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The development and design of fillers aid in improving the tribological performances of friction materials. Herein, the effects of the aspect ratio of mullite whisker on the tribological properties were studied. Mullite whiskers were prepared by the sol–gel process and the aspect ratio of the whisker was controlled by introducing aluminum fluoride (AlF3). The aspect ratio increased significantly at first and then decreased with increasing the contents of AlF3. The experimental results show that higher aspect ratio whiskers stabilized the friction coefficient while increased the wear rate. In addition, the composite with mullite whisker grown in excessive AlF3 (20%) resulted in a higher friction coefficient compared to adding inadequate AlF3 (10%). The Scanning Electron Microscope (SEM) and Energy Dispersive X‐Ray Spectroscopy (EDX) results indicated that higher aspect ratio of whisker was more likely to fall off from matrix which sequentially being compacted and formed contact plateaus during the friction process. In conclusion, it was found that abrasive wear and adhesive wear were the dominant wear mechanism. Highlights: The aspect ratio of mullite whisker was controlled within the range of 6 ~ 21.The tribological properties of whiskers reinforced composites were studied.The morphology of the mullite whisker affects the friction stability.The flaky mullite whisker can improve wear resistance of the composites. [ABSTRACT FROM AUTHOR]

Background: Clinically amyopathic dermatomyositis (CADM) is characterized by typical skin lesions with no (amyopathic) or subclinical (hypomyopathic) evidence of muscle involvement. Patients with CADM may also develop rapidly progressive interstitial lung disease (ILD), and have a poor prognosis. However, the diagnosis of rapidly progressive ILD faces a challenge during the severe acute respiratory syndrome coronavirus 2 pandemic. Severe acute respiratory syndrome and ground‐glass attenuation on a chest computed tomography scan are the presenting features in both conditions. Case presentation: A 45‐year‐old woman with amyopathic dermatomyositis had acute onset of fever and dyspnea in February 2020. She had abnormal lung findings on CT scan. Polymerase chain reaction testing for SARS‐CoV‐2 was not available at that time. Chest CT revealed non‐specific manifestations that could be either the signs of ILD or SARS‐CoV‐2 infection. Antiviral therapy was initiated with oseltamivir. Three days later, she had erythema on face, palm, and back. The ratio of lactate dehydrogenase (LDH) isoenzyme 3 to total LDH was elevated. The ratio of LDH isoenzyme 1 to total LDH was declined. Therefore, she was transferred to the rheumatology ward for further treatment. However, she died from respiratory failure 2 weeks later. Conclusions: We speculate that the altered LDH isoenzyme pattern may be an early biomarker for co‐occurrence of CADM and ILD. [ABSTRACT FROM AUTHOR]

Sunlight exposure and aging are two major factors in the deterioration of skin function. In the present study, we used eighty formalin-fixed human skin samples from sun-exposed and unexposed areas from old and young individuals to evaluate the presence of miR-125b-positive epidermal stem cells ( ESCs) by in situ hybridization. miR-125b-positive ESCs were detected in the basal layer of the epidermis. The density of miR-125b-positive ESCs was significantly associated with age rather than sun exposure, whereas the density of miR-125b-positive ESCs tended to decrease in the sun-exposed area. These data suggest the potential use of miR-125b as a surrogate marker for the quality of epidermal cells. [ABSTRACT FROM AUTHOR]

Due to the formerly widespread use of asbestos, malignant mesothelioma (MM) is increasingly frequent worldwide. MM is classified into epithelioid (EM), sarcomatoid (SM), and biphasic subtypes. SM is less common than EM but is recognized as the most aggressive type of MM, and these patients have a poor prognosis. To identify genes responsible for the aggressiveness of SM, we induced EM and SM in rats, using asbestos, and compared their transcriptomes. Based on the results, we focused on connective tissue growth factor (Ctgf), whose expression was significantly increased in SM compared with EM; EM itself exhibited an increased expression of Ctgf compared with normal mesothelium. Particularly in SM, Ctgf was a major regulator of MM proliferation and invasion through activation of the β-catenin-TCF-LEF signalling pathway, which is autocrine and formed a positive feedback loop via LRP6 as a receptor for secreted Ctgf. High Ctgf expression also played a role in the epithelial-mesenchymal transition in MM. Furthermore, Ctgf is a novel serum biomarker for both early diagnosis and determining the MM prognosis in rats. These data link Ctgf to SM through the LRP6-GSK3β-β-catenin-TCF-Ctgf autocrine axis and suggest Ctgf as a therapeutic target. [ABSTRACT FROM AUTHOR]

ABSTRACT Novel thermally and magnetically dual-responsive mesoporous silica nanoparticles [magnetic mesoporous silica nanospheres (M-MSNs)-poly( N-isopropyl acrylamide) (PNIPAAm)] were developed with magnetic iron oxide (Fe3O4) nanoparticles as the core, mesoporous silica nanoparticles as the sandwiched layer, and thermally responsive polymers (PNIPAAm) as the outer shell. M-MSN-PNIPAAm was initially used to control the release of sophoridine. The characteristics of M-MSN-PNIPAAm were investigated by transmission electron microscopy, Fourier transform infrared spectroscopy, X-ray diffraction, thermogravimetry, N2 adsorption-desorption isotherms, and vibrating specimen magnetometry analyses. The results indicate that the Fe3O4 nanoparticles were incorporated into the M-MSNs, and PNIPAAm was grafted onto the surface of the M-MSNs via precipitation polymerization. The obtained M-MSN-PNIPAAm possessed superparamagnetic characteristics with a high surface area (292.44 m2/g), large pore volume (0.246 mL/g), and large mesoporous pore size (2.18 nm). Sophoridine was used as a drug model to investigate the loading and release properties at different temperatures. The results demonstrate that the PNIPAAm layers on the surface of M-MSN-PNIPAAm effectively regulated the uptake and release of sophoridine. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40477. [ABSTRACT FROM AUTHOR]

A novel bi-template induced co-assembly method was employed to fabricate biomimetic bone substitute materials, collagen (COL)-fibroin/hydroxyapatite (COL-SF/HA) composite by using a combination of Type I COL and silk fibroin (SF) molecular templates. As a control, COL/HA and SF/HA composites were also synthesized via single-template assembly technology. The structure and morphology of the resulting assembly composites were investigated by X-ray diffractometer, Fourier transform infrared spectra, transmission electron microscope, and thermogravimetric analysis. Their sizes and size distributions were measured by DLS. The results indicated that the mineral phases in COL-SF/HA, COL-HA, and SF-HA composites were needle-like nano-HA crystals. In comparison to those in COL-HA and SF-HA, the mineral phase in COL-SF/HA displayed smaller size and more narrow distribution. Of all above biomimetic composites, the HA was well assembled with molecular template(s), and the organic content of the composite was about 12%-20%, which was quite similar to the natural bone in composition. CD and SDS-PAGE were used to examine the secondary structure and subunit composition of template proteins. The results revealed that the spatial structure of co-assembly template proteins played a pivotal role in controlling and regulating HA crystal nucleation and growth. Based on the experimental results above, a possible co-assembly mechanism for the HA growing on fibrous bi-template proteins was suggested. © 2009 Wiley Periodicals, Inc. J Biomed Mater Res Part A:, 2011. [ABSTRACT FROM AUTHOR]