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This paper investigates the unclear influence mechanism of the surfactant effect on improving coal seam wettability and CO2-enhanced coalbed methane technology to enhance the gas extraction efficiency in some coal mines under highly mineralized environments in China. Specifically, the microinfluence mechanism of the coupling effect of nonionic surfactant OP-10 and highly mineralized coal samples under special treatment on the wettability of coal seam is examined. By measuring the contact angle and surface tension of the samples, it is confirmed that high mineralization can limit the effect of surfactants on improving the wettability of coal seams to a certain point. Infrared spectroscopy and X-ray diffraction measurements were conducted on the samples under coupling conditions. It is found that high mineralization impedes the effectiveness of surfactants in enhancing the wettability of coal seams. The surfactants interact with coal samples at the functional group level, producing new hydrophilic functional groups and increasing the content of kaolin with strong hydrophilic properties, thereby increasing the wettability of coal seams. However, these hydrophilic functional groups disappear under coupling conditions and hydrophobic functional groups are produced. Additionally, high mineralization inhibits the effect of surfactants on the phase composition of coal samples. The findings of this research provide a theoretical basis for water injection of highly mineralized coal seams and methane replacement recovery by carbon dioxide technology, promoting the practical application of water injection and gas injection displacement of coal seams.
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The low efficiency of the closed-loop supply chain in construction and demolition waste (CDW) recycling has restricted the green development of China's construction industry. Additionally, the government's reward-penalty mechanism has a huge influence on green development. This study aimed to investigate the effect of green development performance (GDP) and the government's reward-penalty mechanism on the decision-making process of production and recycling units, as well as to reveal the optimal strategies under different conditions. Therefore, the strategies' evolutionary paths of production and recycling units were investigated by using evolutionary game theory. Firstly, an evolutionary game model between production units and recycling units was proposed under the government's reward-penalty mechanism. Then, the evolutionary stability strategies in different scenarios were discussed. Finally, the effects of the relevant parameters on the evolutionary paths of the game model were analyzed using numerical simulations. The main conclusions are as follows. (1) When the range of GDP changes, the evolutionary stable strategy changes accordingly. GDP plays a positive role in promoting the high-quality development of the CDW recycling supply chain, but an increase in GDP can easily lead to the simultaneous motivation of free-riding. (2) The government's reward-penalty mechanism effectively regulates the decision-making process of production and recycling units. An increase in the subsidy rate and supervision probability helps to reduce free-riding behavior. Moreover, the incentive effect of the subsidy probability on recycling units is more obvious, while the effect of the supervision probability on improving the motivation of active participation for production units is more remarkable. This paper not only provides a decision-making basis to ensure production and recycling units to make optimal strategy choices under different conditions but also provides a reference for the government to formulate a reasonable reward-penalty mechanism that is conducive to a macro-control market.
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Industria de la Construcción , Teoría del Juego , Administración de Residuos , China , Materiales de Construcción , Gobierno , Humanos , Reciclaje , Recompensa , Desarrollo SostenibleRESUMEN
The extensive waste produced in construction and demolition activities affects the ecological environment, impeding green development in countries worldwide, including China. China has paid increasing attention to managing construction and demolition waste (CDW). However, most of the existing research only qualitatively studies the factors affecting the recycling of CDW and does not reveal the critical factors. Therefore, based on stakeholder theory and the grey-DEMATEL method, this paper aims to identify and quantitatively analyze the critical factors in CDW recycling from the perspective of China. This paper drew the following conclusions: (1) Stakeholders in China's CDW recycling mainly include the government, CDW production units, and CDW recycling units. (2) Public policy, government subsidies, media promotion, human resources, cost, environmental awareness, technological innovation, and supply chain management are the eight dimensions with 13 factors that constitute CDW recycling in China. (3) For the total relations between factors affecting the recycling of CDW in China, the most influential factor is specific legislation and regulations. The factor with the highest degree of prominence is environmental awareness. The factor with the largest net cause value is the rationality of disposal and landfill charges. The factor with the largest net effect value is experienced construction workers. (4) The critical factors in China's CDW recycling include specific legislation and regulations, mandatory degree of normative standards, environmental awareness, the supply of raw materials for CDW recycling units, and the sale of remanufactured products. Finally, this paper identifies the following management implications: (1) the government should prioritize the task of improving specific legislation and regulations, with a focus on a mandatory degree of normative standards. (2) CDW production units should put the task of improving environmental awareness high on their agenda, with a focus on the supply of raw materials for recycling units. (3) CDW recycling units should prioritize the issue of the sale of remanufactured products. This paper also provides a theoretical basis for revealing the critical factors of CDW recycling in other countries or regions.
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Industria de la Construcción , Materiales de Construcción/análisis , Reciclaje/métodos , Administración de Residuos , China , Industria de la Construcción/economía , Materiales de Construcción/economía , Humanos , Residuos Industriales , Administración de Residuos/métodosRESUMEN
Anemia is one of the major complications in predialysis patients with chronic kidney disease (CKD). A clearer cognition of the prognostic impact of hemoglobin (Hb) or hematocrit (Hct) target on the outcomes of predialysis patients with CKD is significant. This article aims to establish the suitable hemoglobin target to provide clinical guidance. MEDLINE, EmBase, the Cochrane Library and other databases were searched with both MeSH terms and keywords to gather researches that assessed all-cause mortality, stroke, treatment of renal replacement, and transfusion. The meta-analysis was accomplished via Revman 5.3 version. Totally, 13 eligible studies involving 7606 patients were included. There was a significantly lower risk of transfusion (risk ratio (RR) 0.59, 95% CI 0.52 to 0.67; p<0.00001) in the higher hemoglobin group than in the lower one. However, no significant difference was found in all-cause mortality (RR 1.10, 95% CI 0.98 to 1.23; p=0.11), stroke (RR 1.32, 95% CI 0.82 to 2.10; p=0.25) and treatment of renal replacement including hemodialysis, peritoneal dialysis and renal transplant (RR 1.08, 95% CI 0.95 to 1.22; p= 0.23) between the higher hemoglobin group and the lower one. The results favor the higher hemoglobin target. To target the higher hemoglobin when treating predialysis patients with CKD may decrease the risk of transfusion without increasing the risk of death, stoke, and treatment of renal replacement.
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Anemia/terapia , Terapia Molecular Dirigida , Ensayos Clínicos Controlados Aleatorios como Asunto , Diálisis Renal , Insuficiencia Renal Crónica/terapia , Anciano , Anemia/mortalidad , Transfusión Sanguínea , Femenino , Hemoglobinas/metabolismo , Humanos , Masculino , Persona de Mediana Edad , Sesgo de Publicación , Insuficiencia Renal Crónica/mortalidad , Accidente Cerebrovascular/complicacionesRESUMEN
BACKGROUND: Anemia is extremely common among dialysis patients and underlies some of the symptoms associated with reduced kidney function, including fatigue, depression, reduced exercise tolerance, and dyspnea. OBJECTIVES: A clearer cognition of the prognosistic impact of hemoglobin (Hb) or hematocrit (Hct) target for the outcomes of dialysis patients is urgent. This article aims to establish the suitable hemoglobin in order to provide clinical guidance. METHODS: MEDLINE, EmBase, the Cochrane Library and other databases were searched with both MeSH terms and keywords to gather randomized controlled trials that assessed all-cause mortality, cardiovascular events, fistula thrombosis, infectious diseases and transfusion among dialysis-dependent patients using erythropoiesis-stimulating agents. The meta-analysis was accomplished via Revman 5.3 version. FINDINGS: Totally, nine eligible studies were included, with study subjects involving 3228 patients. There was a significantly higher risk of fistula thrombosis without heterogeneity (RR 1.34, 95% CI 1.15-1.55; p < 0.05) in the higher Hb target group than in the lower Hb target group in the fixed effects model. However, no significant difference was found in all-cause mortality in the fixed effects model (RR 1.09, 95% CI 0.93-1.27; p = 0.30), cardiovascular events (RR 0.77, 95% CI 0.31-1.92; p = 0.58), infectious diseases (RR 0.69, 95% CI 0.24-1.96; p = 0.49) and transfusion (RR 0.92, 95% CI 0.42-1.99; p = 0.82) in the random effects model between the higher Hb target group and the lower Hb target group. DISCUSSION: The results favor lower Hb target. To target lower Hb target when treating dialysis patients with anemia may decrease the risk of fistula thrombosis without increasing the risk of death, cardiovascular events, infectious diseases and transfusion.
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Anemia/tratamiento farmacológico , Hematínicos/normas , Hemoglobinas/análisis , Diálisis Renal/efectos adversos , Insuficiencia Renal Crónica/terapia , Anemia/sangre , Anemia/mortalidad , Hematínicos/uso terapéutico , Hematócrito , Hemoglobinas/normas , Humanos , Guías de Práctica Clínica como Asunto , Ensayos Clínicos Controlados Aleatorios como Asunto , Insuficiencia Renal Crónica/sangre , Insuficiencia Renal Crónica/complicaciones , Insuficiencia Renal Crónica/mortalidad , Resultado del TratamientoRESUMEN
BACKGROUND: Serum biomarkers, such as serum creatinine (SCr) and serum cystatin C (SCysC), have been widely used to evaluate renal function in patients who have chronic kidney disease (CKD). OBJECTIVE: This article aims to assess the value of determining SCr and SCysC levels in patients that have long-term kidney disease. Approaches: MEDLINE, EmBase, the Cochrane Library and other databases were searched using both MeSH terms and text words to collect research that assessed the diagnostic value of using SCr and SCysC to evaluate Glomerular Filtration Rate (GFR) in patients with CKD. Data were converted into fourfold tables. Summary Receiver Operating Characteristic Curves and meta-analyses were accomplished via Meta-Disc version 1.4. RESULTS: In total, 21 relevant articles involving 3112 study subjects were included in our review. Results showed that the collective sensitivity for SCr and SCysC was 0.77 (95% CI: 0.69-0.84) and 0.87 (95% CI: 0.82-0.91), respectively. The pooled specificity for SCr and SCysC was 0.91 (95% CI: 0.86-0.94) and 0.87 (95% CI: 0.82-0.91), respectively. Subgroup analyses demonstrated that when GFR cut-off values are set to 60 (ml/min/1.73 m2), the pooled sensitivity is 0.94 (95% CI: 0.90-0.96) for SCysC and 0.75 (95% CI: 0.68-0.82) for SCr. CONCLUSIONS: The diagnostical accuracy for impaired kidney function favors SCysC. Confidence intervals for the pooled sensitivity and specificity for SCr and SCysC overlap. However, SCysC is more sensitive for estimating GFR than SCr when GFR cut-off values are set to 60 (ml/min/1.73 m2).