A comparison of PM exposure related to emission hotspots in a hot and humid urban environment: Concentrations, compositions, respiratory deposition, and potential health risks

Particle number concentration, particle size distribution, and size-dependent chemical compositions were measured at a bus stop, alongside a high way, and at an industrial site in a tropical city. It was found that the industry case had 4.93 × 107–7.23 × 107 and 3.44 × 104–3.69 × 104 #/m3 higher concentration of particles than the bus stop and highway cases in the range of 0.25–0.65 μm and 2.5–32 μm, respectively, while the highway case had 6.01 × 105 and 1.86 × 103 #/m3 higher concentration of particles than the bus stop case in the range of 0.5–1.0 μm and 5.0–32 μm, respectively. Al, Fe, Na, and Zn were the most abundant particulate inorganic elements for the traffic-related cases, while Zn, Mn, Fe, and Pb were abundant for the industry case. Existing respiratory deposition models were employed to analyze particle and element deposition distributions in the human respiratory system with respect to some potential exposure scenarios related to bus stop, highway, and industry, respectively. It was shown that particles of 0–0.25 μm and 2.5–10.0 μm accounted for around 74%, 74%, and 70% of the particles penetrating into the lung region, respectively. The respiratory deposition rates of Cr and Ni were 170 and 220 ng/day, and 55 and 140 ng/day for the highway and industry scenarios, respectively. Health risk assessment was conducted following the US EPA supplemented guidance to estimate the risk of inhalation exposure to the selected elements (i.e. Cr, Mn, Ni, Pb, Se, and Zn) for the three scenarios. It was suggested that Cr poses a potential carcinogenic risk with the excess lifetime cancer risk (ELCR) of 2.1–98 × 10− 5 for the scenarios. Mn poses a potential non-carcinogenic risk in the industry scenario with the hazard quotient (HQ) of 0.98. Both Ni and Mn may pose potential non-carcinogenic risk for people who are involved with all the three exposure scenarios

Biomass gasification for syngas and biochar co-production: Energy application and economic evaluation

Syngas and biochar are two main products from biomass gasification. To facilitate the optimization of the energy efficiency and economic viability of gasification systems, a comprehensive fixed-bed gasification model has been developed to predict the product rate and quality of both biochar and syngas. A coupled transient representative particle and fix-bed model was developed to describe the entire fixed-bed in the flow direction of primary air. A three-region approach has been incorporated into the model, which divided the reactor into three regions in terms of different fluid velocity profiles, i.e. natural convection region, mixed convection region, and forced convection region, respectively. The model could provide accurate predictions against experimental data with a deviation generally smaller than 10%. The model is applicable for efficient analysis of fixed-bed biomass gasification under variable operating conditions, such as equivalence ratio, moisture content of feedstock, and air inlet location. The optimal equivalence ratio was found to be 0.25 for maximizing the economic benefits of the gasification process

WHEN SHOULD FIRMS BE “OPEN”? THE MODERATING ROLE OF IT COMPETENCY IN INTER-ORGANIZATIONAL OPEN INNOVATION COLLABORATION

Open innovation has gained momentum in recent years. Prior research has shown the critical role of openness in understanding the inter-organizational collaboration process. However, existing studies largely focus on search openness instead of the openness in actual collaboration. In addition, it remains unclear how the new emerged organizational competencies on information technology will shift the role of openness in collaboration. In this study, we investigate the role of collaboration openness in open innovation collaboration and explore the moderating role of information technology competencies. Drawing on the theory of inter-organizational relationship and resource-based view, we examine the conditions under which firms should be “open” in the actual collaboration. We develop hypotheses on network uncertainty, collaboration openness and open innovation performance. The model also incorporates the moderating effects of competitive IT capability and IT intensity. The proposed hypotheses will be tested using firm-level survey and objective data. We also discuss our research method and expected implications

Perioperative aspirin improves neurological outcome after focal brain ischemia possibly via inhibition of Notch 1 in rat

BACKGROUND: Perioperative discontinuation of aspirin is often considered due to bleeding concern. We determined whether this discontinuation affected neurological outcome after brain ischemia. METHODS: Adult male Sprague–Dawley rats were subjected to a 90-minute right middle cerebral arterial occlusion (MCAO). They received 30 mg/kg/day aspirin via gastric gavage: 1) for 2 days at 5 days before MCAO; 2) for 2 days at 5 days before MCAO and for 3 days after MCAO; 3) for 7 days before MCAO; or 4) for 7 days before MCAO and for 3 days after MCAO. Neurological outcome was evaluated 3 days after the MCAO. Ischemic penumbral cortex was harvested 1 or 3 days after MCAO for determining Notch intracellular domain (NICD), IL-6 and IL-1β levels. RESULTS: Aspirin given by regimen 2 and 3 but not by regimen 1 improved neurological outcome. Neuroprotection was achieved by N-[N-(3,5-Difluorophenacetyl)-L-alanyl]-S-phenylglycine t-butyl ester (DAPT), a Notch activation inhibitor. DAPT and aspirin given only by regimen 2 and 3 reduced NICD, IL-6 and IL-1β in the ischemic penumbral cortex. NICD was found in microglial nuclei. Microglial activation in the ischemic tissues was inhibited by aspirin. CONCLUSION: Aspirin use during the perioperative period provides neuroprotection. Inhibition of Notch activation and neuroinflammation may contribute to the neuroprotection of aspirin

Correlation between childhood tuberculosis and abundance of T cell gene transcription and impaired T cell function

Purpose: To investigate the relationship amongst childhood tuberculosis, abundance of T cell gene transcription and impairment of T cell function. Methods: A total of 329 pediatric patients treated for tuberculosis in Central Hospital of Zibo, Zibo, China from 2017 to 2019 were enrolled in the study. Among them, 167 cases of tuberculosis-hospitalized children were assigned to the TB group. Additionally, 162 well- and adequately-treated patients with a previous history of tuberculosis were selected as the control group. The abundance of continuous gene transcripts in the peripheral blood of the children was analyzed. The RNA profiles were analyzed via microarray, while interferon (IFN) level was measured by enzyme linked immunosorbent assay (ELISA). The T cell proliferation was determined by thymidine assay. Results: Within 6 months of the commencement of treatment, the differentially expressed transcripts returned the expression in children in the control group. The abundance of Talipes equinovarus, atrial septal defect, robin sequence, and the persistence of the left superior vena cava (TARP) gene transcription in the TB group was lower than in the control group on days 30, 120 and 180 (p < 0.05), while IL1R2 gene transcription abundance in the TB group was higher than in the control group on days 30, 120 ,180 (p < 0.05). The proliferation of T cells and IFNγ in tuberculosis children (TB group) were lower than in healthy controls (p < 0.05). In this study, a total of 129 genes were found to have significant differences in expression, and hence it is speculated that changes in RNA abundance altered the immune pathway. Conclusion: The reduced abundance of T cell gene transcription and renovated T cell function in children with tuberculosis are related to acquired immunodeficiency. The results of this study provide a theoretical basis for the clinical diagnosis and treatment of tuberculosis in children

Numerical Simulation on Instability Mechanism of Section Coal Pillar in Shallow Buried Coal Seams

There is abundant coal resource of Jurassic period in Yulin City, and the problem of shallow buried coal seams mining will occur in every mine area. FLAC3D is used to analyze the plastic failure, deformation characteristic, and vertical stress on shallow buried coal seams mining, based on north No. 2 engineering geological conditions of Hongliulin Mining Corporation. In this paper, the results are shown as follows. The plastic failure fields of section coal pillar forming are smaller; the coal seam hosting is shallower. The elastic region of section coal pillar has a relatively large proportion, which is the coal seam first mined. The value of Z-Displacement for the first coal seam is relatively small. However, for the lower coal seam it is relatively big. The value of X-Displacement for each coal seam is relatively small. The coal wall of section coal pillar is in a steady state. The coal seam hosting is deeper; the more distant is from coal wall to peak point abutment pressure. The stress concentration factor for the first coal seam is relatively big. The research conclusion reveals instability mechanism of section coal pillar, while coal seams mining, which provides a theoretical basis for designing width vale and optimizing supporting scheme of section coal pillar, has engineering experience application value to other coalmines in Yulin City

Winner Takes All? The “Blockbuster Effect” in Crowdfunding Platforms

Crowdfunding has gained momentum in recent years. Although an increasing amount of research has been devoted to the economic value of crowdfunding, the interactions and effects among crowdfunding projects have yet to be fully studied. The current study strives to bridge this gap by examining the impacts of blockbuster projects — i.e., overwhelmingly successful projects – on the crowdfunding platform. Hypotheses are formulated based on the theory of network effects. Our preliminary results suggest the blockbuster projects exhibit positive spill-over effects within project category but cannibalization effects across categories. We also find evidence of lasting positive/negative network externality within/across category/categories. Further analysis suggests that fresh backers who are attracted to the platform by the blockbuster projects tend to be more engaged and more active. Our research aims to extend the emergent crowdfunding literature by examining network externalities among projects. We also provide practical implications for project creators and platform administrators