The tetrapod Caerorhachis bairdi Holmes and Carroll from the Lower Carboniferous of Scotland

The tetrapod Caerorhachis bairdi, probably from the Pendleian Limestone Coal Group in the Scottish Midland Valley, is redi agnosed and redescribed, and its affinities are discussed. Caerorachis was originally interpreted as a temnospondyl amphibian, based on characters that are now regarded as primitive for tetrapods, or of uncertain polarity. Several features of Caerorhachis (e.g. gastrocentrous vertebrae, curved trunk ribs, reduced dorsal iliac blade, L-shaped tarsal intermedium) are observed in certain primitive amniotes. In particular, Caerorhachis resembles ‘anthracosaurs’, generally considered to be among the most primitive of stem-group amniotes. The phylogenetic position of Caerorhachis is considered in the light of recently published cladistic analyses of Palaeozoic tetrapods. Most analyses place Caerorhachis at the base of, or within, ‘anthra- cosaurs’. When multiple, equally parsimonious solutions are found, its ‘anthracosaur’ affinities are shown in at least some trees, and are supported by several informative and, generally, highly consistent characters. Alternative phylogenetic placements (e.g. sister taxon to temnospondyls) are usually less well corroborated. If the fundamental evolutionary split of most early tetrapods into stem-group lissamphibians (e.g. temnospondyl s) and stem-group amniotes (e.g. ‘anthracosaurs’) is accepted, then the revised interpretation of Caerorhachi s sheds light on near-ancestral conditions for Amniota

Fintech: how and is it being taught in academia?

Merriam Webster defines Fintech as “products and companies that employ newly developed digital and online technologies in the banking and financial services industries” (Merriam-Webster). Fintech, short for financial technology, is not new; however, it has become a hot topic as of recently. During the pandemic, Fintech and the many apps and programs that make up financial technology began to surge. Applications that made applying for loans and moving money easily between friends and businesses were of utmost importance during this time. Instant financial results and access are only continuing in demand. The days of going into a brick-and-mortar building and sitting with a person for a lengthy period to discuss your finances are starting to become outdated. However, even with the demand for Fintech and its abilities to streamline monetary transactions, the trust in the security of these applications is still low. Cumulatively, there has been over $7 billion stolen in the crypto space, so it is also clear that the cybersecurity of crypto and public trust in adoption is also an important topic (Thapa, 2022). Our data collection comprises of a survey that is sent out to the faculty at various schools to gather data about the current state of how Fintech is being taught at universities. In addition, we examine a plethora of academic journals to gather information about what is being taught, what should be taught and how the current state of Fintech in academia can be improved

Labelled transition systems as a Stone space

A fully abstract and universal domain model for modal transition systems and refinement is shown to be a maximal-points space model for the bisimulation quotient of labelled transition systems over a finite set of events. In this domain model we prove that this quotient is a Stone space whose compact, zero-dimensional, and ultra-metrizable Hausdorff topology measures the degree of bisimilarity such that image-finite labelled transition systems are dense. Using this compactness we show that the set of labelled transition systems that refine a modal transition system, its ''set of implementations'', is compact and derive a compactness theorem for Hennessy-Milner logic on such implementation sets. These results extend to systems that also have partially specified state propositions, unify existing denotational, operational, and metric semantics on partial processes, render robust consistency measures for modal transition systems, and yield an abstract interpretation of compact sets of labelled transition systems as Scott-closed sets of modal transition systems.Comment: Changes since v2: Metadata updat

Keeping up appearances: male fiddler crabs wave faster in a crowd

Courtship displays are often energetically and temporally costly as well as highly conspicuous to predators. Selection should therefore favour signalling tactics that minimize courtship costs while maintaining or increasing signal attractiveness. In fiddler crabs, males court females by waving their one greatly enlarged claw in a highly conspicuous and costly display. Here, we investigate whether courting males adjust their wave rate, and therefore the cost of courtship, to the current level of competition.We show that display rate increases as competition increases and that when competition is removed, males reduce their display rate by 30 per cent. These results suggest that male fiddler crabs actively reduce the cost of courtship by adjusting their wave rate in response to the immediate level of competition

Biophotonic Tools in Cell and Tissue Diagnostics.

In order to maintain the rapid advance of biophotonics in the U.S. and enhance our competitiveness worldwide, key measurement tools must be in place. As part of a wide-reaching effort to improve the U.S. technology base, the National Institute of Standards and Technology sponsored a workshop titled "Biophotonic tools for cell and tissue diagnostics." The workshop focused on diagnostic techniques involving the interaction between biological systems and photons. Through invited presentations by industry representatives and panel discussion, near- and far-term measurement needs were evaluated. As a result of this workshop, this document has been prepared on the measurement tools needed for biophotonic cell and tissue diagnostics. This will become a part of the larger measurement road-mapping effort to be presented to the Nation as an assessment of the U.S. Measurement System. The information will be used to highlight measurement needs to the community and to facilitate solutions

Development of an Aerobic Biocathode for Microbial Fuel

Ph.D.Microbial fuel cells (MFCs), which convert organic waste to electricity using microbes, could be used to make the wastewater infrastructure more energy efficient and sustainable. However, the chemical catalysts which catalyse the oxygen reduction reaction (ORR) at the cathode of MFCs are expensive and unsustainable. Mixed community aerobic biocathode biofilms are an alternative to chemical catalysts. However, little is known about the bacteria, their metabolism, and their mechanisms of electron transfer with the electrode. A novel 4-electrode method was used to determine the minimum potential for production of peroxide on a porous carbon felt biocathode support. Biocathodes with a high onset potential for the ORR of +0.4 V vs Ag/AgCl were then cultivated in poised-potential half-cells at working electrode potentials of -0.1 and +0.2 V vs Ag/AgCl. These biofilms show what may be an electrode potential-dependent switch in an electron transfer mechanism from -0.1 to +0.2 V vs Ag/AgCl. The biofilms were dominated by unidentified Gammaproteobacteria, not present in unpolarised controls, which were most likely responsible for the ORR catalysis. This is the first time that a link has been made between a high onset potential for ORR catalysis of +0.4 V vs Ag/AgCl, and the bacteria responsible for this catalysis. Using half-cells, the aerobic biocathodes were enriched and used to replace existing abiotic Pt cathodes in operational MFCs. MFC performance was found to be limited by high external resistance and oxygen mass transfer. The MFC with a biocathode achieved a 9-fold increase in peak power from 7 to 62 W/cm2 using a carbon electrode with a biocathode compared to a plain carbon electrode. A simple battery separator was shown to be as effective as an ion exchange membrane through novel abiotic analysis of this membrane, and the MFC with a battery separator was found to give similar performance to the MFC with an ion exchange membrane

A bi-functional siRNA construct induces RNA interference and also primes PCR amplification for its own quantification

RNA interference (RNAi) is a process of post-transcriptional gene silencing initiated by double-stranded RNAs, including short interfering RNA (siRNA). Silencing is sequence-specific and RNAi has rapidly become central to the study of gene function. RNAi also carries promise for selective silencing of viral and endogenous genes causal for disease. To detect the very low levels of siRNA effective for RNAi we modified the 3′ end of the sense strand of siRNA with a nuclease-resistant DNA hairpin. We show that the modified siRNA-DNA construct (termed ‘crook’ siRNA) functions as a primer for the PCR and describe a novel, yet simple PCR protocol for its quantification (amolar levels/cell). When transfected into mammalian cells, crook siRNA induces selective mRNA knock-down equivalent to its unmodified siRNA counterpart. This new bifunctional siRNA construct will enable future in vivo studies on the uptake, distribution and pharmacokinetics of siRNA, and is particularly important for the development of siRNA-based therapeutics. More generally, PCR-based detection of siRNA carries wide-ranging applications for RNAi reverse genetics

Soleus stretch reflex during cycling

The modulation and strength of the human soleus short latency stretch reflex was investigated by mechanically perturbing the ankle during an unconstrained pedaling task. Eight subjects pedaled at 60 rpm against a preload of 10 Nm. A torque pulse was applied to the crank at various positions during the crank cycle, producing ankle dorsiflexion perturbations of similar trajectory. The stretch reflex was greatest during the power phase of the crank cycle and was decreased to the level of background EMG during recovery. Matched perturbations were induced under static conditions at the same crank angle and background soleus EMG as recorded during the power phase of active pedaling. The magnitude of the stretch reflex was not statistically different from that during the static condition throughout the power phase of the movement. The results of this study indicate that the stretch reflex is not depressed during active cycling as has been shown with the H-reflex. This lack of depression may reflect a decreased susceptibility of the stretch reflex to inhibition, possibly originating from presynaptic mechanisms

Folding Langmuir Monolayers

The maximum pressure a two-dimensional surfactant monolayer is able to withstand is limited by the collapse instability towards formation of three-dimensional material. We propose a new description for reversible collapse based on a mathematical analogy between the formation of folds in surfactant monolayers and the formation of Griffith Cracks in solid plates under stress. The description, which is tested in a combined microscopy and rheology study of the collapse of a single-phase Langmuir monolayer of 2-hydroxy-tetracosanoic acid (2-OH TCA), provides a connection between the in-plane rheology of LM's and reversible folding