Current evidence suggests that the size of the capillary-to-fiber (C/F) interface is a major determinant of O2 flux into muscle fibers, and methods have been developed for estimating the size of this region via the C/F perimeter ratio in perfusion-fixed material (Mathieu-Costello O, Ellis CG, Potter RF, MacDonald IC, and Groom AC. Am J Physiol Heart Circ Physiol 261: H1617-H1625, 1991) and the quotient of the individual, fiber-based C/F number ratio and fiber perimeter (C/F perimeter exchange index) in muscle biopsies (Hepple RT. Can J Appl Physiol 22: 11-22, 1997). The purpose of this study was to compare the two methods and examine how differences in muscle tissue preparation between perfusion fixation and frozen biopsy can influence the estimate of the size of the C/F interface. The left medial gastrocnemius muscle of nine purpose-bred dogs was perfusion fixed in situ, and a sample from the midportion of the midbelly was processed for microscopy. A corresponding sample from the right gastrocnemius muscle obtained by open biopsy in six of the nine animals was frozen for histochemistry. A significant correlation was found between the two estimates of the size of the C/F interface in the same sections of perfusion-fixed material (r = 0.75, P < 0.05). However, estimates of the size of the C/F interface were smaller in biopsies than perfusion-fixed material, and there was no significant relationship between the estimates in the two preparations. This was due to differences in fiber size (33% larger fiber cross-sectional area in biopsy material after normalization for sarcomere length; P < 0.05) and muscle sampling between the two tissue preparations.
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http://dx.doi.org/10.1152/jappl.2001.91.5.2150 | DOI Listing |
ACS Appl Mater Interfaces
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State Key Laboratory of Polymer Materials Engineering, College of Polymer Science and Engineering, Sichuan University, Chengdu, Sichuan 610065, P.R. China.
Silicone rubber (SR) holds significant potential for everyday wearable devices due to its inherent sweat resistance and flexibility. However, its broader applicability is constrained by poor oil resistance and a suboptimal slip performance. In this study, we developed an SR with durable oil resistance and enhanced slip properties by forming a covalently bonded barrier layer on its surface through a one-step in situ fluorination reaction using F/N.
View Article and Find Full Text PDFJ Am Chem Soc
January 2025
School of Chemistry and Chemical Engineering, Key Laboratory of Colloid and Interface Chemistry of the Ministry of Education, Shandong University, Jinan 250100, P. R. China.
Herein, we describe a hexavalent tellurium-based chalcogen bonding catalysis platform capable of addressing reactivity and selectivity issues. This research demonstrates that hexavalent tellurium salts can serve as a class of highly active chalcogen bonding catalysts for the first time. The tellurium centers in these hexavalent catalysts have only one exposed interaction site, thus providing a favorable condition for the controlling of reaction selectivity.
View Article and Find Full Text PDFJ Hazard Mater
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School of Environmental Science and Engineering, Shanghai Jiao Tong University, 200240, China.
With the upgrading and obsoleting of electric refrigeration equipment, significant amounts of waste hydrochlorofluorocarbon (HCFCs) refrigerants are being generated, bringing serious ozone-depleting and global warming effects. HCFCs, containing chlorine and fluorine, have the potential to be converted into acids by mineralization. Hydrothermal technology possesses a tightly sealed environment and high thermal efficiency, providing significant advantages in treating volatile HCFCs.
View Article and Find Full Text PDFNat Commun
December 2024
Guangdong Research Institute of Water Resources and Hydropower, Guangzhou, 510630, China.
J Colloid Interface Sci
March 2025
State Key Laboratory of Heavy Oil Processing, School of Chemical Engineering, China University of Petroleum (East China), Qingdao 266580, China. Electronic address:
Proton exchange membrane fuel cells (PEMFCs) are recognized as promising next-generation energy sources for automotive applications. The development of efficient, durable, and low-cost electrocatalysts to enhance the oxygen reduction reaction (ORR) kinetics is crucial. Herein, we report the synthesis of Pt@C/F-COOH catalysts via the pyrolysis and HNO oxidation of the carbon support, followed by the growth of Pt nanoparticles through reduction.
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