257 research outputs found
Learning From the Story of a Great Leader
This paper reports on research findings from a larger study which seeks to understand leadership from the experiences of well-known and well-recognised Australian leaders across a spectrum of endeavours such as the arts, business, science, the law and politics. To date there appears to be limited empirical research that has investigated the insights of Australian leaders regarding their leadership experiences, beliefs and practices. In this paper, the leadership story of a well-respected medical scientist is discussed revealing the contextual factors that influenced her thinking about leadership as well as the key values she embodies as a leader. The paper commences by briefly considering some of the salient leadership literature in the field. In particular, two prominent theoretical frameworks provided by Leavy (2003) and Kouzes and Posner (2002) are explored. While Leavy’s framework construes leadership as consisting of three “C’s‿ – context , conviction and credibility, Kouzes and Posner (2002) refer to five practices of exemplary leadership. The paper provides a snapshot of the life forces and context that played an important role in shaping the leader’s views and practices. An analytical discussion of these practices is considered in the light of the earlier frameworks identified. Some implications of the findings from this non-education context for those in schools are briefly noted
The biosystematics of British aquatic larval orthocladiinae (diptera: chironomidae)
PhDThe relationships and subfamilial classification of the
Chironomidae (Insecta: iptera, ematocera) are discussed and some
comments made on the ecological significance of the range of larval
habitats found in the family. The reasons are given for the
selection of the aquatic larval Orthocladiinae for detailed
morphological and ecological study.
Following a review of previous taxonomic works and an analysis
of the current views on the Orthocladiinae, a method for rearing
aquatic larval Chironomidae is described. This method utilises
disposable petri-dishes each containing a single larva, kept in
a cooled incubator. This is followed by a list of fifty-two
collecting sites throughout Britain with some physical and
biological data for each site.
Keys for the identification of the larvae of all known
Holarotic genera are presented based on reared British material
and incorporating published descriptions and examination of
overseas specimens. Generic diagnoses to forty-one British
genera of Orthocladiinae and descriptions and keys to ninety-one
aquatic species are given. These have been prepared from
examination of about 1,230 specimens, reared, collected and sent
by correspondents. For each genus the relationships and
phylogeny are discussed and for each species a full description
is given using morphological terminology outlined in a previous
chapter. Over four hundred illustrations in seventy-nine plates
show the features of each species, many for the first time.
Under each species all available ecological and
distributional information is given. Eleven species either
cannot be associated with adults or else appear to belong to
undescribed species.
In a concluding chapter the relationship between the
phylogeny and ecology of the subfamily is discussed incorporating
additionally information about genera with terrestrial and
marine larvae. The importance of species identification
especially for indicator organisms in pollution biology, as
well as for calculations of diversity in freshwater habitats,
is stressed
Evidence from molecules and morphology expands Podonomopsis Brundin (Diptera : Chironomidae : Podonominae) to include 'genus Chile'
The informal taxon ‘genus Chile’ of Brundin, based solely on pupal exuviae of a podonomine Chironomidae, has remained inadequately known for half a century. New collections reveal life associations, and provide molecular data to hypothesise a precise phylogenetic placement in the austral Podonominae. A densely sampled molecular phylogeny based on two nuclear and one mitochondrial DNA markers shows ‘genus Chile’ to be the sister group to Podonomopsis Brundin, 1966. Within Podonomopsis a clade of South American species is sister to all Australian species. We discuss how to rank such a sister group taxon and treat ‘genus Chile’ as a new subgenus Araucanopsis, subg. nov. with the new species, Podonomopsis (Araucanopsis) avelasse, sp. nov. from Chile and Argentina as genotype of the monotypic subgenus. We describe P. (A.) avelasse in all stages and provide an expanded diagnosis and description of Podonomopsis to include Araucanopsis. A dated biogeographic hypothesis (chronogram) infers the most recent common ancestor (tmcra) of expanded Podonomopsis at 95 million years ago (Mya) (68–122 Mya 95% highest posterior density), ‘core’ Podonomopsis at 83 Mya (58–108) and Australian Podonomopsis at 65 Mya (44–87). All dates are before the South America–Australia geological separation through Antarctica, supporting previous conclusions that the taxon distribution is ‘Gondwanan’ in origin. Podonomopsis, even as expanded here, remains unknown from New Zealand or elsewhere on extant Zealandia
Taxonomic review of the chironomid genus Cricotopus v.d. Wulp (Diptera: Chironomidae) from Australia: keys to males, females, pupae and larvae, description of ten new species and comments on Paratrichocladius Santos Abreu
The Australian species of the Orthocladiinae genus Cricotopus Wulp (Diptera: Chironomidae) are revised for larval, pupal, adult male and female life stages. Eleven species, ten of which are new, are recognised and keyed, namely Cricotopus acornis Drayson & Cranston sp. nov., Cricotopus albitarsis Hergstrom sp. nov., Cricotopus annuliventris (Skuse), Cricotopus brevicornis Drayson & Cranston sp. nov., Cricotopus conicornis Drayson & Cranston sp. nov., Cricotopus hillmani Drayson & Cranston, sp. nov., Cricotopus howensis Cranston sp. nov., Cricotopus parbicinctus Hergstrom sp. nov., Cricotopus tasmania Drayson & Cranston sp. nov., Cricotopus varicornis Drayson & Cranston sp. nov. and Cricotopus wangi Cranston & Krosch sp. nov. Using data from this study, we consider the wider utility of morphological and molecular diagnostic tools in untangling species diversity in the Chironomidae. Morphological support for distinguishing Cricotopus from Paratrichocladius Santo-Abreu in larval and pupal stages appears lacking for Australian taxa and brief notes are provided concerning this matter
Conochironomus (Diptera: Chironomidae) in Asia: New and redescribed species and vouchering issues
The presence of the Afro-Australian genus Conochironomus Freeman, 1961 (Diptera: Chironomidae) in Asia has been recognised only informally. An unpublished thesis included Conochironomus from Singapore, and the genus has been keyed from Malaysia without named species. Here, the Sumatran Conochironomus tobaterdecimus (Kikuchi & Sasa, 1980) comb. n. is recorded from Singapore and Thailand. The species is transferred from Sumatendipes Kikuchi & Sasa, 1980, rendering the latter a junior synonym (syn. n.) of Conochironomus Freeman. Conochironomus nuengthai sp. n. and Conochironomus sawngthai sp. n. are described as new to science, based on adult males from Chiang Mai, Thailand. All species conform to existing generic diagnoses for all life stages, with features from male and female genitalia, pupal cephalic tubercles and posterolateral ‘spurs’ of tergite VIII providing evidence for species distinction. Some larvae are linked to C. tobaterdecimus through molecular barcoding. Variation in other larvae, which clearly belong to Conochironomus and are common throughout Thailand, means that they cannot be segregated to species. Larval habitats include pools in river beds, urban storage reservoirs, drains with moderately high nutrient loadings, and peat swamps. Endochironomus effusus Dutta, 1994 from north-eastern India may be a congener but may differ in adult morphology, thereby precluding formal new combination until discrepancies can be reconciled. Many problems with vouchering taxonomic and molecular material are identified that need to be rectified in the future.Studies in Asia were supported by an endowment to the University of California at Davis (2000–2010) by the late
Evert Schlinger which also funded Marianne Dominguez to provide line drawings of some immature stages. The
US National Science Foundation (NSF,DEB-0531513) funded surveys in Thailand through Robert Sites
(University of Missouri). Akekawat Vitheepradit (now of Department of Entomology, Kasetsart University,
Bangkok) organised field work, permits, logistical support, collected much material and advised on names derived
from Thai. Financial support was provided by the joint PUB-NUS project entitled “Chironomid Mass Emergences
in Singapore: Monitoring Protocols and Identification of Triggers” (Grant number R-154-000-526-490) managed
by Esther Clewes and Rudolf Meier (NUS). Various permits to study midges allowed collection of Singapore and
Thai material. Bilgenur Baloğlu and Sujatha Narayanan Kutty (NUS) are thanked for provision of molecular data
and specimen registration with GenBank, and YuChen Ang (NUS) for habitus image
A new genus and species of Australian Tanypodinae (Diptera: Chironomidae) tolerant to mine waste
For over 25 years an undescribed Tanypodinae (Diptera: Chironomidae) has been known to dominate the lotic invertebrate assemblage associated with long-term polluting mine adits in Captains Flat, on the Molonglo River, southern New South Wales, Australia. Although known in all life stages, it has been impossible to allocate the species to any described genus. Renewed interest in the taxonomy of the Tanypodinae, particularly associated with molecular investigations and pollution indicator status warrants formal description. All stages conform to tribe Pentaneurini, but each life stage differs in morphological resemblance. Yarrhpelopia Cranston gen. n. is proposed for the taxon previously referred to under the informal code name of 'genus A'. The genus name derives from south-east Australian aboriginal word yarrh, in recognition of its core distribution and presence in flowing waters. A single species, A. norrisi Cranston sp. n., is described, acknowledging the late Professor Richard Norris, an influential Australian limnologist. Larvae dominate the benthos immediately adjacent to mine adits that continue to leach heavy metals (zinc, cadmium, copper and lead) into downstream sediments. A wider distribution includes cleaner near pristine, eastern Australian rivers between 30° and 42°S, but these records are excluded from the type series pending molecular insights into species limits
Improved underwater image enhancement algorithms based on partial differential equations (PDEs)
The experimental results of improved underwater image enhancement algorithms
based on partial differential equations (PDEs) are presented in this report.
This second work extends the study of previous work and incorporating several
improvements into the revised algorithm. Experiments show the evidence of the
improvements when compared to previously proposed approaches and other
conventional algorithms found in the literature.Comment: 22 pages, 6 figure
Phytophagy in a Polypedilum (Diptera: Chironomidae) species new to Australia and Japan: taxonomy and expanded Asian distribution
Polypedilum johannseni Sublette & Sublette (= Chironomus (Polypedilum) anticus Johannsen), described from
Indonesia, is recorded from Australia, where larvae are newly reported to feed on species of the aquatic fern Azolla
Lam. (Salviniaceae). We extend the Australian distribution for the species that was reported previously as
Polypedilum ‘nr seorsus’ from northern Australia. Review of the species in Asia shows previously known presence in Singapore as Polypedilum anticus and in Thailand and the Philippines, where the larva was reported to feed
on Azolla. In China, Polypedilum johannseni is reported from a diverse range of aquatic host plants, including
Azolla. We also newly report the species from Japan, where larvae feed on hybrid Azolla cristata × Azolla
filiculoides and Trapa japonica Flerow (Lythraceae). We review the taxonomy, provide new illustrations, record
and map the wider distribution and comment on morphological variation. Here, we also redescribe the Australian
Polypedilum seorsus (Skuse) with which P. johannseni has been confused, and from China, we redescribe
Polypedilum tigrinum Hashimoto, the larva of which is a proven aquatic phytophage that co-occurs with several
species of Polypedilum, including P. johannseni.The Australian Biological Resources Study (ABRS) supported
collecting in Australia in the 1980s and 90s, with concurrent support for survey of Alligator Rivers Region, Northern Territory,
by the Office of Supervising Scientist (via Chris Humphrey).
These sources provided a systematic foundation for aquatic entomological studies in remote Australia. In Singapore, collections
were made under auspices of PUB-NUS project ‘Chironomid
Mass Emergences in Singapore: Monitoring Protocols and Identification of Triggers’ (grant number R-154-000-526-490), and
we thank Yuchen Ang (Lee Kong Chian Natural History
Museum, Singapore) who kindly provided several images. In
China, collections were partially supported by the National
Natural Science Foundation of China (grant numbers 41672346
and 31100389)
Uniform shrinking and expansion under isotropic Brownian flows
We study some finite time transport properties of isotropic Brownian flows.
Under a certain nondegeneracy condition on the potential spectral measure, we
prove that uniform shrinking or expansion of balls under the flow over some
bounded time interval can happen with positive probability. We also provide a
control theorem for isotropic Brownian flows with drift. Finally, we apply the
above results to show that under the nondegeneracy condition the length of a
rectifiable curve evolving in an isotropic Brownian flow with strictly negative
top Lyapunov exponent converges to zero as with positive
probability
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