University of Canterbury

About: University of Canterbury is a education organization based out in Christchurch, New Zealand. It is known for research contribution in the topics: Population & Large Hadron Collider. The organization has 11100 authors who have published 29846 publications receiving 893232 citations. The organization is also known as: Te Whare Wānanga o Waitaha & Canterbury College.

Risk‐related disclosures by non‐finance companies: Portuguese practices and disclosure characteristics

Abstract: Purpose – The purpose of this paper is to assess the risk‐related disclosure (RRD) practices in annual reports for 2005 Portuguese companies in the non‐finance sector.Design/methodology/approach – The paper conducts a content analysis of a sample of 81 companies (42 listed and 39 unlisted). In considering corporate governance effects, the sample is reduced to the 42 listed companies that are required to disclose a corporate governance report.Findings – Implementation of IAS/IFRS and the European Union's Modernisation Directive in 2005 did not affect the quantity and quality of RRD positively. Disclosures are generic, qualitative and backward‐looking. Public visibility (as assessed by size and environmental sensitivity) is a crucial influence in explaining RRD: companies appear to manage their reputation through disclosure of risk‐related information. Agency costs associated with leverage are important influences also. In listed companies, the presence of independent directors improves the level of RRD.Res...

Detection of Rotation in a Binary Microlens: PLANET Photometry of MACHO 97-BLG-41*

Abstract: We analyze PLANET collaboration data for MACHO 97-BLG-41, the only microlensing event observed to date in which the source transits two disjoint caustics. The PLANET data, consisting of 46 V -band and 325 I-band observations from —ve southern observatories, span a period from the initial alert until the end of the event. Our data are incompatible with a static binary lens, but are well —tted by a rotating binary lens of mass ratio q \ 0.34 and angular separation d B 0.5 (in units of the Einstein ring radius), in which the binary separation changes in size by dd \( 0.070 ^ 0.009 and in orientation by during the 35.17 days between the separate caustic transits. We use this measurement, dh \ 5i.61^ 0i.36 combined with other observational constraints, to derive the —rst kinematic estimate of the mass, dis- tance, and period of a binary microlens. The relative probability distributions for these parameters peak at a total lens mass M D 0.3 (M-dwarf binary system), lens distance kpc, and binary period M _ D L D 5.5 P D 1.5 yr. The robustness of our model is demonstrated by its striking agreement with MACHO/ GMAN data that cover several sharp features in the light curve not probed by the PLANET obser- vations, and which did not enter our modeling procedure in any way. Available data sets thus indicate that the light curve of MACHO 97-BLG-41 can be modeled as a source crossing two caustics of a physi- cally realistic rotating binary. Thus, contrary to a recent suggestion, the additional eUects of a postulated planetary companion to the binary lens are not required. Subject headings: binaries: generalgravitational lensingplanetary systems

Evaluating the wind pollination benefits of mast seeding

Abstract: We developed a conceptual model for evaluating the benefits of wind pollination to mast-flowering species. The benefit that a plant population gains from mast flowering via increased wind pollination efficiency was predicted from how far pollination efficiency at mean seed crop size falls below the maximum. Species were most likely to benefit from mast seeding if mean reproductive effort in the field gave an intermediate level of pollination efficiency, regardless of the cost of unpollinated female structures. To quantify the benefits of different degrees of mast flowering, a simulation model was used to alter the seed production coefficient of variation (cv) and to calculate its effects on weighted mean pollination efficiency. The model was applied to seven real data sets for five species with pollination benefits from masting that ranged from relatively small (Chionochloa pallens), to moderate (Dacrydium cupressinum, Betula alleghaniensis), to large (Nothofagus solandri, N. menziesii). Many studies have reported higher seed production coefficients of variation at higher altitudes and latitudes within a species. Our model showed that higher coefficients of variation are favored by reduced mean seed output per plant at higher altitudes. Data for N. solandri at three altitudes in one site showed much higher pollination benefits from masting at higher altitudes. Reduced plant density (e.g., through fragmentation), which also lowers mean flowering effort per unit area, resulted in large increases in masting benefits in N. solandri, but only small increases in C. pallens. These contrasting results were primarily due to differences between the two species in mean reproductive effort vs. wind pollination efficiency, rather than to differences in the effects of fragmentation and altitude. The relative effects of masting on pollination, insect seed predation, and bird seed predation were modeled in B. alleghaniensis. Masting produced a small economy of scale from insect predator satiation, but an almost equivalent diseconomy of scale resulted from increased levels of bird seed predation. Efficiency of wind pollination improved moderately with increasing cv, providing some overall benefits from masting in this species. Accordingly, we propose that masting can be favored by either one dominant economy of scale (such as wind pollination efficiency in N. solandri or predator satiation in C. pallens), or a balance among several factors (such as pollination, predator satiation, and predator attraction in B. alleghaniensis). We predict that, in the absence of any selective benefits or disadvantages of masting, plants would be expected to have coefficients of variation in the range 0.85–1.35.

The History of the Science and Technology of Electrospinning from 1600 to 1995

Abstract: A significant challenge inThis paper outlines the story of the inventions and discoveries that directly relate to the genesis and development of electrostatic production and drawing of fibres: electrospinning. Current interest in the process is due to the ease with which nano-scale fibers can be produced in the laboratory. In 1600, the first record of the electrostatic attraction of a liquid was observed by William Gilbert. Christian Friedrich Schonbein produced highly nitrated cellulose in 1846. In 1887 Charles Vernon Boys described the process in a paper on nano-fiber manufacture. John Francis Cooley filed the first electrospinning patent in 1900. In 1914 John Zeleny published work on the behaviour of fluid droplets at the end of metal capillaries. His effort began the attempt to mathematically model the behavior of fluids under electrostatic forces. Between 1931 and 1944 Anton Formhals took out at least 22 patents on electrospinning. In 1938, N.D. Rozenblum and I.V. Petryanov-Sokolov generated electrospun fibers, which they developed into filter materials. Between 1964 and 1969 Sir Geoffrey Ingram Taylor produced the beginnings of a theoretical underpinning of electrospinning by mathematically modelling the shape of the (Taylor) cone formed by the fluid droplet under the effect of an electric field. In the early 1990s several research groups (notably that of Reneker who popularised the name electrospinning) demonstrated electrospun nano-fibers. Since 1995, the number of publications about electrospinning has been increasing exponentially every year.

Why managers divest—Evidence from New Zealand's largest companies

Abstract: Chief Executives from New Zealand's largest companies were surveyed to distinguish divesting and nondivesting companies, and to identify the relative importance of the factors and motives which led to the divestment of 208 business units in the period 1985 through 1990 The divesting companies were considerably larger and faster growing than nondivestors The typical divestment was motivated by the need to convert unattractive assets into liquid form which could then be held to strengthen the balance sheet, or reinvested in either the core business or new areas