Acute lung injury (ALI) is a common acute respiratory disease treated in the clinic. Intestinal microflora disorder affect lung diseases through the gut-lung axis. In this study, we explored the ...regulatory mechanism of the gut flora in the host defense against lipopolysaccharide (LPS)-induced ALI through the TLR4/NF-kB pathway by constructing a gut microflora dysbiosis-model with antibiotic administration and reconstruction of the intestinal microecology. Then, high-throughput sequencing was performed, and the levels of secreted IgA (sIgA), β-defensins, and Muc2 were measured to assess the gut flora and mucosal barrier. The expression of TLR4, NF-kB, TNF-α, IL-1β, oxidative stress and the lung wet/dry (W/D) ratio were evaluated to assess lung damage. Hematoxylin and eosin (HE) staining was performed to evaluate the damage to the gut and lung tissues. Accordingly, gut microbiota imbalance may regulate the TLR4/NF-kB signaling pathway in the lung immune system, activating oxidative stress in the lung and mediating lung injury through the regulation of the gut barrier. However, fecal microbiota transplantation (FMT) impairs the activity of the TLR4/NF-kB signaling pathway in the lung and decreases oxidative stress in animals with ALI by restoring the gut microecology.
Our results indicated the protective effect of gut flora in regulating immunity of LPS-induced ALI by modulating the TLR4/NF-kB signaling pathway which may induce inflammation and oxidative stress.
Accessing urban parks is important for promoting physical activities and improving public health. In this study, we propose the use of Google Maps crowdsourcing data and the incorporation of park ...attractiveness to model urban park accessibility in the complex urban environments of Hong Kong. The difference between using geometric and route distance, the effect of park attractiveness in measuring accessibility, and the benefits gained from using walk time compared to distance are investigated. Our result shows that (1) route and geometric distances have a strong correlation with a conversion factor of about 1.5; (2) the common assumption that park size can be a proxy for describing attractiveness may not be correct. Instead, park attractiveness should be explicitly considered for a more effective accessibility modeling; and (3) estimation by walking time shows that there are non-negligible impacts from street conditions and traffic on urban park accessibility. Moreover, district hotspots short of park accessibility or attractiveness can be explicitly detected. Overall, this developed approach provides a flexible and informative approach to model the accessibility to urban parks. The outputs will help city planners, health professionals, and policymakers to evaluate and improve urban park planning and equity in accessibility in high-density cities.
Beijing is among the first cities in China to implement a greenbelt policy to improve urban vegetation, which plays a crucial role in enhancing the urban ecological environment. The policies have ...shown remarkable results. However, long-term evaluation of the performance of the greenbelt policies in Beijing has not been carried out in order to quantitatively evaluate their effectiveness. In this study, long-term satellite observations of the normalized difference vegetation index (NDVI), land surface temperature, precipitation, and night-light from 2000 to 2020 are used to investigate the spatio-temporal variabilities in NDVI and explore the mechanisms of the impacts of the greenbelt policies in Beijing. The main results are as follows: (1) From 2000 to 2020, the overall NDVI in Beijing exhibited an upward trend, with the proportion of high-NDVI (>0.8) areas increasing from 26.18% in 2000 to 53.64% in 2020. The proportion of low-NDVI (<0.2) areas continued to decrease from 0.64% in 2000 to 0.2% in 2020. (2) The 1st Greenbelt Zone shows a significant increase in its NDVI (with an average increase of 0.296 units in the NDVI at district level), indicating that the policy’s implementation had a notable effect, while the 2nd Greenbelt Zone was mainly in a degraded state and a declining trend, indicating that its performance fell short of expectations. (3) During the preparation for the 2008 Summer Olympics, while the 1st Greenbelt Zone had a slightly negative effect on NDVI improvement, probably due to urban re-construction, the 2nd Greenbelt Zone showed a significant positive effect, leading to an increase of 0.013 units in the NDVI at district level. In addition, the correlation analysis shows that an increase in annual average land surface temperature leads to a decrease in the NDVI, while annual precipitation has a positive relationship with NDVI changes. This study highlights the importance of long-term satellite observations in evaluating the performance of greenbelt policies in Beijing. The evaluation approach developed in this study can be readily applied to similar cities globally.
Urban canyon classification plays an important role in analyzing the impact of urban canyon geometry on urban morphology and microclimates. Existing classification methods using aspect ratios require ...a large number of field surveys, which are often expensive and laborious. Moreover, it is difficult for these methods to handle the complex geometry of street canyons, which is often required by specific applications. To overcome these difficulties, we develop a street canyon classification approach using publicly available Google Street View (GSV) images. Our method is inspired by the latest advances in deep multitask learning based on densely connected convolutional networks (DenseNets) and tailored for multiple street canyon classification, i.e., H/W-based (Level 1), symmetry-based (Level 2), and complex-geometry-based (Level 3) classifications. We conducted a series of experiments to verify the proposed method. First, taking the Hong Kong area as an example, the method achieved an accuracy of 89.3%, 86.6%, and 86.1%, respectively for the three levels. Even using the field survey data as the ground truth, it gained approximately 80% for different levels. Then, we tested our pretrained model in five other cities and compared the results with traditional methods. The transferability and effectiveness of the scheme were demonstrated. Finally, to enrich the representation of more complicated street geometry, the approach can separately generate thematic maps of street canyons at multiple levels to better facilitate microclimatic studies in high-density built environments. The developed techniques for the classification and mapping of street canyons provide a cost-effective tool for studying the impact of complex and evolving urban canyon geometry on microclimate changes.
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•A multi-level classification hierarchy for urban canyon geometry based on Google Street View (GSV) images is proposed.•A multitask deep learning model is proposed to accurately classify urban canyons based on the classification hierarchy.•The urban canyons in Hong Kong are mapped and analyzed from multiple levels.
To survey the health-related quality of life (HRQoL) and its influencing factors among patients with COVID-19 in their first medical follow up.
All patients diagnosed with COVID-19 were discharged ...from 12 hospitals in Wenzhou, Zhejiang from Jan 17, 2020 to Mar 20, 2020. Prospectively collected and analyzed data included demographics, clinical symptoms, comorbidity, and chest CT imaging features at the first follow up, 1 month after discharge. All patients underwent the HRQoL evaluation with the Chinese version of Short-Form 36-item questionnaire (SF-36) as well as a general condition questionnaire. Factors associated with SF-36 were constructed using linear regression. Predictors of impaired physical component summary (PCS) and a mental component summary (MCS) were identified by logistic regression.
SF-36 demonstrated a significant difference in HRQoL in patients with COVID-19, except in physical function (PF), when compared to the general Chinese population (
<0.05). The multiple linear regressions demonstrated that age was negatively associated with PF, role physical (RP), but positively associated with vitality (VT) (
<0.05). PF, bodily pain (BP), and role-emotional (RE) were negatively associated with the female sex (
<0.05). For mental health, the clinical subtypes were significant associated factors (
< 0.05). Length of stay (LOS) was strongly negatively associated with RE and RP, and positively associated with VT (
< 0.05). Logistical regression revealed that non-obese overweight (OR 3.71) and obesity (OR 3.94) were risk factors for a low PCS and female sex (OR 2.22) was a risk factor for a low MCS.
Health-related quality of life was poor among COVID-19 patients at the 1 month follow-up. Patients suffered from significant physical and psychological impairment. Therefore, prospective monitoring of individuals exposed to SARS-CoV-2 is needed in order to fully understand the long-term impact of COVID-19, as well as to inform prompt and efficient interventions to alleviate suffering.
View factors for sky, trees, and buildings are three important parameters of the urban outdoor environment that describe the geometrical relationship between different surfaces from the perspective ...of radiative energy transfer. This study develops an approach for accurately estimating sky view factor (SVF), tree view factor (TVF), and building view factor (BVF) of street canyons in the high-density urban environment of Hong Kong using publicly available Google Street View (GSV) images and a deep-learning algorithm for extraction of street features (sky, trees, and buildings). As a result, SVF, TVF, and BVF maps of street canyons are generated. Verification using reference data of hemispheric photography from field surveys in compact high-rise and low-rise areas shows that the GSV-based VF estimates have a satisfying agreement with the reference data (all with R2 > 0.95), suggesting the effectiveness and high accuracy of the developed method. This is the first reported use of hemispheric photography for direct verification in a GSV-based streetscape study. Furthermore, a comparison between GSV-based and 3D-GIS-based SVFs shows that the two SVF estimates are significantly correlated (R2 = 0.40, p < 0.01) and show better agreement in high-density areas. However, the latter overestimates SVF by 0.11 on average, and the differences between them are significantly correlated with street trees (R2 = 0.53): the more street trees, the larger the difference. This suggests that a lack of street trees in a 3D-GIS model of street environments is the dominant factor contributing to the large discrepancies between the two datasets.
•GSV-based view factor estimation method with a deep-learning algorithm is proposed.•Sky, tree, and building view factors of street canyons are accurately quantified.•Hemispheric photography is used for direct verification of view factor estimates.•Comparison analysis of GSV-based and 3D-GIS-based methods is conducted.•The impacts of tree canopy and building density on SVF estimates are investigated.
The cobalt‐catalyzed alkoxylation of C(sp2)H bonds in aromatic and olefinic carboxamides has been developed. The reaction proceeded under mild conditions in the presence of Co(OAc)2⋅4H2O as the ...catalyst and tolerates a wide range of both alcohols and benzamide substrates, including even olefinic carboxamides. In addition, this reaction is the first example of the direct alkoxylation of alkenes through CH bond activation.
Alcohols in action: A wide range of alcohols and benzamide substrates functionalized with electron‐rich or electron‐poor substituents are tolerated in the title reaction. This practical reaction occurs under mild conditions.
This study presents a method for calculating solar irradiance of street canyons using Google Street View (GSV) images and investigates its spatiotemporal patterns in a high-density urban environment. ...In this method, GSV images provide a unique way to characterize the street morphology from which the diurnal solar path and solar radiation exposure can be estimated in a street canyon. Verifications of our developed method using free-horizon HKO observations and street-level field measurements show that both the calculated clear-sky and all-sky solar irradiance of street canyons well capture the diurnal and seasonal cycles. In the high-density urban areas of Hong Kong, we found that (1) the lowest monthly averaged solar irradiations in winter are 6.6 (December) and 4.6 (February) MJ/m2/day, and the highest values in summer are 17.3 (July) and 10.8 (June) MJ/m2/day for clear-sky and all-sky calculations, respectively; (2) The spatial variability of solar irradiation is closely related to sky view factor (SVF). In summer, the irradiation in a low-rise region (SVF≥0.7) on average is about three times that in a high-rise region (SVF≤0.3), and they differ by about five times in winter; (3) Street orientation has a significant impact on the solar radiation received in a high-density street canyon. In general, street canyons with West-East orientation receive higher solar irradiation during summer and lower during winter compared to those with South-North orientation. The generated maps of street-level solar irradiation may help researchers investigate the interactions between solar radiation, human health and urban thermal balance in high-density urban environments.
•A method to estimate street-level solar irradiance using Google Street View images is proposed.•Evaluation using free-horizon and street-level measurements is implemented.•Spatiotemporal patterns of street-level solar irradiation are accurately quantified.•Direct and diffuse components of solar irradiation are quantified separately.•Effect of street canyon geometries and morphologies on solar irradiation is analyzed.
Abstract The COVID-19 pandemic has altered the infection landscape for many pathogens. This retrospective study aimed to compare Haemophilus influenzae ( H. influenzae ) infections in pediatric CAP ...patients hospitalized before (2018–2019) and during (2020–2022) the COVID-19 pandemic. We analyzed the clinical epidemiology and antimicrobial resistance (AMR) patterns of H. influenzae from a tertiary hospital in southwest China. A total of 986 pediatric CAP patients with H. influenzae -associated infections were included. Compared to 2018, the positivity rate increased in 2019 but dropped significantly in 2020. Although it rose in the following 2 years, the rate in 2022 remained significantly lower than in 2019. Patients’ age during the pandemic was significantly higher than in 2018 and 2019, while gender composition remained similar across both periods. Notably, there were significant changes in co-infections with several respiratory pathogens during the pandemic. Resistance rates of H. influenzae isolates to antibiotics varied, with the highest resistance observed for ampicillin (85.9%) and the lowest for cefotaxime (0.0%). Resistance profiles to various antibiotics underwent dramatic changes during the COVID-19 pandemic. Resistance to amoxicillin-clavulanate, cefaclor, cefuroxime, trimethoprim-sulfamethoxazole, and the proportion of multi-drug resistant (MDR) isolates significantly decreased. Additionally, MDR isolates, alongside isolates resistant to specific drugs, were notably prevalent in ampicillin-resistant and β-lactamase-positive isolates. The number of pediatric CAP patients, H. influenzae infections, and isolates resistant to certain antibiotics exhibited seasonal patterns, peaking in the winter of 2018 and 2019. During the COVID-19 pandemic, sharp decreases were observed in February 2020, and there was no resurgence in December 2022. These findings indicate that the COVID-19 pandemic has significantly altered the infection spectrum of H. influenzae in pediatric CAP patients, as evidenced by shifts in positivity rate, demographic characteristics, respiratory co-infections, AMR patterns, and seasonal trends.
The manganese-catalyzed addition of C-2 position of indoles to maleimides has been achieved under additive-free conditions. The manganese catalyst exhibits excellent chemo- and regioselectivity, good ...functional group compatibility, and high catalytic efficiency. The substrate scope can also be extended to maleates, ethyl acrylate, 1,4-dihydro-1,4-epoxynaphthalene, pyrroles, and 2-phenylpyridine, which further demonstrates the universality of this straightforward approach.
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