40Ar/39Ar constraints on a temporal link between gold mineralization, magmatism, and continental margin transtension in the Jiaodong Gold Province, eastern China

The Jiaodong gold province is the largest gold repository in China. Both mineralization and granitoid hosts are spatially related to the crustal-scale Tan-Lu strike-slip fault system, which developed along the Mesozoic continental margin in eastern China. A series of Ar-40/Ar-39 laser incremental heating analyses of hydrothermal sericite/muscovite from three major gold deposits (Jiaojia, Xincheng, and Wangershan) and igneous biotite from the granodiorite hosts were performed to establish a possible temporal link between gold mineralization, magmatism, and movement along the Tan-Lu fault zone. Magmatic biotite crystals yield well-defined and concordant plateau ages between 124.5+/-0.4 Ma and 124.0+/-0.4 Ma (2sigma), whereas sericite and muscovite samples (a total of 30 single separates) give reproducible plateau ages ranging from 121.0+/-0.4 Ma to 119.2+/-0.2 Ma (2sigma). An integration of our Ar-40/Ar-39 results with age data from other major gold deposits in Jiaodong demonstrates that widespread gold mineralization occurred contemporaneously during a 2-3-m.yr. period. Most gold deposits show intimate spatial associations with abundant mafic to intermediate dikes. The mafic dikes have K-Ar ages of 123.5-119.6 Ma, in excellent agreement with those of the gold deposits. These newly obtained Ar-40/Ar-39 ages, in combination with other independent geological and geochronological data on granodioritic intrusions (130-126 Ma), volcanic rocks (1243.6-114.7 Ma), and deformed rocks within strike-slip faults (132-120 Ma) in Jiaodong or adjacent areas, also support the idea that gold mineralization postdated the granodioritic magmatism but was contemporaneous with mafic magmatism and volcanism, all controlled by the transtensional motion along the Tan-Lu fault in the Early Cretaceous.

Flavonoids in Australian Melaleuca, Guioa, Lophostemon, Banksia and Helianthus honeys and their potential for floral authentication

Flavonoids in Australian honeys from five botanical species (Melaleuca, Guioa, Lophostemon, Banksia and Helianthus) have been analyzed in relation to their floral origins. Tea tree (Melaleuca quinquenervia) and heath (Banksia ericifolia) honeys show a common flavonoid profile comprising myricetin (3,5,7,3',4',5'-hexahydroxyflavone), tricetin (5,7,3',4,5'-pentahydroxyflavone), querectin (3,5,7,3',4'-pentahydroxyflavone) and luteolin (5,7,3',4'-tetrahydroxyflavone), which was previously suggested as a floral marker for an Australian Eucalyptus honey (bloodwood or Eucalyptus intermedia honey). These honeys of various floral species can be differentiated by their levels of total flavonoids, being 2.12 mg/100 g for heath honey and 6.35 m/100 g for tea tree honey. In brush box (Lophostemon conferta) honey, the flavonoid profile comprising mainly tricetin, luteolin and quercetin is similar to that of another Eucalyptus honey (yellow box or Eucalyptus melliodora honey). These results indicate that the flavonoid profiles in some of the Australian non-Eucalyptus honeys may contain more or less certain flavonoids from Eucalyptus floral sources because of the diversity and extensive availability of Eucalyptus nectars for honeybee foraging yearly around or a possible cross contamination of the monofloral honeys during collection, transportation and/or storage. Further analyses are required to differentiate and/or verify the botanical sources of the flavonoids that contribute to the flavonoid profiles of these honeys, by restricting honey sampling areas and procedures, employing other complementary analytical methods (e.g. pollen analysis, sugar profile) and using materials (e.g. nectar) directly sourced from the flowering plant for comparative studies. In Australian crow ash (Guioa semiglauca) honey, myricetin, tricetin, quercetin, luteolin and an unknown flavonoid have been found to be the main flavonoids, which is characteristic only to this type of honey, and could thus be used as the floral marker, while in Australian sunflower (Helianthus annuus) honey, the content of total flavonoids is the smallest amount comparing to those in the other honeys analysed in this study. However, the flavonoid quercetin and the flavonoid profile mainly consisting of quercetin, quercetin 3,3'-dimethyl ether (5,7,4'-trihydroxy3,3'-dimethoxyflavone), myricetin and luteolin are characteristic only to this sunflower honey and could thus be used for the authentication.

Genetic variability of Tomato spotted wilt virus in Australia and validation of real time RT-PCR for its detection in single and bulked leaf samples

The potential for large-scale use of a sensitive real time reverse transcription polymerase chain reaction (RT-PCR) assay was evaluated for the detection of Tomato spotted wilt virus (TSWV) in single and bulked leaf samples by comparing its sensitivity with that of DAS-ELISA. Using total RNA extracted with RNeasy (R) or leaf soak methods, real time RT-PCR detected TSWV in all infected samples collected from 16 horticultural crop species (including flowers, herbs and vegetables), two arable crop species, and four weed species by both assays. In samples in which DAS-ELISA had previously detected TSWV, real time RT-PCR was effective at detecting it in leaf tissues of all 22 plant species tested at a wide range of concentrations. Bulk samples required more robust and extensive extraction methods with real time RT-PCR, but it generally detected one infected sample in 1000 uninfected ones. By contrast, ELISA was less sensitive when used to test bulked samples, once detecting up to I infected in 800 samples with pepper but never detecting more than I infected in 200 samples in tomato and lettuce. It was also less reliable than real time RT-PCR when used to test samples from parts of the leaf where the virus concentration was low. The genetic variability among Australian isolates of TSWV was small. Direct sequencing of a 587 bp region of the nucleoprotein gene (S RNA) of 29 isolates from diverse crops and geographical locations yielded a maximum of only 4.3% nucleotide sequence difference. Phylogenetic analysis revealed no obvious groupings of isolates according to geographic origin or host species. TSWV isolates, that break TSWV resistance genes in tomato or pepper did not differ significantly in the N gene region studied, indicating that a different region of the virus genome is responsible for this trait.

Clinical features and management of tumors affecting the lacrimal drainage apparatus

Purpose: To report the clinical features of a series of patients with lacrimal drainage apparatus tumors and present guidelines for management based on histopathology. Methods: A noncomparative retrospective chart review of the clinical, imaging, and pathologic findings of 37 patients presenting to four regional orbital Surgery departments with tumors affecting the lacrimal drainage apparatus between 1990 and 2004. Results: There were 37 patients, of whom 62% were male. The mean age at referral was 54 years. Epiphora, a palpable mass, and dacryocystitis were the most common presentations. Two thirds of the tumors were epithelial. with carcinomas being the most frequent (38%). followed by papillomas (27%). Lymphomas were the most common nonepithelial malignancy (30%). Epithelial tumors were more common in men (87%), whereas lymphomas were more common in women (57%). Treatment modalities included surgery, in addition to radiotherapy and/or chemotherapy and immunotherapy. Mean follow-up was 38 months. Thirty-three patients (89%) remain alive without evidence of disease and 4 patients died of recurrence and/or metastases. Conclusions: Lacrimal drainage apparatus tumors require careful initial management to ensure adequate local and systemic disease control. Atypical mucosa encountered during dacryocystorhinostomy should be biopsied and small papillomas or pedunculated tumors excised and analyzed with frozen sections. If a diffuse or infiltrative mass is encountered, it should be biopsied and managed on the basis of histopathology and extent of disease. Lymphomas should be treated according to protocols. whereas noninvasive carcinoma and extensive papillomas require complete excision of the system. Invasive disease requires en bloc excision. Long-term follow-up is essential for early detection of recurrence.

Environmentalizing economic development: a South Asian perspective

South Asia's pursuit of economic development has entailed considerable damage to and exposed the fragility of the physical environment of the region. This paper provides an analytical overview of the of the environmental problem that manifest themselves in South Asia in a comparative perspective with East and Southeast Asian countries as well as selected developed market economics. To date, South Asian development process has been environment-intensive and environment-depleting. It is argued that environmental problems are likely to set serious constraints to sustain growth in production to support a growing population. By exploring the relationship between indices of human welfare and bio-diversity conservation. the paper exposes the dichotomy of the development process. Finally, the study underscores the need for a range of policy options that rely both based and non-market based instruments in an integrated setting to enviromnentalize South Asian economic development. (C) 2004 Elsevier B.V All rights reserved.

Opsins: Evolution in waiting

Complete vertebrate genome sequencing has revealed a remarkable stability and uniformity in the protein-coding gene set, which at first glance might suggest that gene duplication events are relatively rare. This may be a red herring, or at least a red cichlid, as the Lake Malawi cichlid fishes show rapid and extensive duplication and diversification of their retinal cone photoreceptor opsin genes.

Identifying critical components during information security evaluations

Electronic communications devices intended for government or military applications must be rigorously evaluated to ensure that they maintain data confidentiality. High-grade information security evaluations require a detailed analysis of the device's design, to determine how it achieves necessary security functions. In practice, such evaluations are labour-intensive and costly, so there is a strong incentive to find ways to make the process more efficient. In this paper we show how well-known concepts from graph theory can be applied to a device's design to optimise information security evaluations. In particular, we use end-to-end graph traversals to eliminate components that do not need to be evaluated at all, and minimal cutsets to identify the smallest group of components that needs to be evaluated in depth.

Random vibration of the functionally graded laminates in thermal environments

This work deals with the random free vibration of functionally graded laminates with general boundary conditions and subjected to a temperature change, taking into account the randomness in a number of independent input variables such as Young's modulus, Poisson's ratio and thermal expansion coefficient of each constituent material. Based on third-order shear deformation theory, the mixed-type formulation and a semi-analytical approach are employed to derive the standard eigenvalue problem in terms of deflection, mid-plane rotations and stress function. A mean-centered first-order perturbation technique is adopted to obtain the second-order statistics of vibration frequencies. A detailed parametric study is conducted, and extensive numerical results are presented in both tabular and graphical forms for laminated plates that contain functionally graded material which is made of aluminum and zirconia, showing the effects of scattering in thermo-clastic material constants, temperature change, edge support condition, side-to-thickness ratio, and plate aspect ratio on the stochastic characteristics of natural frequencies. (c) 2005 Elsevier B.V. All rights reserved.

Small-scale randomized controlled trials need more powerful methods of mediational analysis than the Baron-Kenny method

Objective: To devise more-effective physical activity interventions, the mediating mechanisms yielding behavioral change need to be identified. The Baron-Kenny method is most commonly used. but has low statistical power and May not identify mechanisms of behavioral change in small-to-medium size Studies. More powerful statistical tests are available, Study Design and Setting: Inactive adults (N = 52) were randomized to either a print or a print-plus-telephone intervention. Walking and exercise-related social support Were assessed at baseline, after file intervention, and 4 weeks later. The Baron-Kenny and three alternative methods of mediational analysis (Freedman-Schatzkin; MacKinnon et al.: bootstrap method) were used to examine the effects of social support on initial behavior change and maintenance. Results: A significant mediational effect of social support on initial behavior change was indicated by the MacKinnon et al., bootstrap. and. marginally. Freedman-Schatzkin methods, but not by the Baron-Kenny method. No significant mediational effecl of social support on maintenance of walking was found. Conclusions: Methodologically rigorous intervention studies to identify mediators of change in physical activity are costly and labor intensive, and may not be feasible with large samples. The Use of statistically powerful tests of mediational effects in small-scale studies can inform the development of more effective interventions. (C) 2006 Elsevier Inc. All rights reserved.

A bloom of Lyngbya majuscula in Shoalwater Bay, Queensland, Australia: An important feeding ground for the green turtle (Chelonia mydas)

Lyngbya majuscula, a toxic cyanobacterium, was observed blooming during June-July (winter) 2002 in Shoalwater Bay, Queensland, Australia, an important feeding area for a large population of green turtles (Chelonia mydas). The bloom was mapped and extensive mats of L majuscula were observed overgrowing seagrass beds along at least 18 km of coast, and covering a surface area of more than I I km(2). Higher than average rainfall preceded the bloom and high water temperatures in the preceding summer may have contributed to the bloom. In bloom samples, lyngbyatoxin A (LA) was found to be present in low concentration (26 mu g kg(-1) (dry weight)), but debromoaplysiatoxin (DAT) was not detected. The diet of 46 green turtles was assessed during the bloom and L. majuscula was found in 51% of the samples, however, overall it contributed only 2% of the animals' diets. L. majuscula contribution to turtle diet was found to increase as the availability of the cyanobacterium increased. The bloom appeared to have no immediate impact on turtle body condition, however, the presence of a greater proportion of damaged seagrass leaves in diet in conjunction with decreases in plasma concentrations of sodium and glucose could suggest that the turtles may have been exposed to a Substandard diet as a result of the bloom. This is the first confirmed report of L. majuscula blooming in winter in Shoalwater Bay, Queensland, Australia and demonstrates that turtles consume the toxic cyanobacterium in the wild, and that they are potentially exposed to tumour promoting compounds produced by this organism. (c) 2005 Elsevier B.V. All rights reserved.

Insulin sensitivity measures in cats exhibit high inter-day variability

In cats with underlying low insulin sensitivity, obesity is a major risk factor for type 2 diabetes. Strategies to prevent the onset of type 2 diabetes could be implemented if these cats could be identified. Currently, two labour-intensive and complex methods have been used to measure insulin sensitivity in research studies: the hyperinsulinemic euglycemic clamp (Clamp) and the minimal model analysis (MINMOD) of a frequentlysampled intravenous glucose tolerance test. However, simpler measures are required in practice. Validation of simple measures requires a wellestablished method with minimal inter-day variability. The aims of this study were to determine the inter-day variability of the current methods of measuring insulin sensitivity in cats, and to assess the relationship between these tests and simpler measures of insulin sensitivity.

Anterior lamella actinic changes as a factor in involutional eyelid malposition

Purpose: We conducted a noncomparative, retrospective chart review of 45 patients and 51 eyelids with the diagnosis of involutional entropion or ectropion that underwent full-thickness lower eyelid shortening between June 2001 and February 2004, in whom the severity of actinic damage was analyzed in relation to the eyelid position. Patients with any different surgical approach or other primary causes of abnormal eyelid position, such as paralytic, congenital, or mechanical factors, were excluded. Methods: After excision, all eyelid specimens were examined by a single anatomic pathologist, who was masked to the type of eyelid malposition. The extent of dermal actinic change was evaluated under light microscopy, according to a previously validated grading system. Results: Fifty-one eyelids from 26 male and 19 female patients were analyzed. The mean age at the surgery was 76 +/- 10 years (range, 52 to 92 years), affecting one side in 39 cases and both sides in 6 cases. The most frequent eyelid malposition was ectropion, which affected two thirds of the cases (35 eyelids). Half of the patients presented with mild actinic skin changes; however, the severity of the histologic skin actinic changes was significantly worse in patients with ectropion in comparison to those with entropion (p < 0.0001). Conclusions: Actinic damage affecting the anterior lamella of the lower eyelid contributes as an additional factor in final eyelid position in patients with involutional eyelid changes. More severe and extensive actinic changes were present in eyelids with ectropion.

Volcanic setting of the Bajo de la Alumbrera porphyry Cu-Au deposit, Farallon Negro Volcanics, Northwest Argentina

The late Miocene Farallon Negro volcanics, comprising basaltic to rhyodacitic volcano-sedimentary rocks, host the Bajo de la Alumbrera porphyry copper-gold deposit in northwest Argentina. Early studies of the geology of the district have underpinned the general model for porphyry ore deposits where hydrothermal alteration and mineralization develop in and around porphyritic intrusions emplaced at shallow depths (2.5-3.5 km) into stratovolcanic assemblages. The Farallon Negro succession is dominated by thick sequences of volcano-sedimentary breccias, with lavas forming a minor component volumetrically. These volcaniclastic rocks conformably overlie crystalline basement-derived sedimentary rocks deposited in a developing foreland basin southeast of the Puna-Altiplano plateau. Within the Farallon Negro volcanics, volcanogenic accumulations evolved from early mafic to intermediate and silicic compositions. The younger and more silicic rocks are demonstrably coeval and comagmatic with the earliest group of mineralized porphyritic intrusions at Bajo de la Alumbrera. Our analysis of the volcanic stratigraphy and facies architecture of the Farallon Negro volcanics indicates that volcanic eruptions evolved from effusive to mixed effusive and explosive styles, as magma compositions changed to more intermediate and silicic compositions. Air early phase of mafic to intermediate voleanism was characterized by small synsedimentary intrusions with peperitic contacts, and lesser lava units scattered widely throughout the district, and interbedded with thick and extensive successions of coarse-grained sedimentary breccias. These sedimentary breccias formed from numerous debris- and hyperconcentrated flow events. A later phase of silicic volcanism included both effusive eruptions, forming several areally restricted lavas, and explosive eruptions, producing more widely dispersed (up to 5 kin) tuff units, some tip to 30-m thickness in proximal sections. Four key features of the volcanic stratigraphy suggest that the Farallon Negro volcanics need not simply record the construction of a large steep-sided polygenetic stratovolcano: (1) sheetlike, laterally continuous debris-flow and other coarse-grained sedimentary deposits are dominant, particularly in the lower sections; (2) mafic-intermediate composition lavas are volumetrically minor; (3) peperites are present throughout the sequence; and (4) fine-grained lacustrine sandstone-siltstone sequences occur in areas previously thought to be proximal to the summit region of the stratovolcano. Instead, the nature, distribution, and geometry of volcanic and volcaniclastic facies suggest that volcanism occurred as a relatively low relief, multiple-vent volcanic complex at the eastern edge of a broad, > 200-km-wide late Miocene volcanic belt and oil ail active foreland sedimentary basin to the Puna-Altiplano. Volcanism that occurred synchronously with the earliest stages of porphyry-related mineralization at Bajo de la Alumbrera apparently developed in an alluvial to ring plain setting that was distal to larger volcanic edifices.

High nuclear genetic diversity, high levels of outcrossing and low differentiation among remnant populations of Quercus petraea at the margin of its range in Ireland

Background and Aims Quercus petraea colonized Ireland after the last glaciation from refugia on mainland Europe. Deforestation. however. beginning in Neolithic times, has resulted in small, scattered forest fragments, now covering less than 12 000 ha. Methods Plastid (three fragments) and microsatellite variation (13 loci) were characterized in seven Irish populations sampled along a north-south gradient. Using Bayesian approaches and Wright's F-statistics, the effects of colonization and fragmentation on the genetic structure and mating patterns of extant oak populations were investigated. Key-Results All Populations possessed cytotypes common to the Iberian Peninsula. Despite the distance from the refugial core and the extensive deforestation in Ireland, nuclear genetic variation was high and comparable to mainland Europe. Low population differentiation was observed within Ireland and populations showed no evidence for isolation by distance. As expected of a marker with an effective Population size of one-quarter relative to the nuclear genome, plastid variation indicated higher differentiation. Individual inbreeding coefficients indicated high levels of outcrossing. Conclusions Consistent with a large effective Population size in the historical migrant gene pool and/or with high gene flow among populations, high within-population diversity and low population differentiation was observred within Ireland. It is proposed that native Q. petraea populations in Ireland share a common phylogeographic history and that the present genetic structure does not reflect founder effects. (C) 2004 Annals of Botany Company.