Structure and mechanical properties of asymmetrically rolled IF steel sheet

As-received hot-rolled 5.6 mm thick IF steel sheet was symmetrically/ asymmetrically cold rolled at room temperature down to 1.9 mm. The asymmetric rolling was carried out in monotonic (an idle roll is always on the same side of the sheet) and reversal (the sheet was turned 180° around the rolling direction between passes) modes. Microstructure, texture and mechanical properties were analysed. The observed differences in structure and mechanical properties were modest, and therefore further investigation of the effects of other kinds of asymmetry is suggested.

Compensatory growth in an aquatic plant mediates exploitative competition between seasonally tied herbivores

The degree to which vertebrate herbivores exploitatively compete for the same food plant may depend on the level of compensatory plant growth. Such compensation is higher when there is reduced density-dependent competition in plants after herbivore damage. Whether there is relief from competition may largely be determined by the life-history stage of plants under herbivory. Such stage-specific compensation may apply to seasonal herbivory on the clonal aquatic plant sago pondweed (Potamogeton pectinatus L.). It winters in sediments of shallow lakes as tubers that are foraged upon by Bewick's Swans (Cygnus columbianus bewickii Yarrell), whereas aboveground biomass in summer is mostly consumed by ducks, coots, and Mute Swans. Here, tuber predation may be compensated due to diminished negative density dependence in the next growth season. However, we expected lower compensation to summer herbivory by waterfowl and fish as density of aboveground biomass in summer is closely related to photosynthetic carbon fixation. In a factorial exclosure study we simultaneously investigated (1) the effect of summer herbivory on aboveground biomass and autumn tuber biomass and (2) the effect of tuber predation in autumn on aboveground biomass and tuber biomass a year later. Summer herbivory strongly influenced belowground tuber biomass in autumn, limiting food availability to Bewick's Swans. In contrast, tuber predation in autumn by Bewick's Swans had a limited and variable effect on P. pectinatus biomass in the following growth season. Whereas relief from negative density dependence largely eliminates effects of belowground herbivory by swans, aboveground herbivory in summer limits both above- and belowground plant biomass. Hence, there was an asymmetry in exploitative competition, with herbivores in summer reducing food availability for belowground herbivores in autumn, but not the other way around.

What drives stock markets over short horizons? Evidence from emerging markets

The goal of this paper is to examine the importance of permanent and transitory shocks in explaining variations in stock prices for Singapore, Taiwan, and South Korea using a trend-cycle decomposition technique. This study is novel in that in measuring the impact of shocks we not only impose common trend restrictions but also common cycle restrictions. We later undertake a post-sample forecasting exercise to confirm the efficiency gains from imposing common cycle restrictions. We find that over short horizons, transitory shocks are the dominant source of variations in stock prices for South Korea, while permanent shocks explain the bulk of the variations in stock price of Singapore and Taiwan.

An in situ method for the study of strain broadening using synchrotron X-ray diffraction

A tensonometer for stretching metal foils has been constructed for the study of strain broadening in X-ray diffraction line profiles. This device, which is designed for use on powder diffractometers and was tested on Station 2.3 at Daresbury Laboratory, allows in situ measurements to be performed on samples under stress. It can be used for data collection in either transmission or reflection modes using either symmetric or asymmetric diffraction geometries. As a test case, measurements were carried out on an 18 µm-thick copper foil experiencing strain levels of up to 5% using both symmetric reflection and symmetric transmission diffraction. All the diffraction profiles displayed peak broadening and asymmetry which increased with strain. The measured profiles were analysed by the fundamental-parameters approach using the TOPAS peak-fitting software. All the observed broadened profiles were modelled by convoluting a refineable diffraction profile, representing the dislocation and crystallite size broadening, with a fixed instrumental profile predetermined using high-quality LaB6 reference powder. The deconvolution process yielded `pure' sample integral breadths and asymmetry results which displayed a strong dependence on applied strain and increased almost linearly with applied strain. Assuming crystallite size broadening in combination with dislocation broadening arising from f.c.c. a/2〈110〉{111} dislocations, the variation of mechanical property with strain has been extracted. The observation of both peak asymmetry and broadening has been interpreted as a manifestation of a cellular structure with cell walls and cell interiors possessing high and low dislocation densities.

In-situ studies of X-ray diffraction line profiles from strained copper foils

The development of an in-situ tensometer is described along with preliminary results of x-ray line profiles from copper foils under tensile stress. The tensometer was designed and constructed on the high resolution diffraction instrument, Station 2.3 at the synchrotron radiation source (SRS) Daresbury Laboratory, and is capable of collecting data in either symmetric or asymmetric geometry including transmission and reflection modes. Experiments were carried out using 18 J..Lm thick copper foil up to strain levels of 5 % using both symmetric reflection and symmetric transmission diffraction. All profiles displayed diffraction broadening and asymmetry which increased with strain. In addition, the asymmetry observed in symmetric transmission was associated with extended tails on the low angle side of the profiles, but in symmetric reflection data the opposite asymmetry was observed. In the analysis, the measured profiles were fitted using the software TOPAS, a fundamental parameters approach to profile fitting. The instrumental profile function was characterised and modelled using annealed LaB6 powder. The diffraction broadening was then determined by refining the convolution of a Voigt function, an asymmetric exponential function and a fixed instrument function to reproduce the observed broadened profiles. The integral breadth and asymmetry results display a strong order dependence and increase almost linearly with strain. The results were interpreted by assuming crystallite size broadening in combination with dislocation broadening arising from fcc a/2( 110) {Ill } dislocations.

Exploring the moderating role of growth options on the relation between board characteristics and management earnings forecasts

Manuscript Type
Empirical
Research Question/Issue
This study examines whether director independence, reputation, and financial expertise are related to management earnings forecast (MEF) activity. In particular, we examine whether such a relationship is moderated by firms’ growth options.
Research Findings/Insights
Using Australian archival data for 1,928 firm-years between 1999 and 2006, we find several board characteristics have a significant positive relationship with: (1) the likelihood of firms issuing MEFs; (2) their specificity; (3) their accuracy; and (4) a negative relationship with their bias. For (1), (2), and (3) we show that these relationships are accentuated for firms with high growth options.
Theoretical/Academic Implications
While the theory of voluntary disclosure suggests firms will disclose information that is favorable to them or their managers, well-governed firms issue informative MEFs that potentially reduce information asymmetries in capital markets. We extend the prior literature by showing that such a relation is enhanced in the presence of information asymmetry and moral hazard associated with growth options.
Practitioner/Policy Implications
Our results have strategic implications for nomination committees by showing that independent directors and those with strong reputations and financial expertise enhance the governance of high growth firms. We also inform the regulatory debate by showing that good corporate governance enhancing disclosure quality is context-specific – it is not a case of “one size fits all”.

Market failure, policy failure and other distortions in chronic disease markets

Background: The increasing prevalence of chronic disease represents a significant burden on most health systems. This paper explores the market failures and policy failures that exist in the management of chronic diseases.
Discussion: There are many sources of market failure in health care that undermine the efficiency of chronic disease management. These include incomplete information as well as information asymmetry between providers and consumers, the effect of externalities on consumer behaviour, and the divergence between social and private time preference rates. This has seen government and policy interventions to address both market failures and distributional issues resulting from the inability of private markets to reach an efficient and equitable distribution of resources. However, these have introduced a series of policy failures such as distorted re-imbursement arrangements across modalities and delivery settings.
Summary: The paper concludes that market failure resulting from a preference of individuals for 'immediate gratification' in the form of health care and disease management, rather than preventative services, where the benefits are delayed, has a major impact on achieving an efficient allocation of resources in markets for the management of chronic diseases. This distortion is compounded by government health policy that tends to favour medical and pharmaceutical interventions further contributing to distortions in the allocation of resources and inefficiencies in the management of chronic disease.

Asymmetric rolling of interstitial-free steel using differential roll diameters. Part I : mechanical properties and deformation textures

IF steel sheets were processed by conventional symmetric and asymmetric rolling (ASR) at ambient temperature. The asymmetry was introduced in a geometric way using differential roll diameters with a number of different ratios. The material strength was measured by tensile testing and the microstructure was analyzed by optical and transmission electron microscopy as well as electron backscatter diffraction (EBSD) analysis. Texture was also successfully measured by EBSD using large surface areas. Finite element (FE) simulations were carried out for multiple passes to obtain the strain distribution after rolling. From the FE results, the velocity gradient along selected flow lines was extracted and the evolution of the texture was simulated using polycrystal plasticity modeling. The best mechanical properties were obtained after ASR using a roll diameter ratio of 2. The textures appeared to be tilted up to 12 deg around the transverse direction, which were simulated with the FE-combined polycrystal plasticity modeling in good agreement with measurements. The simulation work revealed that the shear component introduced by ASR was about the same magnitude as the normal component of the rolling strain tensor.

Technology transfer, quality standards, and North–South trade

This paper examines the economic consequences of technology transfer through licensing in a North–South model of vertical product differentiation, based on a product-line pricing framework. With its limited technological expertise, the southern firm cannot export to the northern market without purchasing the northern firm's “clean” and low-cost technology. With North–South cost-asymmetry, we conclude that the transfer of technology through licensing promotes trade, product variety and improves global welfare. However, without government intervention, the private levels of product quality chosen by firms tend to be lower than the socially optimal levels. This finding helps to explain why developed countries often set quality standards for imported foreign products.

Na partitioning during thermomechanical processing of an Mg-Sn-Zn-Na alloy

Microstructural characterization was used to examine the changes that occur in an Mg-6Sn-5Zn-0.3Na alloy from casting to extrusion at either 623 K or 723 K (350 _C or 450 _C) followed by artificial aging at 473 K (200 _C). In particular, the partitioning of Na was examined at each step using STEM-EDS mapping. Na atoms were found to preferentially partition to the Mg-Zn phase when present. After extrusion, when no Mg-Zn was observed, the spherical Mg2Sn particles were found to be enriched in Na, particularly at the higher extrusion temperature. Artificial aging following extrusion resulted in a change in Na partitioning, and a coarse distribution of Mg-Zn precipitate rods. Na microadditions led to a high as-extruded hardness, but a significant tension–compression yield asymmetry was still observed at room temperature. The compressive yield strength was found to decrease significantly after 1000 hours of aging.

Institutional Ownership, Audit Committee and Risk Disclosure – Evidence from Australian Stock Market

This study investigates the influence of institutional ownership and audit committees corporate risk disclosures. Focusing on analysing firms’ risk disclosures make in their 2009 annual reports, our sample constitutes a sample of 66 Australian listed firms. We divide institutional shareholders into dedicated-type institutional block shareholders and transient-type institutional block shareholders. We find that while there is no significant relationship between dedicated-type institutional block shareholders and risk disclosure, there is a positive relationship between transient-type institutional block shareholders and risk disclosures. Our result is consistent with a principal that wields limited monitoring resources while achieving high resource dependency over management. We also find a significant and positive relationship between audit committee independence and risk disclosures, showing the positive role played by audit committee in improving the information transparency and reducing information asymmetry in capital market.

Interviewing pairs: discussions on migration and identity

This article examines a research method of conducting interviews with pairs of individuals, who may be friends or relatives. The authors critically reflect on their experiences of collecting qualitative data in an interview with two respondents. While one-on-one interviews and focus groups are more established and well-studied forms of gathering research data, we argue that paired interviews as a data collections method present additional advantages as well as some challenges for qualitative researchers. The researchers embraced the opportunity to interview pairs of individuals with the intention of minimising the asymmetry of power habitually inherent in interview situations. In the authors' experiences, paired interviews served to empower those being interviewed and reduced the discomfort felt by some in the personal interview situation. This form of interviewing tended to give more autonomy to the respondents and prompted them to provide more nuanced responses. Paired interviews assisted respondents in feeling relaxed and comfortable, provided a vibrant environment that encouraged respondents to build on each other's ideas and enabled them to enhance each other's stories. Respondents were better motivated to build discussions around an interview question and then illustrate their responses with examples. In our studies, we found that our respondents tended to offer more thorough and comprehensive narratives in the setting of a paired interview.