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1. Optimising recovery of DNA from minimally invasive sampling methods: Efficacy of buccal swabs, preservation strategy and DNA extraction approaches for amphibian studies.

Author

Martin, R., Mullin, K. E., White, N. F. D., Grimason, N., Jehle, R., Wilkinson, J. W., Orozco‐terWengel, P., Cunningham, A. A., and Maddock, S. T.

Subjects
NUCLEIC acid isolation methods, GENETIC techniques, BODY size, COLD storage, STORAGE facilities
Abstract

Studies in evolution, ecology and conservation are increasingly based on genetic and genomic data. With increased focus on molecular approaches, ethical concerns about destructive or more invasive techniques need to be considered, with a push for minimally invasive sampling to be optimised. Buccal swabs have been increasingly used to collect DNA in a number of taxa, including amphibians. However, DNA yield and purity from swabs are often low, limiting its use. In this study, we compare different types of swabs, preservation method and storage, and DNA extraction techniques in three case studies to assess the optimal approach for recovering DNA in anurans. Out of the five different types of swabs that we tested, Isohelix MS‐02 and Rapidry swabs generated higher DNA yields than other swabs. When comparing storage buffers, ethanol is a better preservative than a non‐alcoholic alternative. Dried samples resulted in similar or better final DNA yields compared to ethanol‐fixed samples if kept cool. DNA extraction via a Qiagen™ DNeasy Blood and Tissue Kit and McHale's salting‐out extraction method resulted in similar DNA yields but the Qiagen™ kit extracts contained less contamination. We also found that samples have better DNA recovery if they are frozen as soon as possible after collection. We provide recommendations for sample collection and extraction under different conditions, including budgetary considerations, size of individual animal sampled, access to cold storage facilities and DNA extraction methodology. Maximising efficacy of all of these factors for better DNA recovery will allow buccal swabs to be used for genetic and genomic studies in a range of vertebrates. [ABSTRACT FROM AUTHOR]

Published
2024
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2. Systematics and phylogeography of Seychelles amphibians

Author

Maddock, S. T., Day, J., and Gower, D.

Subjects
597.809696
Abstract

This thesis investigates evolutionary patterns of variation in endemic amphibians from the Seychelles archipelago. Focal groups include the treefrog (Tachycnemis seychellensis), and a radiation of caecilians in three genera (Grandisonia, Hypogeophis and Praslinia), and attempts to place these into a phylogenetic context. The introduction (Chapter 1) discusses the importance of islands in the study of evolution and examines patterns of intraspecific variation that have been reported in other Seychelles organisms. Chapter 2 provides the first intraspecific molecular study of the monotypic Seychelles treefrog Tachycnemis, implementing a species tree approach in order to investigate its relationship with its closest living relatives (Heterixalus) from Madagascar and test whether its ancestor colonised the Seychelles via overseas dispersal. Chapters 3 and 4 explore variation in the six species of Seychelles caecilian, all of which overlap in range on at least one island. To assess within- and among-island intraspecific variation in these subterranean amphibians, Chapter 3 uses genetic data from both mitochondrial and nuclear markers, while Chapter 4 uses morphometric and meristic data. Differing patterns of geographic structure was observed among the caecilian species. The final two data chapters analyse species-level relationships among the Seychelles caecilians. Chapter 5 utilises Next Generation Sequencing to obtain mitogenomic data, and multiple approaches to infer phylogeny, and the effectiveness of alternative methods are evaluated. Chapter 6 attempts to resolve relationships of the island caecilians using 11 nuclear loci and multiple methods of phylogenetic inference. Chapter 7 discusses how the thesis has increased knowledge of the study taxa and of the evolution of amphibians on islands, particularly the Seychelles.

Published
2016

11. Chytrid Fungus (Batrachochytrium dendrobatidis) Undetected in the Two Orders of Seychelles Amphibians

Author

Labisko, J., Maddock, S. T., Taylor, M. L., Chong-Seng, L, Gower, D. J., Wynne, F. J., Wombwell, E., Morel, C., French, G. C. A., Bunbury, N., and Bradfield, K. S.

Subjects
QL, animal structures, QH, parasitic diseases, QH75, geographic locations
Abstract

Reports the first disease screening for chytrid Fungus (Batrachochytrium dendrobatidis) in amphibians across the Seychelles Archipelago

Published
2015

12. A Tribute to Roger Covell

Author

Fabian, D, Maddock, S, Fabian, D, and Maddock, S

Abstract

A biographical tribute to Emeritus Professor Roger Covell (UNSW Australia 1966-2013), Fellow of the Australian Academy of Humanities (since 1983), founder and musical director of UNSW Opera, and chief music critic of the Sydney Morning Herald

Published
2016

13. Roger Covell at 85: A Tribute by his Colleagues and Students

Author

Fabian, D, Maddock, S, Fabian, D, and Maddock, S

Abstract

The volume includes a biographical tribute to Roger Covell, Emeritus Professor (UNSW 1966-2013), Fellow of the Australian Academy of Humanities (since 1983) and chief music critic of the Sydney Morning Herald (1960-2001). It also contains the abstracts of the 18 conference presentations, the full program of the day of celebrations and many photographs.

Published
2016

19. Creating Finite Element Models of Facial Soft Tissue

Author

Warburton, M., Maddock, S., and Skala, Václav

Subjects
modelování obličeje, face modelling, metoda konečných prvků, modelování měkkých tkání, physically-based animation, finite element method, fyzikální animace, physically-based modelling, soft-tissue modelling, fyzikální modelování, ComputingMethodologies_COMPUTERGRAPHICS
Abstract

Physically-based animation techniques enable more realistic and accurate animation to be created. Such approaches require the creation of a complex simulation model that, for computer graphics applications, can efficiently produce realistic-looking animations. We present a process to automatically create animatable nonconforming hexahedral finite element (FE) simulation models of facial soft tissue, including automatic computation of skin layers and element material properties, muscle properties and boundary conditions, making them immediately ready for simulation. Using the GPU, the detailed models can simulate complex gross and fine-scale behaviour, such as wrinkling. Our process can also be used to create a multi-layered FE model of any object (not just soft tissue).

Published
2013

32. Reactions of Perfluoroisopropyl Iodide with Cyclopentadienyl−Rhodium Complexes in Methanol. An Unexpected Route to a Rhodium−Fulvalene Complex

Author

Hughes, R. P., Husebo, T. L., Maddock, S. M., Liable-Sands, L. M., and Rheingold, A. L.

Abstract

Reaction of perfluoroisopropyl iodide with Rh(C5H5)(PMe3)2 generates a perfluorocarbanion intermediate along with [Rh(C5H5)(PMe3)2I]+, which react to give fluoroalkylation of the cyclopentadienyl ring. When the intermediate fluorocarbanion is trapped by CH3OD to give (CF3)2CFD, the resultant methoxide anion reacts with [Rh(C5H5)(PMe3)2I]+ to give a dinuclear fulvalene complex that has been characterized crystallographically.

Published
2002

33. Palladium-Catalyzed Head-to-Head Telomerization of Isoprene with Amines

Author

Maddock, S. M. and Finn, M. G.

Abstract

The palladium complex of tris(2,4,6-trimethoxyphenyl)phosphine (TTMPP) catalyzes the telomerization of isoprene with several secondary amines with unprecedented levels of selectivity for the head-to-head isomer. A mechanism based on stereoelectronic control by a Pd−monophosphine adduct is proposed.

Published
2000

34. Examination of Metal−Silicon Bonding through Structural and Theoretical Studies of an Isostructural Set of Five-Coordinate Silyl Complexes, Os(SiR<INF>3</INF>)Cl(CO)(PPh<INF>3</INF>)<INF>2</INF> (R = F, Cl, OH, Me)

Author

Hubler, K., Hunt, P. A., Maddock, S. M., Rickard, C. E. F., Roper, W. R., Salter, D. M., Schwerdtfeger, P., and Wright, L. J.

Abstract

Os(SiCl3)Cl(CO)(PPh3)2 is prepared by treatment of OsPhCl(CO)(PPh3)2 with excess HSiCl3 and serves in turn as the starting material for the syntheses of three more five-coordinate silyl complexes Os(SiR3)Cl(CO)(PPh3)2 (R = F, OH, Me) via substitution of the chloride groups on silicon. All four compounds were fully characterized, including a single-crystal solid-state structure of each derivative. Carbonyl stretching frequencies decrease and Os−Si bond lengths increase as R changes in the order from F to Cl to OH to Me. Ab initio calculations were performed on the model complexes Os(SiR3)Cl(CO)(PH3)2 (R = F, Cl, OH, Me) to explain the trends observed in the IR and X-ray studies, and the importance of the π-acceptor capacities of the silyl groups are discussed.

Published
1997

37. Insertion of Ethyne into the Ru−Si Bonds of Coordinatively Unsaturated Ruthenium Silyl Complexes. X-ray Crystal Structures of Ru(CH&dbd;CHSiMe<INF>2</INF>OEt)Cl(CO)<INF>2</INF>(PPh<INF>3</INF>)<INF>2</INF> and [Ru(CH&dbd;CHSiMe<INF>2</INF>OH)(CN-p-tolyl)(CO)(PPh<INF>3</INF>)<INF>2</INF>]ClO<INF>4</INF>

Author

Maddock, S. M., Rickard, C. E. F., Roper, W. R., and Wright, L. J.

Abstract

The five-coordinate silyl complexes Ru(SiR3)Cl(CO)(PPh3)2(R3 = Me3 (1a), Et3 (1b), Ph3 (1c), Me2Cl (1f)) are conveniently prepared through reaction of Ru(Ph)Cl(CO)(PPh3)2 with the appropriate silane, HSiR3. Reaction of the Si−Cl bond in 1f with ethanol or hydroxide gives the corresponding ethoxysilyl or hydroxysilyl products Ru(SiMe2X)Cl(CO)(PPh3)2 (X = OEt (1d), OH (1e)). Ethyne readily inserts into the Ru−Si bond of 1a−d, and the corresponding five-coordinate, silylalkenyl complexes Ru(CH&dbd;CHSiR3)Cl(CO)(PPh3)2 (R3 = Me3 (2a), Et3 (2b), Ph3 (2c), Me2OEt (2d)) can be isolated in good yield. The complexes Ru(CH&dbd;CHSiR3)Cl(CO)2(PPh3)2 (SiR3 = SiMe3 (3a), SiEt3 (3b), SiMe2OEt (3d)) result from carbonylation of 2a,b,d. An X-ray crystal structure determination of Ru(CH&dbd;CHSiMe2OEt)Cl(CO)2(PPh3)2 (3d) has been obtained. Reaction of Ru(CH&dbd;CHSiMe3)Cl(CO)(PPh3)2 (2a) with CN-p-tolyl or sodium acetate gives Ru(CH&dbd;CHSiMe3)Cl(CO)(CN-p-tolyl)(PPh3)2 (4a) or Ru(CH&dbd;CHSiMe3)(η2-O2CCH3)(CO)(PPh3)2 (5a), respectively. Insertion of ethyne into the Ru−Si bond of 1e results in the formation of the metallacyclic ring-containing complex, Ru(CH&dbd;CHSiMe2OH)Cl(CO)(PPh3)2 (6e), in which the hydroxysilyl oxygen atom is coordinated to ruthenium. Reaction of 6e with AgClO4 gives [Ru(CH&dbd;CHSiMe2OH)(CO)(NCMe)(PPh3)2]ClO4 (7e) and substitution of the labile acetonitrile in this compound with CO or CN-p-tolyl generates [Ru(CH&dbd;CHSiMe2OH)(CO)2(PPh3)2]ClO4 (8e) or [Ru(CH&dbd;CHSiMe2OH)(CO)(CN-p-tolyl)(PPh3)2]ClO4 (9e), respectively. The crystal structure of 9e has been determined. Deprotonation of 8e or 9e with KOH gives the neutral complexes Ru(CH&dbd;CHSiMe2O)(CO)2(PPh3)2 (10e) or Ru(CH&dbd;CHSiMe2O)(CO)(CN-p-tolyl)(PPh3)2 (11e), respectively. Complex 1b has been shown to catalyze the hydrosilylation of both ethyne and phenylethyne by HSiEt3.

Published
1996

38. PROLONGED INSULIN HYPOGLYCEMIA WITHOUT SYMPTOMS

Author

MADDOCK, S. J. and TRIMBLE, HARRY C.

Abstract

In connection with some experiments on the corpuscle-plasma distribution as related to insulin shock,1 we were particularly impressed by the length of time that hypoglycemia can exist before symptoms appear. On searching the literature for records of cases with prolonged hypoglycemia following single doses of insulin given subcutaneously, we were surprised to find very few examples in which blood sugar determinations were made frequently enough to give an accurate idea of the curve. There are no complete publications in which the blood sugar curves in man have been carefully followed to the point of a reaction, such as are recorded for the ordinary laboratory animals. The only available information of this nature is to be found incorporated into various studies made for other purposes and in cases in which the reactions came as rare accidents in the procedure. Most of the strictly clinical papers present figures obtained after the

Published
1928
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40. HMX: 13 Week Toxicity Study in Mice by Dietary Administration

Author

INVERESK RESEARCH INTERNATIONAL LTD MUSSELBURGH (UNITED KINGDOM), Everett, D. J., Maddock, S. M., INVERESK RESEARCH INTERNATIONAL LTD MUSSELBURGH (UNITED KINGDOM), Everett, D. J., and Maddock, S. M.

Abstract

Mice were fed diets containing HMX for 13 weeks. Dose levels for males were 0, 5, 12, 30, 75 or 200 mg HMX/kg/day. Female mice received 0, 10, 30, 90, 250 or 750 mg HMX/kg/day. Mortalities attributable to HMX at 200 mg HMX/ kg/day amongst males and at 250 and 750 mg HMX/kg/day amongst females. Occasional deaths at lower dose levels were of uncertain aetiology. No marked effects on body weight were noted although food consumption was reduced amongst higher dosed males and females. There were slight but equivocal changes in haematological and clinical chemical observations. Neither gross autopsy nor histopathology revealed any findings likely to be associated with the administration of HMX.

Published
1985

41. Novel ways of manipulating plants

Author

Miflin, B., Jones, M., Ooms, G., Karp, A., Maddock, S., Bright, S., Miflin, B., Jones, M., Ooms, G., Karp, A., Maddock, S., and Bright, S.

Abstract

Meeting abstract

Published
1985

43. Segmenting biological specimens from photos to understand the evolution of UV plumage in passerine birds

Author

He, Y., Cooney, C.R., Varley, Z.K., Nouri, L.O., Moody, C.J.A., Jardine, M.D., Maddock, S., and Thomas, G.H.

Abstract

Ultraviolet (UV) colouration is thought to be an important signalling mechanism in many bird species, yet broad insights regarding the prevalence of UV plumage colouration and the factors promoting its evolution are currently lacking. Here, we develop a novel image segmentation pipeline based on deep learning that considerably outperforms classical (i.e. non-deep learning) segmentation methods, and use this to extract accurate information on whole-body plumage colouration from photographs of >24,000 museum specimens covering >4,500 species of passerine birds. Our results demonstrate that UV reflectance, particularly as a component of other colours, is widespread across the passerine radiation but is strongly phylogenetically conserved. We also find clear evidence in support of the role of light environment in promoting the evolution of UV plumage colouration, and a weak trend towards higher UV plumage reflectance among bird species with ultraviolet rather than violet-sensitive visual systems. Overall, our study provides important broad-scale insight into an enigmatic component of avian colouration, as well as demonstrating that deep learning has considerable promise for allowing new data to be bought to bear on long-standing questions in ecology and evolution.

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