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AIM: To determine the associations between the Chinese visceral adiposity index (CVAI) and the risks of all-cause and cause-specific mortality. MATERIALS AND METHODS: A total of 3 916 214 Chinese adults were enrolled in a nationwide population cohort covering all 31 provinces of mainland China. The CVAI was calculated based on age, body mass index, waist circumference, and triglyceride and high-density lipoprotein cholesterol concentrations. We used a Cox proportional hazards regression model to determine the hazard ratios and 95% confidence intervals (CIs) for risk of mortality associated with different CVAI levels. RESULTS: The median follow-up duration was 3.8 years. A total of 86 158 deaths (34 867 cardiovascular disease [CVD] deaths, 29 884 cancer deaths, and 21 407 deaths due to other causes) were identified. In general, after adjusting for potential confounding factors, a U-shaped relationship between CVAI and all-cause mortality was observed by restricted cubic spline (RCS). Compared with participants in CVAI quartile 1, those in CVAI quartile 4 had a 23.0% (95% CI 20.0%-25.0%) lower risk of cancer death, but a 23.0% (95% CI 19.0-27.0) higher risk of CVD death. In subgroup analysis, a J-shaped and inverted U-shaped relationship for all-cause mortality and cancer mortality was observed in the group aged < 60 years. CONCLUSIONS: The CVAI, an accessible indicator reflecting visceral obesity among Chinese adults, has predictive value for all-cause, CVD, and cancer mortality risks. Moreover, the CVAI carries significance in the field of health economics and secondary prevention. In the future, it could be used for early screening purposes.
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Doenças Cardiovasculares , Neoplasias , Adulto , Humanos , Obesidade Abdominal/complicações , Obesidade Abdominal/epidemiologia , Fatores de Risco , Adiposidade , Estudos de Coortes , Causas de Morte , Doenças Cardiovasculares/complicações , China/epidemiologia , Neoplasias/complicaçõesRESUMO
Catalytic oxidation has been considered an effective technique for volatile organic compound degradation. Development of metal foam-based monolithic catalysts coupling electromagnetic induction heating (EMIH) with efficiency and low energy is critical yet challenging in industrial applications. Herein, a Mn18.2-NF monolithic catalyst prepared by electrodeposition exhibited superior toluene catalytic activity under EMIH conditions, and the temperature of 90% toluene conversion decreased by 89 °C compared to that in resistance furnace heating. Relevant characterizations proved that the skin effect induced by EMIH encouraged activation of gaseous oxygen, leading to superior low-temperature redox properties of Mn18.2-NF under the EMIH condition. In situ Fourier transform infrared spectroscopy results showed that skin effect-induced activation of oxidizing species further accelerated the conversion of intermediates. As a result, the Mn18.2-NF monolithic catalyst under EMIH demonstrated remarkable performance for the toluene oxidation, surpassing the conventional nonprecious metal catalyst and other reported monolithic catalysts.
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Óxidos , Tolueno , Tolueno/química , Óxidos/química , Oxirredução , Temperatura , CatáliseRESUMO
The size of support in heterogeneous catalysts can strongly affect the catalytic property but is rarely explored in light-driven catalysis. Herein, we demonstrate the size of TiO2 support governs the selectivity in photothermal CO2 hydrogenation by tuning the metal-support interactions (MSI). Small-size TiO2 loading nickel (Ni/TiO2 -25) with enhanced MSI promotes photo-induced electrons of TiO2 migrating to Ni nanoparticles, thus favoring the H2 cleavage and accelerating the CH4 formation (227.7â mmol g-1 h-1 ) under xenon light-induced temperature of 360 °C. Conversely, Ni/TiO2 -100 with large TiO2 prefers yielding CO (94.2â mmol g-1 h-1 ) due to weak MSI, inefficient charge separation, and inadequate supply of activated hydrogen. Under ambient solar irradiation, Ni/TiO2 -25 achieves the optimized CH4 rate (63.0â mmol g-1 h-1 ) with selectivity of 99.8 %, while Ni/TiO2 -100 exhibits the CO selectivity of 90.0 % with rate of 30.0â mmol g-1 h-1 . This work offers a novel approach to tailoring light-driven catalytic properties by support size effect.
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The position of Ce doping has a significant effect on ambient HCHO storage and catalytic oxidation on layered MnO2. By associating structure and performance, it is unveiled that doping Ce into the in-layered lattice of MnO2 is favorable to the generation of high-valence Mn cations, enhancing the oxidizing ability and capacity, but an opposite influence is displayed by interlayered Ce doping. From the aspect of energy minimization calculated by DFT, in-layered Ce doping is also recommended due to the decreased energies for molecule adsorption and oxygen vacancy formation. As a result, in-layered Ce-doped MnO2 displays exceptional activity in catalyzing the deep oxidation of HCHO and a fourfold higher capacity of ambient HCHO storage than pristine MnO2. The optimal oxide is combined with electromagnetic induction heating to complete the "storage-oxidation" cycle as a promising approach absolutely depending on non-noble oxides and household appliances to realize the long-acting removal of indoor HCHO at room temperature.
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Compostos de Manganês , Óxidos , Óxidos/química , Compostos de Manganês/química , Oxirredução , OxigênioRESUMO
To evaluate corn quality quickly, the feasibility of near-infrared spectroscopy (NIRS) coupled with chemometrics was analyzed to detect the moisture, oil, protein, and starch content in corn. A backward interval partial least squares (BiPLS)-principal component analysis (PCA)-extreme learning machine (ELM) quantitative analysis model was constructed based on BiPLS in conjunction with PCA and the ELM. The selection of characteristic spectral intervals was accomplished by BiPLS. The best principal components were determined by the prediction residual error sum of squares of Monte Carlo cross validation. In addition, a genetic simulated annealing algorithm was utilized to optimize the parameters of the ELM regression model. The established regression models for moisture, oil, protein, and starch can meet the demand for corn component detection with the prediction determination coefficients of 0.996, 0.990, 0.974, and 0.976; the prediction root means square errors of 0.018, 0.016, 0.067, and 0.109; and the residual prediction deviations of 15.704, 9.741, 6.330, and 6.236, respectively. The results show that the NIRS rapid detection model has higher robustness and accuracy based on the selection of characteristic spectral intervals in conjunction with spectral data dimensionality reduction and nonlinear modeling and can be used as an alternative strategy to detect multiple components in corn rapidly.
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As a common food raw material in daily life, the quality and safety of wheat flour are directly related to people's health. In this study, a model was developed for the rapid identification and detection of three illegal additives in flour, namely azodicarbonamide (ADA), talcum powder, and gypsum powder. This model utilized a combination of near-infrared spectroscopy with chemometric methods. A one-dimensional convolutional neural network was used to reduce data dimensionality, while a support vector machine was applied for non-linear classification to identify illegal additives in flour. The model achieved a calibration set F1 score of 99.38% and accuracy of 99.63%, with a validation set F1 score of 98.81% and accuracy of 98.89%. Two cascaded wavelength selection methods were introduced: The first method involved backward interval partial least squares (BiPLS) combined with an improved binary particle swarm optimization algorithm (IBPSO). The second method utilized the CARS-IBPSO algorithm, which integrated competitive adaptive reweighted sampling (CARS) with IBPSO. The two cascade wavelength selection methods were used to select feature wavelengths associated with additives and construct partial least squares quantitative detection models. The models constructed using CARS-IBPSO selected feature wavelengths for detecting ADA, talcum powder, and gypsum powder exhibited the highest overall performance. The model achieved validation set determination coefficients of 0.9786, 0.9102, and 0.9226, with corresponding to root mean square errors of 0.0024%, 1.3693%, and 1.6506% and residual predictive deviations of 6.8368, 3.5852, and 3.9253, respectively. Near-infrared spectroscopy in combination with convolutional neural network dimensionality reduction and support vector machine classification enabled rapid identification of various illegal additives. The combination of CARS-IBPSO feature wavelength selection and partial least squares regression models facilitated rapid quantitative detection of these additives. This study introduces a new approach for rapidly and accurately identifying and detecting illegal additives in flour.
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Farinha , Espectroscopia de Luz Próxima ao Infravermelho , Triticum , Farinha/análise , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Triticum/química , Análise dos Mínimos Quadrados , Quimiometria/métodos , Aditivos Alimentares/análise , Máquina de Vetores de Suporte , Redes Neurais de Computação , Sulfato de Cálcio/química , Sulfato de Cálcio/análise , Talco/análise , Talco/química , AlgoritmosRESUMO
The relationship of ozone (O3), particularly the long-term exposure, with impacting metabolic homeostasis in population was understudied and under-recognised. Here, we used data from ChinaHEART, a nationwide, population-based cohort study, combined with O3 and PM2.5 concentration data with high spatiotemporal resolution, to explore the independent association of exposure to O3 with the prevalence of insulin resistance (IR). Among the 271 540 participants included, the crude prevalence of IR was 39.1%, while the age and sex standardized prevalence stood at 33.0%. Higher IR prevalence was observed with each increase of 10.0 µg/m3 in long-term O3 exposure, yielding adjusted odds ratios (OR) of 1.084 (95% CI: 1.079-1.089) in the one-pollutant model and 1.073 (95% CI: 1.067-1.079) in the two-pollutant model. Notably, a significant additive interaction between O3 and PM2.5 on the prevalence of IR was observed (P for additive interaction < 0.001). Our main findings remained consistent and robust in the sensitivity analyses. Our study suggests long-term exposure to O3 was independently and positively associated with prevalence of IR. It emphasized the benefits of policy interventions to reduce O3 and PM2.5 exposure jointly, which could ultimately alleviate the health and economic burden related to DM.
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Poluentes Atmosféricos , Exposição Ambiental , Resistência à Insulina , Ozônio , Ozônio/toxicidade , Ozônio/análise , Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Poluentes Atmosféricos/toxicidade , Poluentes Atmosféricos/análise , China/epidemiologia , Adulto , Estudos de Coortes , Material Particulado/toxicidade , Idoso , PrevalênciaRESUMO
Background: The triglyceride-glucose (TyG) index has been recognized as a crucial risk factor for cardiovascular diseases. However, the association between the TyG index and mortality in the general population remains elusive. Methods: Participants were enrolled from the China Health Evaluation And risk Reduction through nationwide Teamwork (ChinaHEART), a nationwide prospective cohort study. The outcomes of interest were all-cause, cardiovascular, and cancer mortality. Restricted cubic splines and Cox regression models were used to assess the associations between the TyG index and outcomes. Findings: In total, 3,524,459 participants with a median follow-up of 4.6 (IQR, 3.1-5.8) years were included. The associations of the TyG index with all-cause and cardiovascular mortality were reverse L-shaped, with cut-off values of 9.75 for all-cause mortality and 9.85 for cardiovascular mortality. For each 1-unit increase in the TyG index, when below the cut-off values, the TyG index was not significantly associated with all-cause mortality (HR = 1.02, 95% CI: 1.00-1.03) and was only modestly associated with cardiovascular mortality (HR = 1.09, 95% CI: 1.06-1.11). Conversely, when the cut-off values were exceeded, the HRs (95% CI) were 2.10 (1.94-2.29) for all-cause mortality and 1.99 (1.72-2.30) for cardiovascular mortality. However, the association between the TyG index and cancer mortality was linearly negative (HR = 0.97, 95% CI: 0.94-0.99). Interpretation: The associations of the TyG index with all-cause and cardiovascular mortality displayed reverse L-shaped patterns, while an elevated TyG index showed a slight negative association with cancer mortality. We suggest that <9.75 could be the optimal TyG index cut-off value among the Chinese general population. Individuals at high risk of mortality might benefit from proper management of a high TyG index. Funding: The National High Level Hospital Clinical Research Funding (2023-GSP-ZD-2, 2023-GSP-RC-01), the Ministry of Finance of China and National Health Commission of China.
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The health significance of triglyceride-rich lipoproteins, also known as remnant cholesterol, has been increasingly recognized. However, evidence of their associations with cause-specific mortality in the general population was previously insufficient. To explore these associations and their heterogeneities across subgroups, a prospective cohort study was conducted including 3,403,414 community-based participants from ChinaHEART, an ongoing government-funded public health program throughout China, from November 2014 through December 2022. The study assessed mortality risk of all-cause mortality, cardiovascular disease (CVD) mortality (including mortality from ischemic heart diseases (IHD), ischemic stroke (IS), and hemorrhagic stroke (HS), separately), and cancer mortality (including lung cancer, stomach cancer, and liver cancer, separately). During the 4-year follow-up, 23,646 individuals died from CVD (including 8807 from IHD, 3067 from IS, and 5190 from HS), and 20,318 from cancer (including 6208 from lung cancer, 3013 from liver cancer, and 2174 from stomach cancer). Compared with individuals with remnant cholesterol <17.9 mg/dL, multivariable-adjusted mortality hazard ratios (HRs) for individuals with remnant cholesterol ≥27.7 mg/dL were 1.03 (1.00-1.05) for all-cause mortality, 1.17 (1.12-1.21) for CVD (1.19 (1.12-1.27) for IHD mortality, and 1.22 (1.09-1.36) for IS mortality), and 0.90 (0.87-0.94) for all-cancer mortality (0.94 (0.87-1.02) for lung cancer, 0.59 (0.53-0.66) for liver cancer, and 0.73 (0.64-0.83) for stomach cancer). In summary, this study revealed a correlation between increased remnant cholesterol levels and an elevated risk of cardiovascular disease mortality, as well as a reduced risk of mortality for certain types of cancer.
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Doenças Cardiovasculares , Neoplasias Hepáticas , Neoplasias Pulmonares , Isquemia Miocárdica , Neoplasias Gástricas , Humanos , Estudos Prospectivos , Colesterol , Isquemia Miocárdica/epidemiologia , PulmãoRESUMO
Evidence of the associations between long-term exposure to PM2.5 and O3 and human blood lipid concentrations is abundant yet inconclusive. Whether clean air policies could improve lipid profiles remains unclear. In total, 2979312 participants from a Chinese nationwide prospective study were included. For cross-sectional analyses, linear mixed-effects models were utilized to assess the associations of pollutants with lipid profiles (TC, LDL-C, TG, HDL-C). For longitudinal analyses, a quasi-experimental design and difference-in-differences models were employed to investigate the impact of China's Clean Air Act. In the cross-sectional analyses, each IQR increase in PM2.5 was associated with 2.49 % (95 % CI: 2.36 %, 2.62 %), 2.51 % (95 % CI: 2.26 %, 2.75 %), 3.94 % (95 % CI: 3.65 %, 4.23 %), and 1.54 % (95 % CI: 1.38 %, 1.70 %) increases in TC, LDL-C, TG, and HDL-C, respectively. For each IQR increase in O3, TC, LDL-C, TG, and HDL-C changed by 1.06 % (95 % CI: 0.95 %, 1.17 %), 1.21 % (95 % CI: 1.01 %, 1.42 %), 1.78 % (95 % CI: 1.54 %, 2.02 %), and -0.63 % (95 % CI: -0.76 %, -0.49 %), respectively. Longitudinal analyses showed that the intervention group experienced greater TC, LDL-C, and HDL-C reductions (1.77 %, 4.26 %, and 7.70 %, respectively). Our findings suggest that clean air policies could improve lipid metabolism and should be implemented in countries with heavy air pollution burdens.
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Doping noble metal and acid functionalization were both valid approaches to facilitate oxidation of chlorobenzene on CeO2-based catalysts, but their promotion effects were influenced by different orders of modification process. Because of strong interaction between metal and support and proper redox nature of CeO2, Pt NPs were re-dispersed into single atoms on CeO2 surface via "ex-solution". Companied with Pt loading, the enhancement of oxidizing ability led to generation of polychlorinated by-products. Herein, CeO2-supported Pt was coated by HSiW chainmail to protect Pt from being exposed to Cl-contained atmosphere, and HSiW coating promoted activation of chlorobenzene. The as-prepared chainmail catalyst of HSiW/Pt/CeO2 displayed a remarkable performance in catalyzing oxidation of chlorobenzene without any dichlorobenzene at realistic condition. By comparison, other catalysts with exposed Pt suffered from production of toxic by-products.
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Cério , Catálise , Clorobenzenos , OxirreduçãoRESUMO
By exploiting the superior adsorption capacity of ultra-stable Y-type zeolite (USY) and accurate input of energy by electromagnetic induction field (EMIF) technique, we successfully designed a highly energy-efficient system to eliminate gaseous toluene a common air pollutant. Pristine USY as adsorbent enriches gaseous toluene by a factor of fifteen, via room-temperature adsorption and then EMIF-driven thermal desorption. This operation model involving intermittent heating and mass transfer saves a lot of energy. Especially during temperature rising, 98.9% electric energy can be saved by the EMIF heating in comparison with conventional furnace approaches. In the bi-functional "adsorption-catalytic oxidation" 1Pt/USY, the concentrated toluene undergoes direct oxidation into CO2 rather than desorption when the EMIF heating starts, so one-step enrichment and mineralization are realized. In addition, the developed bi-functional system operates between adsorption and catalytic decomposition flexibly, which makes it ideal for cleaning VOCs emitted from intermittent sources.
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The acoustic properties of a compound micro-perforated panel (MPP) absorber array are investigated. The absorber array consists of three parallel-arranged MPP absorbers with different cavity depths. A finite element procedure is used to simulate its acoustic behaviors under normal incidence. Experimental studies are carried out to verify the numerical simulations. Due to different reactance matching conditions in the absorber array, strong local resonance occurs and the corresponding local resonance absorption dominates. Compared with single MPP absorber, the absorber array requires lower acoustic resistance for good absorption performance, and the resonance frequencies shift due to inter-resonator interactions. The different acoustic resistance requirement is explained by considering the reduced effective perforation rate of the MPP in the absorber array. The performance of the absorber array varies with the sizes and spatial arrangement of the component absorbers. When the distance between component absorbers is larger than a quarter-wavelength, the above-mentioned parallel absorption mechanism diminishes. In the experimental study, the normal incidence absorption coefficients of a prototype MPP absorber array are tested. The measured results compare well with the numerical predictions. The experimental study also shows that although other absorption mechanisms may exist, dissipation by the MPP is dominant in the MPP absorber array.
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Acústica/instrumentação , Som , Absorção , Simulação por Computador , Desenho de Equipamento , Análise de Elementos Finitos , Modelos Teóricos , Análise Numérica Assistida por Computador , Porosidade , VibraçãoRESUMO
In the pursuit of more effective noise control devices, the cavity backed micro-perforated panel absorber (CBMPPA) is developed in this study. A CBMPPA differs from the conventional micro-perforated panel (MPP) absorber in that the MPP is backed by a trapezoidal cavity, which allows more effective vibroacoustic coupling between the MPP and the cavity. A two-dimensional theoretical model is established and tested both numerically and experimentally. Based on the verified theoretical model, sound absorption performance of a trapezoidal CBMPPA is investigated numerically. Results show that the shape of the backing cavity can significantly alter the sound absorption mechanisms and frequency distribution of overall sound absorption coefficient of the absorber. Further analyses show that acoustic modes that are initially decoupled from the MPP in the rectangular configuration are coupled with the air motion in the MPP, which accounts for the change in absorption pattern of the trapezoidal CBMPPA. By the same token, it also provides the flexibility for tuning the effective absorption range of the absorber. Due to the varying impedance matching conditions, the absorption performance of the trapezoidal CBMPPA exhibits obvious local characteristics over the MPP surface, which contrasts with the spatially uniform absorption in the conventional MPP absorber.
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Low-frequency noise is difficult to deal with by traditional porous material due to its inherent high acoustic impedance. This study seeks to extend the effective range of sound absorption to lower frequencies by filling a low density gas, such as helium, in the porous material. Compared with conventional air-filled absorption material, the helium-filled porous material has a much reduced characteristic impedance; hence, a good impedance matching with pure air becomes more feasible at low frequencies. The acoustic properties of a series of helium-filled porous materials are investigated with a specially designed test rig. The characteristic of the sound propagation in a helium-filled porous material is established and validated experimentally. Based on the measured acoustic properties, the sound absorption performance of a helium-filled absorber (HA) of finite thickness is studied numerically as well as experimentally. For a random incidence field, the HA is found to perform much better than the air-filled absorber at low frequencies. The main advantage of HA lies in the middle range of oblique incidence angles where wave refraction in the absorber enhances sound absorption. The advantage of HA as duct lining is demonstrated both numerically and experimentally.
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Hollow and heterostructured architectures are recognized as an effective approach to improve photocatalytic performance. In this work, ternary TiO2/CdTe/BiOI with hollow structure was constructed via a step-by-step method. In addition, the effect of TiO2 structural regulation and the energy band alignment of BiOI and CdTe quantum dots (CdTe QDs) with TiO2 in TiO2/CdTe/BiOI on photocatalytic dye removal were also studied. The results reveal that the TiO2/CdTe/BiOI heterostructures with hollow substrates exhibit much higher photocatalytic activities than pure TiO2, P25, TiO2/CdTe, and TiO2/BiOI and ternary TiO2/CdTe/BiOI with solid substrates. For TiO2(H)/CdTe/BiOI, several synergistic factors may be responsible for the remarkable visible-light photodegradation performance, such as strong visible-light absorption by BiOI and larger specific surface area.
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A previous theoretical study [L. Huang, J. Acoust. Soc. Am. 119, 2628-2638 (2006)] shows that, in a duct, a simply supported plate covering a side-branch rigid cavity can function effectively as a wave reflector over a broad range of low to medium frequencies. In this study, analytical formulation is extended to the boundary condition of clamped plate, which is easier to implement in practice. The theoretical model is tested experimentally using balsawood, which has a very high stiffness to mass ratio. The spectral peaks and shapes of the measured TL are in agreement with those calculated theoretically, attempts are also made to account for the considerable sound absorption in the rig. Further numerical studies based on the validated model show that, for a uniform plate, the optimal stopband is narrower and the lower band limit is worse than that of the simply supported configuration. However, a wave reflector using nonuniform, clamped plates with thinner ends out-performs the simply supported configuration in every aspect. Analyses show that the improvement is attributed to the increased acoustic radiation efficiency over the bulk length of the nonuniform plate, which behaves more like a rigid plate.