Multimorbidity, body pain, sleep disturbance, and depression are major clinical and public health challenges. This paper aimed to examine the associations of multimorbidity with body pain, sleep ...duration, and depression; and whether the associations varied by socioeconomic status.
Data was derived from four waves of the nationally representative China Health and Retirement Longitudinal Study (CHARLS), including participants aged 45 years and older in 2011. 12 physical non-communicable diseases and 1 mental chronic disease were used to measure multimorbidity. Educational attainment and annual per-capita household consumption expenditure were employed as proxies for socioeconomic status.
Of the 16,931 participants aged 45 + years old, the proportion of people with multimorbidity was 37.87% at baseline. The number of multimorbidity increased with older age and higher socioeconomic status. Multimorbidity was associated with more body pain (incidence rate ratio (IRR) = 1.53, 95% CI = 1.45-1.61), and decreased sleep duration (β = -0.26, 95% CI = -0.36--0.15). Furthermore, multimorbidity was associated with increased depression risks (odds ratio (OR) = 1.54, 95% CI = 1.44-1.64, adjusted for sociodemographic variables), with the mediating effects of the number of body pain and sleep duration. The associations between multimorbidity and depression persisted among different socioeconomic groups.
Multimorbidity was associated with increased body pain, decreased sleep duration, and further led to increased depression risks. It is necessary to pay attention to the multimorbidity of middle-aged and older adults, relieve their body pain, guarantee sufficient sleep, so as to reduce depression risks.
For multi-ceramic materials based on the stereolithography (SL) principle, a 3D printing strategy was developed, and then an Al2O3-Si3N4 functionally graded material (FGM) ceramic part was fabricated ...using this strategy. Six groups of mixtures, with a Si3N4 content gradient of 20 vol% and a certain bimodal particle size distribution, were prepared using UV-curable pastes. A modified formula was proposed to evaluate the relationship between the actual minimum voidage of mixtures and the viscosities of their corresponding pastes. The viscosity of each paste was controlled using the prediction formula and optimization of dispersants. To design theprinting layer thickness, a mathematical relationship was established between Si3N4 content and curing depth of paste. The Al2O3-Si3N4 green body without deformation was printed using optimized parameters such as a layer thickness of 40 μm and a paste viscosity of ∼13,000 mPa·s. Finally, using debinding and sintering, denseparts having a complicated shape were obtained.
Nitrous acid (HONO) is a key reservoir of the hydroxyl radical (OH) and plays a central role in the atmospheric chemistry. To understand the sources and impact of HONO in the polluted atmosphere of ...northern China, continuous measurements of HONO and related parameters were conducted from September 2015 to August 2016 at an urban site in Ji'nan, the capital city of Shandong province. HONO showed well-defined seasonal and diurnal variation patterns with clear wintertime and nighttime concentration peaks. Elevated HONO concentrations (e.g., over 5 ppbv) were frequently observed with a maximum value of 8.36 ppbv. The HONO/NOX ratios of direct vehicle emissions varied in the range of 0.29%–0.87%, with a mean value of 0.53%. An average NO2-to-HONO nighttime conversion frequency (khet) was derived to be 0.0068 ± 0.0045 h−1 from 107 HONO formation cases. A detailed HONO budget analysis suggests an unexplained daytime missing source of 2.95 ppb h−1 in summer, which is about seven times larger than the homogeneous reaction of NO with OH. The effect of HONO on OH production was also quantified. HONO photolysis was the uppermost source of local OH radical throughout the daytime. This study provides the year-round continuous record of ambient HONO in the North China Plain, and offers some insights into the characteristics, sources and impacts of HONO in the polluted atmospheres of China.
•One-year continuous measurements of HONO were made at a typical urban site in northern China.•The variation characteristics and various sources strength of HONO were examined based on a large data set.•A strong missing daytime source was needed to explain the measured HONO concentrations.•HONO photolysis is the dominant OH source throughout the daytime.
•Multi-negative stiffness amplification systems (NSAS) with improved damping effect.•Multi-location NSAS approach developed for complex underground structures.•Dual isolation of a column with a pair ...of NSASs for multi-intensity excitations.•Structural plastic energy dissipation burden significantly relieved by NSAS.•Residual deformation of columns avoided by the isolating ability of NSASs.
Underground structures are vulnerable to strong earthquakes, with their central columns being prone to damage owing to their insufficient resistance capacity. In this study, an effective, hybrid, and multi-location seismic isolation approach was proposed for multi-floor and multi-span underground structures using several negative-stiffness amplification system-based isolation systems (NSAS-ISs). The NSAS-IS originated from the incorporation of an NSAS and an isolation bearing, which was proposed as a flexible connection installed at either the top or bottom of the central columns. The mechanical model as well as physical realization of the NSAS-IS was explored, and an improved damping mechanism was introduced. Subsequently, a multi-location isolation method was proposed with the NSAS-ISs installed at the top or bottom of the columns (corresponding to the 1-end-based isolation method) and at both the top and bottom of the columns (corresponding to the 2-end-based isolation method). The effectiveness and robustness of the proposed NSAS-IS pertaining to the structural seismic response mitigation of typical underground structures under different isolation methods were investigated, focusing on the underground structures buried at different depths subject to various seismic excitations at multiple intensities. The obtained results indicated the effectiveness of both the 1-end- and 2-end-based isolation methods for NSAS-IS in improving the seismic performance of multi-floor and multi-span underground structures, with significant improvement being observed in the damping and isolation effects. In particular, the 2-end isolation method was found to be considerably effective in multi-performance control for multi-intensity excitations and is thus suggested for underground structures with limited space for installation and isolation layers. Consequently, the plastic energy-dissipation burden of the primary structures can be significantly relieved, and the residual deformation of the columns can be avoided owing to their excellent isolation ability.
A novel transition-metal-free cascade reaction to synthesize 4-quinolone derivatives has been demonstrated. Michael addition and Truce-Smiles rearrangement are included in this protocol, providing a ...broad scope of 4-quinolones in moderate-to-excellent yields. This work serves as an example of the use of sulfonamides through Truce–Smiles rearrangement to build heterocyclic compounds under mild conditions.
Secondary inorganic aerosols play important roles in visibility reduction and in regional haze pollution. To investigate the characteristics of size distributions of secondary sulfates and nitrates ...as well as their formation mechanisms under hazes, size-resolved aerosols were collected using a Micro-Orifice Uniform Deposit Impactor (MOUDI) at an urban site in Jinan, China, in all four seasons (December 2007–October 2008). In haze episodes, the secondary sulfates and nitrates primarily formed in fine particles, with elevated concentration peaks in the droplet mode (0.56–1.8 μm). The fine sulfates and nitrates were completely neutralized by ammonia and existed in the forms of (NH4)2SO4 and NH4NO3, respectively. The secondary formation of sulfates, nitrates and ammonium (SNA) was found to be related to heterogeneous aqueous reactions and was largely dependent on the ambient humidity. With rising relative humidity, the droplet-mode SNA concentration, the ratio of droplet-mode SNA to the total SNA, the fraction of SNA in droplet-mode particles and the mass median aerodynamic diameter of SNA presented an exponential, logarithmic or linear increase. Two heavily polluted multi-day haze episodes in winter and summer were analyzed in detail. The secondary sulfates were linked to heterogeneous uptake of SO2 followed by the subsequent catalytic oxidation by oxygen together with iron and manganese in winter. The fine nitrate formation was strongly associated with the thermodynamic equilibrium among NH4NO3, gaseous HNO3 and NH3, and showed different temperature-dependences in winter and summer.
► Size-resolved inorganic aerosol compositions were analyzed for a highly polluted area. ► Humidity-dependent heterogeneous formation of inorganic aerosols was investigated. ► Relationships were given between the SO42−, NO3−, NH4+ in the droplet mode and the RH. ► Dominant formation pathways of sulfates and nitrates were analyzed for haze events.
Nitrated phenols are a major class of brown carbon in the atmosphere and have adverse effects on human and plants health. They are emitted from combustion sources or produced by oxidation of phenolic ...precursors. In this study, fine particulates, total suspended particulates, and gas-phase samples were collected in urban Jinan in winter, spring, and summer, and UHPLC-MS analysis was used to determine 8 phenolic compounds and 12 nitrated phenols in these samples. The seasonal average concentrations of total phenolic compounds and total nitrated phenols were in the ranges of 2.6–18.7 ng m−3 and 13.5–105.4 ng m−3, respectively. The concentrations of phenolic compounds and nitrated phenols were highest in winter, followed (in decreasing order) by spring, and summer. Phenol and salicylic acid were the most abundant phenolic species in both gaseous and particulate samples. 4-Nitrophenol was the most abundant nitrated phenols in particulate matters, followed by 4-nitrocatechol and 5-nitrosalicylic acid, while 4-nitrophenol and 2,4-dinitrophenol were the dominant species in the gas phase. The distributions of phenolic compounds and nitrated phenols in fine and coarse particles and in gas and particle phases were largely dependent on the aerosol size distribution, the ambient temperature, and the compound volatility. More of them were distributed in fine particles and gas-phase in summer than in spring. It was found that phenol, catechol, methyl-catechols, 4-nitrophenol, and methyl-nitrophenols mainly derived from coal combustion, while biomass burning was the main source of cresols, 2,6-dimethyl-4-nitrophenol, 4-nitrocatechol, and methyl-nitrocatechols. In addition, secondary formation contributed the largest fraction of nitrosalicylic acids and vehicle exhaust was the major source of cresols, 2,6-dimethyl-4-nitrophenol, and 4-methyl-2,6-dinitrophenol. Further correlation analysis revealed positive correlations between nitrated phenols and corresponding phenolic precursors, indicating the important roles that phenolic precursors played in the secondary formation and abundance of nitrated phenols in the atmosphere.
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•Gas-and particle-phase phenols and nitrated phenols were measured in three seasons.•Phenol, salicylic acid, 4-nitrophenol, and 4-nitrocatechol were dominant species.•More phenols and nitrated phenols appeared in fine particles and gas phase in summer.•Four sources were identified and the contributions varied with species and seasons.•Phenolic precursors promoted the formation of nitrated phenols especially in summer.
Nitrated phenols (NPs) are regarded as a major component of brown carbon and affect the earth environment. Previous studies have suggested that NPs in the atmosphere partially originate from coal ...combustion; however, the direct emissions have not been validated. In this study, the emissions of ten NPs from ten kinds of coal for residential use were investigated via laboratory combustion experiments in which PM2.5 samples were collected and analyzed by UHPLC-MS. The fine particulate NPs emitted from coal combustion were dominated by nitrocatechols and the methyl substituents under most conditions, while the emission profile of nitrated phenols varies with different rank of coals. Based on the emission ratios of NPs/PM2.5 obtained from this study and the PM2.5 emission factors in the literature, the emission factors of fine particulate NPs for chunks of lignite, bituminite, and anthracite and for briquettes of anthracite were calculated as 0.2–10.1 mg kg−1. According to the residential coal consumption in 30 provinces in China in 2016, the total emission of fine particulate NPs from the residential coal combustion was estimated to be 178 ± 42 Mg.
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•Emission profile of nitrated phenols varies with coal maturity and combustion stage.•Emission factor of nitrated phenols decreases with the increasing rank of coal.•Emission of nitrated phenols from residential coal combustion in China was estimated.
This study investigated the particle size‐ and age‐dependent mixing structures of individual particles in clean and polluted air. Aerosols were classified into eight components: sea salt, mineral ...dust, fly ash, metal, soot, sulfates, nitrates, and organic matter (OM). Based on our aerosol classification, a particle that consists of two or more aerosol components can be defined as an internally mixed particle. Otherwise, it is considered to be an externally mixed particle. Within the internally mixed particle class, we identified four heterogeneous mixing structures: core‐shell, dumbbell, OM coating, and dispersed OM, as well as one homogeneous‐like mixing structure. Homogeneous‐like mixing mainly occurred in fine particles (<1 µm), while the frequency of heterogeneously mixed particles increased with particle size. Our study demonstrated that particle mixing structures depend on particle size and location and evolve with time. OM‐coating and core‐shell structures are important indicators for particle aging in air as long as they are distant from specific emission sources. Long‐range transported particles tended to have core‐shell and OM‐coating structures. We found that secondary aerosol components (e.g., sulfates, nitrates, and organics) determined particle mixing structures, because their phases change following particle hydration and dehydration under different relative humidities. Once externally mixed particles are transformed into internally mixed particles, they cannot revert to their former state, except when semivolatile aerosol components are involved. Categorizing mixing structures of individual particles is essential for studying their optical and hygroscopic properties and for tracing the development of their physical or chemical properties over time.
Key Points
Our study systematically identifies mixing structures within internally mixed particles
Particle mixing structures depend on particle size and location and they evolve over time
Secondary aerosol formation mainly determined particle mixing structures in this study
Zhongfenggao (ZFG) is prescribed for the treatment of cerebrovascular diseases in critical projects of the State Administration of Traditional Chinese Medicine. ZFG has been found to nourish qi, ...activate blood circulation, remove blood stasis, dredge collaterals, and strengthen the brain and mind. The present study investigated the effects of ZFG on oxygen–glucose deprivation–reoxygenation (OGD/R) induced injury to brain microvascular endothelial cells (BMECs), and the mechanisms underlying such effects. BMECs are essential target cells of ischemic stroke. In order to simulate ischemic-like conditions in vitro, BMECs were exposed to glucose deprivation and hypoxia for 2 h. Results indicate that ZFG may protect OGD/R-induced injury to BMECs by promoting angiogenesis. Further, we observed that ZFG significantly inhibited apoptosis induced by OGD/R injury. ZFG significantly promoted migration and microtubule formation in BMECs under OGD/R conditions. Additionally, ZFG increased levels of the vascular endothelial growth factor (VEGF) significantly and activated the Notch and Wnt signaling pathways. The results of the present study indicate that ZFG may display a protective effect against OGD/R-induced BMECs injury by promoting angiogenesis via Notch and Wnt signaling pathways. These results provide novel insights into the mechanisms underlying the therapeutic action of ZFG which shows promise as a potential drug candidate for treating cerebral ischemia–reperfusion.
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