357 resultados para plant communities


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It is well established that herbivorous insects respond to changes in plant odour production, but little attention has been given to whether these responses relate to direct fitness costs of plant volatile production on insect growth and survival. Here, we use transgenic Nicotiana tabacum (tobacco) plants that produce relatively large amounts of the volatile (S)-linalool to study whether the responses of egg-laying herbivorous insects to linalool production relate directly to the growth and survival of offspring. In choice tests, fewer eggs were laid on transgenic plants compared with non-transformed controls, indicating that increased linalool emissions have a deterrent effect on Helicoverpa armigera oviposition. Larval survival and larval mass after feeding on transgenic leaves, however, was comparable to non-transformed controls. (S)-linalool, whether in volatile or sequestered form, does not appear to have a direct effect on offspring fitness in this moth. We discuss how the ecology of this polyphagous moth species may necessitate a high tolerance for certain volatiles and their related non-volatile compounds, and suggest that responses by adult female H. armigera moths towards increased linalool production may be context specific and relate to other indirect effects on fitness.

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Plant and machinery valuation is important to every company.s annual financial reporting. It is reported under the non-current assets section, and the valuers are generally employed to provide the up to date valuation of the non-current assets valuation such as property, plant and equipment that can make up to 80% of the total assets of a company. The valuation of plant and machinery is also important for other purposes such as securing loan facilities, sales, takeover, insurance and auction. The application of 2005 International Financial Reporting Standard (IFRS) has a subsequent impact on the financial sector, as a whole. The accountants have to choose between the Historical Cost approach and Market Value approach in determining the value of the client.s assets. In Malaysia, the implementation of IFRS has a domino effect on the financial system, especially for plant and machinery valuation for financial reporting. The comparison data for plant and machinery valuation is limited unlike land and building valuation. The question of Malaysian valuer.s ability to comply with the IFRS standard keeps rising every day, not just to the accountants, but also other related parties such as financial institutions, government agencies and the clients. This is happening because of different interpretations of premise of value for plant and machinery, as well as methods been used and differences in standards of reporting among the valuers conducting plant and machinery valuation. The root of the problem lies in the lack of practical guidelines governing plant and machinery valuation practices and different schools of thought among the valuers. Some follow the United Kingdom.s RICS guidelines, whilst some valuers are more comfortable with the United State.s USPAP rules, especially on the premise of value. This research is to investigate the international best practices of plant and machinery valuation and to establish the common valuation concept, awareness and application of valuation methodology and valuation process for plant and machinery valuation in Malaysia. This research uses a combination of the qualitative and quantitative research approach. In the qualitative approach, the content analyses were conducted from the international practices and current Malaysian implementation of plant and machinery valuation. A survey (quantitative approach) via questionnaire was implemented among the registered and probationary valuers in Malaysia to investigate their understanding and opinion relating to plant and machinery valuation based on the current practices. The significance of this research is the identification of international plant and machinery practices and the understanding of current practices of plant and machinery valuation in Malaysia. It is found that issues embedding plant and machinery valuation practices are limited numbers of resources available either from scholars or practitioner. This is supported by the general finding from the research survey that indicates that there are immediate needs for practical notes or guidelines to be developed and implemented to support the Malaysian valuers practising plant and machinery valuation. This move will lead to a better understanding of plant and machinery valuation, reducing discrepancies in valuation of plant and machinery and increased accuracy among practising valuers.

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Dominant discourses around young people and social networking in the mass media are littered with negative connotations and moral panics. While some scholars challenge this negativity, their focus has predominantly been upon the formation of friendships, the construction of identity and the presentation of the self online. We argue that as well as engaging in such areas, young people are also appropriating social networking sites, such as YouTube, as spaces in which they can engage in what Jean Burgess terms, â˜Vernacular Creativityâ â a way of describing and surfacing creative practices that emerge from non-elite, specific everyday contexts. Using case study material we consider the processes of Vernacular Creativity as engaged with by young people in relation to doing graffiti with YouTube. Through this, and given that graffiti is a cultural practise traditionally associated with physical space, we also consider points of continuity and discontinuity in relation to Vernacular Creativity mediated with YouTube and the significance of such things in enabling young people to connect and create with like-minded others.

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This paper aims to shed light on the planning and development processes of the knowledge-based urban development phenomenon, with respect to the construction of knowledge community precincts. We undertake policy and best practice analyses to learn from the planning and development processes of internationally renowned knowledge community precinctsâfrom Copenhagen, Eindhoven and Singapore. In the light of this, we scrutinise major Australian knowledge community precinct initiativesâfrom Sydney, Melbourne and Brisbaneâto better understand the dynamics of national practices, and benchmark them against the international best practice cases. The paper concludes with a discussion on the study findings and successfully establishing space and place for both knowledge economy and society in Australian cities.

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This chapter describes how investigative journalism can uncover news that often goes unreported about personalities, problems, ways of life and pressing issues in ethnic and religious sub-communities. While investigative journalism is traditionally understood as reporting that exposes corrupt, inefficient, incompetent or other inappropriate conduct in politics and business circles, investigative reporters do far more than that. They also map human activities, landmarks, patterns and changes in the landscape, and connections across the whole of society. This type of investigative journalism can improve reporting of ethnic and religious sub-communities via identification, deep observation and analysis of trends, events, and issues that would otherwise remain hidden or obscured. The chapter includes details of techniques that investigative journalists can employ to identify interesting topics, find sources of information, analyse data and issues, and report compelling stories.

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This article provides a general overview of some of the plant research being conducted by a number of researchers at the Queensland University of Technology (QUT) Brisbane. Details about student projects and research facilities have been limited to those of relevance to plant structure and systematics. Academics, technicians and research students involved in plant research are in the Faculty of Science and Engineering, mainly in the School of Earth, Environment and Biological Sciences (EEBS), with a few exceptions. Our offices and laboratories are housed in a number of different buildings at the Gardens Point campus (e.g., P, Q, R, S, M Blocks) and we have strong collaborative links with Queensland Herbarium (BRI) and Mt Coot-tha Botanic Gardens.

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This paper approaches a particular type of fandom practice, what I am calling fan activism. Fan activism is a topic that has historically received little attention in the fandom studies area. Here, I analyse the #ForaRicardoTeixeira campaign from a sample of 15,000 tweets posted at the time of his re¬signation from CBF. This paper combines quantitative and qualitative methods to investigate a) the com¬munity dynamics and b) the content of the conversations. The dynamics analysis pointed out, for instance, patterns of users and information sources, and the content analysis revealed how users framed the case. Future implications of the results for the study of online sport fandom practices are discussed at last.

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Plant growth can be limited by resource acquisition and defence against consumers, leading to contrasting trade-off possibilities. The competition-defence hypothesis posits a trade-off between competitive ability and defence against enemies (e.g. herbivores and pathogens). The growth-defence hypothesis suggests that strong competitors for nutrients are also defended against enemies, at a cost to growth rate. We tested these hypotheses using observations of 706 plant populations of over 500 species before and following identical fertilisation and fencing treatments at 39 grassland sites worldwide. Strong positive covariance in species responses to both treatments provided support for a growth-defence trade-off: populations that increased with the removal of nutrient limitation (poor competitors) also increased following removal of consumers. This result held globally across 4 years within plant life-history groups and within the majority of individual sites. Thus, a growth-defence trade-off appears to be the norm, and mechanisms maintaining grassland biodiversity may operate within this constraint.

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In this study, we describe a novel protein production platform that provides both activation and amplification of transgene expression in planta. The In Plant Activation (INPACT) system is based on the replication machinery of tobacco yellow dwarf mastrevirus (TYDV) and is essentially transient gene expression from a stably transformed plant, thus combining the advantages of both means of expression. The INPACT cassette is uniquely arranged such that the gene of interest is split and only reconstituted in the presence of the TYDV-encoded Rep/RepA proteins. Rep/RepA expression is placed under the control of the AlcA:AlcR gene switch, which is responsive to trace levels of ethanol. Transgenic tobacco (Nicotiana tabacum cv Samsun) plants containing an INPACT cassette encoding the b-glucuronidase (GUS) reporter had negligible background expression but accumulated very high GUS levels (up to 10% total soluble protein) throughout the plant, within 3 d of a 1% ethanol application. The GUS reporter was replaced with a gene encoding a lethal ribonuclease, barnase, demonstrating that the INPACT system provides exquisite control of transgene expression and can be adapted to potentially toxic or inhibitory compounds. The INPACT gene expression platform is scalable, not host-limited, and has been used to express both a therapeutic and an industrial protein.

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Alcohol restrictions have been implemented in many Indigenous communities internationally, with the aim to reduce alcohol-related harm. Whilst a range of reviews have evaluated such restrictions using different measures, drink driving has been described in several reviews as increasing. Presently, this remains anecdotal; with limited empirical evidence to corroborate these reports. In Australia, the Queensland government introduced alcohol management plans in remote Indigenous communities, during 2002-2003, with total alcohol prohibition commencing in 2008 in some communities. Given road crashes are one of the leading causes of injuries for Indigenous peoples, this study aims to identify if the restrictions have been successful in reducing drink driving or have increased such behaviour. We examine this by reviewing changes in conviction rates and in offender and offence characteristics following the 2008 restrictions. Using de-identified Queensland court drink driving conviction data (2006-2011), from four Indigenous communities, Robust Poisson regression models compared counts of drink driving convictions pre (2006-2008) versus post SRS (2009-2011). Changes in offender characteristics and conviction details (blood alcohol concentration (BAC) and sentencing severity), were examined using chi-squares. Results indicate a decline in convictions after the 2008 SRS in three communities. However, a significant increase in convictions was identified in one study community. Community-level disparity included significant decline in BAC in one community (Ï 2=5.58, p=0.02) compared with the three other communities that did not indicate change and a significant increase the number of women convicted in two communities (Ï 2=17.36, p<0.01; Ï 2=5.79, p=0.04). Alcohol restrictions may have important implications in road safety with these reductions in convictions and BAC in some communities. However, an increase in the number of women convicted and limited changes in BAC for other communities demonstrate the complex relationship between alcohol use, remoteness and driving. Greater focus on demand reduction strategies may be necessary to address alcohol misuse.

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Drink driving contributes towards high injury rates for Indigenous populations in Canada and Australia, particularly in more isolated regions. At present there is limited research on the cultural and psychosocial factors that underpin Indigenous peoplesâ drink driving. This study is part of a broader project aiming to inform a culturally sensitive program. Qualitative interviews with 29 convicted Indigenous drink drivers (aged 20-51 years) from a remote region of Queensland, Australia were used to explore their cognitions about, and underlying motivation for, drink driving as well as the factors that might facilitate or impede it. Although a number of themes were identified, this paper will focus on the first theme, respondentsâ self-perceived rationale for their behaviour. Two subthemes were identified: â˜being the heroâ referred to situations where respondents were motivated by a bravado mentality to drive after drinking despite having, on some occasions, the opportunity to avoid this (e.g. another person offering to drive); and â˜family obligationsâ which referred to situations where respondents described pressure from members of their extended families to drive after drinking. The underlying responsibility for transporting family members appeared to be difficult to avoid and related to cultural values. Findings indicate the social and individual characteristics for younger drink drivers are similar to mainstream populations. However, the reinforcers for Indigenous drink drivers may be different for this population, consistent with findings on other Indigenous populations outside Australia. Specific programs should contain a family-centred approach and explore the kinship value system to build strategies around these strong relationships.

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Structurally novel compounds able to block voltage-gated Ca2+ channels (VGCCs) are currently being sought for the development of new drugs directed at neurological disorders. Fluorescence techniques have recently been developed to facilitate the analysis of VGCC blockers in a multi-well format. By utilising the small cell lung carcinoma cell line, NCI-H146, we were able to detect changes in intracellular Ca2+ concentration ([Ca2+]i) using a fluorescence microplate reader. NCI-H146 cells have characteristics resembling those of neuronal cells and express multiple VGCC subtypes, including those of the L-, N- and P-type. We found that K+-depolarisation of fluo-3 loaded NCI-H146 cells causes a rapid and transient increase in fluorescence, which was readily detected in a 96-well plate. Extracts of Australian plants, including those used traditionally as headache or pain treatments, were tested in this study to identify those affecting Ca2+ influx following membrane depolarisation of NCI-H146 cells. We found that E. bignoniiflora, A. symphyocarpa and E. vespertilio caused dose-dependent inhibition of K+-depolarised Ca2+ influx, with IC50 values calculated to be 234, 548 and 209 μg/ml, respectively. This data suggests an effect of these extracts on the function of VGCCs in these cells. Furthermore, we found similar effects using a fluorescence laser imaging plate reader (FLIPR) that allows simultaneous measurement of real-time fluorescence in a multi-well plate. Our results indicate that the dichloromethane extract of E. bignoniiflora and the methanolic extract of E. vespertilio show considerable promise as antagonists of neuronal VGCCs. Further analysis is required to characterise the function of the bioactive constituents in these extracts and determine their selectivity on VGCC subtypes.

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A high performance liquid chromatographic method for the simultaneous determination of five organochlorine pesticides (aldrin, p,pâ-DDT, dieldrin, endrin, and heptachlor) was developed. The method was used to determine the levels of these pesticides in medicinal plant samples. Analysis was carried out using a Merck LiChrospher 100 RP C18 (5 μm) column with a gradient solvent system of acetonitrile-water and PDA UV detection (224 nm). Quantification was carried out by the external standard method. The limit of detection for the utilized method was below the local legal limits (ANZFA) for similar plant materials for all 5 pesticides excepting endrin. Medicinal plant extracts were further analyzed by conventional GC-ECD and GC-NPD means using SPE and GPC cleanup as required.

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This study investigates the role of development planning in empowering rural communities in Indonesiaâs decentralised era. Evidence is produced that the combination of procedural justice in planning development and social learning in its implementation can assist self-organisation and help empower local communities. Significant benefits are shown to result in: the acquisition and use of collective resources; the development of shared knowledge, skills, values and trust; community leadership; and the development of social networks. Two features of this empowerment model are community-based planning, utilising participatory rural appraisal at the level of the natural village, and the organisation of collective action. These are shown to be effective ways of incorporating procedural justice and social learning in self organisation and community empowerment.