The mitigation of air pollution in megacities remains a great challenge because of the complex sources and formation mechanisms of aerosol particles. The 2014 Asia-Pacific Economic Cooperation (APEC) ...summit in Beijing serves as a unique experiment to study the impacts of emission controls on aerosol composition, size distributions, and oxidation properties. Herein, a high-resolution time-of-flight aerosol mass spectrometer was deployed in urban Beijing for real-time measurements of size-resolved non-refractory submicron aerosol (NR-PM1) species from 14 October to 12 November 2014, along with a range of collocated measurements. The average (±σ) PM1 was 41.6 (±38.9) μg m−3 during APEC, which was decreased by 53 % compared with that before APEC. The aerosol composition showed substantial changes owing to emission controls during APEC. Secondary inorganic aerosol (SIA: sulfate + nitrate + ammonium) showed significant reductions of 62–69 %, whereas organics presented much smaller decreases (35 %). The results from the positive matrix factorization of organic aerosol (OA) indicated that highly oxidized secondary organic aerosol (SOA) showed decreases similar to those of SIA during APEC. However, primary organic aerosol (POA) from cooking, traffic, and biomass-burning sources were comparable to those before APEC, indicating the presence of strong local source emissions. The oxidation properties showed corresponding changes in response to OA composition. The average oxygen-to-carbon level during APEC was 0.36 (±0.10), which is lower than the 0.43 (±0.13) measured before APEC, demonstrating a decrease in the OA oxidation degree. The changes in size distributions of primary and secondary species varied during APEC. SIA and SOA showed significant reductions in large accumulation modes with peak diameters shifting from ~ 650 to 400 nm during APEC, whereas those of POA remained relatively unchanged. The changes in aerosol composition, size distributions, and oxidation degrees during the aging processes were further illustrated in a case study of a severe haze episode. Our results elucidated a complex response of aerosol chemistry to emission controls, which has significant implications that emission controls over regional scales can substantially reduce secondary particulates. However, stricter emission controls for local source emissions are needed for further mitigating air pollution in the megacity of Beijing.
Prefabricated construction has been used for public rental housing in Hong Kong. In order to speed up housing delivery, Hong Kong Housing Authority (HKHA) have employed advanced technologies, ...including Building Information Modelling (BIM) and Radio Frequency Identification (RFID), in some of their pilot prefabrication-based construction projects. However, the information obtained from BIM and RFID is not well connected and shared among relevant stakeholders. This paper introduces a multi-dimensional Internet of Things (IoT)-enabled BIM platform (MITBIMP) to achieve real-time visibility and traceability in prefabricated construction. Design considerations of a RFID Gateway Operating System, visibility and traceability tools, Data Source Interoperability Services, and decision support services are specified for developing the MITBIMP. A case study from a real-life construction project in Hong Kong is used as a pilot project to demonstrate advanced decision-making by using cutting-edge concepts and technologies within the MITBIMP to providing a basis for real-time visibility and traceability of the whole processes of prefabrication-based construction.
•The study extends 3D BIM application into nD by using IoT-enabled tools.•A framework of the nD BIM platform has been established.•nD system is to facilitate prefabricated construction by visualized services.•A case study has been used to demonstrate the usefulness of the platform.
Brain-derived neurotrophic factor (BDNF) is expressed in nociceptive sensory neurons and transported anterogradely to the dorsal horn of the spinal cord where it is located in dense core vesicles in ...C-fiber terminals. Peripheral inflammation substantially up-regulates BDNF mRNA and protein in the dorsal root ganglion (DRG) in a nerve growth factor-dependent fashion and results in novel expression of BDNF by DRG neurons with myelinated axons. C-fiber electrical activity also increases BDNF expression in the DRG, and both inflammation and activity increase full-length TrkB receptor levels in the dorsal horn. Sequestration of endogenous BDNF/neurotrophin 4 by intraspinal TrkB-Fc fusion protein administration does not, in noninflamed animals, change basal pain sensitivity nor the mechanical hypersensitivity induced by peripheral capsaicin administration, a measure of C fiber-mediated central sensitization. TrkB-Fc administration also does not modify basal inflammatory pain hypersensitivity, but does block the progressive hypersensitivity clicited by low-intensity tactile stimulation of inflamed tissue. BDNF, by virtue of its nerve growth factor regulation in sensory neurons including novel expression in A fibers, has a role as a central modulator of tactile stimulus-induced inflammatory pain hypersensitivity.
Pavement maintenance is widely thought to be critical for promoting their sustainability. It plays a pivotal role in sustainable and resilient transportation infrastructure for economic development ...and social inclusion improvement. Existing research mainly focuses on optimizing the maintenance strategies based on one player but ignores the inherent conflicts and complex interactions among multiplayer decision-makers. To address these issues, this research examined the problem of pavement maintenance involving the highway agency and maintenance service providers under the uncertainty of pavement conditions with the aim of optimizing maintenance strategies. A novel bilevel mathematical model was proposed to handle the inherent conflicts and complex interactions among decision-makers based on the Stackelberg game and Nash game. The goal is to obtain the Stackelberg–Nash equilibrium solution, where the highway agency, as the upper-level leader, determines the maintenance tasks, whereas the service providers, as the lower-level followers, provide the corresponding maintenance activities. To formulate this complex model, a bilevel particle swarm optimization (BLPSO) algorithm was developed for pavement maintenance. Finally, a practical case was used to demonstrate the practicality and efficiency of the proposed model. The results show that the mathematical model can provide feasible and effective pavement maintenance strategies for multiplayer decision-makers in real-world applications.
•A bilevel mathematical model is proposed for dynamic long-term pavement maintenance.•Bilevel multiple decision-makers using the Stackelberg–Nash game are incorporated.•A BLPSO algorithm is developed to obtain an equilibrium maintenance strategy.•Comparative results show a significant profit increment for each decision-maker.•The model is feasible and effective for optimizing multiplayer pavement maintenance.
Explore the mental health status and its influencing factors of local community residents under the post-epidemic era of coronavirus disease 2019 (COVID-19) in China.
The basic information scale, ...self-rating depression scale and self-rating anxiety scale were used to carry out an online questionnaire survey among community residents in Jiangsu Province, China, and the influencing factors of depression and anxiety were analyzed by multivariate logistic regression.
A total of 993 residents completed the mental health survey. It was found that the incidence of depressive and anxiety symptoms was 37.06% and 22.86%. Multivariate logistic regression analysis showed that women odds ratio (OR) 95% confidence interval (95% CI) = 26.239 (14.743-46.698), college degree and above OR (95% CI) = 1.843 (1.085-3.130) and ordinary residents OR (95% CI) = 2.222 (1.441-3.425) were risk factors for depressive symptoms, urban residents had lower risk OR (95% CI) = 0.655 (0.394-0.829). Women OR (95% CI) = 33.595 (15.812-71.381) and ordinary residents OR (95% CI) = 3.017 (1.602-5.680) were risk factors for anxiety symptoms while the incidence was reduced in professional and technical personnel OR (95% CI) = 0.271 (0.123-0.597), workers OR (95% CI) = 0.383 (0.168-0.876), soldiers or policemen OR (95% CI) = 0.200 (0.042-0.961), married residents OR (95% CI) = 0.463 (0.230-0.931) and urban residents OR (95% CI) = 0.531 (0.251-0.824).
The incidence of symptoms of depression and anxiety among residents was relatively high under the post-epidemic era of COVID-19, which could be affected by various factors.
The Brazilian test is a widely used method for determining the tensile strength of rocks and for calibrating parameters in bonded-particle models (BPMs). In previous studies, the Brazilian disc has ...typically been trimmed from a compacted rectangular specimen. The present study shows that different tensile strength values are obtained depending on the compressive loading direction. Several measures are proposed to reduce the anisotropy of the disc. The results reveal that the anisotropy of the disc is significantly influenced by the compactibility of the specimen from which it is trimmed. A new method is proposed in which the Brazilian disc is directly generated with a particle boundary, effectively reducing the anisotropy. The stiffness (particle and bond) and strength (bond) of the boundary are set at less than and greater than those of the disc assembly, respectively, which significantly decreases the stress concentration at the boundary contacts and prevents breakage of the boundary particle bonds. This leads to a significant reduction in the anisotropy of the disc and the discreteness of the tensile strength. This method is more suitable for carrying out a realistic Brazilian test for homogeneous rock-like material in the BPM.
It is well established that the tumor suppressor p53 plays major roles in regulating apoptosis and cell cycle progression. In addition, recent studies have demonstrated that p53 is actively involved ...in regulating cell differentiation in muscle, the circulatory system and various carcinoma tissues. We have recently shown that p53 also controls lens differentiation. Regarding the mechanism, we reveal that p53 directly regulates c-Maf and Prox1, two important transcription factors to control cell differentiation in the ocular lens. In the present study, we present further evidence to show that p53 can regulate lens differentiation by controlling expression of the differentiation genes coding for the lens crystallins. First, the αA and βA3/A1 gene promoters or introns all contain putative p53 binding sites. Second, gel mobility shifting assays revealed that the p53 protein in nuclear extracts from lens epithelial cells directly binds to the p53 binding sites found in these crystallin gene promoters or introns. Third, exogenous wild type p53 induces dose-dependent expression of the luciferase reporter gene driven by different crystallin gene promoters and the exogenous dominant negative mutant p53 causes dose-dependent inhibition of the same crystallin genes. Fourth, ChIP assays revealed that p53 binds to crystallin gene promoters in vivo. Finally, in the p53 knockout mouse lenses, expression levels of various crystallins were found down-regulated in comparison with those from the wild type mouse lenses. Together, our results reveal that p53 directly regulates expression of different sets of genes to control lens differentiation.
OBJECTIVETo understand the relationship between health literacy and patient experience of outpatients in China, and to explore its mechanism. METHODSThe conceptual framework was developed based on ...Andersen's behavioral model of health services use and health literacy skills framework. An online cross-sectional survey was conducted with snowball sampling method, while the health literacy was measured by self-designed patient health literacy scale, and the patient experience was measured by the Chinese patient experience questionnaire for ambulatory care developed by Peking Union Medical College. And a structural equation model was built to explore the relationship between them and test the mechanism of health literacy influencing patient experience. RESULTSA total of 2 773 subjects were investigated. The average score of health literacy was (90.72±12.90) points, accounting for 78.89% of the full score, and the dimension of seeking social support had the lowest score. The average score of overall rating of pati
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