Publications by authors named "Paul Marsh"

Article Synopsis
  • - Electrodeposited amorphous hydrated iridium oxide (IrOx) is effective for pH sensing due to its sensitivity and fabrication ease, but issues like durability and performance variability exist, which can be managed through potentiostatic conditioning (PC)
  • - The study utilized techniques such as voltammetry and various forms of spectroscopy to analyze IrOx after PC, revealing that the process can significantly control sensor performance, reducing sensitivity and offset values
  • - Findings indicate that during PC, there's a transformation in the chemical states of IrOx, shifting from hydroxide to oxide forms, and this change is linked to improved calibration and performance stability over approximately two months
View Article and Find Full Text PDF

Bioelution tests measure in vitro the release of metal ion in surrogate physiological conditions (termed "bioaccessibility") and estimate the potential bioavailability relative to that of a known reference metal substance. Bioaccessibility of cobalt ion from twelve cobalt substances was tested in three artificial lung fluids (interstitial, alveolar and lysosomal) to gather information about the substances' fate and potential bioavailability in the respiratory tract after inhalation. The results can be used as one line of evidence to support grouping and read-across for substances lacking in vivo data, and where in vivo testing is not readily justifiable.

View Article and Find Full Text PDF

GABA (Gamma-aminobutyric acid) is the main inhibitory neurotransmitter in the central nervous system of mammals. It is known to be related with various neurological disorders. GABA plays a crucial role in normal neuronal activity, information processing and plasticity, and neuronal network synchronization.

View Article and Find Full Text PDF

A chip-based electrochemical biosensor is developed herein for the detection of organophosphate (OP) in food materials. The principle of the sensing platform is based on the inhibition of dimethoate (DMT), a typical OP that specifically inhibits acetylcholinesterase (AChE) activity. Carbon nanotube-modified gold electrodes functionalized with polydiallyldimethylammonium chloride (PDDA) and oxidized nanocellulose (NC) were investigated for the sensing of OP, yielding high sensitivity.

View Article and Find Full Text PDF

The purpose of this review is to assess the state-of-the-art fabrication methods, advances in genome editing, and the use of machine learning to shape the prospective growth in cardiac tissue engineering. Those interdisciplinary emerging innovations would move forward basic research in this field and their clinical applications. The long-entrenched challenges in this field could be addressed by novel 3-dimensional (3D) scaffold substrates for cardiomyocyte (CM) growth and maturation.

View Article and Find Full Text PDF
Article Synopsis
  • The survival of razorback sucker fish, which are endangered, relies on management strategies that protect them from predation by non-native fish during breeding.
  • In Lake Mohave, this involves capturing and rearing larvae in safe environments before releasing them back into the lake as larger fish that can avoid being eaten.
  • Research shows that these management efforts have successfully maintained the razorback sucker’s genetic diversity, but the small overall population size increases their risk of extinction, indicating a need for measures to boost their numbers.
View Article and Find Full Text PDF

Ten microsatellite loci were characterized for 34 locations from roundtail chub (Gila robusta complex) to better resolve patterns of genetic variation among local populations in the lower Colorado River basin. This group has had a complex taxonomic history and previous molecular analyses failed to identify species diagnostic molecular markers. Our results supported previous molecular studies based on allozymes and DNA sequences, which found that most genetic variance was explained by differences among local populations.

View Article and Find Full Text PDF

The first species of Caenophanes Foerster recorded from America north of Mexico is described: Caenophanes harlowi Haimowitz and Marsh, and a key to distinguish the two described New World species is provided. We discuss evidence that suggests that Caenophanes is likely to have cosmopolitan distribution and may be more common than might be anticipated from the current number of described species.

View Article and Find Full Text PDF

Time-series analysis is used widely in ecology to study complex phenomena and may have considerable potential to clarify relationships of genetic and demographic processes in natural and exploited populations. We explored the utility of this approach to evaluate population responses to management in razorback sucker, a long-lived and fecund, but declining freshwater fish species. A core population in Lake Mohave (Arizona-Nevada, USA) has experienced no natural recruitment for decades and is maintained by harvesting naturally produced larvae from the lake, rearing them in protective custody, and repatriating them at sizes less vulnerable to predation.

View Article and Find Full Text PDF

A comprehensive taxonomic study is presented for the four genera and 286 species of the doryctine tribe Heterospilini occurring in Costa Rica. The tribe is represented almost entirely by the 280 species of the genus Heterospilus Haliday. Keys for identification of the genera and species are provided and the genera and species are described and illustrated.

View Article and Find Full Text PDF

Biological characters can be employed for both taxonomy and phylogenetics, but is conscripting characters for double duty a good idea? We explore the evolution of characters designed for taxonomic diagnosis in Costa Rican heterospiline wasps, a hyperdiverse lineage of parasitoid Braconidae, by mapping them to a robust multi-locus molecular phylogeny. We discover a strong positive relationship between the amount of evolutionary change a character undergoes and how broadly useful the characters are in the context of an interactive identification key--e.g.

View Article and Find Full Text PDF
Article Synopsis
  • The Aleiodes pallidator species-group is introduced, along with an identification key for the five species found in the U.S. and Canada.
  • Two new species are identified: Aleiodes martini from Florida and A. xanthoclypeus from Canada and Wisconsin, which have been studied on certain moths.
  • The text includes illustrations of the five species and summarizes their relationships with various host organisms.
View Article and Find Full Text PDF