The astacin metalloprotease moulting enzyme NAS-36 is required for normal cuticle ecdysis in free-living and parasitic nematodes

Nematodes represent one of the most abundant and species-rich groups of animals on the planet, with parasitic species causing chronic, debilitating infections in both livestock and humans worldwide. The prevalence and success of the nematodes is a direct consequence of the exceptionally protective properties of their cuticle. The synthesis of this cuticle is a complex multi-step process, which is repeated 4 times from hatchling to adult and has been investigated in detail in the free-living nematode, Caenorhabditis elegans. This process is known as moulting and involves numerous enzymes in the synthesis and degradation of the collagenous matrix. The nas-36 and nas-37 genes in C. elegans encode functionally conserved enzymes of the astacin metalloprotease family which, when mutated, result in a phenotype associated with the late-stage moulting defects, namely the inability to remove the preceding cuticle. Extensive genome searches in the gastrointestinal nematode of sheep, Haemonchus contortus, and in the filarial nematode of humans, Brugia malayi, identified NAS-36 but not NAS-37 homologues. Significantly, the nas-36 gene from B. malayi could successfully complement the moult defects associated with C. elegans nas-36, nas-37 and nas-36/nas-37 double mutants, suggesting a conserved function for NAS-36 between these diverse nematode species. This conservation between species was further indicated when the recombinant enzymes demonstrated a similar range of inhibitable metalloprotease activities

The supply services of the British army in the South African War, 1899-1902

The purpose of this study is to analyse the methods and results of the supply services of the British army in the South African war. The study will consider both the preparations made for the war and the changes made after it and covers administration both in the War Office and with the army in the field. It tries to show how the complex task of moving the army and providing it with transport, arms, stores, food and animals needed to keep it effective was performed, and to what extent the material provided met the needs of the army both in quality and in quantity. Continued in thesis ...

Covid-19 Effects on Commodity Pricing

My work is based on how COVID-19 has affected commodity prices around the world. Commodities are something we use and depend on every day whether we realize it or not and I was curious to see how this is affected by major world events. I focused my research on four separate commodities, steel, crude oil, lumber, and wheat. I gathered the spot prices for each commodity dating back to 2009 and broke the data down weekly. After normalizing the data, I graphed the results to see if they were all affected the same way. What I found was that demand during 2020 was extremely high partial due to people stockpiling items in fear of having to quarantine. What I further found was that this was one of the many reasons demands rose and reflected onto spot prices. There was also extreme variation between all of the commodities I chose. This went against my initial idea that the commodities would track each other in some way. I also found that wheat is affected hugely by the recent war between Ukraine and Russia due to Ukraine producing 10% of the world trade for this commodity

Stellar Superfluids

Neutron stars provide a fertile environment for exploring superfluidity under extreme conditions. It is not surprising that Cooper pairing occurs in dense matter since nucleon pairing is observed in nuclei as energy differences between even-even and odd-even nuclei. Since superfluids and superconductors in neutron stars profoundly affect neutrino emissivities and specific heats, their presence can be observed in the thermal evolution of neutron stars. An ever-growing number of cooling neutron stars, now amounting to 13 thermal sources, and several additional objects from which upper limits to temperatures can be ascertained, can now be used to discriminate among theoretical scenarios and even to dramatically restrict properties of nucleon pairing at high densities. In addition, observations of pulsars, including their spin-downs and glitch histories, additionally support the conjecture that superfluidity and superconductivity are ubiquitous within, and important to our understanding of, neutron stars.Comment: 88 pages, 35 figures. Some new references added. To be published in the book "Novel Superfluids", Eds. K. H. Bennemann and J. B. Ketterson (Oxford University Press

Adult Education and Technology in a Rural County: The Irony of Persistent Poverty and ‘Progress’ in the Information Age

Information and communication technologies (ICTs) have brought many new challenges for adult education. In this qualitative study, a framework is proposed to address the disparity known as the Digital Divide in a persistently impoverished rural county in the southern United States

Iran, America and Iranian American Community in Firoozeh Jazayeri Dumas\u27 Funny in Farsi

Post 9/11 the United States of America concerns the reconstruction of already demonized identities of Arabs and Middle-eastern cultures. Postcolonial works reside in their rendering a tragic or serious image of Middle Easterners to bring the Western (American) audience into sympathizing with the Middle Eastern ethnicities. Could it be the case that a fundamentally humorous (not derogatory) depiction might contribute to easing such cultural tensions? Firoozeh Jazayeri Dumas\u27 works stand out as critically acclaimed and successful works familiarizing the American audience with the more humane, likeable, sweet and funny aspects of the Iranians and Iranian culture, and the hardships of being an Iranian immigrant and becoming a hybrid individual. This article explores the already-hybridized self and psyche of Firoozeh as an Iranian American. She writes about her mother land and her residence country and comparing the way she has written about them can help readers understand how one can make peace between different parts of her identity

Exploring the free-energy landscape of a rotating superfluid

The equilibrium state of a superfluid in a rotating cylindrical vessel is a vortex crystal -- an array of vortex lines which is stationary in the rotating frame. Experimental realisations of this behaviour typically show a sequence of transient states before the free-energy minimising configuration is reached. Motivated by these observations, we construct a new method for a systematic exploration of the free-energy landscape via gradient-based optimisation of a scalar loss function. Our approach is inspired by the pioneering numerical work of Campbell & Ziff (Phys. Rev. B 20, 1979), and makes use of automatic differentiation (AD) which crucially allows us to include entire solution trajectories in the loss. We first use the method to converge thousands of low-free-energy relative equilibria for vortex numbers in the range $10 \leq N \leq 30$, which reveals an extremely dense set of mostly saddle-like solutions. As part of this search, we discover new continuous families of relative equilibria (in the unbounded domain) which are often global minimisers of the free energy. These continuous families all consist of crystals arranged in a double-ring configuration, and we assess which state from the family is most likely to be observed experimentally by computing energy-minimising pathways from nearby local minima -- identifying a common entry point into the family. Finally, we develop an approach to compute homoclinic orbits and use it to examine the dynamics in the vicinity of the minimising state by converging connections for low-energy saddles.Comment: 13 pages, 12 figure

Biosynthesis and enzymology of the Caenorhabditis elegans cuticle: identification and characterization of a novel serine protease inhibitor.

The nematode Caenorhabditis elegans represents an excellent model in which to examine nematode gene expression and function. A completed genome, straightforward transgenesis, available mutants and practical genome-wide RNAi approaches provide an invaluable toolkit in the characterization of nematode genes. We have performed a targeted RNAi screen in an attempt to identify components of the cuticle collagen biosynthetic pathway. Collagen biosynthesis and cuticle assembly are multi-step processes that involve numerous key enzymes involved in post-translational modification, trimer folding, procollagen processing and subsequent cross-linking stages. Many of these steps, the modifications and the enzymes are unique to nematodes and may represent attractive targets for the control of parasitic nematodes. A novel serine protease inhibitor was uncovered during our targeted screen, which is involved in collagen maturation, proper cuticle assembly and the moulting process. We have confirmed a link between this inhibitor and the previously uncharacterized bli-5 locus in C. elegans. The mutant phenotype, spatial expression pattern and the over-expression phenotype of the BLI-5 protease inhibitor and their relevance to collagen biosynthesis are discussed