An innovative microcrystalline cellulose(MCC)natural fibre powder-reinforced PLA biocomposite was investigated using the hand lay-up technique.The polymer matrix composite(PMC)samples were prepared by varying the weig...An innovative microcrystalline cellulose(MCC)natural fibre powder-reinforced PLA biocomposite was investigated using the hand lay-up technique.The polymer matrix composite(PMC)samples were prepared by varying the weight percentages(wt.%)of both PLA matrix and MCC reinforcement:pure PLA/100:0,90:10,80:20,70:30,60:40 and 50:50 wt.%,respectively.From the results obtained,MCC powder,with its impressive aspect ratio,proved to be an ideal reinforcement for the PLA,exhibiting exceptional mechanical properties.It was evident that the 80:20 wt.%biocomposite sample exhibited the maximum improvement in the tensile,flexural,notched impact,compressive strength and hardness by 28.85%,20.00%,91.66%,21.53%and 35.82%,respectively compared to the pure PLA sample.Similarly,during the thermogravimetric analysis(TGA),the same 80:20 wt.%biocomposite sample showed a minimum weight loss of 20%at 400℃,among others.The morphological study using Field Emission Scanning Electron Microscopy(FE-SEM)revealed that the uniform distribution of cellulose reinforcement in the PLA matrix actively improved the mechanical properties of the biocomposites,especially the optimal 80:20 wt.%sample.Importantly,it was evident that the optimal PLA/cellulose biocomposite sample could be a suitable and alternative sustainable,environmentally friendly and biodegradable material for semi/structural applications,replacing synthetic and traditional components.展开更多
Here, we report a case of a young man who presented with a significant upper gastrointestinal bleed treated by endoscopic removal of multiple hyperplastic polyps. Gastric hyperplastic polyps are a relatively uncommon ...Here, we report a case of a young man who presented with a significant upper gastrointestinal bleed treated by endoscopic removal of multiple hyperplastic polyps. Gastric hyperplastic polyps are a relatively uncommon cause of overt gastrointestinal bleeding. While most hyperplastic gastric polyps are asymptomatic, they may present with abdominal pain, iron def iciency anemia or gastric outlet obstruction. These polyps are associated with conditions such as Helicobacter pylori gastritis and atrophic autoimmune gastritis, which predispose the epithelium to chronic inf lammation and epithelial repair.The patient presented to Northwestern Memorial Hospital in July 2011. The polyps were resected by clip-assisted snare polypectomy. Histopathologic assessment of the resected polyps demonstrated multiple, nonulcerative hyperplastic polyps measuring 1.3-1.8 cm in size, without evidence of dysplasia or malignancy. This case describes a young adult patient with multiple, large gastric polyps causing overt gastrointestinal bleeding. This is a rare presentation in a young individual, as these polyps are typically identifi ed in patients older than 60 years of age and less commonly, pediatric populations.展开更多
基金funding from Researchers Supporting Project Number(RSP2024R355),King Saud University,Riyadh,Saudi Arabia.
文摘An innovative microcrystalline cellulose(MCC)natural fibre powder-reinforced PLA biocomposite was investigated using the hand lay-up technique.The polymer matrix composite(PMC)samples were prepared by varying the weight percentages(wt.%)of both PLA matrix and MCC reinforcement:pure PLA/100:0,90:10,80:20,70:30,60:40 and 50:50 wt.%,respectively.From the results obtained,MCC powder,with its impressive aspect ratio,proved to be an ideal reinforcement for the PLA,exhibiting exceptional mechanical properties.It was evident that the 80:20 wt.%biocomposite sample exhibited the maximum improvement in the tensile,flexural,notched impact,compressive strength and hardness by 28.85%,20.00%,91.66%,21.53%and 35.82%,respectively compared to the pure PLA sample.Similarly,during the thermogravimetric analysis(TGA),the same 80:20 wt.%biocomposite sample showed a minimum weight loss of 20%at 400℃,among others.The morphological study using Field Emission Scanning Electron Microscopy(FE-SEM)revealed that the uniform distribution of cellulose reinforcement in the PLA matrix actively improved the mechanical properties of the biocomposites,especially the optimal 80:20 wt.%sample.Importantly,it was evident that the optimal PLA/cellulose biocomposite sample could be a suitable and alternative sustainable,environmentally friendly and biodegradable material for semi/structural applications,replacing synthetic and traditional components.
文摘Here, we report a case of a young man who presented with a significant upper gastrointestinal bleed treated by endoscopic removal of multiple hyperplastic polyps. Gastric hyperplastic polyps are a relatively uncommon cause of overt gastrointestinal bleeding. While most hyperplastic gastric polyps are asymptomatic, they may present with abdominal pain, iron def iciency anemia or gastric outlet obstruction. These polyps are associated with conditions such as Helicobacter pylori gastritis and atrophic autoimmune gastritis, which predispose the epithelium to chronic inf lammation and epithelial repair.The patient presented to Northwestern Memorial Hospital in July 2011. The polyps were resected by clip-assisted snare polypectomy. Histopathologic assessment of the resected polyps demonstrated multiple, nonulcerative hyperplastic polyps measuring 1.3-1.8 cm in size, without evidence of dysplasia or malignancy. This case describes a young adult patient with multiple, large gastric polyps causing overt gastrointestinal bleeding. This is a rare presentation in a young individual, as these polyps are typically identifi ed in patients older than 60 years of age and less commonly, pediatric populations.
