An approach for factoring the effects of a planetary thermal history into a predicted set of crater statistics for an icy satellite is developed and forms the basis for subsequent data inversion studies. The key parameter is a thermal evolution-dependent critical time for which craters of a particular size forming earlier do not contribute to present-day statistics. An example is given for the satellite Ganymede and the effect of the thermal history is easily seen in the resulting predicted crater statistics. A preliminary comparison with the data, subject to the uncertainties in ice rheology and impact flux history, suggests a surface age of 3.8 x 10(9) years and a radionuclide abundance of 0.3 times the chondritic value.
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http://dx.doi.org/10.1126/science.210.4466.185 | DOI Listing |
Comp Biochem Physiol Part D Genomics Proteomics
January 2025
Herpetological Research Center, College of Life Sciences, Nanjing Normal University, Nanjing 210023, Jiangsu, China. Electronic address:
Temperature is closely linked to the life history of organisms, and thus thermoception is an important sensory mechanism. Transient receptor potential (TRP) ion channels are the key mediators of thermal sensation. In this study, we analyzed the sequence characteristics of TRPs in gecko Hemiphyllodactylus yunnanensis and compared the phylogenetic relationships of TRP family members among different Squamata species.
View Article and Find Full Text PDFWarming associated with climate change is driving poleward shifts in the marine habitat of anadromous Pacific salmon ( spp.). Yet the spawning locations for salmon to establish self-sustaining populations and the consequences for the ecosystem if they should do so are unclear.
View Article and Find Full Text PDFEcol Evol
January 2025
Minderoo Foundation Perth Western Australia Australia.
Coral reefs worldwide are threatened by increasing ocean temperatures because of the sensitivity of the coral-algal symbiosis to thermal stress. Reef-building corals form symbiotic relationships with dinoflagellates (family Symbiodiniaceae), including those species which acquire their initial symbiont complement predominately from their parents. Changes in the composition of symbiont communities, through the mechanisms of symbiont shuffling or switching, can modulate the host's thermal limits.
View Article and Find Full Text PDFPolymers (Basel)
December 2024
Key Laboratory of Archaeomaterials and Conservation, Ministry of Education, Institute of Cultural Heritage and History of Science & Technology, University of Science and Technology Beijing, Beijing 100083, China.
Palm Leaf Manuscripts represent a significant component of the world's cultural heritage. Investigating their primary chemical components and understanding the transformations these materials undergo under environmental influences are crucial for elucidating their material characteristics and aging mechanisms and developing effective strategies for preventive conservation. This study utilized infrared absorption spectroscopy and X-ray diffraction analysis to examine changes in the primary chemical components of Palm Leaf Manuscripts under varying relative humidity conditions over extended periods.
View Article and Find Full Text PDFJ Cancer Res Ther
December 2024
Department of Ultrasound, The Third Affliated Hospital of Sun Yat-sen University, Guangzhou City, Guangdong Province, China.
Purpose: To evaluate the risk factors that may delay enhanced recovery in the ablation of liver tumors.
Methods: A total of 310 patients who underwent ultrasound-guided ablation of liver tumors under general anesthesia were prospectively enrolled. Baseline data, intraoperative parameters, and postoperative events were evaluated.
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