70 resultados para niche.


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Variations in environmental parameters (e. g. temperature) that form part of global climate change have been associated with shifts in the timing of seasonal events for a broad range of organisms. Most studies evaluating such phenological shifts of individual taxa have focused on a limited number of locations, making it difficult to assess how such shifts vary regionally across a species range. Here, by using 1445 records of the date of first nesting for loggerhead sea turtles (Caretta caretta) at different breeding sites, on different continents and in different years across a broad latitudinal range (25-39 degrees ' N), we demonstrate that the gradient of the relationship between temperature and the date of first breeding is steeper at higher latitudes, i.e. the phenological responses to temperature appear strongest at the poleward range limit. These findings support the hypothesis that biological changes in response to climate change will be most acute at the poleward range limits and are in accordance with the predictions of MacArthur's hypothesis that poleward range limit for species range is environmentally limited. Our findings imply that the poleward populations of loggerheads are more sensitive to climate variations and thus they might display the impacts of climate change sooner and more prominently.

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Melbourne is the second largest city in Australia with a diverse, multilayered society that reflects its rich musical life. There are many community choirs formed by various cultural and linguistically diverse groups. This paper is part of an ongoing project, well-being and ageing: community, diversity and the arts (since 2008), undertaken by Deakin University and Monash University, that explores the cultural diversity within Australian society and how active music engagement fosters well-being.

The singing groups selected for this discussion are the Skylarkers, the Bosnian Behar Choir, and the Coro Furlan. The Skylarkers and the Bosnian Behar Choir are mixed groups who who respectively perform popular music from their generation and celebrate their culture through music. The Coro Furlan is an Italian male choir who understand themselves as custodians of their heritage.

In these interpretative, qualitative case studies semi-structured interviews were undertaken and analyzed using Interpretative Phenomenological Analysis. In this approach there is an exploration of participants’ understanding of their lived experiences.

The analysis of the combined data identified musical and social benefits that contribute to participants’ sustained well-being. Musical benefits occurred through sharing, learning and singing together. Social benefits included opportunities to build friendships, overcome isolation and gain a sense of validation. Many found that singing enhanced their health and happiness. Active music making in community choirs continues to be an effective way to build community, and cognitive, affective and physical well-being.

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Animals respond to environmental variation by exhibiting a number of different behaviours and/or rates of activity, which result in corresponding variation in energy expenditure. Successful animals generally maximize efficiency or rate of energy gain through foraging. Quantification of all features that modulate energy expenditure can theoretically be modelled as an animal energetic niche or power envelope; with total power being represented by the vertical axis and n-dimensional horizontal axes representing extents of processes that affect energy expenditure. Such an energetic niche could be used to assess the energetic consequences of animals adopting particular behaviours under various environmental conditions. This value of this approach was tested by constructing a simple mechanistic energetics model based on data collected from recording devices deployed on 41 free-living Magellanic penguins (Spheniscus magellanicus), foraging from four different colonies in Argentina and consequently catching four different types of prey. Energy expenditure was calculated as a function of total distance swum underwater (horizontal axis 1) and maximum depth reached (horizontal axis 2). The resultant power envelope was invariant, irrespective of colony location, but penguins from the different colonies tended to use different areas of the envelope. The different colony solutions appeared to represent particular behavioural options for exploiting the available prey and demonstrate how penguins respond to environmental circumstance (prey distribution), the energetic consequences that this has for them, and how this affects the balance of energy acquisition through foraging and expenditure strategy.

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In the face of the physical and physiological challenges of performing breath-hold deep dives, marine vertebrates have evolved different strategies. Although behavioural strategies in marine mammals and seabirds have been investigated in detail, little is known about the deepest-diving reptile – the leatherback turtle (Dermochelys coriacea). Here, we deployed tri-axial accelerometers on female leatherbacks nesting on St Croix, US Virgin Islands, to explore their diving strategy. Our results show a consistent behavioural pattern within dives among individuals, with an initial period of active swimming at relatively steep descent angles (∼–40 deg), with a stroke frequency of 0.32 Hz, followed by a gliding phase. The depth at which the gliding phase began increased with the maximum depth of the dives. In addition, descent body angles and vertical velocities were higher during deeper dives. Leatherbacks might thus regulate their inspired air-volume according to the intended dive depth, similar to hard-shelled turtles and penguins. During the ascent, turtles actively swam with a stroke frequency of 0.30 Hz but with a low vertical velocity (∼0.40 ms–1) and a low pitch angle (∼+26 deg). Turtles might avoid succumbing to decompression sickness (‘the bends’) by ascending slowly to the surface. In addition, we suggest that the low body temperature of this marine ectotherm compared with that of endotherms might help reduce the risk of bubble formation by increasing the solubility of nitrogen in the blood. This physiological advantage, coupled with several behavioural and physical adaptations, might explain the particular ecological niche the leatherback turtle occupies among marine reptiles.

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Optimal foraging models predict that large predators should concentrate on large prey in order to maximize their net gain of energy intake. Here, we show that the largest species of sea turtle, Dermochelys coriacea, does not strictly adhere to this general pattern. Field observations combined with a theoretical model suggest that a 300 kg leatherback turtle would meet its energetic requirements by feeding for 3–4 h a day on 4 g jellyfish, but only if prey were aggregated in high-density patches. Therefore, prey abundance rather than prey size may, in some cases, be the overriding parameter for foraging leatherbacks. This is a classic example where the presence of small prey in the diet of a large marine predator may reflect profitable foraging decisions if the relatively low energy intake per small individual prey is offset by high encounter rates and minimal capture and handling costs. This study provides, to our knowledge, the first quantitative estimates of intake rate for this species.

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Today, designers use a diverse range of alternative media to have a more efficient form of communication. This research is to investigate the potential of traditionally-inspired contemporary communication design to bridge cultural understandings between and among Malaysians of diverse racial and ethnic backgrounds. Specifically, I propose to design a new signage system in the Mah Meri indigenous community in Malaysia. This is in view that despite the development of the latest media alternatives in use today, the Mah Meri community still lags behind in terms of utilization of these new communication facilities. This project aims to improve social interactions between this community and visitors. The signage system that I propose will help outsiders to navigate in and around the Mah Meri settlements easier and faster because the system provides relevant information in a simple and easy to understand method. Without this signage system visitors will have difficulty in finding the right directions. This work also endeavours, through the notion of creating a new signage system to enrich the cultural identity of the Mah Meri community based on their beliefs in the elements of nature. This, in turn, will create a niche for the community to promote the uniqueness of their culture and identity to outsiders.

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The Australian goat meat industry has mostly processed feral goats for export. As goat meat markets mature there will be an increased demand for farmed goats to meet supply, especially into niche markets. Production benchmarking showed that Victorian commercial goat meat producers are located generally in areas with <500 mm rainfall, usually in conjunction with other livestock and cropping enterprises. On average, 67% of farm area, equal to 701 ha (range 55 – 4400 ha) was allocated to the goat enterprise. Commercial producers used Boer bucks, at an average mating rate of 2.2%, over Boer X or feral X does. Weaning rates averaged 99% (range 51 - 165%). There was a large range in husbandry ($0 - $3.07) and supplementary feeding ($6.75 - $9.60) expenditure. Fifty percent of producers indicated that they carried out regular faecal egg counts to assess worm burdens. Seasonal supply patterns showed that producers were supplying Christmas and Easter markets with a live weight range of 12 - 40 kg and an overall average live weight of 26 kg. The issues of concern identified by commercial growers were: internal parasitism, doe fertility, kid predation, kid growth rates, Johnes disease, and fencing security. This study indicated that there is considerable scope to improve the productivity of the Victorian commercial goat meat industry. Most producers supply smaller carcases on a strong seasonal basis. This supply pattern inhibits industry development.

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The Victorian goat meat industry is a significant contributor to export earnings, which is derived largely from the harvest of feral goats. The potential for exports of farmed goat meat into Asian product markets is being developed in a supply chain approach with producers, processors, exporters and Asian importers. Producers have been networked in four locations to improve supply capability and participate in production and economic benchmarking. In the absence of an existing market for premium farmed goat meat, a larger group of producers are cooperating with a marketer to develop a niche market in the Asian food service sector. This presents a challenge to the group in developing commercial relationships and playing a role in the marketing of their goat meat.

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Nanomaterials are rich in potential, particularly for the formation of scaffolds that mimic the landscape of the host environment of the cell. This niche arises from the spatial organization of a series of biochemical and biomechanical signals. Self-assembling peptides have emerged as an important tool in the development of functional (bio-)nanomaterials; these simple, easily synthesized subunits form structures which present the properties of these larger, more complex systems. Scaffolds based upon these nanofibrous matrices are promising materials for regenerative medicine as part of a new methodology in scaffold design where a "bottom-up" approach is used in order to simulate the native cellular milieu. Importantly, SAPs hold the potential to be bioactive through the presentation of biochemical and biomechanical signals in a context similar to the natural extracellular matrix, making them ideal targets for providing structural and chemical support in a cellular context. Here, we discuss a new methodology for the presentation of biologically relevant epitopes through their effective presentation on the surface of the nanofibers. Here, we demonstrate that these signals have a direct effect on the viability of cells within a three-dimensional matrix as compared with an unfunctionalized, yet mechanically and morphologically similar system. © 2014 Wiley Periodicals, Inc. Biopolymers (Pept Sci) 102: 197-205, 2014.

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Dive duration generally increases with body size in animals including wildfowl. Therefore, diving behaviour may vary between the sexes in sexually size dimorphic species, such as the extremely sexually size dimorphic Musk Duck Biziura lobata. However, a previous study reports longer dives in the smaller sex (females) when breeding. In this study, non-breeding male Musk Ducks dived for significantly longer periods than females and tended to have longer inter-dive intervals, conforming to the general patterns described for other species. The differences in dive behaviour we describe may be explained by niche partitioning or differential oxygen requirements or uptake rates by the sexes.

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 The wide need for sewage treatment facilities at the township level across China implies an emerging niche market for water and sanitation developers, investors and financiers. However this potential market is difficult to enter with traditional financing and delivery methods, because township sewage features small amount, volatile quantity, geographically scattering, immature fee charging system, weak affordability, and lack of capacities. A group of concession sewage treatment projects collectively implemented by a private company in the Changsha County of Hunan Province under the so called ‘Changsha Model’ provided innovative solutions. This cases study first examined the portfolio approach in terms of multiple delivery method integration, technology, and centralized control system, and evaluated the replicability of the new model. Practices and lessons learned from the case were then presented and summarized that can be applied to the following township sewage treatment facility development. Last, the Changsha Model was compared with similar infrastructure portfolio delivery solutions applied in the US.

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Umbilical cord blood (UCB) is one of the richest sources for hematopoietic stem/progenitor cells (HSPCs), with more than 3000 transplantations performed each year for the treatment of leukemia and other bone marrow, immunological, and hereditary diseases. However, transplantation of single cord blood units is mostly restricted to children, due to the limited number of HSPC per unit. This unit develops a method to increase the number of HSPCs in laboratory conditions by using cell-free matrices from bone marrow cells that mimic 'human-body niche-like' conditions as biological scaffolds to support the ex vivo expansion of HSPCs. In this unit, we describe protocols for the isolation and characterization of HSPCs from UCB and their serum-free expansion on decellularized matrices. This method may also help to provide understanding of the biochemical organization of hematopoietic niches and lead to suggestions regarding the design of tissue engineering-based biomimetic scaffolds for HSPC expansion for clinical applications.

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Whichever way you look at it, online crowdfunding is ramifying. From its foundations supporting creative industry initiatives, crowdfunding has branched into almost every aspect of public and private enterprise. Niche crowdfunding platforms and models are burgeoning across the globe faster than you can trill “kerching”. Early adopters have been quick to discover that in addition to money, they also get free market information and an opportunity to develop a relationship with their market base. Despite these evident benefits, universities have been cautious entrants in the crowdfunding space and more generally in the emerging ‘collaborative economy’ (Owyang, 2013). There are many cultural and institutional legacies that might explain this reluctance. For example, to date universities have achieved social (and economic) distinction through refining a set of exclusionary practices including, but not limited to, versions of gatekeeping, ranking and credentialing. These practices are reproduced in the expected behaviors of individual academics who garner social currency and status as experts, legislators and interpreters (Osborne, 20014: 435). Digitalization and the emergent knowledge and collaboration economies, have the potential to disrupt the academy’s traditional appeals to distinction and to re-engage universities and academics with their public stakeholders. This chapter will examine some of the challenges and benefits arising from public micro-funding of university-based research initiatives during a period of industrial transition in the university sector.Broadly then this chapter asks; what does scholarship mean in a digital ecosystem where sociality (rather than traditional systems for assessing academic merit) affords research opportunity and success? How might university research be rethought in a networked world where personal and professional identities are blurred? What happens when scholars adopt the same pathways as non-scholars for knowledge discovery, development and dissemination through use of emerging practices such as crowdfunding. These issues will be discussed through detailed exploration of a successful pilot project to crowdfund university research; Research My World. This project, a collaboration between Deakin University and the crowdfunding platform pozible.com, set out to secure new sources of funding for the ‘long-tail’ of academic research. More generally, it aimed to improve the digital capacity of the participating researchers and create new opportunities for public engagement for the researchers themselves as well as the university. We will examine how crowdfunding and social media platforms alter academic effort (the dis-intermediation or re-intermediation of research funding, reduction of the compliance burden, opportunities for market validation and so on), as well as the particular workflows of scholarly researchers themselves (improvements in “digital presence-building”, provision of cheap alternative funding, opportunities to crowdsource non-academic knowledge). In addressing these questions, this chapter will explore the influence that crowdfunding campaigns have for transforming contemporary academic practices across a range of disciplinary instances, providing the basis for a new form of engagement-led research. To support our analysis we will provide an overview of the initiative through quantitative analysis of a dataset generated by the first iteration of Research My World projects.