Preliminary observations of insect pollination in Protea punctata (Proteaceae)

AbstractAvailable information on the phylogeny and pollination systems in Protea suggests that bird-pollination is ancestral and occurs in the majority of species, and that there have been several shifts to rodent pollination and a single shift to pollination by cetoniine beetles in this large African genus. Here we report that Protea punctata plants in a population in the Swartberg mountains are pollinated primarily by long-proboscid flies and butterflies. The threadlike pollen presenter on an unusually flexible style facilitates insect pollination in this species. The length of the style matches that of the proboscides of its two most common visitors, the nemestrinid fly Prosoeca longipennis and the nymphalid butterfly Aeropetes tulbaghia. Spectral reflectance of the involucral bracts is similar to that of flowers of other plants visited by long-proboscid flies. P. punctata occupies a recently diverged position in a clade (the “white proteas”) in which all the other species appear to be bird-pollinated, and may represent a shift to insect pollination in the genus

Social structures and entrepreneurial networks: the strength of strong ties.

The entrepreneurial context provides a fertile arena for the study of networks. This qualitative study critically examines the nature, content and process of strong ties, which are found to fall into three categories: family, business contacts, and suppliers, competitors and customers. These nodal categories each provide a specific range of support to the entrepreneur. Their appropriate and effective utilization greatly facilitates enterprise performance

Flow equation analysis of the anisotropic Kondo model

We use the new method of infinitesimal unitary transformations to calculate zero temperature correlation functions in the strong-coupling phase of the anisotropic Kondo model. We find the dynamics on all energy scales including the crossover behaviour from weak to strong coupling. The integrable structure of the Hamiltonian is not used in our approach. Our method should also be useful in other strong-coupling models since few other analytical methods allow the evaluation of their correlation functions on all energy scales.Comment: 4 pages RevTeX, 2 eps figures include

Effect of route of administration of lasalocid on response of young dairy calves

Forty newborn bull calves were assigned to one of four feeding groups. The feeds either contained lasalocid in milk (M), prestarter (PS), and starter (S); lasalocid in PS and S; lasalocid in S only; or no lasalocid. Calves were fed M at 8% of birth weight (bw) daily and offered PS to a maximum of 0.5 lb daily. When 0.5 lb of PS was consumed in one day the calves were fed M at 4% of bw daily. They were weaned when they consumed dry feed at the rate of 1.3% of bw. Daily feed intake and weekly weight gains of calves were evaluated. Blood serum samples were used to evaluate blood metabolites at wk 4, 8, and 12. We concluded that lasalocid in M, PS, and S supported greater feed efficiency and allowed earlier weaning with less animal variation than when lasalocid was delivered in PS and S, only in S, or not at all

Optimal generalization of power filters for gravitational wave bursts, from single to multiple detectors

Searches for gravitational wave signals which do not have a precise model describing the shape of their waveforms are often performed using power detectors based on a quadratic form of the data. A new, optimal method of generalizing these power detectors so that they operate coherently over a network of interferometers is presented. Such a mode of operation is useful in obtaining better detection efficiencies, and better estimates of the position of the source of the gravitational wave signal. Numerical simulations based on a realistic, computationally efficient hierarchical implementation of the method are used to characterize its efficiency, for detection and for position estimation. The method is shown to be more efficient at detecting signals than an incoherent approach based on coincidences between lists of events. It is also shown to be capable of locating the position of the source.Comment: 16 pages, 5 figure

Advisory Intelligent Speed Adaptation for government fleets

This project sought to determine the likely crash savings if state government fleets in Australia were fitted with advisory Intelligent Speed Adaptation (ISA). The cost effectiveness of such a fitment was assessed considering if the ISA device is kept within the government fleet (scenario 1) or if it is left in the government vehicle when it is sold (scenario 2). Data from the fleet vehicles involved in the recent NSW ISA was used. The reduction in crash risk was calculated by applying Kloeden’s risk curves for travel speed to the “before” speed profile and the “ISA active” speed profile found in the trial. The reduction in risk was then estimated in terms of the difference in the total crash risk produced by these speed profiles. ISA was found to have the potential to reduce casualty crashes in government fleets by 20%. It was estimated that this would eliminate 171 casualty crashes involving state government vehicles per year and save $31.6 million in crash costs per year. Scenario 1 was more cost effective than scenario 2, although the wider benefit to the community produced by scenario 2 was not taken into account. Of the four ISA devices considered the navaid device that included ISA functionality was found to be the most cost effective.SD Doecke, RWG Anderson, JE Woolle

Time-frequency detection algorithm for gravitational wave bursts

An efficient algorithm is presented for the identification of short bursts of gravitational radiation in the data from broad-band interferometric detectors. The algorithm consists of three steps: pixels of the time-frequency representation of the data that have power above a fixed threshold are first identified. Clusters of such pixels that conform to a set of rules on their size and their proximity to other clusters are formed, and a final threshold is applied on the power integrated over all pixels in such clusters. Formal arguments are given to support the conjecture that this algorithm is very efficient for a wide class of signals. A precise model for the false alarm rate of this algorithm is presented, and it is shown using a number of representative numerical simulations to be accurate at the 1% level for most values of the parameters, with maximal error around 10%.Comment: 26 pages, 15 figures, to appear in PR

Geotechnical causes for variations in output measured from shallow buried charges

The role of the geotechnical conditions on the impulse delivered by a shallow buried charge has received much attention in recent times. As the importance of the soil in these events has become better understood, the control over the geotechnical conditions has improved. While previous work has investigated directly the role of geotechnical conditions on the magnitude of the impulse from a buried charge, the current work aims to identify how these same conditions also affect the repeatability of testing using soils. In this paper the authors draw together their work to date for a wide range of different soil types and moisture contents to investigate the variation in output from nominally identical tests. The methodology for the preparation of soil beds and the measurement of impulse is described along with the measured variations in peak and residual deflections of a target plate fixed to the impulse measurement apparatus