579 research outputs found

    Wanted Dead or Alive? The Relative Value of Reef Sharks as a Fishery and an Ecotourism Asset in Palau

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    Over the last 20 years, ecotourism to view and interact with marine megafauna has become increasingly popular (Higham and Lück 2008). Examples of this type of tourism include turtle and whale watching, snorkelling with seals and shark diving (Jacobson and Robles 1992; Anderson and Ahmed 1993; Orams 2002; Kirkwood et al. 2003; Dearden et al. 2008; Dicken and Hosking 2009). The occurrence of many aggregations of megafauna along the coasts of regional areas remote from centres of population means that such tourism also provides significant flow-on effects and diversification to local economies where few alternative sources of income exist (Milne 1990; Garrod and Wilson 2004). Importantly, the development of a well-managed ecotourism industry based on megafauna provides the opportunity for local people to utilise natural resources in a sustainable manner over the long-term (Mau 2008). The economic value of tourism based on marine megafauna is enormous. In 2008, a study of whale watching estimated that this form of tourism was available in 119 countries, involved approximately 13 million participants and generated an income to operators and supporting businesses (hotels, restaurants and souvenirs) of over US2.1billion(OConnoretal.2009).ThisindustryisestimatedtohavethepotentialtogenerateannualrevenuesofoverUS2.1 billion (O'Connor et al. 2009). This industry is estimated to have the potential to generate annual revenues of over US2.5 billion (Cisneros-Montemayor et al. 2010). The development of whale watching has been paralleled by growth in tourism based on other types of marine megafauna. In particular, tourism to observe sharks and rays has become increasingly common. At the forefront of this relatively new market are industries that focus on whale sharks (Rhincodon typus) with estimates calculated in 2004 suggesting that these generated more than US$47.5 million worldwide, providing important revenues to developing countries such as Ecuador, Thailand and Mozambique (Graham 2004). Diving with other species of sharks has followed a similar trend of growing popularity. In 2005, it was estimated that approximately 500,000 divers were engaged in shark-diving activities worldwide (Topelko and Dearden 2005). An increasing range of opportunities for this type of tourism are available, including cage diving, shark feeding and drift diving with reef and oceanic sharks. Shark-diving tourism can be found in more than 40 countries (Carwardine and Watterson 2002), with new destinations and target species being established rapidly, due to the increasing recognition of the economic potential of this activity (Dicken and Hosking 2009; De la Cruz Modino et al. 2010)

    The Socio-Economic Value of the Shark-Diving Industry in Fiji

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    Based on a survey of divers, dive operators, resort managers, estimates business revenues from shark diving and related expenditures by area; tax revenues; and economic benefit to local communities

    Two's Company, Three's a Crowd: Experimental Evaluation of the Evolutionary Maintenance of Trioecy in Mercurialis annua (Euphorbiaceae)

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    Trioecy is an uncommon sexual system in which males, females, and hermaphrodites co-occur as three clearly different gender classes. The evolutionary stability of trioecy is unclear, but would depend on factors such as hermaphroditic sex allocation and rates of outcrossing vs. selfing. Here, trioecious populations of Mercurialis annua are described for the first time. We examined the frequencies of females, males and hermaphrodites across ten natural populations and evaluated the association between the frequency of females and plant densities. Previous studies have shown that selfing rates in this species are density-dependent and are reduced in the presence of males, which produce substantially more pollen than hermaphrodites. Accordingly, we examined the evolutionary stability of trioecy using an experiment in which we (a) indirectly manipulated selfing rates by altering plant densities and the frequency of males in a fully factorial manner across 20 experimental plots and (b) examined the effect of these manipulations on the frequency of the three sex phenotypes in the next generation of plants. In the parental generation, we measured the seed and pollen allocations of hermaphrodites and compared them with allocations by unisexual plants. In natural populations, females occurred at higher frequencies in denser patches, a finding consistent with our expectations. Under our experimental conditions, however, no combination of plant densities and male frequencies was associated with increased frequencies of females. Our results suggest that the factors that regulate female frequencies in trioecious populations of M. annua are independent of those regulating male frequencies (density), and that the stable co-existence of all three sex phenotypes within populations is unlikely

    Application of OCT to examination of easel paintings

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    We present results of applying low coherence interferometry to gallery paintings. Infrared low coherence interferometry is capable of non-destructive examination of paintings in 3D, which shows not only the structure of the varnish layer but also the paint layers

    Size and Content of the Sex-Determining Region of the Y Chromosome in Dioecious <i>Mercurialis annua</i>, a Plant with Homomorphic Sex Chromosomes.

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    Dioecious plants vary in whether their sex chromosomes are heteromorphic or homomorphic, but even homomorphic sex chromosomes may show divergence between homologues in the non-recombining, sex-determining region (SDR). Very little is known about the SDR of these species, which might represent particularly early stages of sex-chromosome evolution. Here, we assess the size and content of the SDR of the diploid dioecious herb &lt;i&gt;Mercurialis annua&lt;/i&gt; , a species with homomorphic sex chromosomes and mild Y-chromosome degeneration. We used RNA sequencing (RNAseq) to identify new Y-linked markers for &lt;i&gt;M. annua.&lt;/i&gt; Twelve of 24 transcripts showing male-specific expression in a previous experiment could be amplified by polymerase chain reaction (PCR) only from males, and are thus likely to be Y-linked. Analysis of genome-capture data from multiple populations of &lt;i&gt;M. annua&lt;/i&gt; pointed to an additional six male-limited (and thus Y-linked) sequences. We used these markers to identify and sequence 17 sex-linked bacterial artificial chromosomes (BACs), which form 11 groups of non-overlapping sequences, covering a total sequence length of about 1.5 Mb. Content analysis of this region suggests that it is enriched for repeats, has low gene density, and contains few candidate sex-determining genes. The BACs map to a subset of the sex-linked region of the genetic map, which we estimate to be at least 14.5 Mb. This is substantially larger than estimates for other dioecious plants with homomorphic sex chromosomes, both in absolute terms and relative to their genome sizes. Our data provide a rare, high-resolution view of the homomorphic Y chromosome of a dioecious plant

    Housing options for older people in a reimagined housing system: a case study from England

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    The housing options of older people now extend far beyond the traditional choice between staying put and making do, or moving to specialist housing or residential care. A flexible suite of options has emerged, centred on promoting independence and wellbeing. Valuable insights have been provided into the development, delivery, costs and benefits of these options. Light has also been cast on the experiences and preferences of older people. However, little is know about who gets what housing, where and why. This reflects a tendency within analysis to consider these different housing options in isolation. This study responds by situating the housing options of older people within wider debates about the reimagining of the housing system driven by the neoliberal transformation in housing politics. Taking a case study approach, it explores the gap between the ambitions of policy and realities of provision at the local level, relates this to the particular intersection of state practices and market mechanisms manifest in the case study and, in doing so, rises to the challenge of extending analysis of the impacts of the neoliberal approach on the right to housing to new groups and different settings

    Probation staff experiences of managing suicidal and self-harming service users

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    The current study sought to explore the impact of suicidal behaviours on probation staff, in relation to their experiences of working with Probation service users who have carried out suicide, attempted suicide or self-harm. Thirteen in-depth interviews were carried out with probation staff who had direct contact with Probation service users in one Probation area, and had varying degrees of experience of managing suicidal or self-injurious service users. These were analysed using Thematic Analysis and five themes were identified. Findings indicate that staff felt that suicide and self-harm by service users are serious issues which need to be recognised and dealt with in an effective yet compassionate manner. However not attending the Suicide Prevention Training or lack of experience was perceived as restricting their ability to know how to deal with these individuals, and offer support. Furthermore, staff were emotionally affected by these incidents and it is recommend that they should continue to be provided with access to appropriate support services after an incident

    Macroalgae Decrease Growth and Alter Microbial Community Structure of the Reef-Building Coral, Porites astreoides

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    This is the publisher’s final pdf. The published article is copyrighted by the Public Library of Science and can be found at: http://www.plosone.org/home.action.With the continued and unprecedented decline of coral reefs worldwide, evaluating the factors that contribute to coral demise is of critical importance. As coral cover declines, macroalgae are becoming more common on tropical reefs. Interactions between these macroalgae and corals may alter the coral microbiome, which is thought to play an important role in colony health and survival. Together, such changes in benthic macroalgae and in the coral microbiome may result in a feedback mechanism that contributes to additional coral cover loss. To determine if macroalgae alter the coral microbiome, we conducted a field-based experiment in which the coral Porites astreoides was placed in competition with five species of macroalgae. Macroalgal contact increased variance in the coral-associated microbial community, and two algal species significantly altered microbial community composition. All macroalgae caused the disappearance of a γ-proteobacterium previously hypothesized to be an important mutualist of P. astreoides. Macroalgal contact also triggered: 1) increases or 2) decreases in microbial taxa already present in corals, 3) establishment of new taxa to the coral microbiome, and 4) vectoring and growth of microbial taxa from the macroalgae to the coral. Furthermore, macroalgal competition decreased coral growth rates by an average of 36.8%. Overall, this study found that competition between corals and certain species of macroalgae leads to an altered coral microbiome, providing a potential mechanism by which macroalgae-coral interactions reduce coral health and lead to coral loss on impacted reefs

    Mutant Prourokinase with Adjunctive C1-Inhibitor Is an Effective and Safer Alternative to tPA in Rat Stroke

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    A single-site mutant (M5) of native urokinase plasminogen activator (prouPA) induces effective thrombolysis in dogs with venous or arterial thrombosis with a reduction in bleeding complications compared to tPA. This effect, related to inhibition of two-chain M5 (tcM5) by plasma C1-inhibitor (C1I), thereby preventing non-specific plasmin generation, was augmented by the addition of exogenous C1I to plasma in vitro. In the present study, tPA, M5 or placebo +/− C1I were administered in two rat stroke models. In Part-I, permanent MCA occlusion was used to evaluate intracranial hemorrhage (ICH) by the thrombolytic regimens. In Part II, thromboembolic occlusion was used with thrombolysis administered 2 h later. Infarct and edema volumes, and ICH were determined at 24 h, and neuroscore pre (2 h) and post (24 h) treatment. In Part I, fatal ICH occurred in 57% of tPA and 75% of M5 rats. Adjunctive C1I reduced this to 25% and 17% respectively. Similarly, semiquantitation of ICH by neuropathological examination showed significantly less ICH in rats given adjunctive C1I compared with tPA or M5 alone. In Part-II, tPA, M5, and M5+C1I induced comparable ischemic volume reductions (>55%) compared with the saline or C1I controls, indicating the three treatments had a similar fibrinolytic effect. ICH was seen in 40% of tPA and 50% of M5 rats, with 1 death in the latter. Only 17% of the M5+C1I rats showed ICH, and the bleeding score in this group was significantly less than that in either the tPA or M5 group. The M5+C1I group had the best Benefit Index, calculated by dividing percent brain salvaged by the ICH visual score in each group. In conclusion, adjunctive C1I inhibited bleeding by M5, induced significant neuroscore improvement and had the best Benefit Index. The C1I did not compromise fibrinolysis by M5 in contrast with tPA, consistent with previous in vitro findings
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