23 resultados para Mus

em Deakin Research Online - Australia


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Whilst there is good evidence for negative impacts of introduced rat species on island ecosystems, the effects of house mice (Mus musculus) are generally less well documented. In some situations, introduced house mice can exert severe impacts, particularly where this is the only introduced mammal. Here, we examine the distribution, relative abundance and breeding success of small burrowing seabirds on Steeple Jason Island, Falklands, in relation to habitat types and the distribution of house mice which is the sole introduced mammal species, and we make comparisons with seabird distribution and densities on the neighbouring island of Grand Jason where mice are absent. Grey-backed storm-petrel (Garrodia nereis) and Wilson's storm-petrel (Oceanites oceanicus), which due to their extremely small size are likely to be the most vulnerable to mouse predation, were considerably more abundant on mouse-free Grand Jason than on Steeple Jason. Grey-backed storm-petrel, which are typically associated with tussac grass, avoided this habitat on Steeple Jason where it is associated with high levels of house mouse activity (assessed from the proportion of wax baits gnawed overnight), whereas on mouse-free Grand Jason, there was no such avoidance. Wilson's storm-petrel nesting on Steeple Jason suffered high rates of egg and chick loss. Whilst we found evidence for detrimental impacts of house mice on the two small storm-petrel species, there was no relationship between relative mouse activity levels and the distribution or abundance of the larger thin-billed Prion (Pachyptila belcheri). © 2014 Springer-Verlag Berlin Heidelberg.

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Management of powerline corridors in Australia has traditionally focused on the complete removal of vegetation using short rotation times owing to the perceived hazard of fire associated with corridor vegetation. Because of the intense management associated with fire hazards, little thought has been given to use of powerline corridors by wildlife. This has resulted in corridors traditionally being viewed as a source of fragmentation and habitat loss within forested ecosystems. We investigated the responses of small mammal communities living in a powerline corridor to management-induced vegetation changes at different successional stages, to determine whether a compromise could be reached between managing corridors for fire and biodiversity. Habitat modelling in the corridor and adjacent forest for three native and one introduced small mammal species demonstrated that species responded to changes in vegetation structural complexity, rather than time-since-management per se. Early seral stages of vegetation recovery after corridor management encouraged the introduced house mouse (Mus domesticus) into corridors and contributed little to biodiversity. Mid-seral-stage vegetation, however, provided habitat for native species that were rare in adjacent forest habitats. As the structural complexity of the vegetation increased, the small mammal community became similar to that of the forest so that corridor vegetation contributed fewer biodiversity benefits while posing an unacceptable fire risk. If ecologically sensitive management regimes are implemented to encourage mid-seral vegetation and avoid complete vegetation removal, powerline corridors have the potential to improve biodiversity. This would maintain landscape connectivity and provide habitat for native species uncommon in the forest while still limiting fuel loads in the corridor.

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TATA box is one of the most important transcription factor binding sites. But the exact sequences of TATA box are still not very clear yet. In this study, we conducted a dedicated analysis on the frequency distribution of TATA Box and its extension sequences on human promoters. Sixteen TATA elements derived from TATA Box motif, TATAWAWN, were classified into three distribution patterns: peak, bottom-peak and bottom. Fourteen TATA extension sequences (up to two base extensions) were predicted to be the new TATA Box elements because of their high motif factors, which indicate their statistical significance. Statistical analysis on the promoters of mouse, zebrafish and drosophila melanogaster verified seven of these elements. It was also observed that the distribution of TATA elements on the promoters of housekeeping genes are very similar with their distribution on the promoters of tissue specific genes in human.

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The diet of a Southern Boobook Ninox novaeseelandiae in a Box-Ironbark woodland remnant in central Victoria was studied. An analysis of 42.5 pellets found invertebrates to represent 82% of the total prey items, but vertebrates, in the form of the House Mouse Mus domesticus, to represent 88% of the biomass. The proportion of spiders as prey items in the diet in this instance (43%) was significantly higher than in other studies on mainland Australia.

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Most studies of habitat use by small mammals rely on data from trapping grids. Such studies pertain to habitat use by individuals, which may not reflect population-level requirements. To meet the challenge of landscape change, it is important to understand habitat use by populations across large geographic areas. We surveyed small mammals in 48 forest remnants across a 300 km2 study area, to investigate the influence of vegetation heterogeneity on regional distributions. Information-theoretic techniques were used to evaluate models of vegetation associations. Richness of native mammals was influenced by vegetation condition: disturbed sites supported fewer species. Models for individual species showed the agile antechinus, Antechinus agilis, to prefer structurally diverse forest vegetation, the long-nosed potoroo, Potorous tridactylus, to favour mesic shrub communities, the bush rat, Rattus fuscipes, to prefer complex low cover regardless of composition, the swamp rat, Rattus lutreolus, to favour reduced canopy cover, and the house mouse, Mus domesticus, to prefer disturbed vegetation. To satisfy the needs of all native species, a mosaic of natural vegetation is required. Degradation and simplification of forest vegetation have detrimental consequences. These results highlight the need to consider habitat quality, together with more traditional biogeographic variables, when investigating factors influencing patch occupancy by native fauna in modified landscapes.


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Medically unexplained symptoms (MUS) confound physicians, and the incidence and prevalence of these conditions is poorly documented.  This is not least due to the complex nature of MUS and mimicry of morbidity with conditions that have common clinical assessment and treatment modalities, e.g. migraine headaches which stress headaches commonly are misdiagnosed as.  Effective treatment modalities for MUS have been more or less non-existent.  In the following we present a modality for the assessment, diagnosis and treatment of MUS that in our experience leads to cure, at least in better than half of these cases measured in terms of allowing the individual back to work.  These results are at least twice as high as those described hitherto (see below), and yet, our treatment modality is beset with many obstacles, not the least of which is the intrasigence of a system that will not and/or can not understand why this modality is so much better than what they are able to offer.  The most importance obstacle is financing, as this modality requires long term and committed financing to work.  The economic implications of not dealing with these issues are described.

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A small sample of eastern Barn Owl Tyto javanica pellets, from native grasslands on the Patho Plains in northern Victoria in February 2007, contained the remains of 48 prey individuals: 38 Australian Plague Locusts Chortoicetes terminifera, nine house Mice Mus domesticus and one Fat-tailed dunnart Sminthopsis crassicaudata. Such a high proportion of locusts in the eastern Barn Owl's diet is noteworthy, and is discussed in the context of recent locust-spraying operations in the region.

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The use of cameras to monitor wildlife is commonplace; however, little is known of the effectiveness of different camera technologies for the detection of mammals. We compared the detection success of three different camera systems, a passive infrared (IR) system, an active IR and a constant video camera, alongside a trapping grid of Elliott and cage traps to determine their effectiveness at detecting mammals at multiple locations in the Otways National Park, Victoria, Australia (n = 160 events; 40 ± 23 [SD] events per night). Species detected and detection rates differed between methods (χ2 = 57.95, df = 2, p < 0.0001). Only house mice (Mus musculus) were detected by camera and traditional trapping techniques. Camera systems alone detected foxes (Vulpes vulpes) and a koala (Phascolarctos cinereus), while traditional traps captured bush rats (Rattus fuscipes), agile antechinus (Antechinus agilis) and a brush-tailed possum (Trichosurus vulpecula) which were not detected by the camera systems. Assuming that the video camera detected all mammals at the camera trap, the passive IR system detected almost all mammals detected by the video and it detected significantly more species than the active IR system. The choice of method will ultimately depend on the species of interest, logistics and the study site, and may substantially influence the results of a study.

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The relationship of vegetation and disturbance factors to the distribution, abundance and diversity of small mammals in the eastern Otway region, Victoria were investigated. Antechinus stuartii, Rattus fuscipes and Rattus lutreolus were widely distributed and occurred in the majority of the eleven floristic vegetation groups identified. Antechinus minimus, Antechinus swainsonnii and Pseudomys novaehollandiae had restricted distributions and were recorded in only two or three vegetation groups. New information on the distribution of the rare species P. novaehollandiae, was obtained and two floristically rich vegetation groups that it preferred were identified. Species-rich small mammal communities occurred in vegetation communities with high numbers of sclerophyll plant species and high structural diversity. Maximum food resources were considered to be provided in these communities. Local habitat diversity was also correlated with species-richness. Small mammal abundance was maximum in non-sclerophyllous canmunities, where high plant productivity was considered to be important. For the first time, the presence of the plant pathogen Phytophthora cinnamomi was shown to affect small mammals. It was associated with small mammal communities of low species richness and abundance, Recovery of small mammal populations after wildfire was slow until the fourth year. Mus musculus reached peak abundance from 2-3 years and then declined rapidly. P. novaehollandiae was the only native species that achieved maximum abundance early in the succession. A. stuartii, R. fuscipes and R. lutreolus approached maximum abundance in mid-succession, while Isoodon obesulus was a mid- to late-successional species. A. minimus survived the fire, but did not persist after one year. The pattern of succession was influenced by attributes of species, such as survival after fire, their ability to disperse and reproduce.

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Context. Wildfire is a major driver of the structure and function of mallee eucalypt- and spinifex-dominated landscapes. Understanding how fire influences the distribution of biota in these fire-prone environments is essential for effective ecological and conservation-based management.

Aims. We aimed to (1) determine the effects of an extensive wildfire (118 000 ha) on a small mammal community in the mallee shrublands of semiarid Australia and (2) assess the hypothesis that the fire-response patterns of small mammals can be predicted by their life-history characteristics.

Methods. Small-mammal surveys were undertaken concurrently at 26 sites: once before the fire and on four occasions following the fire (including 14 sites that remained unburnt). We documented changes in small-mammal occurrence before and after the fire, and compared burnt and unburnt sites. In addition, key components of vegetation structure were assessed at each site.

Key results. Wildfire had a strong influence on vegetation structure and on the occurrence of small mammals. The mallee ningaui, Ningaui yvonneae, a dasyurid marsupial, showed a marked decline in the immediate post-fire environment, corresponding with a reduction in hummock-grass cover in recently burnt vegetation. Species richness of native small mammals was positively associated with unburnt vegetation, although some species showed no clear response to wildfire.

Conclusions. Our results are consistent with the contention that mammal responses to fire are associated with their known life-history traits. The species most strongly affected by wildfire, N. yvonneae, has the most specific habitat requirements and restricted life history of the small mammals in the study area. The only species positively associated with recently burnt vegetation, the introduced house mouse, Mus domesticus, has a flexible life history and non-specialised resource requirements.

Implications. Maintaining sources for recolonisation after large-scale wildfires will be vital to the conservation of native small mammals in mallee ecosystems.

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The JAK/STAT signaling pathway is essential for myogenic regeneration and is regulated by a diverse range of ligands, including interleukin-6 (IL-6) and platelet-derived growth factor-BB (PDGF-BB). Our aim was to evaluate the responsiveness of IL-6 and PDGF-BB to intense exercise, along with STAT3 activation, before and after 12 weeks of resistance training. In young men, IL-6 and PDGF-BB protein concentrations were quantified in biopsied muscle and increased at 3 h post-exercise (17.5-fold and 3-fold, respectively). The response was unaltered by 12 weeks of training. Similarly, STAT3 phosphorylation was elevated post-exercise (12.5-fold), irrespective of training status, as was the expression of downstream targets c-MYC (8-fold), c-FOS (4.5-fold), and SOCS3 (2.3-fold). Thus, intense exercise transiently increases IL-6 and PDGF-BB proteins, and STAT3 phosphorylation is increased. These responses are preserved after intense exercise. This suggests they are not modified by training and may be an essential component of the adaptive responses to intense exercise.

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Introduction and Methods: This study compared changes in myokine and myogenic genes following resistance exercise (3 sets of 12 repetitions of maximal unilateral knee extension) in 20 elderly men (67.8 ± 1.0 years) and 15 elderly women (67.2 ± 1.5 years). Results: Monocyte chemotactic protein (MCP)-1, macrophage inhibitory protein (MIP)-1β, interleukin (IL)-6 and MyoD mRNA increased significantly (P < 0.05), whereas myogenin and myostatin mRNA decreased significantly after exercise in both groups. Macrophage-1 (Mac-1) and MCP-3 mRNA did not change significantly after exercise in either group. MIP-1β, Mac-1 and myostatin mRNA were significantly higher before and after exercise in men compared with women. In contrast, MCP-3 and myogenin mRNA were significantly higher before and after exercise in the women compared with the men. Conclusions: In elderly individuals, gender influences the mRNA expression of certain myokines and growth factors, both at rest and after resistance exercise. These differences may influence muscle regeneration following muscle injury.

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Invasive rodent species have established on 80% of the world's islands causing significant damage to island environments. Insular ecosystems support proportionally more biodiversity than comparative mainland areas, highlighting them as critical for global biodiversity conservation. Few techniques currently exist to adequately detect, with high confidence, species that are trap-adverse such as the black rat, Rattus rattus, in high conservation priority areas where multiple non-target species persist. This study investigates the effectiveness of camera trapping for monitoring invasive rodents in high conservation areas, and the influence of habitat features and density of colonial-nesting seabirds on rodent relative activity levels to provide insights into their potential impacts. A total of 276 camera sites were established and left in situ for 8 days. Identified species were recorded in discrete 15 min intervals, referred to as 'events'. In total, 19 804 events were recorded. From these, 31 species were identified comprising 25 native species and six introduced. Two introduced rodent species were detected: the black rat (90% of sites), and house mouse Mus musculus (56% of sites). Rodent activity of both black rats and house mice were positively associated with the structural density of habitats. Density of seabird burrows was not strongly associated with relative activity levels of rodents, yet rodents were still present in these areas. Camera trapping enabled a large number of rodents to be detected with confidence in site-specific absences and high resolution to quantify relative activity levels. This method enables detection of multiple species simultaneously with low impact (for both target and non-target individuals); an ideal strategy for monitoring trap-adverse invasive rodents in high conservation areas.

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INTRODUCTION: The short latency stretch reflex (SLR) is well described, but the stimulus that evokes the SLR remains elusive. One hypothesis states that reflex size is proportional to muscle fiber stretch, so in this study we examined the relationship between these 2 parameters in human triceps surae muscles. METHODS: Achilles tendon taps and dorsiflexion stretches with different amplitudes and preactivation torques were applied to 6 participants while electromyography and muscle fascicle length changes were recorded in soleus and medial gastrocnemius (MG). RESULTS: In response to tendon taps, neither fascicle length nor velocity changes were correlated with SLR size in either muscle, but accelerometer peaks were observed immediately after hammer-tendon contact. Similar results were obtained after dorsiflexion stretches. CONCLUSION: Muscle fascicle stretch is poorly correlated with SLR size, regardless of perturbation parameters. We attribute the SLR trigger to the transmission of vibration through the lower limb, rather than muscle fiber stretch. Muscle Nerve, 2015.