993 resultados para Xanthophyll cycle Mehler-peroxidase reaction


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Commentators in the financial press claimed that the amendments to AASB 1010, Accounting for the Revaluation of Non-Current Assets, issued in September 1991, would have disastrous implications for the accounts of companies. This paper is concerned with whether the amendments did indeed affect asset write-down activities. An analysis of write-down practices of 75 Australian companies before and after the amendments were operative suggests that the commentators' judgment could have been hasty.

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Durland and McCurdy [Durland, J.M., McCurdy, T.H., 1994. Duration-dependent transitions in a Markov model of US GNP growth. Journal of Business and Economic Statistics 12, 279288] investigated the issue of duration dependence in US business cycle phases using a Markov regime-switching approach, introduced by Hamilton [Hamilton, J., 1989. A new approach to the analysis of time series and the business cycle. Econometrica 57, 357384] and extended to the case of variable transition parameters by Filardo [Filardo, A.J., 1994. Business cycle phases and their transitional dynamics. Journal of Business and Economic Statistics 12, 299308]. In Durland and McCurdys model duration alone was used as an explanatory variable of the transition probabilities. They found that recessions were duration dependent whilst expansions were not. In this paper, we explicitly incorporate the widely-accepted US business cycle phase change dates as determined by the NBER, and use a state-dependent multinomial Logit modelling framework. The model incorporates both duration and movements in two leading indexes one designed to have a short lead (SLI) and the other designed to have a longer lead (LLI) as potential explanatory variables. We find that doing so suggests that current duration is not only a significant determinant of transition out of recessions, but that there is some evidence that it is also weakly significant in the case of expansions. Furthermore, we find that SLI has more informational content for the termination of recessions whilst LLI does so for expansions.

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p53 is the central member of a critical tumor suppressor pathway in virtually all tumor types, where it is silenced mainly by missense mutations. In melanoma, p53 predominantly remains wild type, thus its role has been neglected. To study the effect of p53 on melanocyte function and melanomagenesis, we crossed the 'high-p53'Mdm4+/- mouse to the well-established TP-ras0/+ murine melanoma progression model. After treatment with the carcinogen dimethylbenzanthracene (DMBA), TP-ras0/+ mice on the Mdm4+/- background developed fewer tumors with a delay in the age of onset of melanomas compared to TP-ras0/+ mice. Furthermore, we observed a dramatic decrease in tumor growth, lack of metastasis with increased survival of TP-ras0/+: Mdm4+/- mice. Thus, p53 effectively prevented the conversion of small benign tumors to malignant and metastatic melanoma. p53 activation in cultured primary melanocyte and melanoma cell lines using Nutlin-3, a specific Mdm2 antagonist, supported these findings. Moreover, global gene expression and network analysis of Nutlin-3-treated primary human melanocytes indicated that cell cycle regulation through the p21WAF1/CIP1 signaling network may be the key anti-melanomagenic activity of p53.

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We consider time-space fractional reaction diffusion equations in two dimensions. This equation is obtained from the standard reaction diffusion equation by replacing the first order time derivative with the Caputo fractional derivative, and the second order space derivatives with the fractional Laplacian. Using the matrix transfer technique proposed by Ilic, Liu, Turner and Anh [Fract. Calc. Appl. Anal., 9:333--349, 2006] and the numerical solution strategy used by Yang, Turner, Liu, and Ilic [SIAM J. Scientific Computing, 33:1159--1180, 2011], the solution of the time-space fractional reaction diffusion equations in two dimensions can be written in terms of a matrix function vector product $f(A)b$ at each time step, where $A$ is an approximate matrix representation of the standard Laplacian. We use the finite volume method over unstructured triangular meshes to generate the matrix $A$, which is therefore non-symmetric. However, the standard Lanczos method for approximating $f(A)b$ requires that $A$ is symmetric. We propose a simple and novel transformation in which the standard Lanczos method is still applicable to find $f(A)b$, despite the loss of symmetry. Numerical results are presented to verify the accuracy and efficiency of our newly proposed numerical solution strategy.

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The global release of 250,000 US Embassy diplomatic cables to selected media sites worldwide through the WikiLeaks website, was arguably the major global media event of 2010. As well as the implications of the content of the cables for international politics and diplomacy, the actions of WikiLeaks and its controversial editor-in-chief, the Australian Julian Assange, bring together a range of arguments about how the media, news and journalism are being transformed in the 21st century. This paper will focus on the reactions of Australian online news media sites to the release of the diplomatic cables by WikiLeaks, including both the online sites of established news outlets such as The Australian, Sydney Morning Herald and The Age, the ABCs The Drum site, and online-only sites such as Crikey, New Matilda and On Line Opinion. The study focuses on opinion and commentary rather than straight news reportage, and analysis is framed around three issues: WikiLeaks and international diplomacy; implications of WikiLeaks for journalism; and WikiLeaks and democracy, including debates about the organisation and the ethics of its own practice. It also whether a WikiLeaks Effect has wider implications for how journalism is conducted in the future, particularly the method of redaction of large amounts of computational data.

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This study of photocatalytic oxidation of phenol over titanium dioxide films presents a method for the evaluation of true reaction kinetics. A flat plate reactor was designed for the specific purpose of investigating the influence of various reaction parameters, specifically photocatalytic film thickness, solution flow rate (18 l min1), phenol concentration (20, 40 and 80 ppm), and irradiation intensity (70.6, 57.9, 37.1and 20.4 W m2), in order to further understand their impact on the reaction kinetics. Special attention was given to the mass transfer phenomena and the influence of film thickness. The kinetics of phenol degradation were investigated with different irradiation levels and initial pollutant concentration. Photocatalytic degradation experiments were performed to evaluate the influence of mass transfer on the reaction and, in addition, the benzoic acid method was applied for the evaluation of mass transfer coefficient. For this study the reactor was modelled as a batch-recycle reactor. A system of equations that accounts for irradiation, mass transfer and reaction rate was developed to describe the photocatalytic process, to fit the experimental data and to obtain kinetic parameters. The rate of phenol photocatalytic oxidation was described by a LangmuirHinshelwood type law that included competitive adsorption and degradation of phenol and its by-products. The by-products were modelled through their additive effect on the solution total organic carbon.

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This paper uses the lens of life-cycle thinking to discuss recent developments in the Australian mass market fashion industry, and to explore the opportunities and barriers to implementing lifecycle thinking within mass market design processes. Life-cycle analysis is a quantitative tool used to assess the environmental impact of a material or product. However the underlying thinking of life-cycle analysis can also be employed more generally, enabling a designer to assess their processes and design decisions for sustainability. A fashion designer employing life cycle thinking would consider every stage in the life of a garment from fibre and textiles through to consumer use, to eventual disposal and beyond disposal to reuse and later disassembly for fibre recycling. Although life-cycle thinking is rarely considered in the design processes of the fast-paced, price-driven mass market, this paper explores its potential and suggests ways in which it could be implemented.