993 resultados para 7139-204


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Recently, second-generation (non-vegetable oil) feedstocks for biodiesel production are receiving significant attention due to the cost and social effects connected with utilising food products for the production of energy products. The Beauty leaf tree (Calophyllum inophyllum) is a potential source of non-edible oil for producing second-generation biodiesel because of its suitability for production in an extensive variety of atmospheric condition, easy cultivation, high fruit production rate, and the high oil content in the seed. In this study, oil was extracted from Beauty leaf tree seeds through three different oil extraction methods. The important physical and chemical properties of these extracted Beauty leaf oils were experimentally analysed and compared with other commercially available vegetable oils. Biodiesel was produced using a two-stage esterification process combining of an acid catalysed pre-esterification process and an alkali catalysed transesterification process. Fatty acid methyl ester (FAME) profiles and important physicochemical properties were experimentally measured and estimated using equations based on the FAME analysis. The quality of Beauty leaf biodiesels was assessed and compared with commercially available biodiesels through multivariate data analysis using PROMETHEE-GAIA software. The results show that mechanical extraction using a screw press produces oil at a low cost, however, results in low oil yields compared with chemical oil extraction. High pressure and temperature in the extraction process increase oil extraction performance. On the contrary, this process increases the free fatty acid content in the oil. A clear difference was found in the physical properties of Beauty leaf oils, which eventually affected the oil to biodiesel conversion process. However, Beauty leaf oils methyl esters (biodiesel) were very consistent physicochemical properties and able to meet almost all indicators of biodiesel standards. Overall this study found that Beauty leaf is a suitable feedstock for producing second-generation biodiesel in commercial scale. Therefore, the findings of this study are expected to serve as the basis for further development of Beauty leaf as a feedstock for industrial scale second-generation biodiesel production.

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Endometriosis is a complex disease that affects 6-10% of women in their reproductive years and 20-50% of women with infertility. Genome-wide and candidate-gene association studies for endometriosis have identified 10 independent risk loci, and of these, nine (rs7521902, rs13394619, rs4141819, rs6542095, rs1519761, rs7739264, rs12700667, rs1537377, and rs10859871) are polymorphic in European populations. Here we investigate the replication of nine SNP loci in 998 laparoscopically and histologically confirmed endometriosis cases and 783 disease-free controls from Belgium. SNPs rs7521902, rs13394619, and rs6542095 show nominally significant (p <.05) associations with endometriosis, while the directions of effect for seven SNPs are consistent with the original reports. Association of rs6542095 at the IL1A locus with 'All' (p =.066) and 'Grade-B' (p =.01) endometriosis is noteworthy because this is the first successful replication in an independent population. Meta-analysis with the published results yields genome-wide significant evidence for rs7521902, rs13394619, rs6542095, rs12700667, rs7739264, and rs1537377. Notably, three coding variants in GREB1 (near rs13394619) and CDKN2B-AS1 (near rs1537377) also showed nominally significant associations with endometriosis. Overall, this study provides important replication in a uniquely characterized independent population, and indicates that the majority of the original genome-wide association findings are not due to chance alone. © The Author(s) 2015.

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This analysis of all carapace length measurements collected between 1989 and 2009, during scientific surveys, describes the variation of tropical rock lobster, Panulirus ornatus, somatic growth in Torres Strait. Multiple models of carapace length frequency distributions were compared by maximum likelihood to determine which hypotheses were most supported by the data. The best model assumed sex and cohort-specific Von Bertalanffy's parameters. These estimates are consistent with results derived from tagging data collected in the 1980s and provide new information on parameters' uncertainty. In the past two decades, growth rates have fluctuated inter-annually without displaying any distinctive trend. Associated uncertainties are large, suggesting that sampling will need to be intensified in order to detect an effect of climate change.

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In boreal forests, microorganisms have a pivotal role in nutrient and water supply of trees as well as in litter decomposition and nutrient cycling. This reinforces the link between above-ground and below-ground communities in the context of sustainable productivity of forest ecosystems. In northern boreal forests, the diversity of microbes associated with the trees is high compared to the number of distinct tree species. In this thesis, the aim was to study whether conspecific tree individuals harbour different soil microbes and whether the growth of the trees and the community structure of the associated microbes are connected. The study was performed in a clonal field trial of Norway spruce, which was established in a randomized block design in a clear-cut area. Since out-planting in 1994, the spruce clones showed two-fold growth differences. The fast-growing spruce clones were associated with a more diverse community of ectomycorrhizal fungi than the slow-growing spruce clones. These growth performance groups also differed with respect to other aspects of the associated soil microorganisms: the species composition of ectomycorrhizal fungi, in the amount of extraradical fungal mycelium, in the structure of bacterial community associated with the mycelium, and in the structure of microbial community in the organic layer. The communities of fungi colonizing needle litter of the spruce clones in the field did not differ and the loss of litter mass after two-years decomposition was equal. In vitro, needles of the slow-growing spruce clones were colonized by a more diverse community of endophytic fungi that were shown to be significant needle decomposers. This study showed a relationship between the growth of Norway spruce clones and the community structure of the associated soil microbes. Spatial heterogeneity in soil microbial community was connected with intraspecific variation of trees. The latter may therefore influence soil biodiversity in monospecific forests.

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This study aims to explore the use of Twitter for professional purposes. The researcher discovered that Twitter is widely perceived as an information ground in online spaces. Information grounds are social settings where information, people, and places come together to create an information flow within a physical environment. Twitter provides a sense of place as well as a sense of belonging that enables IT professionals to use Twitter for professional development. The data for this study were collected using online observations and interviews. The online observations helped the researcher to distinguish the ‘information behaviours’ (the objective and observable actions) of the participants. The interviews were used to understand the way IT professionals use Twitter for professional purposes through their own individual perspectives. The data were analysed using a constructive grounded theory. The findings show that building professional networking is extremely important to IT professionals; rather than the information-seeking and information-sharing aspects of Twitter. Building professional networking in microblogging has a significant influence on an individual’s professional development. The results also demonstrate that IT professionals are more likely to exploit their weak-ties rather than their strong-ties on Twitter. In short, these users experience Twitter as a real place or ‘information grounds’ where they meet and socialise with experts.

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Infrared spectra of oxazolidine-2-one (Oxo), -2-thione (Oxt) and their N-deuteriated derivatives have been measured over the range 4000-20 cm−1. The fundamental frequencies of these molecules have been assigned on the basis of normal coordinate calculations carried out using a Urey-Bradley potential function supplemented with valence type constants for the out-of-plane modes of the planar skeleton. The results of the vibrational analyses are discussed and correlated with the assignments available for the other related five membered heterocyclic molecules.

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A method has been presented for constructing non-separable solutions of homogeneous linear partial differential equations of the type F(D, D′)W = 0, where D = ∂/∂x, D′ = ∂/∂y, Image where crs are constants and n stands for the order of the equation. The method has also been extended for equations of the form Φ(D, D′, D″)W = 0, where D = ∂/∂x, D′ = ∂/∂y, D″ = ∂/∂z and Image As illustration, the method has been applied to obtain nonseparable solutions of the two and three dimensional Helmholtz equations.

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Many Australian courts now prefer pre-hearing meetings of experts (conclaves) being convened to prepare joint reports to identify areas of agreement and disagreement, followed by concurrent expert evidence at trial. This contrasts to the traditional approach where experts did not meet before trial and did not give evidence together. Most judges, lawyers and expert witnesses favour this as a positive development in Australian legal practice, at least for civil disputes. This new approach impacts medical practitioners who are called upon to give expert evidence, or who are parties to disputes before the courts. Arguably, it is too soon to tell whether the relative lack of transparency at the conclave stage will give rise to difficulties in the coronial, disciplinary and criminal arenas.

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Alternative sources of N are required to bolster subtropical cereal production without increasing N2O emissions from these agro-ecosystems. The reintroduction of legumes in cereal cropping systems is a possible strategy to reduce synthetic N inputs but elevated N2O losses have sometimes been observed after the incorporation of legume residues. However, the magnitude of these losses is highly dependent on local conditions and very little data are available for subtropical regions. The aim of this study was to assess whether, under subtropical conditions, the N mineralised from legume residues can substantially decrease the synthetic N input required by the subsequent cereal crop and reduce overall N2O emissions during the cereal cropping phase. Using a fully automated measuring system, N2O emissions were monitored in a cereal crop (sorghum) following a legume pasture and compared to the same crop in rotation with a grass pasture. Each crop rotation included a nil and a fertilised treatment to assess the N availability of the residues. The incorporation of legumes provided enough readily available N to effectively support crop development but the low labile C left by these residues is likely to have limited denitrification and therefore N2O emissions. As a result, N2O emissions intensities (kgN2O-N yield-1ha-1) were considerably lower in the legume histories than in the grass. Overall, these findings indicate that the C supplied by the crop residue can be more important than the soil NO3 - content in stimulating denitrification and that introducing a legume pasture in a subtropical cereal cropping system is a sustainable practice from both environmental and agronomic perspectives.

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This study examined the psychometric properties of a Persian translation of the Career Adapt-Abilities Scale (CAAS—Iran Form) and its relationships with career satisfaction, business opportunity identification, and entrepreneurial intentions. It was hypothesized that career adaptability relates positively to these three outcomes, even when controlling for demographic and employment characteristics. Data were provided by 204 workers from Iran. Results showed that the overall CAAS score and sub-dimension scores (concern, control, curiosity, and confidence) were highly reliable. Moreover, confirmatory factor analyses indicated that the CAAS—Iran Form measures four distinct dimensions that can be combined into a higher-order career adaptability factor. Findings also demonstrated criterion-related validity of the scale with regard to career satisfaction and entrepreneurial intentions. In contrast, overall career adaptability was not significantly related to opportunity identification, while concern related positively, and control related negatively to opportunity identification. Overall, the CAAS—Iran Form has very good psychometric properties and predicts important career outcomes, suggesting that it can be used for career counseling and future research with Persian-speaking workers.

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MANY cyclic peptides have interesting biological functions and the details of their molecular structure and conformation have been the subject of extensive investigations. Cyclic dipeptides such as diketopiperazine have been synthesised and shown to occur with the peptide units in the cis configuration1,2. In the case of a tripeptide, cyclisation can take place only if all three units are in the cis configuration3. In cyclic peptides with four units also, cis peptides are found4,5. As the number of the peptide units increases, the more stable trans configuration is generally more common6,7. We report here the main results of our X-ray crystallographic investigations of the cyclic tripeptides L-Pro-L-Pro-L-Pro and L-Pro-L-Pro-L-Hyp (hereafter called CTP 1 and CTP 2, respectively). CTP 1 was synthesised by Rothe et al. 8 and its derivatives have been prepared by Blout and his collaborators9.

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The production of sustainable housing requires the cooperation of a variety of participants with different goals, needs, levels of commitment and cultures. To achieve mainstream net zero energy housing objectives, there is arguably a need for a non-linear network of collaboration between all the stakeholders. In order to create and improve such collaborative networks between stakeholders, we first need to map stakeholders’ relationships, processes, and practices. This paper discusses compares and contrasts maps of the sustainable housing production life-cycle in Australia, developed from different perspectives. The paper highlights the strengths and weaknesses of each visualization, clarifying where gaps in connectivity exist within existing industry networks. Understanding these gaps will help researchers and practitioners identify how to improve the collaboration between participants in the housing industry. This in turn may improve decision making across all stakeholder groups, leading to mainstream implementation of sustainability into the housing industry.

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This special edition of the International Journal of Critical Indigenous Studies focuses upon the work scholars within the growing discipline of Aboriginal and Torres Strait Islander health studies. The lamentable state of Indigenous health in Australia is reflected in Indigenous populations elsewhere, especially where settler colonialism has left an indelible mark. This special edition therefore speaks to where Indigenous health outcomes and the efficacy of remedies are causing concern. Common to all is the demand that Indigenous people are placed front and centre of all attempts to improve health outcomes and that improvements are sought in culturally sensitive ways. Terry Dunbar presents findings from a research study that set out to investigate the Indigenous experiences of health and family services in the Northern Territory, Australia. The study asserts that cultural security is an integral and vital element of any policy that will impact upon Indigenous peoples. Dunbar concludes by arguing that in seeking positive change with regard to cultural security or otherwise, the most vociferous champions of that change are likely to be the Aboriginal communities affected. The article by Bronwyn Fredericks, Karen Adams, Sandra Angus and Melissa Walker also highlights the need to involve Aboriginal and Torres Strait Islander people, in this case women, in the design and development of strategies affecting their lives. Utilising routine communication methods such the ‘talking circle’ and the process referred to as ‘talkin’ up’, where women ‘talk back’ to one another about issues of personal importance, the article argues that the health strategy which emerged through these consultation approaches was more accurately informed by and responsive to women’s health need. Indeed, the resulting strategy reflected the women’s sense of themselves and the clear direction they felt their health services and polices should take.

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The binding of chromomycin A3, an antitumour antibiotic, to various DNA and chromatin isolated from mouse and rat liver, mouse fibrosarcoma and Yoshida ascites sarcoma cells was studied spectrophotometrically at 29°C in 10−2 M Tris-HCl buffer, pH 8.0, containing small amounts of MgCl2 (4.5 · 10−5−25 · 10−5 M). An isobestic point at 415 nm was observed when chromomycin A3 was gradually titrated with Image and its spectrum shifted towards higher wavelength. The rates and extent of these spectral changes were found to be dependent on the concentration of Mg2+. The change in absorbance at 440 nm was used to calculate apparent binding constant (Ka p M−1) and sites per nucleotide (n) from Scatchard plots for various DNA and chromatins. As expected, values of n for chromatin (0.06–0.10) were found to be lower than that found for corresponding DNA (0.10–0.15). Apparently no such correlation exists between binding constants (Ka p M−1 · 10−4) of DNA (6.4–11.2) and of chromatin (3.1–8.3), but Ka p M−1 of chromatin isolated from mouse fibrosarcoma and Yoshida ascites sarcoma are 1.5–3 times higher than that found for mouse and rat liver chromatin. These differences may be taken to indicate structural difference in nucleoprotein complexes caused by neoplasia. The relevance of this finding to tumour suppressive action of chromomycin A3 is discussed.

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The theoretical analysis, based on the perturbation technique, of ion-acoustic waves in the vicinity of a Korteweg-de Vries (K-dV) equation derived in a plasma with some negative ions has been made. The investigation shows that the negative ions in plasma with isothermal electrons introduced a critical concentration at which the ion-acoustic wave plays an important role of wave-breaking and forming a precursor while the plasma with non-isothermal electrons has no such singular behaviour of the wave. These two distinct features of ion waves lead to an overall different approach of present study of ion-waves. A distinct feature of non-uniform transition from the nonisothermal case to isothermal case has been shown. Few particular plasma models have been chosen to show the characteristics behaviour of the ion-waves existing in different cases