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Quantitative imaging of the sub-organ distributions of nanomaterials in biological tissues via laser ablation inductively coupled plasma mass spectrometry
Quantitative imaging of nanomaterials in sub-organ regions using gelatin-based standards.
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- Award ID(s):
- 2108044
- PAR ID:
- 10534609
- Publisher / Repository:
- Royal Society of Chemistry
- Date Published:
- Journal Name:
- The Analyst
- Volume:
- 148
- Issue:
- 18
- ISSN:
- 0003-2654
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Since the first phylogenetic study of the order Batrachospermales,Batrachospermumwas shown to be paraphyletic. Subsequently, sections of the genus have been methodically investigated usingDNAsequences and morphology in order to propose new genera and delineate species.BatrachospermumsectionTurfosais the last section with multiple species yet to be examined. New sequence data of specimens from Europe and the United States were combined with the sparse sequence data already available. Phylogenetic analyses usingrbcL andCOI‐5P sequences showed this section to be a well‐supported clade, distinct fromBatrachospermumsectionBatrachospermumand its segregate genera. Section Turfosais raised to the generic rank asPaludicolagen. nov. Substantial genetic variation within the genus was discovered and 12 species are recognized based onDNAsequence data as well as morphological characters and geographic distribution. The following morphological characters were applied to distinguish species: branching pattern (pseudodichotomous or irregular), whorl size (reduced or well developed), primary fascicles (curved or straight), spermatangia origin (primary or secondary fascicles), and carposporophyte arrangement (loose or dense). Previously published species were transferred to the new genus:P. turfosa,P. keratophyta,P. orthosticha,P. phangiae,andP. periploca. Seven new species are proposed as follows:P. groenbladiifrom Europe;P. communis,P. johnhallii, andP. leafensisfrom North America; andP. aquanigra,P. diamantinensis, andP. turfosiformisfrom Brazil. In addition, three unsequenced species in the section,P. bakarensis,P. gombakensis, andP. tapirensis, were transferred to the new genus.more » « less
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Context.In recent years, theR-Process Alliance (RPA) has conducted a successful search for stars that are enhanced in elements produced by the rapid neutron-capture (r-)process. In particular, the RPA has uncovered a number of stars that are strongly enriched in lightr-process elements, such as Sr, Y, and Zr. These so-called limited-rstars were investigated to explore the astrophysical production site(s) of these elements. Aims.We investigate the possible formation sites for light neutron-capture elements by deriving detailed abundances for neutron-capture elements from high-resolution spectra with a high signal-to-noise ratio of three limited-rstars. Methods.We conducted a kinematic analysis and a 1D local thermodynamic equilibrium spectroscopic abundance analysis of three stars. Furthermore, we calculated the lanthanide mass fraction (XLa) of our stars and of limited-rstars from the literature. Results.We found that the abundance pattern of neutron-capture elements of limited-rstars behaves differently depending on their [Ba/Eu] ratios, and we suggest that this should be taken into account in future investigations of their abundances. Furthermore, we found that theXLaof limited-rstars is lower than that of the kilonova AT2017gfo. The latter seems to be in the transition zone between limited-rXLaand that ofr-I andr-II stars. Finally, we found that unliker-I andr-II stars, the current sample of limited-rstars is largely born in the Galaxy and is not accreted.more » « less
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Abstract ObjectivesCortical bone geometry is commonly used to investigate biomechanical properties of primate mandibles. However, the ontogeny of these properties is less understood. Here we investigate changes in cortical bone cross‐sectional properties throughout capuchin ontogeny and compare captive versus wild, semi‐provisioned groups. Tufted capuchins (Sapajusspp.) are known to consume relatively hard/tough foods, while untufted capuchins (Cebusspp.) exploit less mechanically challenging foods. Previous research indicates dietary differences are present early in development and adultSapajusmandibles can resist higher bending/shear/torsional loads. Materials and methodsThis study utilized microCT scans of 22Cebusand 45Sapajusfrom early infancy to adulthood from three sample populations: one captiveCebus, one captiveSapajus, and one semi‐provisioned, free‐rangingSapajus. Mandibular cross‐sectional properties were calculated at the symphysis, P3, and M1. If the tooth had not erupted, its position within the crypt was used. A series of one‐way ANOVAs were performed to assess differences between and within the sample populations. ResultsMandible robusticity increases across ontogeny for all three sample populations.Sapajuswere better able to withstand bending and torsional loading even early in ontogeny, but no difference in shear resistance was found. Semi‐provisioned, free‐rangingSapajustend to show increased abilities to resist bending and torsional loading but not shear loading compared to captiveSapajus. DiscussionThis study helps advance our understanding of the primate masticatory system development and opens the door for further studies into adaptive plasticity in shaping the masticatory apparatus of capuchins and differences in captive versus free‐ranging sample populations.more » « less
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1039/D3AN00839H
