Cesar

Parkville, Australia
Parkville, Australia

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Dos Santos S.C.,Federal University of Pernambuco | Furtado F.,Federal University of Pernambuco | Lins W.,C.E.S.A.R
Proceedings - Frontiers in Education Conference, FIE | Year: 2015

In order to exploit the benefits of PBL and mitigate the risk of failure when implementing it, the NEXT (iNnovative Educational experience in Technology) research group has been working on methods and tools focused on managing the PBL approach as applied to Computing. In this context, this article proposes a teaching and learning methodology based on PBL, called xPBL, consisting of elements that reinforce PBL principles, namely: real and relevant problems; a practical environment; an innovative and flexible curriculum; an authentic assessment process; close monitoring by technical tutors and process tutors, and finally, professional practitioners as teachers and tutors. Based on these elements, the paper describes the design of a PBL approach for a Design course, grounded on acquired knowledge of Design content and past PBL experiences in Software Engineering courses. This approach provides an insightful guide to implementing PBL from xPBL methodology, and provides instruments based on management techniques such as 5W2H (what, why, who, when, where, how and how much) and the production of artifacts to support the conception process of courses based on PBL. © 2014 IEEE.


Furlan E.M.,University of Melbourne | Griffiths J.,Cesar | Griffiths J.,Australian Department of Primary Industries and Fisheries | Gust N.,Biofouling Solutions | And 4 more authors.
Conservation Genetics | Year: 2013

Dispersal patterns can have a major impact on the dynamics and viability of populations, and understanding these patterns is crucial to the conservation and management of a species. In this study, patterns of sex-biased dispersal and waterway/overland dispersal are investigated in the endemic Australian platypus, Ornithorhynchus anatinus, a semi-aquatic monotreme. Analyses of over 750 individuals from south-eastern Australia at 13 microsatellite loci and two mitochondrial genes, cytochrome b and cytochrome oxidase subunit II, provide genetic insight into dispersal patterns. For the first time, platypuses of western Victoria are shown to be genetically distinct from other populations of the mainland. Despite distinct morphological differentiation either side of the Great Dividing Range, populations remain genetically similar between coastal and inland areas suggesting gene flow is likely to occur across these ranges. Landscape genetic analyses indicate variability in dispersal patterns between Victorian and Tasmanian platypuses with a greater avoidance of overland travel indicated in Victoria compared to Tasmania. Females appear to remain within their natal area or return to breed, maintaining greater genetic structure in maternally inherited mitochondrial DNA in comparison to nuclear DNA and sharing genetic similarity within a short river distance (i.e. ≤1.4 km). The results of this study provide a valuable spatial framework for the management of wild platypus populations within south-eastern Australia and a baseline for future monitoring of populations that are likely to be impacted by environmental and anthropogenic change. © 2013 Springer Science+Business Media Dordrecht.


Jenkins S.,University of Melbourne | Hoffmann A.A.,University of Melbourne | McColl S.,CESAR | Tsitsilas A.,University of Melbourne | Umina P.A.,University of Melbourne
Journal of Economic Entomology | Year: 2013

Broad-spectrum pesticides used to protect field crops and pastures from invertebrate pests are frequently reported to reduce populations of nontarget fauna, but there is often little relevant field data. Nonetheless, this notion is used to promote the adoption of more selective pesticides with less impact on nontarget invertebrates, including beneficial insects. Selective pesticides are not widely available for broad-acre grain crops and pastures in southern Australia; however, several options available in other industries could be compatible with these agricultural systems. In this study, the impact of broad-spectrum pesticides and several selective pesticides on nontarget invertebrate fauna was assessed in five field trials in wheat and canola fields. Despite extensive sampling over short and medium timeframes, few treatment effects on nontarget groups were detected. In cases where broad-spectrum pesticides were detrimental, patterns were often inconsistent among nontarget groups and between field trials. In contrast, the pest species, Hatotydeus destructor Tucker and Penthateus spp., were effectively controlled by the broad-spectrum treatments and less effectively by the selective pesticides. The inconsistent and relatively small impact of broad-spectrum pesticides on some nontarget invertebrates demonstrates that caution is required when extrapolating from laboratory-based assessments routinely used to assess the impacts of pesticides to field conditions in agriculture. © 2013 Entomological Society of America.


Roberts J.M.K.,University of Melbourne | Roberts J.M.K.,CSIRO | Weeks A.R.,University of Melbourne | Hoffmann A.A.,University of Melbourne | And 2 more authors.
Biological Control | Year: 2011

Throughout southern Australia, the lucerne flea, Sminthurus viridis (Collembola: Sminthuridae), is an important pest of a variety of winter grain crops and pastures. The predatory mite, Bdellodes lapidaria (Acari: Bdellidae), co-occurs with S. viridis and is reported to be a biological control agent of this pest. Using laboratory bioassays and field experiments, we assessed the susceptibility of B. lapidaria to several pesticides and investigated its impact in controlling S. viridis. In the laboratory, B. lapidaria was found to be susceptible to the synthetic pyrethroids, α-cypermethrin and bifenthrin, but relatively tolerant to the avermectin, abamectin, and organophosphorous chemicals, omethoate and chlorpyrifos. In field experiments, B. lapidaria was not adversely affected by applications of either bifenthrin or omethoate. Despite strong intraspecific interactions, we found no detectable impact of B. lapidaria on S. viridis numbers in the field. These results indicate that B. lapidaria has a relatively high tolerance to several pesticides, perhaps partly through behavioural avoidance, but little impact as a biological control agent on S. viridis in south-eastern Australia. © 2011 Elsevier Inc.


Umina P.A.,University of Melbourne | Weeks A.R.,Cesar | Weeks A.R.,University of Melbourne | Roberts J.,University of Melbourne | And 4 more authors.
Pest Management Science | Year: 2012

Background: The redlegged earth mite, Halotydeus destructor Tucker, is an important pest of broad-acre farming systems in Australia, New Zealand and South Africa. In 2006, high levels of resistance to synthetic pyrethroids were discovered in this species in Western Australia. Results: Between 2007 and 2010, the authors monitored resistance in field populations and found it had spread considerably within the state of Western Australia. Twenty-six paddocks from 15 individual properties were identified with resistance, and these paddocks ranged over 480 km. To date, resistance has not been detected in any other Australian state. Resistance in H. destructor appears to be found across the entire pyrethroid group, but not to other chemical classes such as organophosphates and carbamates, or other chemistries with novel modes of action. Conclusion: The high levels of resistance occurring in Western Australia have caused considerable economic losses due to ineffective chemical applications and mortality of crop plants at seedling establishment. These findings highlight the need for a comprehensive resistance surveillance programme to be developed for H. destructor within Australia. Growers need to consider non-chemical approaches for pest control and should be encouraged to implement pesticide resistance management programmes for H. destructor. © 2011 Society of Chemical Industry.


Miller A.D.,Cesar | Miller A.D.,University of Melbourne | Good R.T.,University of Melbourne | Coleman R.A.,University of Melbourne | And 4 more authors.
Molecular Biology Reports | Year: 2013

A suite of polymorphic microsatellite markers and the complete mitochondrial genome sequence was developed by next generation sequencing (NGS) for the critically endangered orange-bellied parrot, Neophema chrysogaster. A total of 14 polymorphic loci were identified and characterized using DNA extractions representing 40 individuals from Melaleuca, Tasmania, sampled in 2002. We observed moderate genetic variation across most loci (mean number of alleles per locus=2.79; mean expected heterozygosity=0.53) with no evidence of individual loci deviating significantly from Hardy-Weinberg equilibrium. Marker independence was confirmed with tests for linkage disequilibrium, and analyses indicated no evidence of null alleles across loci. De novo and reference-based genome assemblies performed using MIRA were used to assemble the N. chrysogaster mitochondrial genome sequence with mean coverage of 116-fold (range 89 to 142-fold). The mitochondrial genome consists of 18,034 base pairs, and a typical metazoan mitochondrial gene content consisting of 13 protein-coding genes, 2 ribosomal subunit genes, 22 transfer RNAs, and a single large non-coding region (control region). The arrangement of mitochondrial genes is also typical of Avian taxa. The annotation of the mitochondrial genome and the characterization of 14 microsatellite markers provide a valuable resource for future genetic monitoring of wild and captive N. chrysogaster populations. As found previously, NGS provides a rapid, low cost and reliable method for polymorphic nuclear genetic marker development and determining complete mitochondrial genome sequences when only a fraction of a genome is sequenced. © 2012 Springer Science+Business Media Dordrecht.


Clouston A.,Cesar | Edwards O.,SIRO Land and Water Flagship | Umina P.,Cesar | Umina P.,University of Melbourne
Crop and Pasture Science | Year: 2016

Brevicoryne brassicae (Linnaeus), Lipaphis pseudobrassicae (Davis), Acyrthosiphon kondoi (Shinji), Aphis craccivora (Koch) and Rhopalosiphum padi (Linnaeus) are among the most important aphid pests in Australian broadacre systems. In this study a leaf-dip method was used to assay pirimicarb, dimethoate, α-cypermethrin and imidacloprid against field populations collected from Victoria, New South Wales, South Australia, Western Australia and Queensland. This research established toxicity baseline data that will be important for future monitoring of insecticide responses in broadacre crops. It also provided an opportunity to identify any chemical tolerance that may be evolving in these pests. Acyrthosiphon craccivora populations showed differences in their responses to dimethoate, pirimicarb and imidacloprid (but not to a-cypermethrin), indicating possible shifts in field sensitivity to these three chemicals. Rhopalosiphum padi had the lowest sensitivity to all insecticides tested, with two populations (collected from South Australia and Queensland) showing less than 100% mortality when tested at the field rate of α-cypermethrin. There were few differences in insecticide responses between populations of the other three species. Continued screening of A. craccivora and R. padi populations is needed to fully assess the current status of tolerance among field populations and to strengthen resistance management tactics. © CSIRO 2016.


Griffiths J.,Cesar | Kelly T.,Cesar | Weeks A.,Cesar | Weeks A.,University of Melbourne
Australian Mammalogy | Year: 2013

It has been suggested that platypuses (Ornithorhynchus anatinus) may avoid nets following capture, compromising abundance estimates using mark-recapture models. Here, we present the first direct evidence of net avoidance behaviour by the platypus. Using acoustic telemetry, we record a platypus bypassing several nets following capture. Understanding variation in capture probabilities will lead to better estimation of platypus abundance, which is currently lacking. © 2013 Australian Mammal Society.


Furlan E.,University of Melbourne | Stoklosa J.,University of Melbourne | Griffiths J.,CESAR | Griffiths J.,Australian Department of Primary Industries and Fisheries | And 4 more authors.
Ecology and Evolution | Year: 2012

Genetic diversity generally underpins population resilience and persistence. Reductions in population size and absence of gene flow can lead to reductions in genetic diversity, reproductive fitness, and a limited ability to adapt to environmental change increasing the risk of extinction. Island populations are typically small and isolated, and as a result, inbreeding and reduced genetic diversity elevate their extinction risk. Two island populations of the platypus, Ornithorhynchus anatinus, exist; a naturally occurring population on King Island in Bass Strait and a recently introduced population on Kangaroo Island off the coast of South Australia. Here we assessed the genetic diversity within these two island populations and contrasted these patterns with genetic diversity estimates in areas from which the populations are likely to have been founded. On Kangaroo Island, we also modeled live capture data to determine estimates of population size. Levels of genetic diversity in King Island platypuses are perilously low, with eight of 13 microsatellite loci fixed, likely reflecting their small population size and prolonged isolation. Estimates of heterozygosity detected by microsatellites (HE =0.032) are among the lowest level of genetic diversity recorded by thismethod in a naturally outbreeding vertebrate population. In contrast, estimates of genetic diversity on Kangaroo Island are somewhat higher. However, estimates of small population size and the limited founders combined with genetic isolation are likely to lead to further losses of genetic diversity through time for the Kangaroo Island platypus population. Implications for the future of these and similarly isolated or genetically depauperate populations are discussed. © 2012 The Authors.


PubMed | Cesar, Deakin University and University of Melbourne
Type: Journal Article | Journal: Molecular ecology | Year: 2016

Estimating contemporary genetic structure and population connectivity in marine species is challenging, often compromised by genetic markers that lack adequate sensitivity, and unstructured sampling regimes. We show how these limitations can be overcome via the integration of modern genotyping methods and sampling designs guided by LiDAR and SONAR data sets. Here we explore patterns of gene flow and local genetic structure in a commercially harvested abalone species (Haliotis rubra) from southeastern Australia, where the viability of fishing stocks is believed to be dictated by recruitment from local sources. Using a panel of microsatellite and genomewide SNP markers, we compare allele frequencies across a replicated hierarchical sampling area guided by bathymetric LiDAR imagery. Results indicate high levels of gene flow and no significant genetic structure within or between benthic reef habitats across 1400km of coastline. These findings differ to those reported for other regions of the fishery indicating that larval supply is likely to be spatially variable, with implications for management and long-term recovery from stock depletion. The study highlights the utility of suitably designed genetic markers and spatially informed sampling strategies for gaining insights into recruitment patterns in benthic marine species, assisting in conservation planning and sustainable management of fisheries.

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