Engineering novel complement activity into a pulmonary surfactant protein

Complement neutralizes invading pathogens, stimulates inflammatory and adaptive immune responses, and targets non- or altered-self structures for clearance. In the classical and lectin activation pathways, it is initiated when complexes composed of separate recognition and activation subcomponents bind to a pathogen surface. Despite its apparent complexity, recognition-mediated activation has evolved independently in three separate protein families, C1q, mannose-binding lectins (MBLs), and serum ficolins. Although unrelated, all have bouquet-like architectures and associate with complement-specific serine proteases: MBLs and ficolins with MBL-associated serine protease-2 (MASP-2) and C1q with C1r and C1s. To examine the structural requirements for complement activation, we have created a number of novel recombinant rat MBLs in which the position and orientation of the MASP-binding sites have been changed. We have also engineered MASP binding into a pulmonary surfactant protein (SP-A), which has the same domain structure and architecture as MBL but lacks any intrinsic complement activity. The data reveal that complement activity is remarkably tolerant to changes in the size and orientation of the collagenous stalks of MBL, implying considerable rotational and conformational flexibility in unbound MBL. Furthermore, novel complement activity is introduced concurrently with MASP binding in SP-A but is uncontrolled and occurs even in the absence of a carbohydrate target. Thus, the active rather than the zymogen state is default in lectin·MASP complexes and must be inhibited through additional regions in circulating MBLs until triggered by pathogen recognition

Study of the coordination chemistry of phosphinines and phosphabarrelenes

The syntheses of a series of 2,6-(2'-haloaryl)-4-tolylphosphinines, ranging from the fluoro, chloro, bromo and iodo derivatives, as well as the 2,6-dixylyl-4- phenylphosphinine ligand are reported. The coordination chemistry of these ligands has been evaluated by coordinating them to pentacarbonyltungsten(O), to form the complex W(CO)s(L), where L = fluoro, choloro, bromo, iodo or dixylyl derivatives of the phosphinine secondly to Rh(COD)Cl 2, to form the complex Rh(COD)Cl(L), where COD = 1,5-cyclooctadiene, and L= fluoro, chloro, bromo or dixylyl derivatives of the phosphinine and thirdly to Rh(CO)2Cl 2 to form Rh(CO)Cl(L) 2, where L = 2,6,-dixylyl-4-phenylphosphinine only. These complexes were fully characterised by spectroscopic means, their coordination chemistry studied and the metal-phosphorus bond in these complexes is elucidated by comparison to analogous complexes of phosphines, and phosphites. Finally the 2,6-dixylyl-4-phenylphosphabarrelene is synthesised from its parent phosphinine, and applied in a survey of transition metal complexes to evaluate its properties as a ligand. The complexes made were W(CO)s(L), Re(CO)4Cl(L), Ru(cymene)(L)Cl2, Fe(r 5-C5H4SiMe3)(CO)2L + PF6", Rh(CO)Cl(L)2, Rh(COD)Cl(L), Ir(COD)Cl(L), PtCl2(L)2, Ag(L)2 + Tf Cu(L)Cl, and Pd(L). Where L = 2,6-dixylyl-4-phenylphosphabarrelene, cymene = 4-isopropyltoluene, Cp = cyclopentadienyl and COD = 1,5-cyclooctadiene are described. The coordination chemistry of the phosphabarrelene was established and the nature of the phosphorus- metal bond in each complex was elucidated by comparison to analogous complexes of triarylphosphines and triarylphosphites. In addition the phosphabarrelene was tested in the rhodium catalysed hydroformylation of 4-octene, in comparison with the commonly used (2,4-di-t-butylphenyl)phosphite.EThOS - Electronic Theses Online ServiceGBUnited Kingdo

A comparison study of the blower door and novel pulse technique on measuring enclosure airtightness in a controlled environment

This paper introduces a comparison study of measuring the airtightness of a house sized test chamber using the novel pulse technique and the standard blower door method in a controlled environment. Eight different testing plates have been applied to the improvised envelope of the chamber to establish different leakage characteristics. Each testing plate has a unique opening in the centre of the plate, achieved by obtaining a different combination of shape and thickness of the opening. By using the controlled environment, the vagaries of the natural condition when testing within buildings have been reduced providing a more robust testing environment. This investigation focuses on how the air leakage rate calculated from the measurements made by both techniques compare with each other. Comparable results (within 3 %) under most scenarios have been obtained. Additionally, other aspects such as usability of the equipment used for the pulse testing have also been appraised

Airtightness measurement of an outdoor chamber using the Pulse and blower door methods under various wind and leakage scenarios

As a continued investigation following the previous testing of a house-sized chamber in a sheltered environment, this paper introduces an experimental study of airtightness measurement of an outdoor chamber using both the novel Pulse technique and the steady pressurisation method. The chamber has dimensions of approximately half that of a standard 20ft long shipping container. The chamber’s envelope was modified with multiple openings to provide a leakage level similar to that of an average UK house. Two sets of experimental tests were carried out independently at different times to investigate: a) How both methods compare on measuring the airtightness of an outdoor chamber at various leakage levels; and b) How the steady wind at various wind speed may affect the Pulse measurement of the chamber airtightness. Results show that the air permeability at 4 Pa measured by both methods has a percentage difference less than 16% in most testing scenarios, which is a slightly larger discrepancy than that found in the sheltered environment study. In steady wind tests, artificial wind at various speed levels was introduced in the Pulse tests by utilising a multi-gear portable trailer fan. Initial findings have shown that the impact of steady wind on the Pulse test is mostly insignificant when it is under 3.5 m/s. However, high wind speeds (4 m/s-9.5 m/s) decrease the value of air permeability at 4 Pa by 16%-24% in comparison to that measured under the fan-off condition in the steady wind tests

Experimental study of enclosure airtightness of an outdoor chamber using the pulse technique and blower door method under various leakage and wind conditions

This paper introduces an experimental study of enclosure airtightness testing of an outdoor chamber using both the pulse technique and the blower door method. This investigation is a 2nd stage comparison study following the previous testing of a house-sized chamber in a sheltered environment. The outdoor chamber in this study has dimensions, approximately half that of a standard 20ft long shipping container. Multiple openings were installed into the chamber’s envelope to provide a leakage level and characteristics similar to an average UK house. Two sets of experimental tests were carried out independently at different times to investigate: a) How the pulse technique and blower door method compare on measuring enclosure airtightness of an outdoor chamber at various leakage levels; b) How the steady wind at various wind speed affects the measurement of chamber airtightness using the pulse technique. The comparison tests were performed in the chamber with various leakage levels achieved by sealing up different vents. Both blower door and pulse have given comparable results (±16%) of air permeability at 4 Pa in most testing scenarios, which is a slightly larger discrepancy than that found in the previous sheltered environment study. In the steady wind tests, the external fabric of the chamber was subjected to wind at various wind speed levels, by utilising a multi-gear portable trailer fan. Initial findings have shown that the impact of steady wind on the measurement of chamber airtightness using the pulse technique is mostly insignificant when it is under 3.5 m/s. The measured air permeability at 4 Pa (P4) at high wind speed (4 m/s - 9.5 m/s) in one direction is 16%-24% less than that measured under fan off condition in the steady wind tests

The paleobiogeographical significance of the Silurian and Devonian trilobites of Japan

Six major groups of trilobites from the Silurian and Devonian of Japan are evaluated for their paleobiogeographical signature. Silurian illaenids and scutelluids show four generic-level and at least two species-level links with the Australian segment of the Gondwana paleocontinent; encrinurids also indicate two generic-level links with Australia and also the South China paleocontinent; whilst Devonian phacopids, and possibly proetids, suggest at least two generic-level links with the North China paleocontinent. These different patterns may reflect the fragmentary biostratigraphical record of Japanese trilobites, but they also appear to reflect paleoenvironmental parameters associated with lithofacies, and paleoecology. Thus, Japanese assemblages of proetids and phacopids occurring in deep-water clastic lithofacies have counterparts in similar settings in North China, and Japanese scutelluids and illaenids are strongly associated with shallow marine carbonate lithofacies that are similar to those of their occurrences in Australia. Japanese encrinurids occur in carbonate rocks indicative of shallow marine settings in the Kurosegawa Terrane, and they demonstrate a consistent paleobiogeographical affinity with Australia and South China. Larval ecology cannot be directly assessed for Japanese trilobite groups. However, proetids have consistently been shown to have planktonic protaspides, whereas illaenids, scutelluids, and encrinurids have benthic protaspides. Planktonic protaspides would have a greater propensity for distribution in ocean currents than benthic ones, and therefore may be of more limited paleobiogeographical utility. The combined data from the six different groups indicates that the complex paleobiogeographical patterns of the Japanese trilobite assemblages need to be interpreted with caution, and similarity of taxa does not necessarily denote paleogeographical proximity to other regions

Ctrl-P:Temporal control of prosodic variation for speech synthesis

Text does not fully specify the spoken form, so text-to-speech models must be able to learn from speech data that vary in ways not explained by the corresponding text. One way to reduce the amount of unexplained variation in training data is to provide acoustic information as an additional learning signal. When generating speech, modifying this acoustic information enables multiple distinct renditions of a text to be produced. Since much of the unexplained variation is in the prosody, we propose a model that generates speech explicitly conditioned on the three primary acoustic correlates of prosody: $F_{0}$, energy and duration. The model is flexible about how the values of these features are specified: they can be externally provided, or predicted from text, or predicted then subsequently modified. Compared to a model that employs a variational auto-encoder to learn unsupervised latent features, our model provides more interpretable, temporally-precise, and disentangled control. When automatically predicting the acoustic features from text, it generates speech that is more natural than that from a Tacotron 2 model with reference encoder. Subsequent human-in-the-loop modification of the predicted acoustic features can significantly further increase naturalness.Comment: To be published in Interspeech 2021. 5 pages, 4 figure

Direct radiocarbon dating of fish otoliths from mulloway (Argyrosomus japonicus) and black bream (Acanthopagrus butcheri) from Long Point, Coorong, South Australia

Accelerator Mass Spectrometry (AMS) radiocarbon dates (n=20) determined on fish otoliths from mulloway (Argyrosomus japonicus) and black bream (Acanthopagrus butcheri) are reported from five sites at Long Point, Coorong, South Australia. The dates range from 2938–2529 to 326–1 cal. BP, extending the known period of occupation of Long Point. Previous dating at the sites indicated intensive occupation of the area from 2455–2134 cal. BP. Results provide a detailed local chronology for the region, contributing to a more comprehensive understanding of Aboriginal use of Ngarrindjeri lands and waters. This study validates the use of fish otoliths for radiocarbon dating and reveals how dating different materials can result in different midden chronologies

Effects of early life exposure to traffic-related air pollution on brain development in juvenile Sprague-Dawley rats

Epidemiological studies link traffic-related air pollution (TRAP) to increased risk for various neurodevelopmental disorders (NDDs); however, there are limited preclinical data demonstrating a causal relationship between TRAP and adverse neurodevelopmental outcomes. Moreover, much of the preclinical literature reports effects of concentrated ambient particles or diesel exhaust that do not recapitulate the complexity of real-world TRAP exposures. To assess the developmental neurotoxicity of more realistic TRAP exposures, we exposed male and female rats during gestation and early postnatal development to TRAP drawn directly from a traffic tunnel in Northern California and delivered to animals in real-time. We compared NDD-relevant neuropathological outcomes at postnatal days 51-55 in TRAP-exposed animals versus control subjects exposed to filtered air. As indicated by immunohistochemical analyses, TRAP significantly increased microglial infiltration in the CA1 hippocampus, but decreased astrogliosis in the dentate gyrus. TRAP exposure had no persistent effect on pro-inflammatory cytokine levels in the male or female brain, but did significantly elevate the anti-inflammatory cytokine IL-10 in females. In male rats, TRAP significantly increased hippocampal neurogenesis, while in females, TRAP increased granule cell layer width. TRAP had no effect on apoptosis in either sex. Magnetic resonance imaging revealed that TRAP-exposed females, but not males, also exhibited decreased lateral ventricular volume, which was correlated with increased granule cell layer width in the hippocampus in females. Collectively, these data indicate that exposure to real-world levels of TRAP during gestation and early postnatal development modulate neurodevelopment, corroborating epidemiological evidence of an association between TRAP exposure and increased risk of NDDs