Physical factors influencing the distribution of a top predator in a subtropical oligotrophic estuary

We used longline fishing to determine the effects of distance from the ocean, season, and short-term variation in abiotic conditions on the abundance of juvenile bull sharks (Carcharhinus leucas) in an estuary of the Florida Everglades, U.S.A. Logistic regression revealed that young-of-the-year sharks were concentrated at a protected site 20 km upstream and were present in greater abundance when dissolved oxygen (DO) levels were high. For older juvenile sharks (age 1+), DO levels had the greatest influence on catch probabilities followed by distance from the ocean; they were most likely to be caught at sites with .3.5 mg L21 DO and on the main branch of the river 20 km upstream. Salinity had a relatively small effect on catch rates and there were no seasonal shifts in shark distribution. Our results highlight the importance of considering DO as a possible driver of top predator distributions in estuaries, even in the absence of hypoxia. In Everglades estuaries hydrological drivers that affect DO levels (e.g., groundwater discharge, modification of primary productivity through nutrient fluxes) will be important in determining shark distributions, and the effects of planned ecosystem restoration efforts on bull sharks will not simply be mediated by changing salinity regimes and the location of the oligohaline zone. More generally, variation in DO levels could structure the nature and spatiotemporal pattern of top predator effects in the coastal Everglades, and other tropical and subtropical estuaries, because of interspecific variation in reliance on DO within the top predator guild.

(Table 3, page 280) Chemical composition of micronodules from a series of stations and sediment depths from Areas C, F, G and K in the Pacific Ocean from R/V Sonne Cruise SO06

Compositional data for coexisting manganese nodules, micronodules, sediments and pore waters from five areas in the equatorial and S.W. Pacific have been obtained. This represents the largest study of its type ever undertaken to establish the distribution of elements between the various phases within the sediment column. The composition of manganese nodules, micronodules and sediments (on a carbonate-free basis) shows marked differences between the equatorial high productivity zone and the low productivity region of the S.W. Pacific. In the case of the nodules, th is reflects an increased supply of transition elements (notably Ni, Cu and Zn) to the nodules as a result of the in situ dissolution of siliceous tests within the sediment column in the equatorial Pacific high productivity zone. Micronodules display similar, but somewhat different, compositions to those of the associated nodules in each area. Micronodule composition is therefore influenced by the same basic factors that control nodule composition, but is modified by dissolution of the micronodules in situ within the sediment column. Locally, as in the area immediately south of the Marquesas Fracture Zone, the micronodule population is contaminated by small, angular volcanic rock fragments; this leads to apparently anomalous micronodule compositions. Micronodules appear to be a transient feature in the sediment column, especially in the equatorial Pacific. Dissolution of micronodules in the sediment column therefore represents an important source of elements for the growth of manganese nodules in the equatorial Pacific. Sediment composition is markedly influenced by the carbonate content. On a carbonate-free basis, the sediments from the equatorial high productivity zone are quite distinct in composition from those in the S.W. Pacific. This reflects differences in the lithology of the sediments. In the Aitutaki Passage, the local influence of volcanoclastic material in sediment composition has been established. The major cations and anions in pore waters measured here show no major differences between equatorial and S.W. Pacific sediments. Silica is, however, higher in equatorial Pacific pore waters reflecting the dissolution of siliceous tests in these sediments.

Towards a single crystal Raman spectrum of kaolinite at 77 K

The Raman spectra at 77 K of the hydroxyl stretching of kaolinite were obtained along the three axes perpendicular to the crystal faces. Raman bands were observed at 3616, 3658 and 3677 cm−1 together with a distinct band observed at 3691 cm−1 and a broad profile between 3695 and 3715 cm−1. The band at 3616 cm−1 is assigned to the inner hydroxyl. The bands at 3658 and 3677 cm−1 are attributed to the out-of-phase vibrations of the inner surface hydroxyls. The Raman spectra of the in-phase vibrations of the inner-surface hydroxyl-stretching region are described in terms of transverse and longitudinal optic splitting. The band at 3691 cm−1 is assigned to the transverse optic and the broad profile to the longitudinal optic mode. This splitting remained even at liquid nitrogen temperature. The transverse optic vibration may be curve resolved into two or three bands, which are attributed to different types of hydroxyl groups in the kaolinite.

From the account manager’s conscience to top-of-mind : account planning in Australia

What began as the “account manager’s conscience” has grown to be top-of-mind in Australian advertising today. Account planning is a hybrid discipline which uses research to bring the consumer voice to the campaign process during strategy generation, creative development and evaluation. In Australia, account planning is subjected to the “Vegemite Factor” where planners are spread too thinly across accounts and much of the market is dominated by freelance researchers and planners. This unique environment has shaped many different perceptions of account planning in Australia. These are compared with an international definition of account planning and the current research. While many basic tenants of the definition are shared by Australian advertising professionals, the difference appears to be in the ongoing nature, team approach and level of commitment. In Australia, account planners seem to be more facilitators of the strategic direction, than directors of it. Instead of exerting a sustained influence across the campaign, most energy appears to be expended at the start of campaign development, rather than extending through to its evaluation.

K-tree : large scale document clustering

We introduce K-tree in an information retrieval context. It is an efficient approximation of the k-means clustering algorithm. Unlike k-means it forms a hierarchy of clusters. It has been extended to address issues with sparse representations. We compare performance and quality to CLUTO using document collections. The K-tree has a low time complexity that is suitable for large document collections. This tree structure allows for efficient disk based implementations where space requirements exceed that of main memory.

The knowledge advantage (K-Adv): unleashing creativity and innovation

The K-Adv has been developed around the concept that it comprises an ICT enabling infrastructure that encompasses ICT hardware and software infrastructure facilities together with an enabling ICT support system; a leadership infrastructure support system that provides the vision for its implementation and the realisation capacity for the vision to be realised; and the necessary people infrastructure that includes the people capabilities and capacities supported by organisational processes that facilitates this resource to be mobilised.

Document clustering with K-tree

This paper describes the approach taken to the XML Mining track at INEX 2008 by a group at the Queensland University of Technology. We introduce the K-tree clustering algorithm in an Information Retrieval context by adapting it for document clustering. Many large scale problems exist in document clustering. K-tree scales well with large inputs due to its low complexity. It offers promising results both in terms of efficiency and quality. Document classification was completed using Support Vector Machines.