High-Flow Nasal Oxygen versus Noninvasive Ventilation in Acute Exacerbation of Chronic Obstructive Pulmonary Disease Patients: A Meta-Analysis of Randomized Controlled Trials.

Background: High-flow nasal cannula (HFNC) can be used in stable chronic obstructive pulmonary disease (COPD) patients, but the effect of HFNC on clinical outcomes in patients with acute exacerbation of chronic obstructive pulmonary disease (AECOPD) is still uncertain. Methods: We searched electronic literature databases for randomized controlled trials (RCTs) comparing HFNC with noninvasive ventilation (NIV) in hypercapnic patients with AECOPD. The primary endpoint of this meta-analysis was PaCO2, PaO2, and SpO2. The secondary outcomes were the respiratory rate, mortality, complications, and intubation rate. Results: We included 7 RCTs with a total of 481 patients. There were no significant differences on measures of PaCO2 (MD = -0.42, 95%CI -3.60 to 2.75, Z = 0.26, and P = 0.79), PaO2 (MD = -1.36, 95%CI -4.69 to 1.97, Z = 0.80, and P = 0.42), and SpO2 (MD = -0.78, 95%CI -1.67 to 0.11, Z = 1.72, P = 0.08) between the HFNC group and the NIV group. There was no significant difference in measures of the mortality and intubation rate between the HFNC group (OR = 0.72, 95%CI 0.30 to 1.69, Z = 0.76, and P = 0.44) and the NIV group (OR = 2.38, 95%CI 0.49 to 11.50, Z = 1.08, and P = 0.28), respectively. But the respiratory rate in the HFNC group was lower than that in the NIV group (MD = -1.13, 95%CI -2.13 to -0.14, Z = 2.23, and P = 0.03), and fewer complications were found in the HFNC group (OR = 0.26, 95%CI 0.14 to 0.47, Z = 4.46, and P < 0.00001). Conclusion: NIV was noninferior to HFNC in decreasing PaCO2 and increasing PaO2 and SpO2. Similarly, the mortality and intubation rate was similar among the two groups. The respiratory rate and complications were inferior in the AECOPD group treated with HFNC.

Optimization of green infrastructure networks based on potential green roof integration in a high-density urban area-A case study of Beijing, China.

Green infrastructure network (GIN) optimization is an effective measure to reduce the landscape fragmentation caused by rapid urbanization. However, there are few targeted and practical studies of GINs in high-density urban areas with a prominent contradiction between ecological construction and land scarcity, leading to insufficient feasibility of most optimization paths as they avoid practical contradictions (scarcity of land, high cost, etc.). As an effective way to economically increase green infrastructure, green roofs have been demonstrated to provide habitats and stepping stones to increase landscape connectivity for high-mobility organisms. However, few studies have applied green roofs to GIN optimization. To address this question, a new approach to optimize GINs was proposed from the perspective of integrating potential green roofs (PGRs). A complete and feasible workflow was also established to rapidly, accurately, and cost-effectively extract PGRs, scientifically evaluate the comprehensive landscape connectivity accounting for PGR isolation factors, and practically optimize GINs according to the spatial differentiation of PGRs with high landscape connectivity. This was done by integrating high-spatial-resolution remote sensing, machine learning, morphological spatial pattern analysis, landscape index method, and a minimum cumulative resistance model. A case study in a typical high-density urban area within the Beijing Fifth Ring Road, China demonstrated the applicability and implications of the workflow. The results clearly showed that the study area had a high potential for green roof retrofitting, PGRs with high landscape connectivity could effectively improve the GINs, and the spatial differentiation characteristics of the PGR network optimization benefits provided the scientific guidance for developing targeted ecological strategies. The new approach effectively improves the scientificity and implementability of GINs. It also provides a strong reference for landscape planning and ecological construction in other high-density urban areas facing the contradiction between ecological construction and land scarcity.

Early Pulmonary Rehabilitation in Acute Exacerbation of Chronic Obstructive Pulmonary Disease: A Meta-Analysis of Randomized Controlled Trials.

Pulmonary rehabilitation (PR) is an essential method for Acute exacerbation in chronic obstructive pulmonary disease (AECOPD) recovery. We perform a meta-analysis to compare early PR with usual care. A literature search was performed through these databases: PubMed, MEDLINE database, Google Scholar, Cochrane, Embase from inception to July 2021. Eligible trials were clinical randomized controlled trials comparing the effects of early PR and usual care in AECOPD patients. The primary endpoint of this meta-analysis was FEV1% predicted, 6-min walk test (6MWD), modified Medical Research Council (mMRC) and George Respiratory Questionnaire-total (SGRQ-total). The secondary outcomes were borg dyspnea score, short-form 36 health survey questionnaire physical (SF-36 physical) and SF-36 mental. We included 13 RCTs with a total of 866 patients. There were no significant effects of the PR group on measures of FEV1% predicted (MD = 0.50, 95%CI -1.43 to 2.44, Z = 0.51, p = 0.61), borg dyspnea score (MD = -0.88, 95%CI -1.89 to 0.13, Z = 1.71, p = 0.09) and SF-36 mental (MD = 4.34, 95%CI -1.64 to 10.32, Z = 1.42, p = 0.16) compared with usual care. PR group achieved better 6MWD (MD = 97.58, 95%CI 17.21 to 177.96, Z = 2.38, p = 0.02), mMRC (MD = -0.36, 95%CI -0.52 to -0.21, Z = 4.56, p ˂ 0.00001), SGRQ-total (MD= -9.67, 95%CI -16.23 to -3.11, Z = 2.89, p = 0.004) and SF-36 physical (MD = 4.98, 95%CI 0.60 to 9.35, Z = 2.23, p = 0.03) compared with usual care group. Early PR in AECOPD patients would lead to better 6MWD, mMRC, SGRQ-total and SF-36 physical. But there were no significant effects of the PR group on measures of FEV1% predicted, borg dyspnea score and SF-36 mental.

Facile preparation of a novel modified biochar-based supramolecular self-assembled g-C3N4 for enhanced visible light photocatalytic degradation of phenanthrene.

The rational design of a novel and environmentally friendly photocatalytic composite for persistent pollutant removal, energy production and catalytic applications have attracted widespread interest. In this study, the new composite composed of KOH-modified biochar and g-C3N4 with different morphologies was successfully prepared with facile supramolecular self-assembly and thermal poly-condensation method. The characterization results of the as-prepared composites suggested that KOH-modified biochar had been well combined with g-C3N4 with different morphologies. These synthesized catalysts were used to degrade phenanthrene under visible light radiation. A-BC/g-C3N4-D performed best and removed 76.72% phenanthrene. Its first-order reaction rate constant was 0.355 h-1, which was 3.7 times higher than that of g-C3N4. A-BC/g-C3N4-D still exhibited a high photocatalytic activity after four cycles. Radical quenching results showed that superoxide radical (·O2-), hydroxyl radical (·OH) and hole (h+) could be used as active species in the redox reaction with phenanthrene. Based on the exploration results of gas chromatography-mass spectrometer (GC-MS), a possible reaction pathway of phenanthrene degradation was also proposed. This study provides a novel strategy for fabricating various high-performance photocatalysts and the removal of persistent organic pollutants.

Urban Metabolism of Food-Sourced Nitrogen among Different Income Households: A Case Study Based on Large Sample Survey in Xiamen City, China.

Food consumption is fundamental for urban households if they are to sustain production and daily life. Nitrogen resulting from food consumption has significantly contributed to pollutant emissions in urban ecosystems. Taking Xiamen city, a rapid urbanizing area of southeast China as a case study, we evaluated the food-sourced nitrogen consumption of households based on a large simple onsite questionnaire survey, as well as differences between households in the consumption of plant-based and animal-based foods. A material flow analysis (MFA) was conducted to simulate the urban metabolism of food-sourced nitrogen and environmental emissions among different income groups. The impacts of household attributes, plant-based food consumption, and animal-based food consumption on environmental nitrogen emissions were examined with a structural equation model (SEM). Our results show that the surveyed households' diets were more plant-based and less animal-based. Aquatic products and livestock were the source of 43.7% of food-sourced nitrogen, and 84.5% of the food-sourced nitrogen was discharge into the environment through direct discharge and waste treatment. Soil, water, and air emissions accounted for 62.8%, 30.1%, and 7.1% of the food-sourced nitrogen, respectively. Household income, household size, and household area are all associated with accelerating increases of nitrogen emissions released into the environment, though middle-income group households have the highest food-sourced environmental nitrogen emissions. On this basis, we discuss how to better manage the urban metabolism of food-sourced nitrogen, so as to improve urban household consumption, lower nitrogen emissions, and improve food security.

High-flow nasal cannula oxygen versus conventional oxygen for hypercapnic chronic obstructive pulmonary disease: A meta-analysis of randomized controlled trials.

INTRODUCTION: Low-concentration oxygen is an established way for the treatment of chronic obstructive pulmonary disease (COPD) with Type II respiratory failure. Hypercapnia can complicate both COPD exacerbations and stable COPD. Treating with noninvasive ventilation (NIV) can reduce carbon dioxide tension in arterial (PaCO2 ) in hypercapnic COPD. As an open system, high-flow nasal cannula oxygen (HFNC) is easy to tolerate and use. More researches are needed to focus on how HFNC is used to treat COPD patients with hypercapnic respiratory failure. METHODS: The Cochrane Library, Medline, EMBASE, and CINAHL database were retrieved from inception to October 2019. Eligible trials were clinical randomized controlled trials comparing the effects of HFNC and conventional oxygen on hypercapnic COPD patients. Two researchers assessed the quality of each study and extracted the data into RevMan 5.3 independently. The primary outcome was PaCO2 and the secondary outcome was PaO2 . RESULTS: Four RCTs with 329 patients were included. The research results indicated that PaCO2 in the HFNC group was similar to the conventional oxygen group. No significant difference were observed in PaCO2 (MD -0.98, CI: -2.67 to 0.71, Z = 1.14, p = 0.25) and PaO2 (MD -0.72, CI: -6.99 to 5.55, Z = 0.23, p = 0.82) between the HFNC group and conventional oxygen group. CONCLUSIONS: Our meta-analysis showed no difference in PO2 and PCO2 between the HFNC and conventional oxygen. But we should treat this conclusion with caution because the number of studies and participants is small and, there is heterogeneity in the PaO2 and PCO2 measurements between stable and AECOPD.

Synthesis of Biochar-Supported K-doped g-C3N4 Photocatalyst for Enhancing the Polycyclic Aromatic Hydrocarbon Degradation Activity.

The development of novel and green photocatalysts have attracted considerable attentions due to their excellent performance for environmental remediation, especially for the degradation of persistent pollutants. In this work, the biochar-supported K-doped g-C3N4 composites with the high photocatalytic activity under visible light irradiation was prepared by the calcination-impregnation method. The crystal structure, apparent morphology and functional group composition of the as-prepared photocatalytic materials were studied by X-ray diffraction (XRD), scanning electron microscopy (SEM) and Fourier transform infrared spectroscope (FTIR). Moreover, the characterization of UV-Vis diffuse reflectance spectra (UV-Vis DRS) and photoluminescence technique (PL) verified the good optical properties of resultant samples. Naphthalene was selected as the representative compound to evaluate the photocatalytic performance of the prepared photocatalysts under visible light irradiation. The evaluation results showed that the biochar-supported K-doped g-C3N4 composites exhibited excellent photocatalytic activity (82.19%). Moreover, the photocatalytic degradation rate basically remained unchanged after five cycles, indicating the good stability of the prepared photocatalysts. In addition, a possible mechanism for the photodegradation process was proposed on the basis of the main intermediates detected by gas chromatography-mass spectrometer (GC-MS). This study may provide a promising approach for the polycyclic aromatic hydrocarbon degradation by waste utilization of agricultural biomass and increasing the photocatalytic performance of pure g-C3N4.

Seasonal variation and ecological risk assessment of dissolved organic matter in a peri-urban critical zone observatory watershed.

Peri-urban ecosystems are among the most intensive areas in terms of competition between different ecosystem components. Dissolved organic matter (DOM) plays a significant role in aquatic carbon cycling. The chemical composition of DOM and associated potential ecological risks in peri-urban aquatic ecosystems are poorly understood. Herein, we used fluorescence excitation-emission matrix and parallel factor analysis (EEM-PARAFAC) to characterize DOM in a peri-urban critical zone observatory watershed in Eastern China. According to the theory of natural disaster risk formation, we calculated the ecological risk of DOM in the peri-urban watershed. Seasonal variation in DOM concentrations was observed, whereas fluorescent DOM concentrations were site-specific across four sub-watersheds. The analysis of DOM absorption properties revealed the presence of DOM components with high aromatic content and large molecular weight in the watershed. Four fluorescent components (two humic-like and two protein-like substances) were identified using the PARAFAC model. Spatial distribution analysis showed that DOM quality was mainly influenced by human activities, and the proportion of protein-like substance (C3) was strongly correlated with anthropogenic parameters. The distribution of optical indices indicated diverse sources of DOM in the watershed. Ecological risk related to DOM was greater in the dry season than the wet season. There was a slight risk in most areas, with an extreme risk in areas experiencing the most intensive human disturbance, which were also extremely or heavily vulnerable. The results emphasize the strong influence of human disturbance on the ecological risk of DOM in peri-urban aquatic ecosystems. Our study provides useful information for ecological risk assessment of DOM that is difficult to obtain using traditional chemical analysis.