trials on CO2 laser therapy for GSM, a literature review was conducted. We systematically searched the following databases: PUBMED, EMBASE and the Cochrane Controlled Trials Register. In addition, a review of the references in the retrieved studies was carried out. Of 562 identified studies, 9 were eligible and were included in our analysis, involving 523 patients in total. Based on our analysis, CO2 laser has no statistical difference compared with estrogen in VHI (p = 0.87), FSFI total score (p = 0.19), FSFI-Arousal (p = 0.11), FSFI-Desire (p = 0.72), FSFI-Orgasm (p = 0.45) and FSFI-Satisfaction (p = 0.08). The meta-analysis also showed that CO2 laser significantly improved FSFI-Lubrication scores compared with estrogen therapy (p = 0.0004). Furthermore, compared with the sham group, CO2 laser group had statistically improved VHI scores (p = 0.003) and FSFI scores (p < 0.00001). CO2 laser therapy may be an effective alternative to estrogen therapy for GSM both in cases where estrogen is not applicable because of comorbidities and in cases in which women do not desire to take estrogen.
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Dióxido de Carbono , Estrogênios , Humanos , Feminino , Ensaios Clínicos Controlados Aleatórios como Assunto , Menopausa , LasersRESUMO
Optical regulation strategy with the aid of hybrid materials can significantly optimize the performance of terahertz devices. Gold nanobipyramids (AuNBPs) with synthetical tunability to the near-infrared band show strong local field enhancement, which improves optical coupling at the interface and benefits the modulation performance. We design AuNBPs-integrated terahertz modulators with multiple structured surfaces and demonstrate that introducing AuNBPs can effectively enhance their modulation depths. In particular, an ultrahigh modulation enhancement of 1 order of magnitude can be achieved in the AuNBPs hybrid metamaterials accompanied by the multifunctional modulation characteristics. By application of the coupled Lorentz oscillator model, the theoretical calculation suggests that the optical regulation with AuNBPs originates from increased damping rate and higher coupling coefficient under pump excitation. Additionally, a terahertz spatial light modulator is constructed to demonstrate multiple imaging display and consume extremely low power, which is promising for the potential application in spatial and frequency selective imaging.
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Zika virus (ZIKV), which is mainly transmitted by Aedes albopictus in temperate zones, can causes serious neurological disorders. However, the molecular mechanisms that influence the vector competence of Ae. albopictus for ZIKV are poorly understood. In this study, the vector competence of Ae. albopictus mosquitoes from Jinghong (JH) and Guangzhou (GZ) Cities of China were evaluated, and transcripts in the midgut and salivary gland tissues were sequenced on 10 days post-infection. The results showed that both Ae. albopictus JH and GZ strains were susceptible to ZIKV, but the GZ strain was more competent. The categories and functions of differentially expressed genes (DEGs) in response to ZIKV infection were quite different between tissues and strains. Through a bioinformatics analysis, a total of 59 DEGs that may affect vector competence were screened-among which, cytochrome P450 304a1 (CYP304a1) was the only gene significantly downregulated in both tissues of two strains. However, CYP304a1 did not influence ZIKV infection and replication in Ae. albopictus under the conditions set in this study. Our results demonstrated that the different vector competence of Ae. albopictus for ZIKV may be determined by the transcripts in the midgut and salivary gland, which will contribute to understanding ZIKV-mosquito interactions and develop arbovirus disease prevention strategies.
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Aedes , Infecção por Zika virus , Zika virus , Animais , Zika virus/fisiologia , Mosquitos Vetores , Perfilação da Expressão GênicaRESUMO
BACKGROUND: Exercise boosts the health of some brain parts, such as the hippocampus and hypothalamus. Several studies show that long-term exercise improves spatial learning and memory, enhances hypothalamic leptin sensitivity, and regulates energy balance. However, the effect of exercise on the hippocampus and hypothalamus is not fully understood. The study aimed to find epigenetic modifications or changes in gene expression of the hippocampus and hypothalamus due to exercise. METHODS: Male C57BL/6 mice were randomly divided into sedentary and exercise groups. All mice in the exercise group were subjected to treadmill exercise 5 days per week for 1 h each day. After the 12-week exercise intervention, the hippocampus and hypothalamus tissue were used for RNA-sequencing or molecular biology experiments. RESULTS: In both groups, numerous differentially expressed genes of the hippocampus (up-regulated: 53, down-regulated: 49) and hypothalamus (up-regulated: 24, down-regulated: 40) were observed. In the exercise group, increased level of N6-methyladenosine (m6A) was observed in the hippocampus and hypothalamus (p < 0.05). Furthermore, the fat mass and obesity-associated gene (FTO) of the hippocampus and hypothalamus were down-regulated in the exercise group (p < 0.001). In addition, the Fto co-expression genes of the mouse brain were studied and analyzed using database to determine the potential roles of exercise-downregulated FTO in the brain. CONCLUSION: The findings demonstrate that long-term exercise might elevates the levels of m6A-tagged transcripts in the hippocampus and hypothalamus via down-regulation of FTO. Hence, exercise might be an effective intervention for epigenetic modification.
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Leptina , Animais , Epigênese Genética , Hipocampo/metabolismo , Hipotálamo/metabolismo , Leptina/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , RNA/metabolismoRESUMO
Traditional absorbers are mostly limited by their large size and high profile, which renders them unfavorable for practical devices. To solve this problem, we design and test an ultra-thin metamaterial absorber (UTMA). The top layer of the metamaterial absorber is designed as a patterned combination of split ring and metal strips, so that its resonant frequency point is in the target low frequency. Meanwhile, ohmic loss is enhanced by loading lumped resistance in the gap of the meta-surface to improve the absorb efficiency (> 90%) and to expand the working bandwidth (1.24-3.14â GHz). Moreover, the total thickness of the absorber is 9â mm (0.037λwith respect to the lowest operating frequency). The working mechanism of UTMA is analyzed based on the equivalent media theory, surface current and electric field energy distribution. The experimental results are in good agreement with the simulation, which verifies the feasibility of the design. In this work, the metamaterial absorber is designed to meet the target requirements from three performance indexes: low frequency, ultra-thin, and wideband, leading to the prospect of broad applications in the military and civil fields.
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In this paper, a novel broadband circularly polarized transmitarray antenna (CPTA) enabled by axial-ratio-improved receiver-transmitter metasurface loaded with parasitic patches is proposed. Split-ring-shaped parasitic patch is utilized to generate an additional resonant mode and significantly broaden the 3-dB axial ratio (AR) bandwidth of proposed receiver/transmitter patches from 6.64% to 15.61%. By cascading the receiver and transmitter with the same polarization and then rotating the cell, Pancharatnam-Berry phase can be exploited for providing a 2π phase shift. As verification, a CPTA prototype integrated with a self-made circularly polarized patch antenna is designed, fabricated, and measured. Experimental results show that the proposed CPTA obtains a 3-dB AR bandwidth of 27.1% from 12.1 to 15.9 GHz and an impedance bandwidth of 20.6% from 12.5 to 15.2 GHz. Additionally, it has a flat gain with a 3-dB gain bandwidth of 18.8% from 12.5 to 15.1 GHz, and a maximum gain of 25.6 dBi at 13.1 GHz is achieved. With the advantages of simple design, wide AR bandwidth, and flat gain performance, the proposed CPTA presents great potential applications in wireless systems.
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Stealth radome (SR), especially with an ultra-broad and nearly transparent window between two absorption bands, plays a crucial role in stealth techniques, antenna radomes, and so on. However, current devices have the defects of narrow transmission bands, high insertion loss, and wide transition bands between the transmission and absorption bands, which are unfavorable for the stealth of broadband radar and communication systems. In this paper, a novel SR with an ultra-broad and high-efficiency inter-absorption band transparent window is proposed by combining broadband resonance lumped circuits with a multi-layer cascaded frequency-selective surface (FSS). The equivalent circuit model (ECM) and transmission line method (TLM) are provided and analyzed as a guideline for the SR design. The SR consists of a resistive lossy layer loaded with wide passband lumped circuits and two stacked lossless FSS layers to collectively achieve the high selectivity and ultra-broad transmission band. Simulated results indicate that the proposed SR exhibits an ultra-broad passband from 8.2 to 11.2â GHz (31%) with transmission amplitude more than 0.85 and two 90% absorption bands over 6.8-7.8â GHz and 12-13â GHz, and the transition bands at both sides are only 0.4â GHz and 0.8â GHz, respectively. Our findings can stimulate the promising applications of SR in broadband stealth devices with integrated ultra-broad communication capability or in other electromagnetic (EM) compatibility facilities.
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Surface plasmon polaritons (SPPs) and their counterparts at low frequency (i.e., spoof SPPs) have been attracting a lot of attention recently due to their potential application for routing information with high speeds and bandwidth. To further develop integrated plasmonics, a high-efficiency surface plasmon coupler is required for full elimination of the intrinsic scattering and reflection when exciting the highly confined plasmonic modes, but a solution to this challenge has remained elusive so far. To take on this challenge, here we propose a feasible spoof SPP coupler based on a transparent Huygens' metasurface, which is able to realize more than 90% efficiency in near- and far-field experiments. To be specific, electrical and magnetic resonators are designed separately on both sides of the metasurface to satisfy the impedance-matching condition everywhere, leading to full conversion of plane wave propagation into surface wave propagation. Moreover, a well-optimized plasmonic metal which is able to support an eigen SPP is designed. This proposed high-efficiency spoof SPP coupler based on a Huygens' metasurface may pave the way for the development of high-performance plasmonic devices.
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Ambient carbon monoxide (CO) is associated with bronchitis morbidity, but there is no evidence concerning its correlation with hospitalization costs for bronchitis patients. This study aimed to investigate the relationship between short-term ambient CO exposure and hospitalization costs for bronchitis patients in Chongqing, China. Baseline data for 3162 hospitalized bronchitis patients from November 2013 to December 2019 were collected. Multiple linear regression analysis was used to determine the association, delayed and cumulative, between short-term CO exposure and hospitalization costs. Additionally, subgroup analyses were performed by gender, age, season, and comorbidity. Positive association between CO and hospitalization costs for bronchitis patients was observed. The strongest association was observed at lag 015 days, with per 1 mg/m3 increase of CO concentrations corresponded to 5834.40 Chinese Yuan (CNY) (95% CI: 2318.71, 9350.08; P < 0.001) (845.97 US dollars) increment in hospitalization costs. Stratified analysis results showed that the association was more obvious among those males, elderly, with comorbidities, and in warm seasons. More importantly, there was strongest correlation between CO and bronchitis patients with coronary heart disease. In summary, short-term exposure to ambient CO, even lower than Chinese and WHO standards, can be associated with increased hospitalization costs for bronchitis. Controlling CO exposure can be helpful to reduce medical burden associated with bronchitis patients. The results also suggest that when setting air quality standards and formulating preventive measures, susceptible subpopulations ought to be considered.
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Poluentes Atmosféricos , Poluição do Ar , Bronquite , Idoso , Poluentes Atmosféricos/análise , Poluentes Atmosféricos/toxicidade , Poluição do Ar/análise , Bronquite/epidemiologia , Monóxido de Carbono/análise , China/epidemiologia , Exposição Ambiental/análise , Hospitalização , Hospitais , Humanos , Masculino , Material Particulado/análiseRESUMO
Type 2 diabetes (T2DM) as a non-communicable disease imposes heavy disease burdens on society. Limited studies have been conducted to assess the effects of short-term air pollution exposure on T2DM, especially in Asian regions. Our research aimed to determine the association between short-term exposure to ambient nitrogen dioxide (NO2) and outpatient visits for T2DM in Chongqing, the largest city in western China, based on the data collected from November 28, 2013 to December 31, 2019. A generalized additive model (GAM) was applied, and stratified analyses were performed to investigate the potential modifying effects by age, gender, and season. Meanwhile, the disease burden was revealed from attributable risk. Positive associations between short-term NO2 and daily T2DM outpatient visits were observed. The strongest association was observed at lag 04, with per 10 µg/m3 increase of NO2 corresponded to increased T2DM outpatient visits at 1.57% [95% confidence interval (CI): 0.48%, 2.65%]. Stronger associations were presented in middle-aged group (35-64 years old), male group, and cool seasons (October to March). Moreover, there were 1.553% (8664.535 cases) of T2DM outpatient visits attributable to NO2. Middle-aged adults, males, and patients who visited in cool seasons suffered heavier burdens. Conclusively, short-term exposure to NO2 was associated with increased outpatient visits for T2DM. Attention should be paid to the impact of NO2 on the burden of T2DM, especially for those vulnerable groups.
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Poluentes Atmosféricos , Poluição do Ar , Diabetes Mellitus Tipo 2 , Adulto , Poluentes Atmosféricos/análise , Poluentes Atmosféricos/toxicidade , China/epidemiologia , Diabetes Mellitus Tipo 2/induzido quimicamente , Diabetes Mellitus Tipo 2/epidemiologia , Hospitais , Humanos , Masculino , Pessoa de Meia-Idade , Dióxido de Nitrogênio/análise , Dióxido de Nitrogênio/toxicidade , Pacientes Ambulatoriais , Material Particulado/análise , Material Particulado/toxicidadeRESUMO
Atrial fibrillation (AF) is the most common sustained heart rhythm disorder associated with high mortality and morbidity. Limited studies have been conducted to assess the relationship between short-term exposure to ambient air pollution and AF attacks. This study aimed to explore the association between short-term ambient nitrogen dioxide (NO2) exposure and outpatient visits for AF in Xi'an, China. Data on daily AF outpatient visits and air pollutants from 2013 to 2019 (2555 days) were obtained. A time-series approach using over-dispersed Poisson generalized additive model (GAM) was employed, and stratified analyses were performed to investigate the potential modifying effects by season, age, and gender. A total of 8307 outpatient visits for AF were recorded. Increased levels of NO2 were associated with increased AF outpatient visits, and the most significant effect estimates were observed at lag 03: A 10 µg/m3 increase of NO2 at lag 03 was related to an elevation of 5.59% (95% CI: 2.67%, 8.51%) in daily outpatient visits for AF. Stratified analyses showed that there were no gender and age difference in the effect of NO2, while more obvious association was observed in cool seasons (October to March) than in warm seasons (April to September). In summary, short-term ambient NO2 exposure can be positively associated with daily outpatient visits for AF, especially in cool seasons. This work provided novel data that the association between air pollutants and AF can vary by seasons, further supporting that the prevention of cardiovascular health effects should be strengthened in winter.
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Poluentes Atmosféricos , Poluição do Ar , Fibrilação Atrial , Poluentes Atmosféricos/análise , Poluentes Atmosféricos/toxicidade , Poluição do Ar/efeitos adversos , Poluição do Ar/análise , Fibrilação Atrial/induzido quimicamente , Fibrilação Atrial/epidemiologia , China/epidemiologia , Hospitais , Humanos , Dióxido de Nitrogênio/análise , Pacientes Ambulatoriais , Material Particulado/análise , Estações do AnoRESUMO
OBJECTIVE: Bleeding is a severe complication of patients supported with extracorporeal membrane oxygenation (ECMO). This study aimed to analyze the occurrence, risk factors, and clinical outcomes of patients on ECMO with bleeding complications. METHODS: ECMO cases reported to the multicenter ECMO registry database of the Chinese Society of Extracorporeal Life Support (CSECLS) from January 2017 to December 2020 were enrolled. General information, ECMO indications, application, complications, and patient outcomes were collected and analyzed. RESULTS: A total of 6541 ECMO patients from 112 centers were enrolled. Overall, 1185 patients (18.1%) presented with one of the following bleeding complications, including 82 cases (1.3%) with severe bleeding during ECMO catheterization, 462 cases (7.1%) with bleeding at the ECMO cannulation site, 200 cases (3.5%) with bleeding at the surgical site, 180 cases (2.8%) with cerebral hemorrhage, 99 cases (1.5%) with pulmonary hemorrhage, 200 cases (3.5%) with gastrointestinal hemorrhage, 82 cases (1.3%) with ECMO withdrawal, and 118 (1.8%) deaths due to severe bleeding. Extracorporeal cardiopulmonary resuscitation (ECPR) patients had the highest incidence of bleeding complications (22.4%), followed by those on circulatory support (18.7%) and respiratory support (15.4%) (p < 0.001). Multivariate analysis showed that pediatric patients (odds ratio [OR] 1.509, p < 0.001), patients receiving renal replacement therapy (OR 1.932, p < 0.001), and patients receiving central ECMO cannulation (OR 3.023, p < 0.001) were independent risk factors for all bleeding complications, while peripheral cannulation (OR 0.712, p < 0.001) was an independent protective factor. Patients with any bleeding complication had significantly higher in-hospital mortality than patients without (61.9% vs. 46.3%, p < 0.001). CONCLUSION: Up to 18.1% of ECMO patients in the CSECLS registry experienced bleeding complications, which was associated with higher in-hospital mortality, especially in patients who received ECPR, patients on circulatory support, and pediatric patients, which should arouse the attention of clinicians.