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Incineration ash stabilization in the pavement is an effective approach to reduce environmental impact and proper disposal. This study aimed to achieve a bibliometric analysis of "ash stabilization in pavement" research during 2002-2021, considering language, chronological trends, source types, subject areas, document types, affiliations, journals, countries, and author keywords. Also, social network analysis (SNA) was used for trends mapping and global collaboration determination among countries. The results exposed that the number of publications has been significantly increased by more than 14-fold over the studied period. Engineering (42%), material science (17%), and environmental science (10%) were three major subject areas. The USA, by 383 publications, was the leading country, followed by India (370) and China (288). The most independent rate of the publications belonged to India (93%), while Australia ranked 1st in cooperator publications (63.4%). The "Construction and Building Materials" published the most related articles, followed by "Journal of Materials in Civil Engineering" and "Road Materials and Pavement Design." Among the top ten productive institutes and organizations, four affiliations were from China, and three institutes were from the USA. Edil, T.B. (34) from the USA, Arulrajah, A. (29) from Australia, and Horpibulsuk, S. (24) from Thailand were the most productive authors. "Fly ash," "compressive strength," "durability," "geopolymer," "strength," and "resilient modulus" had the most growth rate in recent years, based on the author keywords analysis. Besides, the increase of emerging keywords, "pervious concrete," "reclaimed asphalt pavement," and "lateritic soil" are noteworthy in the second half period.

Introduction: Development of right ventricular dysfunction (RVD) is associated with adverse clinical outcome in patients doing coronary artery by-pass grafting (CABG). Right ventricular-pulmonary artery (RV-PA) coupling which describes the relationship between the RV systolic function and its afterload has been recently introduced as a prognostic parameter in multiple patient groups. In this study we evaluated the prognostic role of TAPSE/PASP ratio as a surrogate for RV-PA coupling in patients undergoing CABG. Methods: RV-PA coupling was assessed using the TASPE/PASP ratio. Echocardiography was done within 48 hours pre-operative and within 72 hours post-operative. The primary endpoint included postoperative RVD and rehospitalization within 3 months. Results: Among 100 patient doing CABG, the mean age was 59 years with predominant male gender. About 2 thirds of the patients were hypertensive and more than half of them were diabetic. The mean left ventricular ejection fraction was 62% and mean RV fractional area change (FAC) was 50% with mean TAPSE 19 mm and mean TAPSE/PASP of 0.62. Post-operative RVD developed in 35% of the patients and re-hospitalization for cardiac reasons occurred in 11%. The independent predictors of development of post-operative RVD were lower TAPSE/PASP ratio, presence of diabetes mellitus and higher levels of total Cholesterol (P-value: 0.03, 0.0001, 0.0001 respectively). The independent predictors of re-hospitalization were higher triglyceride levels and lower TAPSE/PASP Ratio (P-value: 0.02 and 0.002 respectively). Conclusion: TAPSE/PASP ratio as a surrogate for RV-PA coupling is a non-invasive simple bedside tool that can be used to predict adverse clinical outcomes in patients undergoing coronary artery by-pass grafting.

Obesity is an independent risk factor for cardiovascular diseases. Coronary artery calcium (CAC) is a direct measure of coronary atherosclerosis. The study investigated the effect of bariatric surgery on CAC scores in people with severe obesity subjected to laparoscopic sleeve gastrectomy (LSG). This prospective study included 129 people with severe obesity in two groups; the LSG group (n=74) subjected to surgery and the diet group (n=55), managed by a diet regimen and lifestyle modification. Cardiovascular risk was assessed by Framingham risk score (FRS) and coronary calcium score (CCS) measured by computed tomography initially and after 3 years. The two groups had a comparable CAD risk before treatment according to FRS or CCS. After treatment, CCS improved significantly in the LSG group (p=0.008) but not in the diet group (p=0.149). There was no correlation between FRS and CCS (r=0.005, p=0.952). Treatment resulted in significant weight reduction and improved fasting blood glucose and lipid profile in the two groups. The change of weight, blood glucose, and HDL, and remission of diabetes mellitus (DM) were significantly higher in the LSG group compared to the diet group. LSG may reduce the risk of developing future cardiovascular comorbidities evidenced by reducing CAC scores. Significant weight reduction and improvement of cardiovascular risk factors may recommend LSG as a cardioprotective procedure in people with severe obesity.

Purpose Epicardial fat thickness is an interesting parameter of early atherosclerosis. We prospectively assessed whether weight loss following laparoscopic sleeve gastrectomy (LSG) leads to a significant reduction in the epicardial fat thickness (EFT) and the correlation between the decline in the epicardial fat thickness with other clinical parameters. Methods A prospective analysis of 98 cases that were scheduled to undergo LSG and followed up for 12 months was conducted. EFT was assessed using two-dimensional (2 D) echocardiography. Results A total of 98 cases and 70 controls were enrolled. EFT demonstrated a significant reduction at follow-up in the whole group (median 8.9 (1.95) versus 7.65 (1.67) mm, respectively). The degree of reduction was higher in the LSG cohort compared to control cohort 1.3 (0.4) versus 1 (0.4), respectively; p

Despite the increasing amount of waste being reused, recycled, or energetically valorized, landfills continue to play an important role in waste management strategies. Many researchers have studied various aspects of landfilling, regarding positive or negative features. However, a few of them have summarized the related literature, resulted in a lack of overall progress understanding. This paper aimed to perform a bibliometric analysis of landfilling research during 2000–2017. Various aspects, such as document types, languages, major journals, key countries, authors, and keywords were all systematically analyzed. The collaborations among authors and countries were wholly constructed, visualized, and evaluated through the application of social network analysis based on co-authorship relations. Moreover, to discover the most leading topics on landfill discussion, keyword clustering analysis was conducted using co-occurrences relations. The research showed that the number of landfill-related publications has significantly increased within the period. Regarding both quality and quantity, the United States was the most leading country. As well, Rowe, R.K., from Canada, was quantitatively the most productive author. The findings of this study indicated that landfill leachate was the most studied topic in the literature. Besides, the keywords “global warming” and “sustainability” had the highest rate of growth during the studied period. This paper also demonstrated that the most productive countries in landfill research have had a significant contribution to decrease the total amount of landfilling using other waste disposal alternatives (such as incineration with/without energy recovery) or waste management strategies.

Carbon fibre-reinforced polymer (CFRP) was introduced over three decades ago to the field of structural engineering. The goal of this study is to investigate the effects of different types of sands...

Biofuel production from sugarcane has been researched in terms of the environment. Performing a bibliometric method and visual network analysis, the purpose of this study is to assess the trends in sugarcane and bioethanol researches and recognize the associated hotspots based on 4958 publications from 1991 to 2020. The geographical distribution of articles and per capita sugarcane production in the world were also examined. As a widely used database in the field of bibliometric, the Scopus database was used in this research to collect relevant literature. The research method includes the bibliometric analysis of documents and citations, subject categories, journals, countries, institutions, authors, geographical distribution status of articles and annual sugarcane production, top articles. Finally, the social network of the author's keywords was reviewed. The VOSviewer software was used for performing graphic maps showing the co-authorship and communication of countries, authors and keywords. The results show a high growth in the number of published documents in this field and the tendency change from agricultural sciences to environmental sciences in documents and journals. Based on the study's gained results, Brazil is the undisputed leader, publishing 43.8% of the documents in last three decades, followed by the USA and India.

Soil–geosynthetic interaction is a key factor for designing and analyzing reinforced soil structures. In this investigation, the effect of different moisture content on the behavior of soil–geogrid interfaces is evaluated using direct shear and pullout tests. The results are presented and discussed in terms of direct shear and interface shear behavior, the frictional resistance of interfaces, efficiency factor, pullout resistance, pullout behavior, and apparent friction coefficient. The results revealed that a decrease in moisture content resulted in an increase in the both interface friction angle and adhesion of specimens. Moreover, the interface friction angle of sand–geogrid specimens in pullout tests was higher than that of direct shear tests. According to interface shear results, the efficiency factors ranged from 0.87 to 0.99. Based on pullout results, the apparent friction coefficient was found to be in the range of 0.77–1.72.

Waste foundry sand (WFS) is the by-product of the foundry industry, which is produced about 0.6 tons per 1 ton of foundry industry production. While it cannot be recycled or reused, it will be disposed of in landfills. Today, with increasing attention to environmental issues, the reuse and recycle of materials because of limited resources have been considered. Due to the desirable properties of WFS, many studies have been done on the properties and performance of its use in various industries, especially in concrete technology. The purpose of this paper is to conduct a bibliometric analysis of foundry sand research during the years 1971-2020. Various aspects, such as document types, languages, major journals, key countries, authors, and keywords, have been examined. The collaborations among authors and countries were constructed, visualized, and evaluated through the application of the social network analysis method based on co-authorship relations. Also, keyword cluster analysis has been performed using co-occurrence relations to discover the most prominent issues related to WFS. The results showed that the number of publications (TP) has improved significantly in recent years, especially in 2018-2020. It has increased from 1 in 1971 to 38 in 2020. The engineering subdivision with 33% has had the highest number of papers. Also, India, China, and the USA have the highest number of publications, respectively. Statistical data from the author keyword study showed that in general, papers can be classified into three categories in terms of subject: first, characteristics of WFS and its importance; second, the use of WFS in concrete and the study of mechanical and physical properties as one of its applications; and the third, investigation on environmental effects and damage caused by disposal and landfill of WFS and efforts to find solutions for recycling and reuse. The keywords "Waste Foundry Sand," "Foundry Sand," and "Compressive Strength" with a growth rate of 2700%, 1900%, and 1100%, respectively, are important topics in the field of WFS research.

Landfilling brings many difficulties such as leaching of hazardous substances, methane gas production, loss of land, and natural resources such as groundwater, soil, and minerals. Enhanced landfill mining (ELFM) gives an opportunity to deal with such related problems. This study aimed to assess the environmental performance of ELFM through the application of life cycle assessment (LCA). SimaPro (v 8.5) was utilized to model the consequential life cycle assessment. Moreover, a comprehensive cost-benefit analysis was applied to assess the economic performance along with the Monte Carlo simulation to address the related uncertainties. In addition, the indicator of net present value (NPV) was adopted to understand the economic feasibility of the project. The case study landfill was the closed 55-hectare dumpsite of the municipality of Tehran in Kahrizak due to the need for further landfilling space in the future. The results of this study indicated that ELFM could lead to remarkable environmental benefits compared with the landfill’s current status (the do-nothing scenario). The ELFM project reduced the impact of global warming by 1,759,790 ton CO2 eq, equaling to 134% reduction in comparison with the do-nothing scenario. Moreover, the potential profitability of the project was calculated to be 370 million $. Among the processes, recycling and thermal treatment of waste significantly dominated the environmental results of the project. Although the research was based on a case study landfill, the methodology can be applied to similar projects worldwide.

Aims Worsening of renal function (WRF) is a common complication in patients with acute decompensated heart failure (ADHF). We aimed to evaluate the role of intrarenal Doppler ultrasound (IRD) in the early prediction of WRF in this patient group. Methods and results Among 90 patients (age: 57.5 ± 11.1 years; 62% male) hospitalized with ADHF, resistivity index (RI), acceleration time (AT), and pulsatility index (PI) were measured on admission and at 24 and 72 h. WRF was defined as increased serum creatinine ≥0.3 mg/dL from baseline. Adverse clinical outcomes were defined as the composite of death, use of vasopressors, and need for ultrafiltration for refractory oedema. WRF developed in 40% of patients. Mean values of renal AT, RI, and PI on admission were 59.7 ± 15, 0.717 ± 0.08, and 1.5 ± 0.48 ms, respectively. At 24 h, there was significant decrease in AT (to 56.7 ± 10 ms, P = 0.02) and renal RI (to 0.732 ± 0.07; P

Soil-reinforcement interface friction is an important geotechnical engineering parameter that needs to be assessed in achieving a safe and cost-effective design. In this study, the effect of mean particle size (D50), type, and surface properties of reinforcements on shear behavior of soil-reinforcement interface were evaluated using direct shear test. Three types of sands with different D50 and similar properties, and six types of reinforcing materials with different surface features; three conventional types (GTX, GGB, and GC) and three novel types (CFRP, SPSCFRP, and GeoFRP), were used for this purpose. The direct shear test (DST) device was modified and proposed to determine the shear strength and friction angle between soil and reinforcements at different normal stresses. Test results revealed that interface shear strength between soil and reinforcements depends on both particle size of the sand and type of reinforcement. The influence of particle size was more significant when coarser size was used since the interlocking behavior occurred between the sand particles and the asperities of reinforcing material. However, the surface roughness of reinforcement affected the shear strength to an extent.