Since 1970, the worldwide distribution, frequency and intensity of epidemics of dengue and dengue haemorrhagic fever (DHF) have increased dramatically. In Indonesia, as elsewhere, the geographic distribution and behaviour of the two main vectors –Aedes aegypti and Aedes albopictus– and the consequent transmission dynamics of the disease are strongly influenced by climate. Monthly incidence data were examined in relation to monthly data for temperature, rainfall, rainfall anomalies, humidity and the Southern Oscillation Index for 1992–2001. Focusing on eight provinces, significant Pearson correlations were observed between dengue/DHF incidence and at least one climate variable (r = ±0.2 to ±0.43; P < 0.05). Multiple regression analyses showed that 12.9–24.5 per cent of variance in incidence was explained by two or three climate variables in each province (P < 0.1–0.01). Rainfall appears to be the principal climatic agent affecting the geographic distribution and temporal pattern of incidence while temperature appears to play a critical role in outbreak intensity. Wide regional and temporal variations in the strength and nature of the observed associations led to the identification of three groups of provinces where increases in dengue/DHF incidence were variously associated with increased rainfall, decreased rainfall and/or high susceptibility to climate variability. Although climatic factors play an important role in explaining the timing and intensity of dengue/DHF outbreaks, a wide range of other factors specific to local environments also appear to be involved – information that may assist in the prediction and mitigation of regional dengue/DHF outbreaks.

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This research advances the understanding of the location of perceived landscape values through a statistically based approach to spatial analysis of value densities. Survey data were obtained from a sample of people living in and using the Murray River region, Australia, where declining environmental quality prompted a reevaluation of its conservation status. When densities of 12 perceived landscape values were mapped using geographic information systems (GIS), valued places clustered along the entire river bank and in associated National/State Parks and reserves. While simple density mapping revealed high value densities in various locations, it did not indicate what density of a landscape value could be regarded as a statistically significant hotspot or distinguish whether overlapping areas of high density for different values indicate identical or adjacent locations. A spatial statistic Getis-Ord Gi* was used to indicate statistically significant spatial clusters of high value densities or "hotspots". Of 251 hotspots, 40% were for single non-use values, primarily spiritual, therapeutic or intrinsic. Four hotspots had 11 landscape values. Two, lacking economic value, were located in ecologically important river red gum forests and two, lacking wilderness value, were near the major towns of Echuca-Moama and Albury-Wodonga. Hotspots for eight values showed statistically significant associations with another value. There were high associations between learning and heritage values while economic and biological diversity values showed moderate associations with several other direct and indirect use values. This approach may improve confidence in the interpretation of spatial analysis of landscape values by enhancing understanding of value relationships.

Delayed onset heparin-associated thrombocytopenia (HAT) is thought to be a result of formation of antiplatelet antibodies which cause platelet aggregation in the presence of heparin. Platelet aggregation in response to serum from patients with HAT has been studied in platelet-rich plasma (PRP) from a panel of normal blood donors. Heparin-dependent aggregation with any HAT serum occurred in PRP from only some donors. PRP from the non-responding donors did, however, aggregate in the presence of heparin with other HAT sera. The same patterns of aggregation or lack of response to HAT sera were seen in washed platelet suspensions. Heparin (0.06-2 U/ml) did not cause aggregation in the presence of normal serum with PRP from these donors. However, in PRP from four of the 17 individuals studied, heparin (0.25-1 U/ml) alone caused rapid platelet aggregation and some HAT sera heated at 56 degrees C caused platelet aggregation without added heparin. Sub-aggregating concentrations of adrenaline could replace heparin in promoting aggregation by heated HAT sera in PRP of the other donors. HAT IgG showed the same platelet specificities as the serum in causing either heparin- or adrenaline-dependent aggregation. Thus in HAT, antibodies are directed towards different platelet antigens which are expressed differently in different individuals. Platelet activation by heparin and adrenaline either exposes these antigens or causes aggregation of antibody-coated platelets.

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Partnerships between natural-area managers and the tourism industry have been suggested to contribute to sustainability in protected areas. This article explores how important sustainability outcomes of partnerships are to their members, how well they are realised and the features of partnerships leading to their achievement. In 21 case studies in Australia, interviews (n = 97) and surveys (n = 100) showed that of 14 sustainability outcomes, improved understanding of protected areas values and improved biodiversity conservation were the most important. Other highly ranked outcomes were greater respect for culture, heritage, and/or traditions; improved quality of environmental conditions; social benefits to local communities; and improved economic viability of the protected area. Scores for satisfaction with outcomes were, like those for importance, all high but were less than those for importance for the majority, with improvement in quality of environmental conditions showing the largest gap. The satisfaction score exceeded that for importance only for increased competitiveness of the protected area as a tourist destination. “Brown” aspects of sustainability, i.e., decreased waste or energy use, were among the lowest-scoring outcomes for both importance and satisfaction. The most important factor enabling sustainability outcomes was provision of benefits to partnership members. Others were increased financial support, inclusiveness, supportive organisational and administrative arrangements, direct involvement of decision makers, partnership maturity, creation of new relationships, decreased conflict, and stimulation of innovation. Improving sustainability outcomes, therefore, requires maintaining these partnership attributes and also increasing emphasis on reducing waste and resource use.

Previously described platelet-aggregating antibodies associated with thrombosis and thrombocytopenia required heparin for their in vivo and in vitro expression. We have observed a patient with thrombosis who became thrombocytopenic during heparin treatment, but who suffered further thrombotic events and continued thrombocytopenia for 3 months after heparin withdrawal. The patient's plasma contained a potent platelet aggregating factor reactive with both his own and normal platelets in the absence of heparin. It also caused [14C]serotonin secretion from labelled platelets from normal donors and patients with either Glanzmann's thrombasthenia or Bernard-Soulier syndrome. This factor was an IgG and was neutralized by antibody specific for IgG lambda light chains. While the patient was thrombocytopenic an IgG paraprotein with lambda light chains was detected by isoelectrofocussing. After corticosteroid treatment it disappeared and the patient recovered. The active, but not the recovery serum contained IgG which immunoprecipitated a glycoprotein with characteristics of Glycoprotein IV from platelets labelled with Na[3H]BH4/periodate. Thus platelet-aggregating IgG antibodies with direct specificity for platelet surface glycoproteins may be associated with thrombosis/thrombocytopenia.

SummaryThe Gray platelet syndrome is a rare disorder characterised by the absence of platelet a-granules and their contents. We describe a new patient and the effects of infusions of l-deainino-8-aiginine vasopressin (DDAVP). The patient had a prolonged skin bleeding time and his platelets had reduced numbers of a-granules, increased vacuolation and reduced retention on glass beads. Flatelet von Willebrand factor antigen (vWf:Ag) was undetectable and levels of platelet fibrinogen, p-thioniboglobulin, platelet factor 4 and thrombospondin were reduced. All tests of plasma coagulation factors were normal, including Factor VIII (F. VIII: C), vWf: Ag, ristocetin cofactor (R: CoF) and botrocetin cofactor. Platelet ATP, ADP, platelet albumin, surface membrane glycoproteins and 14C-serotonin uptake were also normal. Infusions of DDAVP increased plasma F.VIII:C, vWf:Ag and R.CoF and sliuitened the bleeding time un two occasions. This suggests that DDAVP shortens the bleeding time by releasing vWf: Ag and/or other proteins from cellular storage sites other than the platelet.