The most common electron microscopic technique for obtaining information on size distributions of uncollapsed membrane vesicles is based on the method of van Venetie (1980). This technique involves the sizing of only those vesicles that were freeze fractured at their equatorial planes. As a result, only a small number of images can be used to generate size distributions. Further, the technique is susceptible to systematic error. An alternate approach is to consider the complete distribution of image sizes and use this distribution to determine the average size and distribution of the vesicles. It is shown that the mean vesicle size is 4/pi times the mean image size. As well, a parameter, m, which can be determined from the image distribution, can be used to characterize the vesicle distribution. The advantage of this new approach is that images of all vesicles are used, leading to a statistically better determination of vesicle sizes.
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http://dx.doi.org/10.1002/jemt.1060170409 | DOI Listing |
J Occup Environ Hyg
January 2025
Air Pollution Research Center, Iran University of Medical Sciences, Tehran, Iran.
The pathogenic potential of airborne particles carrying the SARS-CoV-2 viral genome was examined by considering the size distribution of airborne particles at given distances from the respiratory zone of an infected patient after coughing or sneezing with a focus on time, temperature, and relative humidity. The results show an association between the size distribution of airborne particles, particularly PM and PM, and the presence of viral genome in different stations affected by the distance from the respiratory zone and the passage of time. The correlation with time was strong with all the dependent factors except PM.
View Article and Find Full Text PDFPLoS One
January 2025
Faculty of Science and Engineering, Waseda University, Tokyo, Japan.
Gold (or electrum) in hydrothermal fluid precipitates directly from gold sulfide complex and/or partly via suspended nanoparticles. The hydrothermal fluid contains "invisible gold" that is atomically dispersed in sulfide minerals or as nanoparticles with a size of less than 10 nm. However, the contribution of these gold nanoparticles to the formation of native gold and its alloy with silver (electrum) remains unclear.
View Article and Find Full Text PDFPlant Physiol
January 2025
State Key Laboratory of Tree Genetics and Breeding, College of Biological Sciences and Technology, Beijing Forestry University, Beijing 100083, China.
In plants, cytoskeletal proteins assemble into dynamic polymers that play numerous roles in diverse fundamental cellular processes, including endocytosis, vesicle trafficking, and the spatial distribution of organelles and protein complexes. Plant elicitor peptides (Peps) are damage/danger-associated molecular patterns (DAMPs) that are perceived by the receptor-like kinases PEP RECEPTOR 1 (PEPR1) and PEPR2 to enhance innate immunity and inhibit root growth in Arabidopsis (Arabidopsis thaliana). To date, however, there is little evidence that the actin cytoskeleton of the host cell participates in DAMP-induced innate immunity.
View Article and Find Full Text PDFInsect Sci
January 2025
College of Life Sciences, Shandong Agricultural University, Tai'an, Shandong Province, China.
Wings are important organs of insects involved in flight, mating, and other behaviors, and are therefore prime targets for pest control. The formation of insect wings is a complex process that is regulated by multiple pathways. The Hedgehog (Hh) pathway regulates the distribution of wing veins, while the Hippo pathway modulates wing size.
View Article and Find Full Text PDFAm J Biol Anthropol
January 2025
School of Anthropology and Archaeology, The Australian National University, Canberra, Australian Capital Territory, Australia.
Introduction: Adverse experiences leading to physiological disruptions (stress) in early life produce cascade effects on various biological systems, including the endocrine and metabolic systems, which, in turn, shape the developing skeletal system. To evaluate the effects of stress on adipose and skeletal tissues, we examine the relationship between skeletal indicators of stress (porotic hyperostosis [PH] and cribra orbitalia [CO]), bone mineral density (BMD), vertebral neural canal (VNC) diameters, and adipose tissue distribution in a contemporary pediatric autopsy sample.
Methods: Data is from 702 (409 males, 293 females) individuals from a pediatric (0.
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