Macquarie University

About: Macquarie University is a education organization based out in Sydney, New South Wales, Australia. It is known for research contribution in the topics: Population & Laser. The organization has 14075 authors who have published 47673 publications receiving 1416184 citations. The organization is also known as: Macquarie uni.

National culture and corporate cash holdings around the world

Abstract: This paper examines whether cultural dimensions explain the variation in corporate cash holdings around the world as well as within the United States. We establish four major findings. First, in an international setting, corporate cash holdings are negatively associated with individualism and positively associated with uncertainty-avoidance. Second, individualism and uncertainty avoidance influence the precautionary motive for holding cash. Third, firms in individualistic states in the United States hold less cash than firms in collectivistic states. Fourth, we show that individualism is positively related to the firm’s capital expenditures, acquisitions, and repurchases while uncertainty avoidance is negatively related. Our findings remain unchanged after controlling for governance factors, firm attributes, and country characteristics.

Latitude, seed predation and seed mass

Abstract: Aim We set out to test the hypothesis that rates of pre- and post-dispersal seed predation would be higher towards the tropics, across a broad range of species from around the world. We also aimed to quantify the slope and predictive power of the relationship between seed mass and latitude both within and across species. Methods Seed mass, pre-dispersal seed predation and post-dispersal seed removal data were compiled from the literature. Wherever possible, these data were combined with information regarding the latitude at which the data were collected. Analyses were performed using both cross-species and phylogenetic regressions. Results Contrary to expectations, we found no significant relationship between seed predation and latitude (log10 proportion of seeds surviving predispersal seed predation vs. latitude, P = 0.63; R2 = 0.02; n = 122 species: log10 proportion of seeds remaining after postdispersal seed removal vs. latitude, P = 0.54; R2 = 0.02; n = 205 species). These relationships remained non-significant after variation because of seed mass was accounted for. We also found a very substantial (R2 = 0.21) relationship between seed mass and latitude across 2706 species, with seed mass being significantly higher towards the tropics. Within-species seed mass decline with latitude was significant, but only about two-sevenths, as rapid as the cross-species decline with latitude. Results of phylogenetic analyses were very similar to cross-species analyses. We also demonstrated a positive relationship between seed mass and development time across ten species from dry sclerophyll woodland in Sydney (P < 0.001; R2 = 0.77; Standardized Major Axis slope = 0.14). These data lend support to the hypothesis that growing period might affect the maximum attainable seed mass in a given environment. Main conclusions There was no evidence that seed predation is higher towards the tropics. The strong relationship between seed mass and latitude shown here had been observed in previous studies, but had not previously been quantified at a global scale. There was a tenfold reduction in mean seed mass for every c. 23° moved towards the poles, despite a wide range of seed mass within each latitude.

Tensor network states and algorithms in the presence of a global SU(2) symmetry

Abstract: Tensor network decompositions offer an efficient description of certain many-body states of a lattice system and are the basis of a wealth of numerical simulation algorithms. In a recent paper [Phys. Rev. APLRAAN1050-294710.1103/ PhysRevA.82.050301 82, 050301 (2010)] we discussed how to incorporate a global internal symmetry, given by a compact, completely reducible group G, into tensor network decompositions and algorithms. Here we specialize to the case of Abelian groups and, for concreteness, to a U(1) symmetry, associated, e.g., with particle number conservation. We consider tensor networks made of tensors that are invariant (or covariant) under the symmetry, and explain how to decompose and manipulate such tensors in order to exploit their symmetry. In numerical calculations, the use of U(1)-symmetric tensors allows selection of a specific number of particles, ensures the exact preservation of particle number, and significantly reduces computational costs. We illustrate all these points in the context of the multiscale entanglement renormalization Ansatz.

The Internal Audit Function: Perceptions of Internal Audit Roles, Effectiveness, and Evaluation

Abstract: Purpose: The aim of this exploratory study is to provide insights into the current roles and responsibilities of the internal audit (IA) function and the factors perceived to be necessary to ensure its effectiveness. The current performance evaluation practices of IA are also examined. Design/Methodology/Approach: Semi-structured interviews were utilised to elicit the perceptions of key corporate governance actors about the evolving role of IA, as well as IA effectiveness, in terms of its design, measurement, and evaluation. Findings: The results of the study suggest significant expansion and refocus of the role of IA and perceptions of its effectiveness. However, the findings also suggest that performance evaluation mechanisms of IA have not evolved contemporaneously. The misalignment between the role and evaluation gives rise to difficulty in assessing the extent to which IA functions are meeting stakeholders’ expectations. Practical Implications: The findings are useful in informing the deliberations of regulators and standard setters, as well as providing a benchmark for internal auditors and audit committees. The insights are also relevant for external auditors who are required to consider various aspects of corporate governance, including the objectivity and quality of IA. Originality/Value: The use of semi-structured interviews facilitates an in-depth insight and understanding of the perceptions of roles, effectiveness and evaluation of IA and adds depth to the predominantly questionnaire based survey approach of prior studies.

Drilling to gabbro in intact ocean crust

Abstract: Sampling an intact sequence of oceanic crust through lavas, dikes, and gabbros is necessary to advance the understanding of the formation and evolution of crust formed at mid-ocean ridges, but it has been an elusive goal of scientific ocean drilling for decades. Recent drilling in the eastern Pacific Ocean in Hole 1256D reached gabbro within seismic layer 2, 1157 meters into crust formed at a superfast spreading rate. The gabbros are the crystallized melt lenses that formed beneath a mid-ocean ridge. The depth at which gabbro was reached confirms predictions extrapolated from seismic experiments at modern mid-ocean ridges: Melt lenses occur at shallower depths at faster spreading rates. The gabbros intrude metamorphosed sheeted dikes and have compositions similar to the overlying lavas, precluding formation of the cumulate lower oceanic crust from melt lenses so far penetrated by Hole 1256D.