Nano structures through self-assembly of protected hydrophobic amino acids: encapsulation of rhodamine B dye by proline-based nanovesicles

The development of novel molecules for the creation of nanometer structures with specific properties has been the current interest of this research. We have developed a set of molecules from hydrophobic omega- and alpha-amino acids by protecting the -NH(2) with Boc (t-butyloxycarbonyl) group and -CO(2)H with para-nitroanilide such as BocHN-Xx-CONH-(p-NO(2))center dot C(6)H(4), where Xx is gamma-aminobutyric acid (gamma-Abu), (L)-isoleucine, alpha-aminoisobutyric acid, proline, etc. These molecules generate various nanometer structures, such as nanofibrils, nanotubes and nanovesicles, in methanol/water through the self-assembly of bilayers in which the nitro benzene moieties are stacked in the middle and the Boc-protected amino acids parts are packed in the outer surface. The bilayers can be further stacked one over the other through hydrophobic interactions to form multilayer structure, which helps to generate different kinds of nanoscopic structures. The formation of the nanostructures has been facilitated through the participation of various noncovalent interactions, such as hydrophobic interactions, hydrogen bonding and aromatic p-stacking interactions. Fluorescence microscopy and UV studies reveal that the nanovesicles generated from pro-based molecule can encapsulate dye molecules which can be released by addition of acid (at pH 2). These single amino acid based molecules are both easy to synthesize and cost-effective and therefore offer novel scaffolds for the future design of nanoscale structures.

The benefits of a compute cluster approach to high spatial resolution biodiversity richness modelling: projecting the impact of climate change on Mediterranean flora

High spatial resolution environmental data gives us a better understanding of the environmental factors affecting plant distributions at fine spatial scales. However, large environmental datasets dramatically increase compute times and output species model size stimulating the need for an alternative computing solution. Cluster computing offers such a solution, by allowing both multiple plant species Environmental Niche Models (ENMs) and individual tiles of high spatial resolution models to be computed concurrently on the same compute cluster. We apply our methodology to a case study of 4,209 species of Mediterranean flora (around 17% of species believed present in the biome). We demonstrate a 16 times speed-up of ENM computation time when 16 CPUs were used on the compute cluster. Our custom Java ‘Merge’ and ‘Downsize’ programs reduce ENM output files sizes by 94%. The median 0.98 test AUC score of species ENMs is aided by various species occurrence data filtering techniques. Finally, by calculating the percentage change of individual grid cell values, we map the projected percentages of plant species vulnerable to climate change in the Mediterranean region between 1950–2000 and 2020.

Reconstruction of geomagnetic activity and near-Earth interplanetary conditions over the past 167 yr – Part 2: A new reconstruction of the interplanetary magnetic field

We present a new reconstruction of the interplanetary magnetic field (IMF, B) for 1846–2012 with a full analysis of errors, based on the homogeneously constructed IDV(1d)composite of geomagnetic activity presented in Part 1 (Lockwood et al., 2013a). Analysis of the dependence of the commonly used geomagnetic indices on solar wind parameters is presented which helps explain why annual means of interdiurnal range data, such as the new composite, depend only on the IMF with only a very weak influence of the solar wind flow speed. The best results are obtained using a polynomial (rather than a linear) fit of the form B = χ · (IDV(1d) − β)α with best-fit coefficients χ = 3.469, β = 1.393 nT, and α = 0.420. The results are contrasted with the reconstruction of the IMF since 1835 by Svalgaard and Cliver (2010).

Avoiding the dark side of positive online consumer reviews: enhancing reviews' usefulness for high risk-averse travelers

The influence of positive online consumer reviews on a traveler's decision making remains unclear. To better understand the perceived usefulness of online reviews, this study conducts two experiments using positive and negative online consumer reviews. Study results suggest that high risk-averse travelers find negative online reviews more useful than positive reviews. For positive online reviews, high-risk averse travelers feel expert reviewers' postings, travel product pictures, and well-known brand names enhance usefulness of the positive online reviews. These findings offer interesting implications for both marketing theory and practice.

IFRS for SMEs: the IASB’S due process

This study explores the role of the International Accounting Standards Board’s (IASB) due process in developing its International Financial Reporting Standards for Small and Medium-sized Entities (IFRS or SMEs)standard. There were tensions between the IASB’s desire to minimise divergence from full IFRS and preserve recognition and measurement principles, and the primary reasons for undertaking the project – to meet the needs of users of financial statements of SMEs and to reduce the financial reporting burden on SMEs. Examination of events during the development of the project reveals much that was not apparent from material in the public domain. Most significantly, the IASB recognised that the final title of the standard, IFRS for SMEs, does not necessarily describe the scope of the standard. This paper also shows that the due process followed in the case of the IFRS for SMEs project barely reflected the ‘will of people’ but was more inclined towards acting as a communicative function for the IASB without any commitment to change its stance on the SME standard.

Lithothamnion superpositum (Corallinales; Rhodophyta): First description for the Western Atlantic or rediscovery of a species?

P>Nongeniculate Corallinaceae are poorly known in Brazil. In our endeavor to identify this group of seaweeds along the Brazilian coast we came across some specimens that fit well into the accepted circumscription of Litothamnion Heydrich. Within this genus they could be identified to what has been called L. superpositum Foslie. The specimens were represented by nongeniculate, free living specimens (rhodoliths); lumpy to fruticose growth-form, presenting flared epithallial cells in transversal section; multiporate tetrasporangial conceptacles, with roof protruding above or flush with the surrounding thallus surface; chambers 250-525 mu m in diameter and 150-230 mu m high, roof structured by filaments with 3-5 cells long; and pores in depression. Among the species described from the Brazilian coast, L. heteromorphum (Foslie) Foslie presented anatomical and reproductive characteristics similar to the referred species described from southern Africa and Australia. Therefore, we propose to consider L. heteromorphum as a heterotypic synonym of L. superpositum and extending its distribution to the Western Atlantic.

Germination and survival of tetraspores of Kappaphycus alvarezii var. alvarezii (Solieriaceae, Rhodophyta) introduced in subtropical waters of Brazil

The carrageenophyte Kappaphycus alvarezii was introduced in 1995 and vegetatively propagated in Ubatuba, Sao Paulo State, Brazil, for the purpose of commercial cultivation. This species produces tetraspores mainly in the austral summer and fall. Tetraspore germination and survival were studied under different conditions of temperature, photon flux density, and photoperiod in the laboratory. Field experiments were also carried out. Although tetraspores of K. alvarezii germinated, they had low survival rates, most dying after 20 days. Recruitment of K. alvarezii tetraspores did not occur in experiments conducted in the field. The results indicated that the establishment of K. alvarezii via spore production in the natural environment of the south-east coast of Brazil is rather remote.

Synthesis optimization, structural evolution and optical properties of Y(0.9)Er(0.1)Al(3)(BO(3))(4) nanopowders obtained by soft chemistry methods

This paper describes the structural evolution of Y(0.9)Er(0.1)Al(3)(BO(3))(4) nanopowders using two soft chemistry routes, the sol-gel and the polymeric precursor methods. Differential scanning calorimetry, differential thermal analyses, thermogravimetric analyses, X-ray diffraction, Fourier-transform infrared, and Raman spectroscopy techniques have been used to study the chemical reactions between 700 and 1200 degrees C temperature range. From both methods the Y(0.9)Er(0.1)Al(3)(BO(3))(4) (Er:YAB) solid solution was obtained almost pure when the powdered samples were heat treated at 1150 degrees C. Based on the results, a schematic phase formation diagram of Er:YAB crystalline solid solution was proposed for powders from each method. The Er:YAB solid solution could be optimized by adding a small amount of boron oxide in excess to the Er:YAB nominal composition. The nanoparticles are obtained around 210 nm. Photoluminescence emission spectrum of the Er:YAB nanocrystalline powders was measured on the infrared region and the Stark components of the (4)I(13/2) and (4)I(15/2) levels were determined. Finally, for the first time the Raman spectrum of Y(0.9)Er(0.1)Al(3)(BO(3))(4) crystalline phase is also presented. (C) 2008 Elsevier Masson SAS. All rights reserved.

Gathering for God : George Brown in Oceania

Combining 'the gathering of artefacts with the gathering of souls', George Brown was a key figure in the Christian, and especially the Wesleyan Methodist, history of nineteenth-century Oceania. Using his life as a case study, Helen Bethea Gardner examines the role of Christian missionaries in the Pacific Islands. Brown's career (1860-1908) spanned one of the most tumultuous political periods in the South Pacific, as one by one islands were colonised by imperial nations. He was one of the most politically engaged of all missionaries, encouraging colonial rule in the Pacific by America, Britain, Germany and, eventually, Australia and New Zealand. Originally from the north of England, he worked as a missionary in Samoa from 1860, moving to the Bismarck Archipelago (now Papua New Guinea) in 1875. From the 1880s until his retirement in 1907, he worked in Sydney as the general secretary of the Australasian Methodist Overseas Mission. Gathering for God examines Brown's missionary letters, journals and journalism, exploring how he attracted Pacific Islanders to Christian teachings, analysing his leadership during an armed attack on New Britain villages accused of cannibalism, and looking at his work in the new discipline of anthropology. He was a major collector of artefacts (his collection is now in the Osaka Museum) and photographer of Pacific peoples (his collection is in the Australian Museum).

Application of the fair-value concept : evidence from Australian legal decisions

The concept of "fair value" is increasingly being incorporated into Australian and international accounting standards and pronouncements. The fair-value concept has also been established and developed in Australian legal cases, and an examination of pertinent court decisions is of interest to accountants. By examining and analysing relevant cases, the paper highlights some of the principles and difficulties involved in operationalising the fair-value concept for accounting and legal purposes, particularly in situations where the asset being valued is subject to imperfect or incomplete markets.

Corporate social responsibility: why business should act responsibly and be accountable

This paper identifies drivers which are pressurising organisations to adopt corporate social responsibility and produce corporate social reports. The authors discuss what constitutes a good report, some of the problems with current reporting practices, benefits to organisations which produce corporate social reports and the costs to those which do not.

Accountants, ethical issues and the corporate governance context

A major survey of members of CPA Australia on the issue of ethics was recently conducted. A questionnaire was sent to 7,000 members at random, with those surveyed being asked whether they had come across any one of 14 ethical issues in the previous year. They were also asked to list the issues in order of importance as regards maintaining ethical standards, even if they had not been confronted by them.

Public interest, ethics, and the balanced scorecard: implications for the accounting profession

The accounting profession bos been grappling with the issue of public interest responsibility for a number of years. The aim of this paper is to examine how a balanced scorecard (BSC) model can be used by the accounting profession to more effectively incorporate a public interest responsibility in its strategic framework. By using a BSC model, the paper provides an integrated framework for translating strategic values into a comprehensive set of objectives, performance measures and improvement actions.