35 research outputs found
Moral Hazard and Transparency in Peer-to-Peer Auto Insurance with Telematics
Peer-to-peer (P2P) insurance uses new technology to connect policyholders and brings about disruptive innovation. While P2P insurance serving people with relatively high degrees of social connection, like friends and relatives, has been theoretically and practically underpinned, there is a lack of understanding about its viability or efficiency in serving strangers with few to no social ties as moral hazard may be substantial. In this paper, we bridge the gap by empirically measuring moral hazard in a P2P auto insurance where the insured individuals are strangers. Our research findings remove an obstacle that may hinder a broad application of the P2P insurance model among large groups of individuals. Moreover, we investigate factors that mitigate moral hazard and study the impact of transparency in premium balance on driving safety. We show that the transparency allows people to learn vicariously from peers’ lessons and lets them drive more safely
Neutrophil-to-lymphocyte ratio as an independent risk factor for mortality in hospitalized patients with COVID-19
Background:
Several studies have described the clinical characteristics of patients with novel coronavirus (SARS-CoV-2) infected pneumonia (COVID-19), indicating severe patients tended to have higher neutrophil to lymphocyte ratio (NLR). Whether baseline NLR could be an independent predictor of in-hospital death in Chinese COVID-19 patients remains to be investigated.
Methods:
A cohort of patients with COVID-19 admitted to the Zhongnan Hospital of Wuhan University from January 1 to February 29 was retrospectively analyzed. The baseline data of laboratory examinations, including NLR, were collected. Univariate and multivariate logistic regression models were developed to assess the independent relationship between the baseline NLR and in-hospital all-cause death. A sensitivity analysis was performed by converting NLR from a continuous variable to a categorical variable according to tertile. Interaction and stratified analyses were conducted as well.
Results:
245 COVID-19 patients were included in the final analyses, and the in-hospital mortality was 13.47%. Multivariate analysis demonstrated that there was 8% higher risk of in-hospital mortality for each unit increase in NLR (Odds ratio [OR] = 1.08; 95% confidence interval [95% CI], 1.01 to 1.14; P = 0.0147). Compared with patients in the lowest tertile, the NLR of patients in the highest tertile had a 15.04-fold higher risk of death (OR = 16.04; 95% CI, 1.14 to 224.95; P = 0.0395) after adjustment for potential confounders. Notably, the fully adjusted OR for mortality was 1.10 in males for each unit increase of NLR (OR = 1.10; 95% CI, 1.02 to 1.19; P = 0.016).
Conclusions:
NLR is an independent risk factor of the in-hospital mortality for COVID-19 patients especially for male. Assessment of NLR may help identify high risk individuals with COVID-19
Device-measured movement behaviours in over 20,000 China Kadoorie Biobank participants
Background: Movement behaviours, including physical activity, sedentary behaviour, and sleep have been shown to be associated with several chronic diseases. However, they have not been objectively measured in large-scale prospective cohort studies in low-and middle-income countries. We aim to describe the patterns of device-measured movement behaviours collected in the China Kadoorie Biobank (CKB) study.
Methods: During 2020 and 2021, a random subset of 25,087 surviving CKB individuals participated in the 3rd resurvey of the CKB. Among them, 22,511 (89.7%) agreed to wear an Axivity AX3 wrist-worn triaxial accelerometer for seven consecutive days to assess their habitual movement behaviours. We developed a machine-learning model to infer time spent in four movement behaviours [i.e. sleep, sedentary behaviour, light intensity physical activity (LIPA), and moderate-to-vigorous physical activity (MVPA)]. Descriptive analyses were performed for wear-time compliance and patterns of movement behaviours by different participant characteristics.
Results: Data from 21,897 participants (aged 65.4 ± 9.1 years; 35.4% men) were received for demographic and wear-time analysis, with a median wear-time of 6.9 days (IQR: 6.1–7.0). Among them, 20,370 eligible participants were included in movement behavior analyses. On average, they had 31.1 mg/day (total acceleration) overall activity level, accumulated 7.7 h/day (32.3%) of sleep time, 8.8 h/day (36.6%) sedentary, 5.7 h/day (23.9%) in light physical activity, and 104.4 min/day (7.2%) in moderate-to-vigorous physical activity. There was an inverse relationship between age and overall acceleration with an observed decline of 5.4 mg/day (17.4%) per additional decade. Women showed a higher activity level than men (32.3 vs 28.8 mg/day) and there was a marked geographical disparity in the overall activity level and time allocation.
Conclusions: This is the first large-scale accelerometer data collected among Chinese adults, which provides rich and comprehensive information about device-measured movement behaviour patterns. This resource will enhance our knowledge about the potential relevance of different movement behaviours for chronic disease in Chinese adults
Macrophage-Stimulated Cardiac Fibroblast Production of IL-6 Is Essential for TGF β/Smad Activation and Cardiac Fibrosis Induced by Angiotensin II
Interleukin-6 (IL-6) is an important cytokine participating in multiple biologic activities in immune regulation and inflammation. IL-6 has been associated with cardiovascular remodeling. However, the mechanism of IL-6 in hypertensive cardiac fibrosis is still unclear. Angiotensin II (Ang II) infusion in mice increased IL-6 expression in the heart. IL-6 knockout (IL-6-/-) reduced Ang II-induced cardiac fibrosis: 1) Masson trichrome staining showed that Ang II infusion significantly increased fibrotic areas of the wild-type mouse heart, which was greatly suppressed in IL-6-/- mice and 2) immunohistochemistry staining showed decreased expression of α-smooth muscle actin (α-SMA), transforming growth factor β1 (TGF-β1) and collagen I in IL-6-/- mouse heart. The baseline mRNA expression of IL-6 in cardiac fibroblasts was low and was absent in cardiomyocytes or macrophages; however, co-culture of cardiac fibroblasts with macrophages significantly increased IL-6 production and expression of α-SMA and collagen I in fibroblasts. Moreover, TGF-β1 expression and phosphorylation of TGF-β downstream signal Smad3 was stimulated by co-culture of macrophages with cardiac fibroblasts, while IL-6 neutralizing antibody decreased TGF-β1 expression and Smad3 phosphorylation in co-culture of macrophage and fibroblast. Taken together, our results indicate that macrophages stimulate cardiac fibroblasts to produce IL-6, which leads to TGF-β1 production and Smad3 phosphorylation in cardiac fibroblasts and thus stimulates cardiac fibrosis
Spatiotemporal exploration of the non-linear impacts of accessibility on metro ridership
Identifying the determinants of metro ridership is essential for metro planning and passenger flow management. However, few studies to date have empirically examined how accessibility affects metro ridership and even fewer have emphasized the non-linear impacts from a spatiotemporal perspective. This study demarcates station areas via the network-distance method and precisely quantifies the accessibility of metro stations both internally and externally. This is combined with a gradient boosting regression trees (GBRT) model and a Shapley additive explanations (SHAP) model to understand the non-linear impacts of accessibility on metro ridership from a spatiotemporal perspective. The results show that accessibility indicators collectively contribute more than 60% of the predictive power for metro ridership at different times and the external accessibility has a greater impact on metro ridership than internal accessibility. Some indicators, such as the shortest path and population density show threshold effects on metro ridership. More importantly, the results demonstrate significant spatial heterogeneity in the effects of accessibility indicators on metro ridership and geographic trends generally from urban to suburban areas. The findings are expected to help planning departments and transit agencies improve the coordinated development of metro systems
Cascading failure and recovery of metro–bus double-layer network considering recovery propagation
Normal operation of metros and buses is essential for sustainable urban development. Studies have shown that a disaster occurring on one transport station leads to the cascading failure of transportation networks, but the functions will be restored successively after post-disaster repairs. However, most studies have focused on cascading failures, ignoring the impact of recovery propagation. Therefore, this study proposes a cascading failure and recovery model to illustrate the evolution process of a metro–bus double-layer network considering recovery propagation and investigates factors including failure and recovery spreading mechanisms, different initial loads, node capacities, and repair speeds. The proposed model is applied to an actual case study of Xi’an City under different scenarios. The effects of node capacity and repair speed exhibit a marginal decreasing trend. The coexistence of cascading failure and recovery propagation enhances network minimum performance. This study has implications for strategic development of sustainable and stable transportation systems
Efficient Activation of Peroxymonosulfate by Biochar-Loaded Zero-Valent Copper for Enrofloxacin Degradation: Singlet Oxygen-Dominated Oxidation Process
The removal of contaminants of emerging concern (CECs) has become a hot research topic in the field of environmental engineering in recent years. In this work, a simple pyrolysis method was designed to prepare a high-performance biochar-loaded zero-valent copper (CuC) material for the catalytic degradation of antibiotics ENR by PMS. The results showed that 10 mg/L of ENR was completely removed within 30 min at an initial pH of 3, CuC 0.3 g/L, and PMS 2 mmol/L. Further studies confirmed that the reactive oxygen species (ROS) involved in ENR degradation are ·OH, SO4−·, 1O2, and O2−. Among them, 1O2 played a major role in degradation, whereas O2−· played a key role in the indirect generation of 1O2. On the one hand, CuC adsorbed and activated PMS to generate ·OH, SO4−· and O2−·. O2−· was unstable and reacted rapidly with H2O and ·OH to generate large amounts of 1O2. On the other hand, both the self-decomposition of PMS and direct activation of PMS by C=O on biochar also generated 1O2. Five byproducts were generated during degradation and eventually mineralized to CO2, H2O, NO3−, and F−. This study provides a facile strategy and new insights into the biochar-loaded zero-valent transition-metal-catalyzed PMS degradation of CECs
Thermal and Kinetic Analysis of the Process of Thermochemical Decomposition of Phosphogypsum with CO and Additives
Phosphogypsum (PG) is a waste byproduct from the processing
of phosphate rock by the ‘‘wet acid method’’
of fertilizer production. One of the main methods for reusing PG is
to decompose and recycle Ca and sulfur contained in it. However, the
decomposition reaction process is very complex because of its complicated
contents, and very high temperature is needed for the reaction. In
this paper, to decrease the reaction temperature, CO as a main reducer
and some additives were added in the decomposition process. Results
show that the decomposition temperature will decrease from 1000 to
809
°C with pure CO. When CaCl<sub>2</sub> is used as an additive,
the decomposition temperature can decrease to 790 °C, and at
the same time the reaction rate will be increased, the main product
being CaS at this condition. The thermal and kinetic action of this
process has also been discussed
Co-culture of macrophages and myofibroblasts induces α-SMA, TGF-β1 and Smad3 expression.
<p>(<b>A</b>) Representative immunohistochemical staining of α-SMA with 3-D co-culture in the present of Ang II. Scale bars: 50 µm. (<b>B</b>) Real-time PCR quantification of α-SMA and TGF-β1 mRNA expression. (<b>C</b>) Immunofluorescence staining of protein level of phosphorylated Smad3 (p-Smad3; green) and DDR2 (red) or Immunofluorescence staining of TGF-β1 (green) and DDR2 (red) in co-cultured WT macrophages and fibroblasts with neutralizing antibody to IL-6 and co-cultured IL-6-/- macrophages and fibroblasts with recombinant IL-6 (rIL-6) treatment. Scale bars: 50 µm. (n = 6 per group). (<b>D</b>) Western blot analysis and quantification of protein level of TGF-β1 and p-Smad3 in 3-D co-culture (n = 4 per group). *<i>P</i><0.05.</p
Generation of inflammatory factors and localization of IL-6 in macrophages or myofibroblasts in Ang II-infused mice.
<p>(<b>A</b>) RT-PCR analysis of mRNA expression of IL-6 in WT mice macrophages, cardiomyocytes and cardiac fibroblasts with Ang II treatment at 0,1,4,12 h respectively. *<i>P</i><0.05 vs. macrophages. (<b>B</b>) IL-6 (green) was detected in WT hearts and in myofibroblasts (red) in Ang II-treated hearts. Nuclei are DAPI stained (blue; right). (<b>C</b>) Macrophages (Mφ) were co-cultured with cardiac fibroblasts (CF), and the level of IL-6 production in the medium was measured by luminex assay (n = 5 per group). *<i>P</i><0.05; ND: no detective; **<i>P</i><0.01 vs. WT macrophages (Mφ(WT)) and cardiac fibroblasts(CF(WT)); **<i>P</i><0.01 vs. Mφ(WT)+cardiac fibroblasts CF(IL-6-/-) and Mφ(IL-6-/-)+CF(IL-6-/-).</p