5 research outputs found
A Study on Processing Defects and Parameter Optimization in Abrasive Suspension Jet Cutting of Carbon-Fiber-Reinforced Plastics
Abrasive suspension jet (ASJ), an accurate cold-cutting technology, can address traditional processing issues relating to carbon-fiber-reinforced plastics (CFRPs) like tool wear, interlayer delamination, large heat-affected zone, and low surface roughness. This study employed the use of an ASJ to cut CFRPs and an ultra-depth optical microscope to scan the cut surface to analyze interlayer delamination, surface roughness, kerf taper, and shoulder damage. Regression analysis was conducted to establish a prediction model for cutting quality based on surface roughness, kerf taper, and shoulder damage. Various types of CFRP cutting quality were analyzed using jet parameters. It was found that the use of ASJ to process CFRP results in the following defects: The range of surface roughness variation is from 0.112 Ī¼m to 0.144 Ī¼m. Surface roughness is most influenced by stand-off distance, followed by traverse speed and jet pressure. The range of kerf taper variation is from 4.737Ā° to 10.1Ā°. Kerf taper is most influenced by stand-off distance, followed by jet pressure and traverse speed. The range of shoulder damage variation is from 3.384 Ī¼m2 to 10 Ī¼m2. Shoulder damage is most influenced by jet pressure, followed by traverse speed and stand-off distance. A prediction model for cutting quality was developed based on surface roughness, kerf taper, and shoulder damage, providing data support for ASJ cutting of CFRPs. The optimal parameter combination is a stand-off distance of 1 mm, a jet pressure of 30 MPa, and a traverse speed of 30 mm/min
Hybrid MesoporousāMicroporous Nanocarriers for Overcoming Multidrug Resistance by Sequential Drug Delivery
Combination
chemotherapy with a modulator and a chemotherapeutic
drug has become one of the most promising strategies for the treatment
of multidrug resistance (MDR) in cancer therapy. However, the development
of nanocarriers with a high payload and sequential release of therapeutic
agents poses a significant challenge. In this work, we report a type
of hybrid nanocarriers prepared by polydopamine (PDA) mediated integration
of the mesoporous MSN core and the microporous zeolite imidazolate
frameworks-8 (ZIF-8) shell. The nanocarriers exploit storage capacities
for drugs based on the high porosity and molecular sieving capabilities
of ZIF-8 for sequential drug release. Particularly, large amounts
of an anticancer drug (DOX, 607 Ī¼g mg<sup>ā1</sup>) and
a MDR inhibitor curcumin (CUR, 778 Ī¼g mg<sup>ā1</sup>) were sequentially loaded in the mesoporous core via ĻāĻ
stacking interactions mediated by PDA and in the microporous shell
via the encapsulation during ZIF-8 growth. The sustained release of
DOX was observed to follow earlier and faster release of CUR by acid-sensitive
dissolution of the ZIF-8 shell. Furthermore, the nanoparticles showed
good biocompatibility and effective cellular uptake in in vitro evaluations
using drug-resistant MCF-7/ADR cancer cells. More importantly, the
preferentially released CUR inhibited the drug efflux function of
the membrane P-glycoprotein (P-gp), which subsequently facilitated
the nuclear transportation of DOX released from the PDA-MSN core,
and, in turn, the synergistic effects on killing MDR cancer cells.
The hybrid mesoporousāmicroporous nanocarrier holds great promise
for combination chemotherapy applications on the basis of sequential
drug release
Dissecting the effect of ileal faecal diversion on the intestine using singleācell sequencing
Abstract Background Although ileal faecal diversion is commonly used in clinical settings, complications accompany it. Elucidating the intestinal changes caused by ileal faecal diversion will help resolve postoperative complications and elucidate the pathogenic mechanisms of associated intestinal disorders, such as Crohn's disease (CD). Therefore, our study aimed to provide new insights into the effects of ileal faecal diversion on the intestine and the potential mechanisms. Methods Singleācell RNA sequencing was performed on proximal functional and paired distal defunctioned intestinal mucosae from three patients with ileal faecal diversion. We also performed in vitro cellular and animal experiments, tissue staining and analysed public datasets to validate our findings. Results We found that the epithelium in the defunctioned intestine tended to be immature, with defective mechanical and mucous barriers. However, the innate immune barrier in the defunctioned intestine was enhanced. Focusing on the changes in goblet cells, we demonstrated that mechanical stimulation promotes the differentiation and maturation of goblet cells through the TRPA1āERK pathway, indicating that the absence of mechanical stimulation may be the main cause of defects in the goblet cells of the defunctioned intestine. Furthermore, we found obvious fibrosis with a proāfibrotic microenvironment in the defunctioned intestine and identified that monocytes may be important targets for faecal diversion to alleviate CD. Conclusions This study revealed the different transcription landscapes of various cell subsets and the potential underlying mechanisms within the defunctioned intestine, when compared to the functional intestine, based on the background of ileal faecal diversion. These findings provide novel insights for understanding the physiological and pathological roles of the faecal stream in the intestine