Publications by authors named "Ricardo Clark- Tapia"

Disholcaspis Dalla Torre & Kieffer, 1910 is reviewed for the first time in Mexico. A total of 23 species have been studied, 12 previously known species, 11 new species, and one new synonym: D. brasoae Cuesta-Porta, sp.

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Genetic studies in rare species are important to determine their patterns of genetic diversity among populations and implement conservation plans aimed to reduce extinction risks. is an endemic species with extremely small populations in central Mexico. This work analyzes the diversity and genetic structure of (Crassulaceae) to change the conservation status and propose conservation strategies.

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The dynamic microbiota of the human palmar surface (PS) is related to the various hygienic habits of humans and can be transmitted or exchanged upon contact with objects of daily use, such as the indispensable touchscreen cell phone (TCP); this interaction could allow the development of drug-resistant bacteria. The objective was to determine the drug-resistant bacterial contamination between PSs and TCPs in an urban community. Among the total bacterial colonies isolated and molecular and phylogenetically characterized based on the V4-V6 regions of the 16S rRNA gene from PSs and TCPs, the genera present in both types of samples were Staphylococcus (53.

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The present study measures the effect of citrate-coated magnetite nanoparticles (FeO-NPs) on the germination and early growth of Quercus macdougallii (oak). Two types of FeO-NPs were synthetized and characterized, being denominated NP1 and NP2. The synthesis was performed by the co-precipitation method and partial reduction of iron(II), respectively.

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Stenocereus eruca (Cactaceae), a prostrate cactus endemic to the Sonoran Desert, is thought to be highly clonal. We examined its clonal diversity and distribution: (1) at the population level, in four distinct populations along its distribution range; and (2) at a micro scale level, within a single population. Our objective was to evaluate the importance of sexual versus clonal recruitment through the use of RAPD markers.

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