Late Quaternary Milankovitch-scale climatic change and variability and its impact on monsoonal Australasia

Four pollen and charcoal records derived from marine cores around the northern perimeter of Australia are examined to provide a regional picture of patterns, causes and impacts of climate change over the last 100-300 ka. The availability of radiocarbon dates and oxygen isotope records for the cores provides primary chronological control. Spectral analysis of components of these records demonstrates an overall importance of Milankovitch frequencies with clear glacial-interglacial cyclicity dominated by variation in precipitation. In addition, a number of pollen taxa, as well as charcoal particles, exhibit a 30 ka frequency that is considered, from its relationship with biomass burning and with results of past modelling, to reflect changes in the intensity of El Nino-Southern Oscillation (ENSO) variability. Pollen components of all records show a decline, frequently stepwise, in more fire-sensitive vegetation and its replacement with more fire-tolerant vegetation. There is some evidence that this trend is linked to an onset or general increase in ENSO activity and perhaps also to variation in monsoon activity dating from about 300 ka BP that was caused by changes to oceanic circulation within the Indonesian region. The trend may have accelerated within the last 45 ka due to burning by indigenous people. (C) 2003 Elsevier B.V. All rights reserved.

Apiomorpha gullanae sp n., an unusual new species of gall-inducing scale insect (Hemiptera : Eriococcidae)

An unusual new species of the gall-inducing scale insect genus Apiomorpha Rubsaamen is described from Queensland. The adult female, its gall, and the first-instar nymph (crawler) are illustrated, and relationships of the new species are estimated using mitochondrial COII data. Adult females induce cigar-shaped galls on leaves of several eucalypts in section Adnataria of subgenus Symphyomyrtus. The bilobed anal lobes of the adult female differ from those of all other Apiomorpha species (single lobe) and the first-instar nymph possesses features, such as broad frontal tubercles and dorsal stripes, that are not present in crawlers of other Apiomorpha species. However, DNA sequence data confirm that the new species falls within Apiomorpha, rather than representing a sister group, and indicate that the new species is not closely related to the A. pharetrata (Schrader) species-group, the only other group within Apiomorpha that induces cigar-shaped galls on leaves. The systematic affiliations of A. gullanae sp. n. are currently not known. Females only are known and there is some indication that reproduction in the new taxon is parthenogenetic. This represents the first putative case of parthenogenesis in Apiomorpha.

Hierarchical risk scale of agribusiness activities

This study aims to elaborate a hierarchical risk scale (HRS) of agricultural and cattle breeding activities and to classify the main agricultural crops and cattle breeding activities according to their risk levels. The research is characterized as exploratory and quantitative and was based on previous risk assessment (MARKOWITZ, 1952) and capital cost calculation (SHARPE, 1964) work for other business segments. The calculations on agricultural and cattle breeding data were processed for the period from 2000 to 2006. The used methods considers simplifications and adaptations needed to achieve the proposed objective. The final result, pioneering and embryonic, provides support to improve the management of these activities that are so essential to produce food for society.

The gall-inducing habit has evolved multiple times among the eriococcid scale insects (Sternorrhyncha : Coccoidea : Eriococcidae)

The habit of inducing plant galls has evolved multiple times among insects but most species diversity occurs in only a few groups, such as gall midges and gall wasps. This phylogenetic clustering may reflect adaptive radiations in insect groups in which the trait has evolved. Alternatively, multiple independent origins of galling may suggest a selective advantage to the habit. We use DNA sequence data to examine the origins of galling among the most speciose group of gall-inducing scale insects, the eriococcids. We determine that the galling habit has evolved multiple times, including four times in Australian taxa, suggesting that there has been a selective advantage to galling in Australia. Additionally, although most gall-inducing eriococcid species occur on Myrtaceae, we found that lineages feeding on Myrtaceae are no more likely to have evolved the galling habit than those feeding on other plant groups. However, most gall-inducing species-richness is clustered in only two clades (Apiomorpha and Lachnodius + Opisthoscelis), all of which occur exclusively on Eucalyptus s.s. The Eriococcidae and the large genus Eriococcus were determined to be non-monophyletic and each will require revision. (C) 2004 The Linnean Society of London.

Coronary CT angiography using 64 detector rows: methods and design of the multi-centre trial CORE-64

Multislice computed tomography (MSCT) for the noninvasive detection of coronary artery stenoses is a promising candidate for widespread clinical application because of its non-invasive nature and high sensitivity and negative predictive value as found in several previous studies using 16 to 64 simultaneous detector rows. A multi-centre study of CT coronary angiography using 16 simultaneous detector rows has shown that 16-slice CT is limited by a high number of nondiagnostic cases and a high false-positive rate. A recent meta-analysis indicated a significant interaction between the size of the study sample and the diagnostic odds ratios suggestive of small study bias, highlighting the importance of evaluating MSCT using 64 simultaneous detector rows in a multi-centre approach with a larger sample size. In this manuscript we detail the objectives and methods of the prospective ""CORE-64"" trial (""Coronary Evaluation Using Multidetector Spiral Computed Tomography Angiography using 64 Detectors""). This multi-centre trial was unique in that it assessed the diagnostic performance of 64-slice CT coronary angiography in nine centres worldwide in comparison to conventional coronary angiography. In conclusion, the multi-centre, multi-institutional and multi-continental trial CORE-64 has great potential to ultimately assess the per-patient diagnostic performance of coronary CT angiography using 64 simultaneous detector rows.

Portuguese version of the Delirium Rating Scale-Revised-98: reliability and validity

Objective To assess the validity and the reliability of the Portuguese version of the Delirium Rating Scale-Revised-98 (DRS-R-98). Methods The scale was translated into Portuguese and back-translated into English. After assessing its face validity, five diagnostic groups (n = 64; delirium, depression, dementia, schizophrenia and others) were evaluated by two independent researchers blinded to the diagnosis. Diagnosis and severity of delirium as measured by the DRS-R-98 were compared to clinical diagnosis, Mini-Mental State Exam, Confusion Assessment Method, and Clinical Global Impressions scale (CGI). Results Mean and rnedian DRS-R-98 total scores significantly distinguished delirium from the other groups (p < 0.001). Inter-rater reliability (ICC between 0.9 and 1) and internal consistency (alpha = 0.91) were very high. DRS-R-98 severity scores correlated highly with the CGI. Mean DRS-R-98 severity scores during delirium differed significantly (p < 0.01) from the post-treatment values. The area under the curve established by ROC analysis was 0.99 and using the cut-off Value of 20 the scale showed sensitivity and specificity of 92.6% and 94.6%, respectively. Conclusion The Portuguese version of the DRS-R-98 is a valid and reliable measure of delirium that distinguishes delirium from other disorders and is sensitive to change in delirium severity, which may be of great value for longitudinal studies. Copyright (c) 2007 John Wiley & Sons, Ltd.

Three-dimensional model for multi-component reactive transport with variable density groundwater flow

PHWAT is a new model that couples a geochemical reaction model (PHREEQC-2) with a density-dependent groundwater flow and solute transport model (SEAWAT) using the split-operator approach. PHWAT was developed to simulate multi-component reactive transport in variable density groundwater flow. Fluid density in PHWAT depends not on only the concentration of a single species as in SEAWAT, but also the concentrations of other dissolved chemicals that can be subject to reactive processes. Simulation results of PHWAT and PHREEQC-2 were compared in their predictions of effluent concentration from a column experiment. Both models produced identical results, showing that PHWAT has correctly coupled the sub-packages. PHWAT was then applied to the simulation of a tank experiment in which seawater intrusion was accompanied by cation exchange. The density dependence of the intrusion and the snow-plough effect in the breakthrough curves were reflected in the model simulations, which were in good agreement with the measured breakthrough data. Comparison simulations that, in turn, excluded density effects and reactions allowed us to quantify the marked effect of ignoring these processes. Next, we explored numerical issues involved in the practical application of PHWAT using the example of a dense plume flowing into a tank containing fresh water. It was shown that PHWAT could model physically unstable flow and that numerical instabilities were suppressed. Physical instability developed in the model in accordance with the increase of the modified Rayleigh number for density-dependent flow, in agreement with previous research. (c) 2004 Elsevier Ltd. All rights reserved.

The systematics and biology of the south African gall-inducing scale insect, Calycicoccus merwei brain (Hemiptera : Coccoidea : Eriococcidae)

The scale insect genus Calycicoccus Brain has a single described species, C. merwei Brain, which is endemic to southeastern South Africa. Females of C. merwei induce small, mostly conical galls on the foliage of their host tree, Apodytes dimidiata E. Meyer ex Arn. (Icacinaceae), which has a wider, mostly coastal distribution, than that currently known for the scale insect. Calycicoccus has been placed in the family Eriococcidae and may be related to the South American genus Aculeococcus Lepage. No other native eriococcid species have been described so far in South Africa, although the family is diverse in other Gondwanan regions. This paper summarizes the biology of C. merwei, redescribes the adult female, describes the adult male, the second-instar female and the first-instar nymphs for the first time, and reconsiders the phylogenetic relationships of the genus. The adult female is shown to have unusual abdominal segmentation, in that segment I is present both dorsally and ventrally, but a segment is absent ventrally on the middle abdomen. First-instar nymphs are sexually dimorphic; males have a larger and relatively narrower body, larger mouthparts, longer antennae and legs, and more thoracic dorsal setae compared with females. Molecular data from nuclear small-subunit ribosomal DNA (18S) and elongation factor 1 alpha (EF-1a) show C. merwei to have no close relatives among the Eriococcidae sampled to date. Instead, the Calycicoccus lineage is part of a polytomy near the base of the Eriococcidae. Molecular dating of the node suggests that the Calycicoccus lineage diverged from other eriococcids more than 100 Mya. These data support the placement of Calycicoccus as the only genus in the subfamily Calycicoccinae Brain.

Spatial distribution of pink wax scale, Ceroplastes rubens Maskell (Hemiptera: Coccidae), on umbrella trees in south-eastern Queensland: The pattern of outbreaks

The spatial pattern of outbreaks of pink wax scale, Ceroplastes rubens Maskell, within and among umbrella trees, Schefflera actinophylla (Endl.), in southeastern Queensland was investigated. Pink wax scale was common on S. actinophylla, with approximately 84% of trees positive for scale and 14% of bees recording outbreak densities exceeding 0.4 adults per leaflet. Highly aggregated distributions of C. rubens occur within and among umbrella trees. Clumped distributions within trees appear to result from variable birth and death rates and limited movement of first instar crawlers. The patchy distribution of pink wax scale among trees is probably a consequence of variation in dispersal success of scale, host and environmental suitability for establishment and rates of biological control. Pink wax scale was more prevalent on trees in roadside positions and in exposed situations, indicating that such trees are more suitable and/or susceptible to scale colonisation.