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1

Zenger, Kyall Richard. "Genetic linkage maps and population genetics of macropods". Phd thesis, Australia : Macquarie University, 2002. http://hdl.handle.net/1959.14/47604.

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"November 2001".
Thesis (PhD)--Macquarie University, Division of Environmental and Life Sciences, Department of Biological Sciences, 2002.
Bibliography: leaves 136-157.
General introduction -- Molecular markers for comparative and quantitative studies in macropods -- Genetic linkage map construction in the tammar wallaby (M. eugenii) -- Intraspecific variation, sex-biased dispersal and phylogeography of the eastern grey kangaroo (M. giganteus) -- General discussion.
The analysis of DNA using molecular techniques is an important tool for studies of evolutionary relationships, population genetics and genome organisation. The use of molecular markers within marsupials is primarily limited by their availability and success of amplification. Within this study, 77 macropodid type II microsatellite loci and two type I genetic markers were characterised within M. eugenii to evaluate polymorphic levels and cross-species amplification artifacts. Results indicated that 65 microsatellite loci amplified a single locus in M. eugenii with 44 exhibiting high levels of variability. The success of crossspecies amplification of microsatellite loci was inversely proportional to the evolutionary distance between the macropod species. It is revealed that the majority of species within the Macropodidae are capable of using many of the available heterologous microsatellites. When comparing the degree of variability between source-species and M. eugenii, most were significantly higher within source species (P < 0.05). These differences were most likely caused by ascertainment bias in microsatellite selection for both length and purity. -- The production of a marsupial genetic linkage map is perhaps one of the most important objectives in marsupial research. This study used a total of 353 informative meioses and 64 genetic markers to construct a framework genetic linkage map for M. eugenii. Nearly all markers (93.7%) formed a significant linkage (LOD > 3.0) with at least one other marker. More than 70% (828 cM) of the genome had been mapped when compared with chiasmata data. Nine linkage groups were identified, with all but one (LG7; X-linked) allocated to the autosomes. Theses groups ranged in size from 15.7 cM to 176.5 cM, and have an average distance of 16.2 cM between adjacent markers. Of the autosomal linkage groups, LG2 and LG3 were assigned to chromosome 1 and LG4 localised to chromosome 3 based on physical localisation of genes. Significant sex-specific distortions towards reduced female recombination rates were revealed in 22% of comparisons. Positive interference was observed within all the linkage groups analysed. When comparing the X-chromosome data to closely related species it is apparent that it is conserved both in synteny and gene order. -- The investigation of population dynamics of eastern grey kangaroos has been limited to a few ecological studies. The present investigation provides analysis of mtDNA and microsatellite data to infer both historical and contemporary patterns of population structuring and dispersal. The average level of genetic variation across sample locations was exceedingly high (h = 0.95, HE = 0.82), and is one of the highest observed for marsupials. Contrary to ecological studies, both genic and genotypic analyses reveal weak genetic structure of populations where high levels of dispersal may be inferred up to 230 km. The movement of individuals was predominantly male-biased (average N,m = 22.61, average N p = 2.73). However, neither sex showed significant isolation by distance. On a continental scale, there was strong genetic differentiation and phylogeographic distinction between southern (TAS, VIC and NSW) and northern (QLD) Australian populations, indicating a current and / or historical restriction of geneflow. In addition, it is evident that northern populations are historically more recent, and were derived from a small number of southern eastern grey kangaroo founders. Phylogenetic comparisons between M. g. giganteus and M. g. tasmaniensis, indicated that the current taxonomic status of these subspecies should be revised as there was a lack of genetic differentiation between the populations sampled.
Mode of access: World Wide Web.
xv, 182 leaves ill
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2

Haouchar, Dalal. "Using ancient DNA to investigate extinction, extirpation and past biodiversity of Australian macropods". Thesis, Haouchar, Dalal (2016) Using ancient DNA to investigate extinction, extirpation and past biodiversity of Australian macropods. PhD thesis, Murdoch University, 2016. https://researchrepository.murdoch.edu.au/id/eprint/32550/.

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The field of ancient DNA (aDNA) involves the isolation and retrieval of trace amounts of degraded DNA from a variety of substrates including fossils, sediments and historical material. The fragmentary nature of aDNA necessitates the use of methods with the ability to capture and amplify short segments of DNA. Collectively aDNA studies have made significant and unique contributions to a wide field of research including conservation, population genetics, taxonomy and phylogeny. The primary aim of this thesis research is to explore the utility of aDNA techniques to study extirpation, extinction and past biodiversity of Australian macropods. Using a combination of historical, Holocene and Pleistocene aged fossils, this research will attempt to investigate what ancient mitochondrial DNA (mtDNA) can add to our knowledge of Australia’s macropods. Traditional aDNA techniques have largely been used to isolate mtDNA from single fossil samples - an example of this approach is shown in Chapter Two where a wellpreserved wallaby fossil bone from Depuch Island (Western Australia) was studied. The ancient mtDNA (cytochrome b and control region) data produced strong phylogenetic signal and shows that the Depuch Island rock-wallaby specimen is most similar to the mainland Petrogale lateralis lateralis. This finding has conservation implications for ongoing rehabilitation and translocation efforts in the Pilbara region. Chapter Three of this thesis also uses mitochondrial aDNA techniques, to explore questions regarding interrelationships and former distribution of a macropod species complex; Bettongia spp. Cytochrome b and control region data retrieved from 88 historical samples, along with ~214 already sequenced samples, place the most recent common ancestor of the brush-tailed bettongs at c. 2.5 Myr. Ancient mtDNA is suggestive of connectivity between what are now highly fragmented populations, a result that has implications for how critically endangered brush-tailed bettongs should be managed. Ancient DNA analyses and DNA sequencing technology have evolved over recent years and during the course of this study. Therefore in keeping up with the latest high-throughput sequencing (HTS) technology, aDNA analyses in ~70 bones and 20 sediment samples excavated from a Late Pleistocene–Holocene cave deposit on Kangaroo Island, South Australia was undertaken. Samples were selected from 15 stratigraphic layers, ranging in age from >20 ka to ~6.8 ka. The successful retrieval of bona fide aDNA sequences, back to at least 20 ka, demonstrates excellent longterm DNA preservation at the site. All unidentified bones that were screened revealed a number of taxa from the assemblage including, Macropus, Onychogalea, Potorous, Bettongia, Dasyurus, Rattus and Notechis. The results from this study add significant value to the late Pleistocene-mid-Holocene paleontological record, detailing the past diversity of flora and fauna on Kangaroo Island. Lastly, Chapter 5 introduces the latest molecular techniques in capturing and enriching highly fragmented aDNA bone from four sites across Australia. Ancient DNA extractions techniques, targeting ultra-short DNA fragments, were employed in an attempt to obtain Pleistocene-aged material. The warm conditions, a factor common in Australian caves, are not conductive to long-term DNA preservation at many sites. Shotgun sequencing was only successful on six bone samples (including one incisor) from a total of 25 samples that were screened. Three samples were successfully captured and enriched for endogenous DNA; one bettong sample generated 89.6% of a mtDNA genome with 5.4X coverage. Overall, the decay rate of DNA and preservation across all four sites was high, and extremely degraded, with an average fragment length between 47 bp and 57 bp. These data demonstrate that recovery of Pleistocene-aged aDNA from warm climate sites across Australia will remain a challenge and that better ways to screen and predict DNA survival are needed. This thesis presents a combination of work from multiple sites across Australia using a range of aDNA techniques and sequencing technologies that have evolved over the tenure of this thesis. Collectively, this body of work has demonstrated the value of integrating aDNA data into modern-day conservation decision-making and has contributed to a wider understanding of Australian macropods both past and present.
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3

Fukuda, Yuki. "The effects of closing watering points on populations of large macropods and landscape rehabilitation in a semi-arid national park /". [St. Lucia, Qld.], 2006. http://adt.library.uq.edu.au/public/adt-QU20060511.125915/index.html.

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4

Rendle, Jessica Amy Jane. "Epidemiology of lumpy jaw in captive macropods across Australia and Europe: An investigation of disease risk and treatment approaches". Thesis, Rendle, Jessica Amy Jane (2019) Epidemiology of lumpy jaw in captive macropods across Australia and Europe: An investigation of disease risk and treatment approaches. PhD thesis, Murdoch University, 2019. https://researchrepository.murdoch.edu.au/id/eprint/49721/.

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Lumpy jaw is a well-recognised cause of morbidity and mortality in captive macropods (Macropodidae) worldwide. The extent and causes of the disease are largely unknown, although multiple risk factors associated with a captive environment are thought to contribute to the development of clinical disease. Identification of risk factors associated with lumpy jaw would assist with the development of preventive management strategies, potentially reducing mortalities. A cross-sectional study was undertaken from 2011 to 2015, to determine prevalence and risk factors for this disease through the distribution of a survey to 527 institutions across Australia and Europe; two regions where macropods are popular exhibits. Veterinary and husbandry records from the period 1st January 1995 up to and including 28th November 2016 (the last date when data were extracted from zoo records) were analysed in a retrospective cohort study, examining risk factors for developing disease and treatments used, over time. Computed tomography was used to examine disease occurrence in wild macropods using skulls from population management culls. The prevalence of lumpy jaw was found to differ between the two regions (p < 0.0002). A review of 6178 records for 2759 macropods housed within eight zoos across the Australian and European regions, found incidence rates and risk of infection differed between geographic regions and individual institutions. Risk of developing lumpy jaw increased with age, particularly for macropods >10 years (Australia IRR 7.63, p < 0.001; Europe IRR 7.38, p < 0.001). Treatment approach varied and prognosis was typically poor with 62.5% mortality for Australian and European regions combined. Lumpy jaw was detected in all captive genera examined, but was absent from the wild populations studied. Geographic region influenced the incidence of lumpy jaw, the risks associated with developing clinical disease, and preferred treatment approach. Despite advances in antibiotic therapy and surgical techniques, treatment of lumpy jaw is largely unrewarding for the individual and should be approached on an individual basis. This research provides new information about this refractory disease and makes practical recommendations to reduce disease risk. This information may assist institutions in providing optimal long-term health management for captive macropods; such efforts having a positive impact on both welfare and conservation, including but not limited to captive breeding and translocation programs.
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5

Rombang, Johan Alexander. "An investigation into subsurface macropore flow using an artificial macropose system". Thesis, University of Reading, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.336690.

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6

Blacker, Amy Rachael. "Wallabies and Roads: Interactions and Management in an Urbanising Landscape". Thesis, Griffith University, 2014. http://hdl.handle.net/10072/367128.

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Understanding the impacts of roads on wildlife and the natural environment is of increasing importance, especially in the context of widespread urbanisation. Macropods (mostly kangaroos and wallabies) are a diverse and widespread taxon in Australia that has been significantly affected by the presence of roads in various ways. Although a moderate volume of research has been conducted on the interactions between macropod species and roads in Australia, this a fraction of the research effort conducted on large mammals in Europe and North America. Research that encompasses a variety of aspects of interactions between roads and macropods (and wildlife in general) is needed to broaden our perspective on impacts and mitigation. Patterns of wallaby road mortality were investigated in a per-urban area of South East Queensland. Wallaby road-kill rates varied greatly; between 0.044 and 0.883 road-kills km-1 month-1 at the road or road section scale. Four wallaby mortality hotspots and several other areas of high mortality density were identified from the kernel density spatial analysis. Percent of commercial vehicle traffic (positively correlated) and distance to water (negatively correlated) were important spatial variables for determining the patterns of red-necked wallaby road-kill. Cumulative rainfall over the previous four weeks and maximum wind gust speed (both negatively correlated) were important temporal variables in determining the patterns of red-necked wallaby road-kill. Too few swamp wallaby road-kills were observed to be analysed.
Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
Griffith School of Environment
Science, Environment, Engineering and Technology
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7

Batany, Stéphane. "Influence d’un macropore sur l’écoulement et le transport de solutés en milieu poreux : expérimentations sur sol modèle macroporé et simulations numériques". Thesis, Paris Est, 2016. http://www.theses.fr/2016PESC1085/document.

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La modélisation des écoulements et du transport dans les milieux poreux est un domaine actif pour, notamment, progresser dans la compréhension du transfert des polluants dans les sols. Les sols présentent fréquemment des hétérogénéités comme des macropores (provoqués par la faune, la flore ou des fissures) et un certain nombre de modèles numériques utilisent les concepts de double ou de multi-perméabilité pour tenir compte de tous les types d’écoulements susceptibles de coexister dans de tels systèmes. Cependant, les modèles classiques semblent sous-estimer l’effet de la macroporosité sur l’écoulement et le transfert préférentiels et restreindre la zone d’écoulement préférentiel au seul volume occupé par la macroporosité. Diverses études expérimentales antérieures à cette thèse ont questionné cette hypothèse. Cette étude se propose de comprendre l’établissement de l’écoulement et du transport préférentiel et en particulier les mécanismes d’échange d’eau et de masse entre un macropore et une matrice poreuse environnante en condition saturée. Pour cela, des traçages de l’eau sont réalisés pour un milieu poreux modèle constitué de billes de verre, traversé par un macropore synthétique et mis en place en colonnes de laboratoire. Elution et transfert dans les colonnes sont caractérisés par suivi de la concentration en sortie et par imagerie par résonance magnétique. Un modèle numérique développé sur la base de la méthode de Boltzmann sur réseau est utilisé pour simuler numériquement des écoulements dans un système macroporé et identifier les mécanismes d’écoulements préférentiels à l’échelle de pores. Les données expérimentales montrent que le transfert du traceur est fortement dépendant du débit d’injection ainsi que du coefficient de diffusion dans l’eau. À fort débit, le transfert semble s’effectuer exclusivement dans le macropore, avec très peu d’échange avec la matrice. Pour des débits plus faibles, la percée présente une inflexion suivie d’un pic. Les images IRM montrent alors un échange significatif de traceur entre le macropore et la matrice poreuse environnante. Les simulations numériques sont utilisées pour calculer le champ de vitesse de l’écoulement dans le système en fonction du débit. Les modélisations numériques montrent que l’écoulement préférentiel est étendu dans la matrice poreuse sur une zone de même dimension que le diamètre moyen des grains indépendamment de la taille du macropore et du débit, dans la gamme de débits simulés. Ces résultats expérimentaux et numériques montrent que l’influence du macropore sur les transferts doit être étendue dans la matrice poreuse sur une zone de la taille des grains pour l’écoulement et sur une zone dépendant du coefficient de diffusion du traceur ainsi que du temps de séjour moyen de celui-ci pour le transfert des solutés
Flow and transport modeling through porous media is of primary concern nowadays, especially in order to progress in the understanding of pollutant transfers through soils. Soils present frequently heterogeneities such as macropores (caused by fauna, flora or cracks) and several numerical models use double or multi permeability concepts in order to take into account all flow types that may exist in such porous systems. Nevertheless, classical models seem underestimate the macropore effect on preferential flow and transport by restricting the preferential flow zone only to the volume occupied by the macroporosity. Various experimental studies prior to this thesis have questioned this hypothesis. This study proposes to understand the establishment of preferential flow and transport and in particular the mechanism of flow and solute exchanges between a synthetic macropore and a surrounding porous matrix in saturated condition. For this purpose, water tracing are realized for a model porous media constituted by glass beads, crossed by a synthetic macropore and implemented in laboratory columns. Breakthrough and transport in columns are characterized by monitoring the concentration at the end of the column by magnetic nuclear resonance. A numerical model developed on the basis of lattice-Boltzmann method is used to simul ate flow in macroporous system and identify preferential flow mechanisms at pore scale. Experimental data show that tracer transport is strongly dependent on injection flow rate and the diffusion coefficient in water. At high flow rate, the transport seems to occur exclusively in the macropore, with very little masse exchange with the porous matrix. At lower flow rates, the breakthrough exhibits an inflexion followed by a peak. The MRI images show a significant mass exchange of tracer between the macropore and the surrounding porous matrix. The numerical simulations are used to calculate the flow field in a porous system as a function of flow rate. They show that preferential flow is extended in porous matrix into a zone of same dimension the mean diameter of beads regardless of macropore size or injected flow rate, in the range of simulated flow rates. These experimental and numerical results show that macropore influence on transport should be extended through the surrounding porous matrix into a zone of the same size of grains diameter for flow and into a zone depending on diffusion coefficient as well as mean residence time of the studied tracer for solute transport
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8

Askar, Azza. "Macropore drainage of unsaturated swelling soil". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/tape17/PQDD_0028/MQ35826.pdf.

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9

Kramadibrata, Padmi. "A revision of the genus Calamus (Palmae) section Macropodus sensu Furtado". Thesis, University of Reading, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.317720.

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10

Asperger, Michael. "Zur Ätiologie und Bekämpfung der Lumpy Jaw Disease bei Kängurus". Doctoral thesis, Universitätsbibliothek Leipzig, 2004. http://nbn-resolving.de/urn:nbn:de:bsz:15-qucosa-37575.

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In der vorliegenden Arbeit sollten die in der veterinärmedizinischen Literatur bisher diskutierten Ursachen für LJD bei Makropoden hinsichtlich ihrer tatsächlichen Bedeutung abgeklärt und die Eignung einer formalininaktivierten, bestandsspezifischen Adsorbatvakzine zur Prophylaxe von LJD getestet werden. Da LJD eine parodontale Erkrankung darstellt, wurden auch die für Entstehung einer humanen Parodontitis prädisponierenden Faktoren mit in die Untersuchung einbezogen. Es wurden Tupferproben zur bakteriologischen Untersuchung von insgesamt 15 gesunden und 11 an LJD erkrankten Kängurus entnommen. Dabei konnten gramnegative Anaerobier bei allen Tieren isoliert werden. Fusobacterium nucleatum wurde in 82% der von an LJD erkrankten und nur in 33% der von gesunden Tieren entnommenen Tupferproben nachgewiesen, womit sich ein signifikanter Zusammenhang (P < 0,05) zwischen diesem Erreger und LJD ergab. Weitere überwiegend bei erkrankten Makropoden nachgewiesene Anaerobier stellten Prevotella oris/oralis (bei 73% der LJD-Fälle und bei 40% der gesunden Tiere) sowie Capnocytophaga spp. (45% vs. 13%) dar. Bacteroides spp. und Porphyromonas gingivalis wurden – wenn auch nur mit 3 bzw. 2 Nachweisen – ausschließlich bei kranken Tieren isoliert. Fusobacterium necrophorum wurde jeweils in 27% der Kängurus gefunden und spielte damit in dieser Studie keine Rolle für die Entstehung von LJD. In Übereinstimmung mit der Literatur konnten Moraxella spp. ausschließlich bei gesunden Makropoden isoliert werden. Vertreter dieser Gattung gehören damit offensichtlich zur normalen Maulflora der Kängurus. Für die Zoos in Halle und Leipzig wurde eine formalininaktivierte, bestandsspezifische Adsorbatvakzine gegen die bei einem an LJD erkrankten Känguru des jeweiligen Bestandes isolierten gramnegativen Anaerobier hergestellt. 7 Tiere (2 Rote Riesenkängurus, 5 Bennettwallabies) des Leipziger Zoos und 6 Bennettkängurus des Zoos in Halle wurden geimpft, wobei Auffrischungsimpfungen nach 4 bzw. 8 Wochen und nach 6 bzw. 12 Monaten erfolgten. Die spezifischen AK gegen das Prüfantigen Fusobacterium necrophorum wurden im SLA bestimmt. Es konnte keine Erhöhung der AK-Titer induziert werden und auch die Todesrate infolge von LJD senkte sich während des Untersuchungszeitraumes von 42 Monaten in den beiden Zoos nicht. Die höchsten AK-Level (1:512 bis 1:2048) ließen sich im Serum von natürlich infizierten und letztendlich tödlich erkrankten Bennettwallabies des Zoos in Hoyerswerda feststellen. Der Nachweis von AK-Titern im Serum von nicht geimpften Jungtieren lässt vermuten, dass AK via Kolostrum oder Dottersackplazenta auf die Jungtiere übertragen werden. Die Untersuchungen hinsichtlich der Fütterung zeigten, dass im Zoo Leipzig eine azidotische Stoffwechsellage induziert wurde, was sich bei den Leipziger Bennettkängurus in einem mit 7,53 signifikant niedrigeren Vormagen-pH-Wert im Vergleich zu den Hallenser und Auer Tieren (8,25 und 8,38) offenbarte. Dies schlug sich auch in erhöhten K-, Cholesterol- und -Amylasewerten im Serum der Leipziger Wallabies nieder, womit gezeigt werden konnte, dass sich diese Parameter offenbar auch bei Makropoden zur Diagnostik einer chronischen Azidose eignen. Die Versorgung der Bennettkängurus in Magdeburg und Halle mit Ca und P war zwar nicht ausreichend, spiegelte sich aber nicht in veränderten Blutwerten dieser Mengenelemente wider. Die Aktivität der AP nimmt mit zunehmenden Alter ähnlich wie bei anderen Tierarten ab. Ihre negative Korrelation mit dem Alter der Tiere war dabei hochsignifikant (P < 0,001, r = 0,77 bzw. 0,62). Beim direkten Vergleich gesunder mit an LJD erkrankten Tieren konnte weder eine Störung im Ca/P-Stoffwechsel noch eine Azidose in Verbindung zu LJD gebracht werden. In allen Zoos erfolgte eine Überversorgung mit Vitamin A, wobei die Bedarfswerte für Schaflämmer um das 3,5fache bis 41fache übertroffen wurden. Den Bedarfswerten am nächsten lagen die Versorgungswerte der Bennettkängurus vom TP Aue und der Östlichen Grauen Riesenkängurus vom Zoo Magdeburg, beides Bestände ohne LJD. Die ermittelten Retinolplasmakonzentrationen standen in keiner Beziehung zu den Vitamin-A-Gehalten im Futter, was darauf hindeutet, dass sich Retinolbestimmungen im Blutplasma ebenso wie bei anderen Tierarten nur in extremsten defizitären Situationen zur Einschätzung des Vitamin-A-Status eignen. Ob eine Hypervitaminose A für die Entstehung von LJD tatsächlich eine Rolle spielt, muss in zukünftigen Arbeiten unter Einbeziehung von Retinolesterbestimmungen in der Leber abgeklärt werden. Die Glukosewerte lagen mit 8,57 mmol/l (M. rufus) bzw. 6,51 mmol/l (M. rufogriseus) über den bisher bekannten Werten aus der Literatur. Da die Werte bei an LJD erkrankten Kängurus niedriger waren als bei gesunden Tieren, kann ein Diabetes mellitus als Ursache für LJD ausgeschlossen werden. Weder die Durchsicht von 144 Sektionsprotokollen noch die Bestimmung der Kreatinin- und Harnstoffkonzentration im Serum von an LJD erkrankten Tieren ließen einen Zusammenhang zwischen Erkrankungen der Nieren und LJD erkennen. 30 Tiere verendeten an LJD, wovon 20% auch an den Nieren erkrankt waren. Allerdings wiesen auch 16,7% der anderweitig gestorbenen Kängurus eine Nierenerkrankung auf. Die Serumkonzentrationen von Harnstoff bzw. Kreatinin der an LJD erkrankten Makropoden unterschieden sich nicht von den für die gesunden Roten Riesenkängurus (7,40 mmol bzw. 114 mmol/l) und Bennettwallabies (7,81 mmol/l bzw. 86 mmol/l) ermittelten Werten. Insgesamt 184 Sera von 107 Kängurus wurden auf AK gegen MaHV-1 und MaHV-2 mittels Neutralisationtest geprüft. Während 94,4% bzw. 97,2% der Roten Riesenkängurus serologisch positiv für MaHV-1 bzw. MaHV-2 waren, reagierten von den 71 überprüften Bennettkängurus nur 4 bzw. 3 Tiere positiv. Unter den Wallabies befanden sich auch 21 an LJD erkrankte Tiere, wovon lediglich 2 Tiere gegen MaHV-1 und 1 Tier gegen MaHV-2 eine Serokonversion zeigten. Die AK-Titer der Roten Riesenkängurus ließen keine Unterschiede zwischen gesunden und an LJD leidenden Tieren zu und die entnommenen Serumpaarproben von 5 zum Zeitpunkt der Blutentnahme an LJD leidenden Riesenkängurus zeigten kein einheitliches Verhalten im Sinne einer Serokonversion. Somit ließ sich der Verdacht, dass die Reaktivierung latenter Herpesinfektionen die Ursache für LJD sein könnte, nicht bestätigen. Im Ergebnis der vorliegenden Studie und im Zusammenhang mit den Angaben aus der Literatur stellt sich LJD primär als eine Infektion mit gramnegativen Anaerobiern dar, wovon Fusobacterium nucleatum, Bacteroides spp., Prophyromonas gingivalis und Fusobacterium necrophorum, Biovar A die größte Bedeutung haben dürften. Den Abschluss der Arbeit bilden Empfehlungen für die Haltung von Kängurus in zoologischen Einrichtungen und für die Therapie von LJD. Im Anhang finden sich Röntgenaufnahmen und Photographien von erkrankten und gesunden Makropoden
The aim of this thesis was the investigation of the aetiology of Lumpy Jaw Disease (LJD) in macropods concentrating specifically on the causes of the diseases in current veterinary medicine literature and to evaluate the use of a group-specific Al(OH)3-adjuvanted, formalin-inactivated whole-cell vaccine for the control of LJD in kangaroos kept in zoos. LJD is regarded as periodontal disease, therefore the risk factors for the development of human periodontitis were also included in this study. The oral flora from 15 healthy macropods and 11 animals suffering from LJD was isolated. At least one anaerobic gram-negative bacterial species was found in swabs of each macropod. The occurrence of Fusobacterium nucleatum was associated with LJD (P < 0.05) by detecting this bacterium in 82% of the kangaroos suffering from LJD compared to only in 33% of the healthy animals. Prevotella oris/oralis and Capnocytophaga spp. were also predominantly found in diseased animals in comparison with healthy macropods (73% vs. 40% and 45% vs. 13% respectively). Bacteroides spp. and Porphyromonas gingivalis were isolated in only 3 and 2 kangaroos suffering from LJD, respectively. Contrary to previously published studies about LJD Fusobacterium necrophorum was not associated with LJD, as this anaerobe was detected in only 27% of the diseased as well as healthy macropods. Moraxella spp. seem to be a part of the normal oral flora of macropods and was found exclusively in healthy animals. 11 Red-necked Wallabies (Macropus rufogriseus) and 2 Red Kangaroos (Macropus rufus) were immunized with a group-specific Al(OH)3-adjuvanted, formalin-inactivated whole-cell vaccine containing previously in a kangaroo suffering from LJD isolated gramnegative anaerobs. The kangaroos were re-vaccinated after 1, 2, 6 and 12 months. Blood was collected from each animal at the same time. Antibodies were titrated against Fusobacterium necrophorum in an agglutination assay. The vaccine failed to induce increased levels of antibodies as well as to protect wallabies and kangaroos against LJD. As the highest antibody titres were detected in most severely diseased wallabies kept in the Hoyerswerda zoo, the protective role of the humoral immune response in LJD seems to be doubtful. The finding of detectable levels of antibodies in unvaccinated joeys supports the theory, that there is a transmission of antibodies from the mother to the offspring via colostrum or yolk-sac placenta. The diet of the Red-necked Wallabies in one zoo has induced an acidosis: The pH of the forestomach fluid collected by probang was lower in the animals of this zoo (pH = 7.53) than in the wallabies of two other zoos (pH = 8.25 and 8.38, respectively). Potassium, cholesterol and -amylase were also higher in the blood of the animals of this zoo in comparison to the wallabies of the two other ones, hence these blood values seem to be helpful for the diagnosis of chronic acidosis in macropods. There was a calcium and phosphor deficiency in the nutrition of the wallabies in two zoos, but the blood concentration of both of these minerals was not changed. The activity of the ALP correlated negative with the age of the Bennett`s Wallabies (P < 0.001, r = -.77 and r = -.62 respectively, depending on the instruments). All of the above mentioned blood values showed no differences between healthy and diseased animals and could so far not support the assumption, that an imbalance in Ca and P metabolism or an acidosis are important factors for LJD. The macropods of all investigated zoos were fed on a diet rich in vitamin A ranging from the 3.5 to the 41fold requirement for lambs. The vitamin A content of the diets for the 2 collections without a history of LJD was the lowest in this study. These results raised the point, that a hypervitaminosis A could be a more predisposing factor for LJD than a vitamin A deficiency. Due to the fact the plasma retinol concentration was independent from the vitamin A content of the diet and so not helpful in diagnosis of a vitamin A deficiency or toxicity, further investigations regarding the role of vitamin A in the aetiopathogenesis of LJD should include measurements of the liver tissue content of retinol esters. The glucose plasma concentration of the healthy Red Kangaroos (8.57 mmol/l) as well as the Red-necked Wallabies (6.51 mmol/l) was higher than previously published values for macropods, but also higher than the results of the diseased animals in this study. Therefore diabetes mellitus can be ruled out as an underlying factor for LJD. The analysis of 144 pathological records showed, that 30 animals died because of LJD, 20% of them and 16.7% of the other 114 macropods had a concurrent kidney disease. The urea and creatinin concentration in serum samples of healthy animals was not higher than the values of diseased animals. In conclusion, these results suggest kidney diseases are not important for the development of LJD. Altogether 184 sera collected from 107 kangaroos were tested for antibodies against MaHV-1 and MaHV-2 using a neutralisation assay. The prevalence of the MaHV-1- as well as MaHV-2-antibodies was high among the Red Kangaroos (94.4% and 97.2% respectively), but low among the Red-necked Wallabies (5.6% and 4.2% respectively). Seroconversion for MaHV-1 was seen in 2 out of 21 wallabies suffering from LJD, only 1 of these animals also had antibodies against MaHV-2. The antibody-titres against both of the macropodid herpes viruses also did not differ between Red Kangaroos with and without LJD, therefore a reactivation of a latent herpesvirus infection does not appear to be causative for LJD. In summary, considering the results of this study and previously published literature LJD is an infectious disease caused by gramnegative anaerobic bacteria with Fusobacterium nucleatum, Bacteroides spp., Porphyromonas gingivalis and Fusobacterium necrophorum subsp. necrophorum being of most significance. Recommendations concerning the keeping of kangaroos in captivity and the management of LJD are listed in the conclusion of this thesis. Some radiographs and photos of diseased and healthy kangaroos are attached
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11

Sun, Xida. "Structured Silicon Macropore as Anode in Lithium Ion Batteries". Wright State University / OhioLINK, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=wright1316470033.

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12

Ratcliffe, Elizabeth B. "Short-term hydrological responses of a forested hillslope during rainstorms, at Panola Mountain Research Watershed, Georgia, USA". Thesis, University of Bristol, 1996. http://hdl.handle.net/1983/099d7ff8-9ba5-41f8-ae62-78f063f8e8be.

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Abstract (sommario):
A small-scale filed experiment was conducted on a hillslope plot within the Georgia Piedmont, USA, with the aim of elucidating the hydrological processes which generate storm runoff and its chemistry. Intensive hydrometric and chemical sampling enabled the collection of detailed observations of hillslope processes during rainstorms. The passage of water was traced through a one-dimensional profile in the hillslope, where rainfall, throughfall, forest floor soil water, soil water at 15, 40, 50 and 70 cm depths, groundwaters and streamwaters were monitored, either manually or automatically. Chemical samples for each water type were also collected. From analysis of hydrometric data, several hydrological flowpaths were detected that contribute water to storm runoff. Direct channel rainfall is operative in all storms, although its detection is difficult. Overland flow is in operation at some locations on the hillslope, specially in topographic lows. Macropore and mesopore flow occurred and may lead to groundwater displacement. Groundwater ridging also occurred. Each flowpath was found to vary in its operation, according to a series of controls, namely seasonality, antecedent moisture conditions, rainfall magnitude, duration and intensity, and the timing between rainstorms. Conservative tracers (chloride and temperature) were employed to investigate the contribution of 'old' and 'new' water to storm runoff. The variation in chloride concentrations in samples collected either sequentially or manually at each flowpath was monitored throughout storms. Rainfall, comprising 'new' water, was found to exhibit a distinct chloride chemistry. Most samples contained < 20 μeq/l Cl⁻. A similar trend was observed for samples of through fall and forest floor soil water. Groundwaters and matrix soil waters contained two to three times greater chloride concentrations than in the 'new' waters, due to evaporative mechanisms. Hence, 'new' water could be distinguished from 'old' water on the basis of chloride chemistry. Similarly, the temperature profile of 'new' and 'old' waters were significantly different. During the summer, rainfall ('new' water) is warmer than groundwater ('old' water), and during the winter, the reverse is true. Hence, both chloride and temperature were instrumental in distinguishing 'old' from 'new' waters. Direct channel rainfall, overland flow and macropore flow were important flowpaths for the rapid transport of 'new' water through the system during the growing season. Overland flow contributed some 'old' water during the dormant season. Although macropore flow allowed rapid transit of 'new' water to depth, this led to a groundwater displacement mechanism, which ultimately led to the rapid contribution of 'old' water to storm runoff. The combination of hydrometric and tracer data enabled a conceptual hydrological model to be developed of the responses of the hillslope to storm events.
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13

Richings, Nadine Maree. "Growth, development and maturation of the marsupial follicle and oocyte /". Connect to thesis, 2004. http://eprints.unimelb.edu.au/archive/00001516.

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14

Kaluli, James Wambua. "Effect of macropores on infiltration and percolation: An experimental investigation". Thesis, University of Ottawa (Canada), 1990. http://hdl.handle.net/10393/5578.

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Abstract (sommario):
The purpose of this laboratory investigation was to study the effect of soil macropores (large non-capillary pores) on infiltration and percolation. This was done by measuring runoff, infiltration and tile flow rates for different macropore populations. The increase in percolation occurring as a result of increased number of macropores is associated with an increased bypass of the soil matrix by percolating water. The basic infiltration capacity increased with increasing number of macropores. This observation was used to develop the concept of macropore index (M-index). In situations where soil M-index changes seasonally, it becomes difficult for appropriate equation parameters to be determined accurately. To enable Horton equation to calculate infiltration in macroporous conditions, an improved form has been suggested. The influence of increasing the population of macropores on surface runoff and tile flow has been investigated. Results indicate that hydrologic models should consider the influence of macropores where populations are likely to change significantly over time. (Abstract shortened by UMI.)
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15

Foca, Eugen [Verfasser]. "Macropores in Si : fundamental study and prospective applications / Eugen Foca". Kiel : Universitätsbibliothek Kiel, 2008. http://d-nb.info/1019629452/34.

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16

Zuccolotto, Peter, of Western Sydney Nepean University e School of Science. "T-cell development in the Tammar wallaby (Macropus eugenii)". THESIS_XXXX_SS_Zuccolotto_P.xml, 2000. http://handle.uws.edu.au:8081/1959.7/391.

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Abstract (sommario):
Marsupials and eutherians are the two principal groups of modern mammals. Mammalian immunological studies, to date, have focused on eutherian systems with little or no comprehensive work having been carried out on marsupials. This project investigates the functional and developmental aspects of T-cell responses in the marsupial, Macropus eugenii (Tammar wallaby) in both adults and pouch young at various stages of development. Determination of the age at which the Tammar wallaby immune system becomes competent has been examined through the use of cellular and molecular studies carried out on developing pouch young tissue. The capacity for generating an immunological response in adult and pouch young marsupials has been studied by following cellular proliferation in response to mitogens or mixed lymphocyte culture (MLC). After examining adult responses to mitogens and allogenic lymphocytes, optimised conditions were then used to examine the development of responsiveness in pouch young. Several further tests were conducted and findings shown. The study has shown that the earliest age at which Macropus eugenii is capable of mounting a T-cell mediated immune response is between 5 to 13 days post-partum
Doctor of Philosophy (PhD)
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17

Zuccolotto, Peter. "T-cell development in the Tammar wallaby (Macropus eugenii)". Thesis, View thesis, 2000. http://handle.uws.edu.au:8081/1959.7/391.

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Abstract (sommario):
Marsupials and eutherians are the two principal groups of modern mammals. Mammalian immunological studies, to date, have focused on eutherian systems with little or no comprehensive work having been carried out on marsupials. This project investigates the functional and developmental aspects of T-cell responses in the marsupial, Macropus eugenii (Tammar wallaby) in both adults and pouch young at various stages of development. Determination of the age at which the Tammar wallaby immune system becomes competent has been examined through the use of cellular and molecular studies carried out on developing pouch young tissue. The capacity for generating an immunological response in adult and pouch young marsupials has been studied by following cellular proliferation in response to mitogens or mixed lymphocyte culture (MLC). After examining adult responses to mitogens and allogenic lymphocytes, optimised conditions were then used to examine the development of responsiveness in pouch young. Several further tests were conducted and findings shown. The study has shown that the earliest age at which Macropus eugenii is capable of mounting a T-cell mediated immune response is between 5 to 13 days post-partum
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18

Zuccolotto, Peter. "T-cell development in the Tammar wallaby (Macropus eugenii)". View thesis, 2000. http://library.uws.edu.au/adt-NUWS/public/adt-NUWS20030828.145055/index.html.

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19

Connelly, L. J. "Modelling stormflow in natural subsurface pipes". Thesis, Aberystwyth University, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.324211.

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20

Gibson, Craig Phillip, e res cand@acu edu au. "An Assessment of Animal Repellents in the Management of Vehicle-Macropod Collisions in New South Wales". Australian Catholic University. School of Arts and Sciences NSW, 2008. http://dlibrary.acu.edu.au/digitaltheses/public/adt-acuvp187.09122008.

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Abstract (sommario):
Collisions between animals and motor vehicles are frequent and often result in animal mortality. In Australia, macropods are regular victims of these collisions. This has serious implications for animal welfare and conservation as well as aesthetics and tourism. Collisions with large animals and secondary collisions caused by the presence of animals on road easements, can lead to serious personal injury and property damage. A range of mitigative measures to prevent animal-vehicle collisions exists, but no single measure can be fully effective and the efficacy of many mitigation measures remains untested. An integrated management approach, employing many mitigative techniques is required to reduce vehicle-animal collisions. Repellents have recently been identified as a potential mitigative measure for reducing vehicle-animal collisions. The aim of this study was to identify the potential role of repellents in reducing macropod-vehicle collisions in New South Wales. This required the identification and assessment of potential repellents since research investigating repellents in an Australian context is scant. Macropus rufogriseus banksianus was selected as a test species for this research as a high abundance of this species exists in southeastern Australia and it is a common victim of roadkill in New South Wales. Preliminary screening trials of four potential macropod repellents highlighted the utility of two of the substances: Plant Plus, a synthetic compound based on the chemistry of dog urine; and a formulation consisting of chicken eggs. Feeding by M. rufogriseus banksianus was significantly reduced when these substances were applied near feed trays. Modest results were also detected for Δ3-isopentenyl methyl sulfide (a constituent of fox urine), while a commercial animal repellent (SCAT® Bird and Animal Repellent) was ineffective in altering feeding by M. rufogriseus banksianus. A barrier trial conducted with the two most successful repellents indicated that Plant Plus was a more effective macropod repellent then the egg formulation. Plant Plus displayed qualities of an area repellent and elicited a stronger response from M. rufogriseus banksianus when compared to the egg formulation. Further captive trials determined that the habituation of response to Plant Plus by M. rufogriseus banksianus was minimal after six weeks of constant exposure and Plant Plus retained repellent properties after exposure to ambient environmental conditions for at least ten weeks. Field trials to establish the effectiveness of Plant Plus with free ranging macropods (M. rufogriseus banksianus and M. giganteus) were unsuccessful due to methodological limitations stemming from high background variance in observed responses, equipment failure and site disturbance from outside influences. The potential role of Plant Plus as a repellent for managing macropod-vehicle collisions was highlighted by the captive trials. However, several factors requiring further research were identified. This included assessing the repellent abilities of Plant Plus in the field and further defining the properties of Plant Plus with captive trials. The effects of Plant Plus on non-target species and an assessment of potential environmental impacts also requires attention. Research assessing the potential role of repellents in other management contexts in Australia would be beneficial and the identification and assessment of repellents for other species should proceed. However, in the context of assessing repellents for use in the management of vehicle-macropod collisions, immediate focus should concentrate on extending the research to assess the effects of Plant Plus with other species of large macropod, and assessing if Plant Plus can reduce the numbers of macropods in road easements.
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21

Weiler, Markus Helmut Weiler Markus Helmut. "Mechanisms controlling macropore flow during infiltration : dye tracer experiments and simulations /". Zürich : ETH, Eidgenössische Technische Hochschule Zürich, IHW, Institut für Hydromechanik und Wasserwirtschaft, 2001. http://e-collection.ethbib.ethz.ch/show?type=diss&nr=14237.

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22

Ishiguro, Munehide. "EFFECTS OF MACROPORES AND ELECTRIC CHARGES ON SOLUTE TRANSPORT IN SOILS". Kyoto University, 1992. http://hdl.handle.net/2433/78038.

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23

McEwen, Amiana Marie. "Abundance, Distribution, and Geometry of Naturally Occurring Macropores in Stream Banks". Thesis, Virginia Tech, 2018. http://hdl.handle.net/10919/95948.

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Abstract (sommario):
Preferential flow paths are areas of substantially higher permeability than surrounding media. Macropores and soil pipes are a type of preferential flow path where conduit-like voids in the subsurface are typically greater than three millimeters in diameter. They are known to occur in agricultural and forest soils, often as a result of biological and physical processes. Macropores also exist in stream banks and have the potential to enhance the exchange of water and solutes between the channel and riparian groundwater, yet the geographic distribution of bank macropores is unknown. Here we determined the abundance, distribution, and geometry of naturally occurring surface-connected macropores in the banks of 20 streams across five physiographic provinces in the Eastern United States. We identified a total of 1,748 macropores, which were present in all 20 streams, with 3.8 cm average width, 3.3 cm average height, 11.5 cm average depth, and 27.9 cm average height above water surface elevation. Macropore abundance, distribution and geometry were statistically different between physiographic provinces, stream orders, and soil textures, with the latter being the most important. Macropores tended to be larger and more abundant in soils with a high cohesiveness and a low hydraulic conductivity compared to soils with a low cohesiveness and high hydraulic conductivity. As a result, streams with greater longitudinal heterogeneity of soil texture also had greater heterogeneity of macropore density. However, macropore size and height above baseflow water surface elevation also increased with stream order and therefore stream size. This work represents the first attempt to characterize macropores across a variety of riverine systems and presents evidence that macropores may play an important role in hyporheic exchange within stream banks. These results may have water quality implications, where macropores may enhance hyporheic exchange yet reduce the filtering capacity of riparian buffer zones.
MS
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24

Gélin, Uriel. "Stratégies de reproduction des femelles du kangourou géant (Macropus giganteus)". Thèse, Université de Sherbrooke, 2014. http://savoirs.usherbrooke.ca/handle/11143/87.

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Abstract (sommario):
Résumé : La reproduction entraîne des dépenses énergétiques importantes chez les femelles mammifères. Ces dépenses sont supposées diminuer l'énergie disponible pour d'autres traits positivement corrélés à l'aptitude phénotypique et augmenter les besoins d'alimentation. Toutefois, des différences individuelles dans la capacité d'acquisition et d'allocation peuvent masquer l'impact négatif de l'effort reproducteur. La manipulation expérimentale de l'effort reproducteur et le contrôle statistique des effets individuels sont deux approches puissantes et complémentaires mises en œuvre dans le cadre de mon étude afin de contrôler pour l'hétérogénéité individuelle. Elles ont permis de montrer clairement un coût de la reproduction chez le kangourou gris de l'Est (Macropus giganteus). Dans un premier temps, nous avons trouvé que le coût de la reproduction affectait le montant d'énergie alloué à certaines fonctions somatiques (CHAPITRE I). L'effort reproducteur diminuait le gain de masse et la croissance des jambes pour des intervalles de capture supérieurs à deux ans. Chez les femelles non manipulées, un effet négatif sur le gain de masse était aussi observable pour un intervalle inférieur à 3 ans. À l'échelle de deux événements successifs de reproduction, le gain de masse et dans une moindre mesure la croissance des bras, mais non des jambes diminuaient avec un effort reproducteur plus important à la précédente reproduction. Ensuite, nous avons démontré qu'il y avait un coût de la reproduction en terme de futur succès reproducteur (CHAPITRE II). Les individus dont l'effort reproducteur avait été diminué expérimentalement produisaient davantage de jeunes qui survivaient au stade 'LPY', âgés approximativement de 7 mois, que les femelles contrôles. Ils diminuaient également davantage leur taux de reproduction en allongeant l'intervalle entre les naissances, mais la survie au sevrage n'était pas affectée. Le CHAPITRE III montre que les femelles adaptaient leur comportement alimentaire en fonction de leur statut reproducteur. En comparaison avec les individus manipulés ou ayant perdu leur jeune, les femelles allaitantes augmentaient leur temps passé à s'alimenter durant la journée, l'intensité de leurs bouchées et de leur mastication sans impliquer de compromis avec la vigilance. Nous avons aussi découvert que la survie au sevrage du jeune précédent menait à une augmentation du taux de bouchées pour l'année en cours. Les CHAPITRES I et II ont mis en évidence l'effet non négligeable des différences individuelles sur la détection des coûts de la reproduction. En effet, en l'absence de manipulation expérimentale ou de contrôle statistique, aucun compromis n'était détecté autant en terme de croissance que de prochaine reproduction. Au contraire, des corrélations positives entre l'effort reproducteur et les autres traits ont été trouvées. Le CHAPITRE I suggérait notamment que cette variabilité du succès reproducteur était liée à l'hétérogénéité individuelle dans le gain de masse maternelle qui augmentait la survie du jeune. Dans le CHAPITRE II, une corrélation positive entre les probabilités d'avoir un 'LPY' lors de deux événements successifs de reproduction suggérait que certaines femelles étaient capables de mener à bien ou non leur reproduction, mais cela indépendamment de l'effort reproducteur précédent. Enfin dans le dernier CHAPITRE (III), l'effet aléatoire était significatif dans l'analyse de différents comportements d'alimentation, ce qui pourrait être lié aux différences de gain de masse des femelles présentées dans le CHAPITRE I. Certaines contraintes individuelles affectant le coût de la reproduction ont été identifiées. La masse et la condition corporelle augmentaient le succès reproducteur et diminuaient l'intervalle entre deux naissances successives (CHAPITRES I et II), mais contrairement à de précédentes études le comportement d'alimentation des femelles n'était pas affecté par leur masse (CHAPITRE III). L'âge des individus avait également une influence. Les jeunes femelles croissaient davantage, avaient aussi une prise alimentaire plus importante et subissaient un coût de reproduction supérieur. Ce dernier se traduisait par un taux d'échec plus élevé à la reproduction suivante si les jeunes femelles avaient eu un jeune l'année précédente (CHAPITRES I, II et III). Des contraintes environnementales fortes influençaient la reproduction des femelles. La croissance, le succès reproducteur, l'intervalle entre les naissances et les comportements d'alimentation variaient suivant le site et l'année d'étude. Le site du Promontory et l'année 2011 apparaissaient particulièrement limitants. En effet en 2011, le gain de masse et le succès reproducteur ont diminué et l'intervalle de naissance et la prise de nourriture pour les femelles allaitantes ont augmenté (CHAPITRE I,II et III). Nous cherchions également à mettre au jour une allocation différentielle des mères suivant le sexe de leur jeune. Si le coût supérieur d'avoir un mâle par rapport à une femelle était évident quant aux taux de bouchées (CHAPITRE III), il s'est avéré plus difficile à détecter sur d'autres traits. À Anglesea, les jeunes mères avaient moins de probabilité d'avoir un jeune qui atteigne le stade 'LPY' après avoir eu un fils qu'une fille (CHAPITRE II). Toutefois, des résultats contraires à nos attentes ont été trouvés, du moins au premier abord, sur la croissance et le succès reproducteur subséquent. Ainsi, les femelles qui avaient eu une fille perdaient davantage de masse (CHAPITRE I) et avaient généralement une probabilité moindre de produire un jeune qui atteigne le stade 'LPY' ou qui soit sevré par la suite (CHAPITRE II). En revanche, l'intervalle de naissance n'était pas différent suivant le sexe du jeune alors qu'il était fortement affecté par le coût de la reproduction démontré grâce à la manipulation, invoquant une autre explication qu'un coût supérieur des filles par rapport aux fils. En effet, les femelles qui étaient en mauvaise condition corporelle gagnaient de la masse quand elles produisaient une fille, mais pas un fils (CHAPITRE I). De surcroît, les jeunes mères avaient moins de chances de sevrer un jeune à l'événement de reproduction suivant si elles avaient eu un fils plutôt qu'une fille, et le succès reproducteur des mères des fils n'était plus différent de celui des mères des filles dans les années plus difficiles (CHAPITRE II). Enfin, les mères des fils augmentaient la quantité de nourriture ingérée si elles avaient sevré un jeune l'année précédente, mais les mères des filles la diminuaient. Ces différents résultats suggéraient fortement qu'un ajustement du sexe-ratio était utilisé quand les ressources individuelles ou environnementales contraignaient davantage la reproduction. En conclusion, pour limiter le décalage entre les besoins énergétiques et la disponibilité en nourriture, les femelles chez le kangourou gris de l'Est pourraient modifier l'allocation de leurs ressources à la reproduction en reportant la prochaine mise bas et en produisant un jeune du sexe le moins coûteux en accord avec les contraintes individuelles et environnementales. Ces résultats soulignent l'importance d'études avec un suivi individuel sur plusieurs années afin de pouvoir comprendre la variabilité des stratégies de reproduction et leurs conséquences sur la dynamique des populations. // Abstract : Reproduction in living beings, particularly in female mammals that produce milk, is costly, potentially involving trade-offs with life-history traits if resources are limited and an increase in foraging effort. Individual differences may, however, hide the negative effects of this cost on life-history traits. I used two powerful and complementary approaches, to deal with individual heterogeneity: experimental manipulation of reproductive effort and statistical control of individual effect. Using both approaches, I investigated the effect of presence, size and sex of young on growth, subsequent reproduction and individual foraging behaviours of females. I used data of tagged free-ranging eastern grey kangaroos (Macropus giganteus) collected over six years at five study sites in Victoria, Australia. There was a clear cost of reproduction. Reproductive effort decreased mass gain and limb growth for inter-capture intervals greater than two years. Over two successive reproductive events, mass gain and arm growth were reduced but leg growth was independent of reproductive effort (CHAPTER II).In addition, survival to Large Pouch Young ('LPY') stage, about 7 months of age, was higher and birth rate lower in manipulated compared to control females but survival to weaning was not affected (CHAPTER III). CHAPTER IV shows that lactating females cope with current reproductive costs by increasing ivtime spent foraging as well as bite and chewing rates without decreasing vigilance comparedto non lactating ones. Bite rate was also greater for females that weaned a young at the previous reproductive event. My study supports reproductive cost hypothesis while showing substantial individual differences. To limit mismatch between energetic needs and resource availability, females of eastern grey kangaroo could modify resource allocation to reproduction by delaying birth date of subsequent young and producing the less costly sex according to individual and environmental constrains. My thesis shows the importance of experimental approach and individual monitoring over multiple years to understand the diversity of reproductive strategies and their consequences in evolutionary ecology and population dynamic.
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25

Combes, Anaïs Ducos de Lahitte Jacques. "Contribution à l'imagerie médicale du Wallaby de Bennett (Macropus rufogriseus)". [S.l.] : [s.n.], 2007. http://oatao.univ-toulouse.fr/1793/1/debouch_1793.pdf.

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26

Lu, Xuanming. "Preparation of Low-Valence Metal Oxide Monoliths with Three-Dimensionally Interconnected Macropores". Kyoto University, 2020. http://hdl.handle.net/2433/253113.

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27

Gibson, Craig Phillip. "An assessment of animal repellents in the management of vehicle-macropod collisions in New South Wales". Thesis, Australian Catholic University, 2008. https://acuresearchbank.acu.edu.au/download/e53cefd0417a4154d6827c1e150b300d382f640bef7cda01bb261f756d965ccd/7156229/64877_downloaded_stream_102.pdf.

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Collisions between animals and motor vehicles are frequent and often result in animal mortality. In Australia, macropods are regular victims of these collisions. This has serious implications for animal welfare and conservation as well as aesthetics and tourism. Collisions with large animals and secondary collisions caused by the presence of animals on road easements, can lead to serious personal injury and property damage. A range of mitigative measures to prevent animal-vehicle collisions exists, but no single measure can be fully effective and the efficacy of many mitigation measures remains untested. An integrated management approach, employing many mitigative techniques is required to reduce vehicle-animal collisions. Repellents have recently been identified as a potential mitigative measure for reducing vehicle-animal collisions. The aim of this study was to identify the potential role of repellents in reducing macropod-vehicle collisions in New South Wales. This required the identification and assessment of potential repellents since research investigating repellents in an Australian context is scant. Macropus rufogriseus banksianus was selected as a test species for this research as a high abundance of this species exists in southeastern Australia and it is a common victim of roadkill in New South Wales. Preliminary screening trials of four potential macropod repellents highlighted the utility of two of the substances: Plant Plus, a synthetic compound based on the chemistry of dog urine; and a formulation consisting of chicken eggs. Feeding by M. rufogriseus banksianus was significantly reduced when these substances were applied near feed trays. Modest results were also detected for ?3-isopentenyl methyl sulfide (a constituent of fox urine), while a commercial animal repellent (SCATREPLACE3 Bird and Animal Repellent) was ineffective in altering feeding by M. rufogriseus banksianus.;A barrier trial conducted with the two most successful repellents indicated that Plant Plus was a more effective macropod repellent then the egg formulation. Plant Plus displayed qualities of an area repellent and elicited a stronger response from M. rufogriseus banksianus when compared to the egg formulation. Further captive trials determined that the habituation of response to Plant Plus by M. rufogriseus banksianus was minimal after six weeks of constant exposure and Plant Plus retained repellent properties after exposure to ambient environmental conditions for at least ten weeks. Field trials to establish the effectiveness of Plant Plus with free ranging macropods (M. rufogriseus banksianus and M. giganteus) were unsuccessful due to methodological limitations stemming from high background variance in observed responses, equipment failure and site disturbance from outside influences. The potential role of Plant Plus as a repellent for managing macropod-vehicle collisions was highlighted by the captive trials. However, several factors requiring further research were identified. This included assessing the repellent abilities of Plant Plus in the field and further defining the properties of Plant Plus with captive trials. The effects of Plant Plus on non-target species and an assessment of potential environmental impacts also requires attention. Research assessing the potential role of repellents in other management contexts in Australia would be beneficial and the identification and assessment of repellents for other species should proceed. However, in the context of assessing repellents for use in the management of vehicle-macropod collisions, immediate focus should concentrate on extending the research to assess the effects of Plant Plus with other species of large macropod, and assessing if Plant Plus can reduce the numbers of macropods in road easements.
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28

Lane, Meg. "Sperm competition and sexual selection in western grey kangaroos Macropus fuliginosus". Thesis, Lane, Meg (2014) Sperm competition and sexual selection in western grey kangaroos Macropus fuliginosus. Honours thesis, Murdoch University, 2014. https://researchrepository.murdoch.edu.au/id/eprint/25342/.

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Macropods exhibit the second largest sexual dimorphism in body size for any vertebrate, suggesting there is a major role of sexual selection, with the potential for different mating tactics amongst male kangaroos. It is suggested that dominant males invest heavily in large forelimb muscles, which aids in male-male competition, female coercion and increased attractiveness to females, gaining them the majority of matings. A subdominant male may not invest in muscle mass development, but rather rely on other reproductive tactics such as sneaky matings and investment in competitive spermatozoa characteristics; for example more spermatozoa (larger testes) and faster or longer spermatozoa. We examined whether there was a trade-off between investments in forelimb muscle development and sperm competition in the western grey kangaroo (Macropus fuliginosus). Sperm traits, body mass, and forelimb muscle masses were measured for 35 male M. fuliginosus and an index of ‘muscularity’ was calculated using the residuals of individual muscle masses against body mass. There were no significant relationships between forelimb muscle investment and sperm competition traits. Significant relationships were recorded between relative testes mass and relative epididymis mass (r2 = 0.26, p = 0.003), total motility and progressive motility (r2 = 0.31, p = 0.001) and spermatozoon velocity and spermatozoon head (r2 = 0.47, p < 0.001) and tail lengths (r2 = 0.19, p = 0.011) with the longer spermatozoa swimming slower. These results suggest that there is no evidence for a significant relationship between sperm competition and forelimb muscles. There was no evidence for a trade-off between these two measures of sexual selection, suggesting that these traits are independent of each other.
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29

Lapidge, Steven James. "Reintroduction biology of yellow-footed rock wallabies (petrogale xanthopus celeris and P. x. xanthopus". University of Sydney. Biological Sciences, 2002. http://hdl.handle.net/2123/851.

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Based on the recommendations of both the 1993 Reintroduction biology of Australasian Fauna Conference and the 1994 Rock Wallaby Symposium, captive-bred Yellow footed rock wallabies were reintroduced into areas of their former ranges in both South Australia and Queensland
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30

Chambers, Brian Kevan. "Human disturbance affects the ecology and population dynamics of the tammar wallaby, Macropus eugenii, on Garden Island, Western Australia". University of Western Australia. School of Animal Biology, 2009. http://theses.library.uwa.edu.au/adt-WU2009.0139.

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[Truncated abstract] Understanding the effect that the disturbance of habitat by humans has on the population dynamics and ecology of wild animals is critical for the management of these populations. By understanding the demographic effects of disturbance the ways in which a population can be managed to increase or decrease its rate of change in size also become apparent. This thesis describes the effect that human disturbance, through the establishment of a large naval base, has had on the population dynamics and ecology of tammar wallabies (Macropus eugenii) on Garden Island, Western Australia. The disturbance of the environment on the HMAS Stirling Naval Base included the establishment of large areas of irrigated and fertilised couch grass (Cynodon dactylon) that increased and made virtually constant the amount of food available to the tammars in that area. In addition, traffic associated with the naval base resulted in large numbers of tammar wallabies being killed by vehicles. The effects of these disturbances were determined by comparing population dynamics, through vital rates of survival and fecundity and population growth rates, and spatial ecology, through the size of the animals' home ranges, in three areas of Garden Island. The three areas were the naval base (highly disturbed), southern bushland (adjacent to the naval base) and the northern bushland (undisturbed). The tammars on the naval base were in better body condition than those living in the two bushland areas of the island. ... When the impact of road-kills was removed, increased to 1.150.101 per year on the naval base and 0.960.076 per year in the southern bushland. Fecundity transitions, defined as the product of the rates of birth and pouch-young survival, and adult survival rates were lower in the bushland areas compared with the naval base in two of the three years, which were the main reasons for the lower estimates. There were no significant differences in the size of the tammars' home ranges between areas with modified or unmodified habitats or between the sexes (P>0.05). In summer the mean size of the home ranges was 3.90.66 ha, which was larger than winter when home ranges were 3.20.54 ha, but this difference failed to reach significance (P=0.058). These results indicate that the modification of the tammars' habitat has probably not caused significant changes in the size of the animals' home ranges. The size of the home ranges of tammar wallabies is likely to be determined by a complex interaction of many factors, and habitat modification alone has not been sufficient to cause substantial changes. The results presented in this thesis demonstrate that the disturbance caused by the establishment of the naval base on Garden Island has altered the population dynamics of the tammars wallabies, through increasing in the amount of food available to the tammars and through high numbers of road-kills. These results also demonstrate how gaining detailed knowledge of population dynamics can have direct application to managing the impact of disturbance on populations of wild animals.
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31

Frey, Stefan. "Novel formation regimes and mechanisms for macropores and porous anodic oxides in silicon". [S.l.] : [s.n.], 2005. http://e-diss.uni-kiel.de/diss_1607/d1607.pdf.

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32

Fazenda, Inês Isabel Paulo. "Molecular and morphological characterization of the genus globocephaloides from macropodid marsupials in Australia". Bachelor's thesis, Universidade Técnica de Lisboa. Faculdade de Medicina Veterinária, 2009. http://hdl.handle.net/10400.5/1302.

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Dissertação de Mestrado Integrado em Medicina Veterinária
The genus Globocephaloides (Nematoda: Trichostrongyloidea) is a pathogenic group of parasitic nematodes present in the duodenum of kangaroos and wallabies (Marsupialia: Macropodidae) in Australia. Globocephaloides species (G. trifidospicularis, G. macropodis and G. affinis) have been poorly studied and thus, there are significant controversies regarding their systematics and population structures. In the present study, single-strand conformation polymorphism (SSCP) and targeted sequencing of the internal transcribed spacers (ITS) of nuclear ribosomal DNA, were used to assess the genetic variation within and among Globocephaloides populations and individuals, from different host species and geographical origins. No or minor (0.2%) variation was detected among individuals of G. trifidospicularis and G. affinis. However, within G. macropodis populations there was a consistent heterogeneity in the ITS sequences (5.2 - 7.1%) between worms derived from two different host species (Macropus agilis and M. dorsalis). Under light microscopy, these two G. macropodis genotypes differed by the length, arrangement and tip of the spicules, and by pattern of the bursal rays. Thus, they were considered to represent sibling species. The molecular and morphological evidence culminated with the erection of a new species, namely G. wallabiae, and provided further insights into the host affiliation and geographical ranges of Globocephaloides spp.: G. wallabiae occurs mainly in M. dorsalis (north/east), G. macropodis in M. agilis and Petrogale persephone (north), G. affinis in M. dorsalis (north-east), and G. trifidospicularis in various Macropus species (south). Moreover, in the present study, the phylogenetic analyses between the genus Globocephaloides and other trichostrongyloid genera, using divergent domains of the 28S rRNA genes, gave evidence for the exclusion of the genus Globocephaloides from the Herpetostrongylidae, with the suggestion of a new family, namely „Globocephaloididae‟, within the Heligmosomoidea.
RESUMO - CARACTERIZAÇÃO MOLECULAR E MORFOLÓGICA DO GÉNERO GLOBOCEPHALOIDES EM MARSUPIAIS MACROPODÍDEOS NA AUSTRÁLIA - O género Globocephaloides (Nematoda: Trichostrongyloidea) é um importante grupo de nemátodes patogénicos presente no duodeno de cangurus e wallabies (Marsupialia: Macropodidae) na Austrália. O estudo das espécies de Globocephaloides (G. trifidospicularis, G. macropodis e G. affinis) tem sido limitado, e por isso, existem numerosas controvérsias em relação à sua sistemática e às suas estruturas populacionais. No presente estudo, as técnicas de análise de ácidos nucleicos, „single-strand conformation polymorphism‟ (SSCP) e sequenciação-alvo da região ITS („internal transcribed spacers‟) do DNA ribossomal foram usadas com o objectivo de analisar a variação genética entre indivíduos e populações de Globocephaloides provenientes de diferentes hospedeiros e áreas geográficas. Em ambas as espécies G. trifidospicularis e G. affinis pouca ou nenhuma variação foi encontrada (0.2%). Contudo, nas populações de G. macropodis foi detectada uma consistente heterogeneidade nas sequências ITS (5.2 - 7.1%) entre espécimes provenientes de dois hospedeiros distintos (Macropus agilis e M. dorsalis). Recorrendo à microscopia óptica verificou-se que os dois genótipos de G. macropodis diferiam no comprimento, conformação e ponta das espículas, assim como, no padrão dos raios da bolsa copuladora. Como tal, foi considerado que os dois genótipos representavam duas espécies congéneres. Os resultados da biologia molecular e do estudo morfológico determinaram o reconhecimento de uma nova espécie denominada G. wallabiae e, além disso, forneceram dados sobre a especificidade de hospedeiros e distribuição geográfica do género Globocephaloides. G. wallabiae ocorre principalmente no hospedeiro M. dorsalis (norte/este), G. macropodis no M. agilis e Petrogale persephone (norte), G. affinis no M. dorsalis (nordeste) e G. trifidospicularis em várias espécies do género Macropus (sul). Adicionalmente, a análise das relações filogenéticas entre o género Globocephaloides e outros tricostrongilídeos, empregando os domínios do gene 28S rRNA, deu provas para a exclusão do género Globocephaloides da família Herpetostrongylidae, com a sugestão de uma nova família, denominada „Globocephalidae‟, inserida na superfamília Heligmosomoidea.
Financial support provided to the supervisors for the present study was from bodies including the Australian Research Council (ARC) [to Robin B. Gasser] and Australian Biological Resources Study (ABRS) [to Ian Beveridge]
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33

Kobayashi, Katsutoshi. "Formation of Ordered Macropores in p-Type Silicon and Their Application to Templates". Kyoto University, 2009. http://hdl.handle.net/2433/123890.

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Kyoto University (京都大学)
0048
新制・課程博士
博士(エネルギー科学)
甲第14737号
エネ博第190号
新制||エネ||43(附属図書館)
UT51-2009-D449
京都大学大学院エネルギー科学研究科エネルギー基礎科学専攻
(主査)教授 尾形 幸生, 教授 萩原 理加, 准教授 作花 哲夫
学位規則第4条第1項該当
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34

Akay, Onur. "Laboratory experiments and numerical modeling of the interconnectivity of macropores and subsurface drainage /". Full text available from ProQuest UM Digital Dissertations, 2007. http://0-proquest.umi.com.umiss.lib.olemiss.edu/pqdweb?index=0&did=1609001651&SrchMode=1&sid=4&Fmt=2&VInst=PROD&VType=PQD&RQT=309&VName=PQD&TS=1244736298&clientId=22256.

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35

Frutuoso, Leonel Faria. "Clínica de animais selvagens e de zoo". Master's thesis, Universidade de Évora, 2015. http://hdl.handle.net/10174/14575.

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O presente relatório resulta do estágio curricular subordinado ao tema Clínica de Animais Selvagens e de Zoo, decorrido no Zoo de Dalas (E.U.A.) e no Zoo da Maia, com duração de 97 dias partilhados entre as duas instituições. Surge na conclusão do Mestrado Integrado em Medicina Veterinária da Universidade de Évora A doença periodontal refere-se, geralmente, a alterações que envolvem os dentes e os tecidos adjacentes da cavidade oral e apresenta, na maioria das vezes, etiologia bacteriana associada a alterações da flora microbiana oral. A necrobacilose oral é uma causa comum de morbilidade e mortalidade nos animais do género Macropus, podendo ser o resultado do agravamento da doença periodontal e manifestando-se por lesões supurativas no tecido mole e ossos da face, sendo o Fusobacterium necrophorum o principal agente causal; ABSTRACT: Zoo and Wildlife Medicine The following report results from the externship in Zoo and Wildlife Medicine lasting 97 days, shared between Dalas Zoo (U.S.A.) and Maia Zoo. Appears as the conclusion of the Master in Veterinary Medicine at the University of Évora Periodontal disease generally describes the conditions involving the teeth and adjoining tissues of the oral cavity and presents mostly a bacterial etiology associated with changes in oral microbial flora. Oral necrobacillosis is a common cause of morbidity and mortality in animals of the genus Macropus and may be the result of the progress of periodontal disease, manifesting as suppurative lesions of the soft tissue and bones of the face and the main causal agent seems to be Fusobacterium necrophorum.
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36

G??lin, Uriel. "Strat??gies de reproduction des femelles du kangourou g??ant (Macropus giganteus)". Thèse, Universit?? de Sherbrooke, 2014. http://savoirs.usherbrooke.ca/handle/11143/87.

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R??sum?? : La reproduction entra??ne des d??penses ??nerg??tiques importantes chez les femelles mammif??res. Ces d??penses sont suppos??es diminuer l'??nergie disponible pour d'autres traits positivement corr??l??s ?? l'aptitude ph??notypique et augmenter les besoins d'alimentation. Toutefois, des diff??rences individuelles dans la capacit?? d'acquisition et d'allocation peuvent masquer l'impact n??gatif de l'effort reproducteur. La manipulation exp??rimentale de l'effort reproducteur et le contr??le statistique des effets individuels sont deux approches puissantes et compl??mentaires mises en ??uvre dans le cadre de mon ??tude afin de contr??ler pour l'h??t??rog??n??it?? individuelle. Elles ont permis de montrer clairement un co??t de la reproduction chez le kangourou gris de l'Est (Macropus giganteus). Dans un premier temps, nous avons trouv?? que le co??t de la reproduction affectait le montant d'??nergie allou?? ?? certaines fonctions somatiques (CHAPITRE I). L'effort reproducteur diminuait le gain de masse et la croissance des jambes pour des intervalles de capture sup??rieurs ?? deux ans. Chez les femelles non manipul??es, un effet n??gatif sur le gain de masse ??tait aussi observable pour un intervalle inf??rieur ?? 3 ans. ?? l'??chelle de deux ??v??nements successifs de reproduction, le gain de masse et dans une moindre mesure la croissance des bras, mais non des jambes diminuaient avec un effort reproducteur plus important ?? la pr??c??dente reproduction. Ensuite, nous avons d??montr?? qu'il y avait un co??t de la reproduction en terme de futur succ??s reproducteur (CHAPITRE II). Les individus dont l'effort reproducteur avait ??t?? diminu?? exp??rimentalement produisaient davantage de jeunes qui survivaient au stade 'LPY', ??g??s approximativement de 7 mois, que les femelles contr??les. Ils diminuaient ??galement davantage leur taux de reproduction en allongeant l'intervalle entre les naissances, mais la survie au sevrage n'??tait pas affect??e. Le CHAPITRE III montre que les femelles adaptaient leur comportement alimentaire en fonction de leur statut reproducteur. En comparaison avec les individus manipul??s ou ayant perdu leur jeune, les femelles allaitantes augmentaient leur temps pass?? ?? s'alimenter durant la journ??e, l'intensit?? de leurs bouch??es et de leur mastication sans impliquer de compromis avec la vigilance. Nous avons aussi d??couvert que la survie au sevrage du jeune pr??c??dent menait ?? une augmentation du taux de bouch??es pour l'ann??e en cours. Les CHAPITRES I et II ont mis en ??vidence l'effet non n??gligeable des diff??rences individuelles sur la d??tection des co??ts de la reproduction. En effet, en l'absence de manipulation exp??rimentale ou de contr??le statistique, aucun compromis n'??tait d??tect?? autant en terme de croissance que de prochaine reproduction. Au contraire, des corr??lations positives entre l'effort reproducteur et les autres traits ont ??t?? trouv??es. Le CHAPITRE I sugg??rait notamment que cette variabilit?? du succ??s reproducteur ??tait li??e ?? l'h??t??rog??n??it?? individuelle dans le gain de masse maternelle qui augmentait la survie du jeune. Dans le CHAPITRE II, une corr??lation positive entre les probabilit??s d'avoir un 'LPY' lors de deux ??v??nements successifs de reproduction sugg??rait que certaines femelles ??taient capables de mener ?? bien ou non leur reproduction, mais cela ind??pendamment de l'effort reproducteur pr??c??dent. Enfin dans le dernier CHAPITRE (III), l'effet al??atoire ??tait significatif dans l'analyse de diff??rents comportements d'alimentation, ce qui pourrait ??tre li?? aux diff??rences de gain de masse des femelles pr??sent??es dans le CHAPITRE I. Certaines contraintes individuelles affectant le co??t de la reproduction ont ??t?? identifi??es. La masse et la condition corporelle augmentaient le succ??s reproducteur et diminuaient l'intervalle entre deux naissances successives (CHAPITRES I et II), mais contrairement ?? de pr??c??dentes ??tudes le comportement d'alimentation des femelles n'??tait pas affect?? par leur masse (CHAPITRE III). L'??ge des individus avait ??galement une influence. Les jeunes femelles croissaient davantage, avaient aussi une prise alimentaire plus importante et subissaient un co??t de reproduction sup??rieur. Ce dernier se traduisait par un taux d'??chec plus ??lev?? ?? la reproduction suivante si les jeunes femelles avaient eu un jeune l'ann??e pr??c??dente (CHAPITRES I, II et III). Des contraintes environnementales fortes influen??aient la reproduction des femelles. La croissance, le succ??s reproducteur, l'intervalle entre les naissances et les comportements d'alimentation variaient suivant le site et l'ann??e d'??tude. Le site du Promontory et l'ann??e 2011 apparaissaient particuli??rement limitants. En effet en 2011, le gain de masse et le succ??s reproducteur ont diminu?? et l'intervalle de naissance et la prise de nourriture pour les femelles allaitantes ont augment?? (CHAPITRE I,II et III). Nous cherchions ??galement ?? mettre au jour une allocation diff??rentielle des m??res suivant le sexe de leur jeune. Si le co??t sup??rieur d'avoir un m??le par rapport ?? une femelle ??tait ??vident quant aux taux de bouch??es (CHAPITRE III), il s'est av??r?? plus difficile ?? d??tecter sur d'autres traits. ?? Anglesea, les jeunes m??res avaient moins de probabilit?? d'avoir un jeune qui atteigne le stade 'LPY' apr??s avoir eu un fils qu'une fille (CHAPITRE II). Toutefois, des r??sultats contraires ?? nos attentes ont ??t?? trouv??s, du moins au premier abord, sur la croissance et le succ??s reproducteur subs??quent. Ainsi, les femelles qui avaient eu une fille perdaient davantage de masse (CHAPITRE I) et avaient g??n??ralement une probabilit?? moindre de produire un jeune qui atteigne le stade 'LPY' ou qui soit sevr?? par la suite (CHAPITRE II). En revanche, l'intervalle de naissance n'??tait pas diff??rent suivant le sexe du jeune alors qu'il ??tait fortement affect?? par le co??t de la reproduction d??montr?? gr??ce ?? la manipulation, invoquant une autre explication qu'un co??t sup??rieur des filles par rapport aux fils. En effet, les femelles qui ??taient en mauvaise condition corporelle gagnaient de la masse quand elles produisaient une fille, mais pas un fils (CHAPITRE I). De surcro??t, les jeunes m??res avaient moins de chances de sevrer un jeune ?? l'??v??nement de reproduction suivant si elles avaient eu un fils plut??t qu'une fille, et le succ??s reproducteur des m??res des fils n'??tait plus diff??rent de celui des m??res des filles dans les ann??es plus difficiles (CHAPITRE II). Enfin, les m??res des fils augmentaient la quantit?? de nourriture ing??r??e si elles avaient sevr?? un jeune l'ann??e pr??c??dente, mais les m??res des filles la diminuaient. Ces diff??rents r??sultats sugg??raient fortement qu'un ajustement du sexe-ratio ??tait utilis?? quand les ressources individuelles ou environnementales contraignaient davantage la reproduction. En conclusion, pour limiter le d??calage entre les besoins ??nerg??tiques et la disponibilit?? en nourriture, les femelles chez le kangourou gris de l'Est pourraient modifier l'allocation de leurs ressources ?? la reproduction en reportant la prochaine mise bas et en produisant un jeune du sexe le moins co??teux en accord avec les contraintes individuelles et environnementales. Ces r??sultats soulignent l'importance d'??tudes avec un suivi individuel sur plusieurs ann??es afin de pouvoir comprendre la variabilit?? des strat??gies de reproduction et leurs cons??quences sur la dynamique des populations. // Abstract : Reproduction in living beings, particularly in female mammals that produce milk, is costly, potentially involving trade-offs with life-history traits if resources are limited and an increase in foraging effort. Individual differences may, however, hide the negative effects of this cost on life-history traits. I used two powerful and complementary approaches, to deal with individual heterogeneity: experimental manipulation of reproductive effort and statistical control of individual effect. Using both approaches, I investigated the effect of presence, size and sex of young on growth, subsequent reproduction and individual foraging behaviours of females. I used data of tagged free-ranging eastern grey kangaroos (Macropus giganteus) collected over six years at five study sites in Victoria, Australia. There was a clear cost of reproduction. Reproductive effort decreased mass gain and limb growth for inter-capture intervals greater than two years. Over two successive reproductive events, mass gain and arm growth were reduced but leg growth was independent of reproductive effort (CHAPTER II).In addition, survival to Large Pouch Young ('LPY') stage, about 7 months of age, was higher and birth rate lower in manipulated compared to control females but survival to weaning was not affected (CHAPTER III). CHAPTER IV shows that lactating females cope with current reproductive costs by increasing ivtime spent foraging as well as bite and chewing rates without decreasing vigilance comparedto non lactating ones. Bite rate was also greater for females that weaned a young at the previous reproductive event. My study supports reproductive cost hypothesis while showing substantial individual differences. To limit mismatch between energetic needs and resource availability, females of eastern grey kangaroo could modify resource allocation to reproduction by delaying birth date of subsequent young and producing the less costly sex according to individual and environmental constrains. My thesis shows the importance of experimental approach and individual monitoring over multiple years to understand the diversity of reproductive strategies and their consequences in evolutionary ecology and population dynamic.
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37

Holden, Joseph. "Runoff production in blanket peat covered catchments". Thesis, Durham University, 2000. http://etheses.dur.ac.uk/4264/.

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Although blanket peat covers many major headwater areas in Britain, runoff production within these upland catchments is poorly understood. This thesis examines runoff production mechanisms within the blanket peat catchments of the Moor House National Nature Reserve, North Pennines, UK. Catchments ranging from 11.4 km^ down to the hillslope and plot-scale are examined. Runoff from the monitored catchments was flashy. Lag times are short and rainwater is efficiently transported via quickflow- generating mechanisms such that flood peaks are high and low flows poorly maintained. Hillslope and plot-scale runoff measurements show that the flashy catchment response is the result of the dominance of overland flow. Typically 80 % of runoff is produced as overland flow. This occurs both on bare and vegetated surfaces. Most of the remaining runoff is generated from the upper 10 cm of the peat, except where well-connected macropore and pipe networks transfer flow through the lower layers. Below 10 cm depth the blanket peat matrix fails to contribute any significant runoff Thus most groundwater-based models of peat hydrological process are not readily applicable to these catchments. Suggestions that infiltration-excess overland flow may be largely responsible for the flashy regime of these upland catchments are not substantiated by the blanket peat infiltration data presented in this thesis. Monitoring of hillslope runoff mechanisms combined with rainfall simulation (at realistic intensities of 3-12 mm hr(^-1)) and tension- infiltrometer experiments shows that saturation-excess mechanisms dominate the response. Infiltration is relatively rapid in the upper peat layers until they become saturated and overland flow begins. High water tables result in rapid saturation of the peat mass such that even at low rainfall intensity runoff production is just as efficient as during high intensity events. While macropores have largely been ignored in blanket peat, results presented suggest that up to 30 % of runoff may be generated through them. Occasionally these macropore networks develop through the deeper peat such that runoff bypasses the matrix and runs off at depth from small outlets and larger pipe networks. Seasonal variations in runoff- generating processes can be exacerbated by drought which causes structural changes to the near-surface of the peat. This was found to result in enhanced infiltration and macropore flow which may encourage pipe network development. Flow has been monitored simultaneously from several natural pipes in a 0.4 km(^2) headwater catchment of the Tees. This catchment provides one of the few examples of pipeflow monitoring outside the shallow peaty-podzols of mid-Wales. Natural pipes are found throughout the soil profile and can be at depths of up to three metres. Ground penetrating radar was useful in identifying deep subsurface piping and suggestions are made for improvements to the application. The pipe networks were found to be complex and results demonstrate that outlet location and size may bear little relation to the form and depth of the pipe a short distance upslope. Pipes generally contribute less than 10 % to catchment runoff but on the rising and falling hydrograph limbs can contribute over 30 % to streamflow. Pipeflow lag times are short suggesting that both the shallow and deep pipes may be well connected to the surface. Thus while matrix runoff contributions at depth within the peat may be low, macropore flow mechanisms can be significant.
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38

Badel, Xavier. "Development of macropore arrays in silicon and related technologies for X-ray imaging applications". Licentiate thesis, KTH, Microelectronics and Information Technology, IMIT, 2003. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-1623.

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Digital devices have started to replace photographic film inX-ray imaging applications. As compared to photographic films,these devices are more convenient to obtain images and tohandle, treat and store these images. The goal of the presentstudy is to develop macropore arrays and related silicontechnologies in order to fabricate X-ray imaging detectors formedical applications, and in particular for dentistry. Althougha few detectors are already available on the market, theirperformances, such as the X-ray sensitivity, can still beimproved. In addition, the image quality, defined by thespatial resolution and the signalto- noise ratio (SNR), shouldbe sufficiently high to enable diagnosis and, as regard to thepatient health, the X-ray dose should be reduced to aminimum.

Three detector concepts were investigated. All of themrequire the formation of a macropore array in silicon as afirst step in the detector fabrication. Even though deepreactive ion etching was used to form these macropore arrays,silicon electrochemical etching in aqueous hydrofluoric acid(HF) solution has been more intensively studied. The porespacing was fixed to about 50 µm in order to achieve aspatial resolution of 10 lp/mm, as required in dentalapplication. Pore depths up to 420 µm with diameterranging from 10 to 40 µm, depending on the detectorconcept, have been achieved. Electrochemical etching of siliconis, indeed, a very promising technique to fabricate high aspectratio structures and damage-free macropore arrays. Thistechnique is based on a silicon dissolution reaction involvingthe species of the HF solution, silicon atoms and holes, thepositive charge carriers. As holes are the minority carriers inn-type silicon, they are usually photogenerated. However, wealso developed an alternative technique based on hole injectionfrom a forwardbiased p-n junction, and the possibility to formmacropore arrays and diverse threedimensional structures wasdemonstrated.

The first detector concept investigated consists of asilicon charge-coupled device (CCD) in proximity with ascintillating guide screen. This screen is made of a siliconmacropore array filled with CsI(Tl), emitting photons at awavelength of 550 nm (green light) under X-ray exposure. Thevisible light is then reflected on the walls of the pores inorder to be detected by the CCD pixels. Both oxide and metalcan be used as a reflective layer. Such detectors were fullyfabricated and characterized, showing good spatial resolutionand comparable results with currently available detectorsconcerning the SNR and the X-ray dose. The second detectorstudied in this thesis uses photodiodes, instead of a CCD, inorder to detect the photons emitted from the scintillator. Thisconcept would lead to high charge collection efficiency sincethe diodes are formed in the silicon pore walls, making thedistance between the generation and detection points of thevisible photons short. However, this design implies two majordifficulties in the detector fabrication: formation of p-njunction in the pore walls and formation of contacts to thediodes. Thus, boron diffusion from a solid source andlow-pressure chemical vapor deposition of boron-dopedpoly-silicon were experimented. Both techniques were shown tobe successful. The last detector concept is based on thegeneration of electron/hole pairs in the semiconductor bulkunder X-ray exposure. The generated charges would then becollected by electrodes going through the bulk, requiringformation of deep and narrow pores. Siliconphoto-electrochemical etching was used and 425-µm deeppores with a diameter of 14 µm were formed, resulting inan aspect ratio of ~ 30 and an active area of 90 %.

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39

Asare, Seth Ntiri. "Investigation of soil macroporosity and macropore flow in agricultural soils using volume CT scanner". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape11/PQDD_0007/NQ40361.pdf.

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40

McDonald, Douglas Joseph. "The role of macropores in subsurface flow on a forested slope, an experimental investigation". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp03/MQ40480.pdf.

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41

Mori, Yasushi. "SOFT X-RAY VISUALIZATION AND ANALYSIS ON HYDRAULIC AND GEOMETRICAL PROPERTIES OF SOIL MACROPORE". Kyoto University, 1999. http://hdl.handle.net/2433/182434.

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42

Vivian, Benjamin James. "The role of rapid recharge processes in the initiation of landslides". Thesis, University of Oxford, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.286619.

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43

Vasenkov, Sergey, e Pavel Kortunov. "PFG NMR measurements of tortuosity factors for diffusion in meso- and macropores of FCC catalysts". Universitätsbibliothek Leipzig, 2016. http://nbn-resolving.de/urn:nbn:de:bsz:15-qucosa-197145.

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Abstract (sommario):
Pulsed field gradient (PFG) NMR is applied to measure self-diffusion coefficients of 1,3,5 tri-isopropyl-benzene in the particles of several industrial FCC catalysts having different systems of meso- and macropores. Relating these diffusivities to the self-diffusion coefficient of 1,3,5 tri-isopropyl-benzene in the liquid phase, the tortuosity factors for diffusion in the meso- and macropores of the particles were obtained. The values of the tortuosity factors were found to increase with a increasing volumetric fraction of the small (< 20 nm) meso- and macropores in the total intraparticle volume.
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44

Naveed, Muhammad, Per Moldrup, Marcel G. Schaap, Markus Tuller, Ramaprasad Kulkarni, Hans-Jörg Vogel e de Jonge Lis Wollesen. "Prediction of biopore- and matrix-dominated flow from X-ray CT-derived macropore network characteristics". COPERNICUS GESELLSCHAFT MBH, 2016. http://hdl.handle.net/10150/621951.

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Prediction and modeling of localized flow processes in macropores is of crucial importance for sustaining both soil and water quality. However, currently there are no reliable means to predict preferential flow due to its inherently large spatial variability. The aim of this study was to investigate the predictive performance of previously developed empirical models for both water and air flow and to explore the potential applicability of X-ray computed tomography (CT)-derived macropore network characteristics. For this purpose, 65 cylindrical soil columns (6 cm diameter and 3.5 cm height) were extracted from the topsoil (5 cm to 8.5 cm depth) in a 15 m  ×  15 m grid from an agricultural field located in Silstrup, Denmark. All soil columns were scanned with an industrial X-ray CT scanner (129 µm resolution) and later employed for measurement of saturated hydraulic conductivity, air permeability at −30 and −100 cm matric potential, and gas diffusivity at −30 and −100 cm matric potential. Distribution maps for saturated hydraulic conductivity, air permeability, and gas diffusivity reflected no autocorrelation irrespective of soil texture and organic matter content. Existing empirical predictive models for saturated hydraulic conductivity and air permeability showed poor performance, as they were not able to realistically capture macropore flow. The tested empirical model for gas diffusivity predicted measurements at −100 cm matric potential reasonably well, but failed at −30 cm matric potential, particularly for soil columns with biopore-dominated flow. X-ray CT-derived macroporosity matched the measured air-filled porosity at −30 cm matric potential well. Many of the CT-derived macropore network characteristics were strongly interrelated. Most of the macropore network characteristics were also significantly correlated with saturated hydraulic conductivity, air permeability, and gas diffusivity. The predictive Ahuja et al. (1984) model for saturated hydraulic conductivity, air permeability, and gas diffusivity performed reasonably well when parameterized with novel, X-ray CT-derived parameters such as effective percolating macroporosity for biopore-dominated flow and total macroporosity for matrix-dominated flow. The obtained results further indicate that it is crucially important to discern between matrix-dominated and biopore-dominated flow for accurate prediction of macropore flow from X-ray CT-derived macropore network characteristics.
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45

Vasenkov, Sergey, e Pavel Kortunov. "PFG NMR measurements of tortuosity factors for diffusion in meso- and macropores of FCC catalysts". Diffusion fundamentals 1 (2005) 2, S. 1-11, 2005. https://ul.qucosa.de/id/qucosa%3A14484.

Testo completo
Abstract (sommario):
Pulsed field gradient (PFG) NMR is applied to measure self-diffusion coefficients of 1,3,5 tri-isopropyl-benzene in the particles of several industrial FCC catalysts having different systems of meso- and macropores. Relating these diffusivities to the self-diffusion coefficient of 1,3,5 tri-isopropyl-benzene in the liquid phase, the tortuosity factors for diffusion in the meso- and macropores of the particles were obtained. The values of the tortuosity factors were found to increase with a increasing volumetric fraction of the small (< 20 nm) meso- and macropores in the total intraparticle volume.
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46

Abdallah, Adel. "Modélisation de l'infiltration dans les sols fins compactés : intégration des écoulements préférentiels dans les macropores". Vandoeuvre-les-Nancy, INPL, 1999. http://docnum.univ-lorraine.fr/public/INPL_T_1999_ABDALLAH_A.pdf.

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Afin d'étudier l'intégration des écoulements préférentiels à travers les macropores observés dans les sols fins compactés, 3 approches de modélisation différentes sont développées. La première est celle d'un milieu homogène dont les propriétés hydrodynamiques sont décrites par la formulation de Van Genuchten & Mualem. La deuxième est basée sur le concept de la double porosité où la matrice du sol et les macropores sont traités comme deux domaines d'écoulement présentant des propriétés hydrauliques différentes, et un terme d'échange décrit leur interaction. La troisième suppose que la distribution dimensionnelle de la porosité du sol et par conséquent, les courbes de rétention et de conductivité hydraulique suivent des lois bimodales également décrites par la formulation de Van Genuchten & Mualem. Pour chacune de ces approches, un modèle direct simulant l'infiltration verticale et une procédure d'identification des paramètres par la méthode inverse sont présentés. Les résultats des simulations d'essais d'infiltration au laboratoire sont confrontés aux données expérimentales. Il en ressort que le concept de la double porosité, bien qu'il fournisse une description plus réaliste du processus d'infiltration dans les sols macroporeux, montre ses limites d'applicabilité étant donné que l'estimation de ses paramètres s'avère complexe. Les approches plus pragmatiques, basées sur l'intégration de l'effet hydraulique des macropores dans les propriétés hydrodynamiques du sol à travers les lois unimodale et bimodale, se sont montrées plus intéressantes. Les résultats de l'estimation des paramètres pour ces 2 approches, suggèrent que la distribution dimensionnelle des pores dans les sols fins compactés, varie entre les lois unimodale et bimodale et ce, en fonction de la teneur en eau et du mode de compactage
In order to investigate the integration of preferential flow through macropores observed in compacted fine-textured soils, 3 different modeling approaches are developed. The first considers a homogeneous medium whose hydraulic properties are described by the Van Genuchten & Mualem' s formulation. The second is based on the double-porosity concept where the soil matrix and the macropores are treated as two different flow-domains presenting different hydraulic parameters and an exchange equation takes into account the interaction mechanism. The third assumes that the pore-size distribution and consequently, the water retention and hydraulic conductivity curves follow bimodal laws also described by Van Genuchten & Mualem's formulation. For each one of these approaches, a direct model simulating the vertical infiltration and an inverse procedure for parameter estimation are presented. The simulations of laboratory infiltration tests are confronted with the experimental data. This reveals that the double-porosity concept, while providing a more realistic description of the infiltration process in macroporous soils, is limited in practice, since the two-domain parameters estimation is shown to be complex. The more pragmatic approaches based on the integration of macropores effect in the soil hydraulic properties through unimodal and bimodal functions are shown to be more interesting. The parameter estimates obtained for these 2 approaches suggest that the pore-size distribution of compacted fine-textured soils varies between unimodal and bimodal laws depending on initial water-content and compaction procedure
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47

Dodt, William G. "On the evolution of kangaroos and their kin (family Macropodidae) using retrotransposons, nuclear genes and whole mitochondrial genomes". Thesis, Queensland University of Technology, 2018. https://eprints.qut.edu.au/116286/1/William_Dodt_Thesis.pdf.

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Despite extensive investigation, a complete understanding of the evolutionary history of the Macropodidae (kangaroos and their kin) has remained elusive. This research has utilized DNA sequences and retrotransposons (genes that jump around within the genome) to shed light on the evolutionary timing and dynamics of these iconic marsupials over the past 20 million years, and draw correlations with past climate change events. The research shows that these marsupials underwent a rapid radiation, diversifying into a wide array of forms, coincident with a trend of climatic cooling and drying over the past ~8 million years.
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48

Ramsey, David. "Feeding strategies and habitat utilisation of insular populations of the agile wallaby (Macropolis agilis) and the swamp wallaby (Wallabia bicolor): Implications for management of a coastal ecosystem on South Stradbroke Island, Queensland". Thesis, Queensland University of Technology, 1996. https://eprints.qut.edu.au/105697/1/T%28S%29%20116%20Feeding%20strategies%20and%20habitat%20utilisation%20of%20insular%20populations%20of%20the%20agile%20wallaby%20%28Macropus%20agilis%29%20and%20the%20swamp%20wallaby%20%28Wallabia%20b.pdf.

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The feeding strategies and habitat utilisation of agile wallabies (Macropus agilis) and swamp wallabies ( Wallabia bicolo() were studied on South Stradbroke Island in Moreton Bay, Queensland. Utilisation of foredunes on the island was chiefly by agile wallabies with higher utilisation recorded on the more lush spinifex grass on the primary dune. The extent of grazing on the foredunes along the island was dependent on a number of factors, especially vegetation composition and abundance of grasses in habitats adjacent to the foredunes. In addition, higher feeding activity by both species of wallaby were found on more abundant areas of foredune. Grazing impact on the principal foredune stabilising species, sand spinifex grass ( Spinifex sericeus) was minimal. However, grazing resulted in a decreased abundance of other sand stabilising species on the foredune and could result in decreased species diversity.
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49

Pechenik, Natalie. "Lateral macropore dominated flow on a clay settling area in the phosphate mining district, peninsular Florida". [Tampa, Fla] : University of South Florida, 2009. http://purl.fcla.edu/usf/dc/et/SFE0002982.

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50

Roure, EC. "Flexibility in antipredator behaviour of Tasmanian macropods to altered devil abundance". Thesis, 2019. https://eprints.utas.edu.au/34775/1/Roure_whole_thesis.pdf.

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Trophic cascades have been occurring at an increased rate due to the global decline of top predators. Top predators are important in maintaining the biodiversity of ecosystems through their top-down influence on prey species, both consumptive via predation which affects population vital rates and behavioural in response to the risk of predation. Predator presence and density is known to have strong influence on prey behaviour and demographics. Antipredator, or risk-sensitive, behaviours of prey individuals reflect their perceived level of threat in the environment. Behavioural responses in prey to changes in predator abundance, either declines or increases, can happen after a relatively short periods exposure (weeks or months). However, the expression of such behaviours will vary between species and individuals, depending on factors such as ecological niche, body-size and age. The flexibility of prey behaviour can therefore indicate the perceived level of risk, predator-induced or otherwise, in the environment. A rare opportunity to study the simultaneous effects of top predator decline and increase is afforded by the natural decline of the Tasmanian devil (Sarcophilus harrisii) from a novel infectious disease across its distributional range in Tasmania, Australia, and an assisted translocation for conservation of the devil to an offshore island. Tasmanian devils have drastically declined in abundance in the past two decades due to the transmissible devil facial tumour disease, with some areas of the state reduced to only 5% of the original devil population. Devil decline has already begun to have an impact on the behaviour of prey species in the environment but is likely to cause greater effects to the ecosystem balance as the disease continues to spread across Tasmania. To provide a wild-living insurance population, in the event of extinction of the devil in the wild, a disease-free population of devils was introduced onto Maria Island, a historically devil-free island and National Park 5km off the east coast of Tasmania. To determine the influence of devil abundance on Tasmanian macropod antipredator behaviours, three types of antipredator behaviour were studied (vigilance behaviour, flight initiation distance and emergence time and distance from cover) following the loss and gain in abundance of devils. The three species studied, the Tasmanian pademelon (Thylogale billardierii), Bennett’s wallaby (Macropus rufogriseus) and Forester kangaroo (Macropus giganteus tasmaniensis), are all susceptible to predation from Tasmanian devils, but due to species differences will express different levels of risk-sensitive behaviours. Macropod behaviours were compared at three sites with distinct devil abundances using both historic and novel data sets collected ‘before’ and ‘after’ changes in Tasmanian devil abundance. Top predator pressure proved to have little influence on the expression of antipredator behaviours in macropods. No universal changes were seen among all species in response to devil decline or increase over time. However, changes in the structural complexity of the environment (vegetation regrowth) had a strong influence on risk-sensitive behaviour, irrespective of devil abundance. Species ecology, body size (between species and within species) and age also influenced the expression of antipredator behaviours of macropods. Smaller prey animals (both due to species body size and age) are most vulnerable to predation. This vulnerability was reflected in their anti-predator behaviour which did not reflect changes in predator pressure. Larger species are more influenced by vegetation changes than predator abundance changes. These results illustrate the complex and multifaceted relationship between predator and prey and the need for more comprehensive studies on interspecies relationships to prevent further loss of top predators in the natural environment.
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