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1.
Sci Total Environ ; 917: 170371, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38280582

RESUMO

Excavated waste is a byproduct of microbial decomposition and fermentation following landfill disposal. The effective management and utilization of excavated waste offer broad prospects for environmental and resource protection, as well as economic growth. While current research predominantly focuses on plastics in landfills, the physico-chemical properties of excavated waste over extended landfilling time remain unclear. This study aimed to address this gap by excavating waste from a landfill in Tianjin, China, with a maximum landfilling time of 18 years. The findings revealed that, compared to municipal solid waste (MSW), the excavated waste exhibited increased calorific value, ash content, and fixed carbon content after screening the landfill-mined-soil-like-fine fraction. The average calorific value of the excavated waste could reach 57.8 MJ/kg. Additionally, the oxygen content in the excavated combustible waste exceeded that of MSW, increasing from 25.59 % to 34.22 %. This phenomenon is potentially linked to the oxidation of attached soil impurities and waste. The study identified polyethylene (PE), polypropylene (PP), expanded polystyrene (EPS), polyethylene terephthalate (PET), and wood as the primary combustible components. Notably, the excavated waste exhibited a significant decrease in surface gloss, adopting a rough texture with apparent holes, potentially attributed to the acidification and corrosion of organic matter during fermentation. Nevertheless, the breaking of molecular bonds could also contribute to waste fragmentation. Furthermore, an increase in landfilling time resulted in a more pronounced decrease in mechanical properties. For instance, the failure load of PE decreased from 15.61 N to 6.46 N, and PET reduced from 884.83 N to 186.56 N. The chemical composition of excavated waste has changed, with -OH and CO observed in PE with an 18-year landfilling time. In conclusion, these results provide a theoretical foundation for the recycling of excavated waste and contribute to the advancement of waste management and recycling technologies.

2.
Chemosphere ; 350: 141104, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38171400

RESUMO

The loss of active components, weak acid resistance, and low recover efficiency of common Ca-based catalysts limited its further development and application. In this study, to effectively produce biodiesel from waste cooking oil (WCO), a green and recyclable magnetic acid-base bifunctional CoFe/biochar/CaO catalyst was prepared from sargassum and river snail shell waste via hydrothermal method. The catalysts' structure and properties were investigated by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), CO2/NH3 temperature programmed desorption (CO2/NH3 TPD), etc., The prepared catalyst mainly consisted of the carbon skeleton, CoFe alloy, and CaO. CoFe alloy provided catalyst's ferromagnetism for magnetic separation as well as acid sites for transesterification of WCO. Ca and other metal species with nanoscale (∼5.64 nm) were dispersively anchored on sargassum biochar surface, thereby leading to good catalytic activity (99.21% biodiesel yield) and stability (91.70% biodiesel yield after the 5th cycle). In addition, response surface methodology-Box-Behnken design (RSM-BBD) revealed the optimal operational conditions were 16:1 methanol/oil molar ratio, 3 wt% catalyst dosage, 73 °C for 157 min. The maximum biodiesel yield predicted value was 98.29% and the experimental value was 99.21%, indicating good satisfaction of the established model. Moreover, the quality of WCO biodiesel met the ASTM D6751 standards. This study benefits magnetic waste-derived acid-base bifunctional catalysts for the disposal of WCO towards sustainable biodiesel production.


Assuntos
Biocombustíveis , Carvão Vegetal , Óleos de Plantas , Óleos de Plantas/química , Biocombustíveis/análise , Dióxido de Carbono , Esterificação , Culinária , Catálise , Ligas , Fenômenos Magnéticos
3.
Front Surg ; 10: 1107613, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37066008

RESUMO

Objectives: In this systemic review and network meta-analysis, we investigated pancreaticoduodenectomy (PD), pylorus-preserving pancreaticoduodenectomy (PPPD), and different modifications of duodenum-preserving pancreatic head resection (DPPHR) to evaluate the efficacy of different surgical procedures. Methods: A systemic search of six databases was conducted to identify studies comparing PD, PPPD, and DPPHR for treating pancreatic head benign and low-grade malignant lesions. Meta-analyses and network meta-analyses were performed to compare different surgical procedures. Results: A total of 44 studies were enrolled in the final synthesis. Three categories of a total of 29 indexes were investigated. The DPPHR group had better working ability, physical status, less loss of body weight, and less postoperative discomfort than the Whipple group, while both groups had no differences in quality of life (QoL), pain scale scores, and other 11 indexes. Network meta-analysis of a single procedure found that DPPHR had a larger probability of best performance in seven of eight analyzed indexes than PD or PPPD. Conclusion: DPPHR and PD/PPPD have equal effects on improving QoL and pain relief, while PD/PPPD has more severe symptoms and more complications after surgery. PD, PPPD, and DPPHR procedures exhibit different strengths in treating pancreatic head benign and low-grade malignant lesions. Systematic Review Registration: https://www.crd.york.ac.uk/prospero/, identifier: CRD42022342427.

4.
J Coll Physicians Surg Pak ; 33(3): 249-253, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36945151

RESUMO

OBJECTIVE: To explore the predictive value of gastric antral cross-sectional area (CSA) in the occurrence of postoperative nausea and vomiting (PONV) by analysing the association between gastric antral CSA measured by ultrasound and frequency of PONV after laparoscopic cholecystectomy. STUDY DESIGN: Observational study. Place and Duration of the Study: Department of Anaesthesiology, The First Hospital of Wannan Medical College, Yijishan Hospital of Wannan Medical College, from October 2021 to February 2022. METHODOLOGY: Gastric antral ultrasound (US) was performed in 266 patients undergoing laparoscopic cholecystectomy (LC) before anaesthesia induction, after it, and after surgery. The data obtained were used to evaluate the relationship between gastric antral CSA and PONV. RESULTS: The gastric antral CSA in Semi-recumbent decubitus (SRD) position >398.85 mm2 (AUC=0.623) highly indicated the occurrence of PONV. In addition, the subject performance characteristic curve of a binary logistics retrospective model for predicting PONV (AUC=0.805) highly indicated the occurrence of PONV. CONCLUSION: Gastric US assessment of gastric antral CSA might change the current assessment model of PONV risk. This study showed that the gastric antral CSA in the SRD position after anaesthesia induction and a binary logistics retrospective model could be used to predict the occurrence of PONV, which could be helpful to adjust intraoperative and postoperative interventions and accelerate the recovery of patients. KEY WORDS: Postoperative nausea and vomiting, Gastric ultrasound, Gastric cross-sectional area, Perioperative period.


Assuntos
Colecistectomia Laparoscópica , Náusea e Vômito Pós-Operatórios , Humanos , Náusea e Vômito Pós-Operatórios/epidemiologia , Colecistectomia Laparoscópica/efeitos adversos , Estudos Retrospectivos , Estômago
5.
BMC Complement Altern Med ; 16: 25, 2016 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-26801102

RESUMO

BACKGROUND: Polygonum hydropiper L. is widely used as a traditional remedy for the treatment of dysentery, gastroenteritis. It has been used to relieve swelling and pain, dispel wind and remove dampness, eliminate abundant phlegm and inflammatory for a long time. Previous study showed that antioxidants especially flavonoids pretreatment alleviated sepsis-induced injury in vitro and in vivo. In the present study, the possible anti-inflammatory effect of flavonoids from normal butanol fraction of Polygonum hydropiper L. extract (FNP) against inflammation induced by lipopolysaccharide (LPS) was evaluated in vivo and in vitro. METHODS: The content of total flavonoid of FNP was determined by the aluminum colorimetric method. The content of rutin, quercetin and quercitrin was determined by HPLC method. Mice received FNP orally 3 days before an intra-peritoneal (i.p.) injection of lipopolysaccharide (LPS). Total superoxidase dismutase (T-SOD), total antioxidant capacity (T-AOC), glutathione peroxidase (GSH-PX), glutathione (GSH), myeloperoxidase (MPO) and malondialdehyde (MDA) levels were measured. Tumor necrosis factor-α levels in serum and tissue was measured. mRNA expressions of pro-inflammatory cytokines in lung were assessed by Real-Time PCR. Histopathological changes were evaluated in lung, ileum and colon. We also investigated FNP on reactive oxygen species (ROS), nitric oxide (NO) and pro-inflammatory cytokines (TNF-α, IL-1ß, IL-6 and IL-8) production, inducible nitric oxide synthase (iNOS), Cyclooxygenase-2 (COX-2) protein expression, phosphorylation of MAPKs and AMPK in LPS-stimulated RAW264.7 cells. RESULTS: FNP increased the levels of T-SOD, T-AOC, GSH-PX and GSH, decreased the levels of TNF-α, MPO and MDA, attenuate the histopathological lesion in LPS-stimulated mice. FNP inhibited production of inflammatory cytokines, ROS and NO, protein expressions of iNOS and COX-2, phosphorylation of ERK, JNK and c-JUN in MAPKs, promoted phosphorylation of AMPKα suppressed by LPS. CONCLUSION: These results suggested in vivo anti-inflammatory activities of FNP might contributed to its enhancement in antioxidant capacity, its inhibitory effects may be mediated by inhibiting the phosphorylation of JNK, ERK and c-JUN in MAPKs signaling pathways.


Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Flavonoides/farmacologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Extratos Vegetais/farmacologia , Polygonum/química , Animais , Linhagem Celular , Mediadores da Inflamação/metabolismo , Lipopolissacarídeos , Macrófagos , Masculino , Camundongos , Fosforilação
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