The Pseudoreticulatispora confluens-P. pseudoreticulata spore-pollen zonal datum typically coincides with the end of widespread Permian glacial deposits in Western Australia. Although previously ...attributed to the mid-Sakmarian, chemical abrasion isotope dilution thermal ionisation mass spectrometry (TIMS) dating of zircons from volcanic tuffs in the Ditji Formation of the Bonaparte Basin and the Grant Group in the Canning Basin point to an Asselian age of about 295.25 Ma for this datum. All dated zircons from the Ditji Formation came from petroleum well cuttings but the accompanying palynology was mostly from sidewall cores; however, all Grant Group samples were from conventional core. TIMS dates from the Ditji Formation range in age from 295.2 to 292.7 Ma whereas the only productive tuff from the Grant Group yielded a 296.26 Ma date. By comparison, there are no zircon dates to constrain the onset of glacial deposition in Australia. The Bonaparte Basin ages overlap with those for the Edie Tuff (296.1-294.5 Ma) in Queensland's Galilee Basin, approximately 2000 km to the southeast, which also lies close to the base of the P. pseudoreticulata Zone. To date the only fossil group within the P. confluens Zone in Western Australia to provide independent age control, albeit loosely, are goniatites from the northern Perth Basin (Uraloceras irwinense and Juresanites jacksoni) that have consistently been attributed to the Sakmarian; these require a reassessment of their affinity with Russian faunas and therefore to global stratotypes. The position of the Carboniferous-Permian boundary is elusive in Australia and will remain so until additional volcanic tuffs containing young datable zircons are found; however, spore-pollen and zircon dates from Namibia place this boundary within the P. confluens Zone.
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BFBNIB, GIS, IJS, KISLJ, NUK, PNG, UL, UM, UPUK
Abstract Introduction Parkinson disease is noted for its association with mutations in GBA and the p.G2019S mutation in LRRK2 . This study aimed to evaluate the frequency of Ashkenazi founder ...mutations in sphingomyelin phosphodiesterase 1 ( SMPD1 ) in Ashkenazi patients diagnosed with Parkinson's disease (PD); and their impact on PD phenotypic expression. SMPD1 underlies the lysosomal storage disease - Niemann-Pick. Methods A case (n = 287) control (n = 400) study was undertaken. All patients underwent a physical, neurobehavioral and neurologic examination that incorporated the Unified Parkinson's Disease Rating Scale. Three founder SMPD1 Ashkenazi mutations (c.996delC (fsP330), p.L302P and p.R496L) were investigated in patients and controls, previously evaluated for carriage of founder mutations in GBA and the p.G2019S mutation in LRRK2. Results Nine (3.1%) PD patients compared to two (0.5%) individuals from the control group were found to carry one of the three Ashkenazi SMPD1 founder mutations (p = 0.007). The overall clinical characteristics of PD patients carrying SMPD1 mutations were similar to those of PD patients with no mutations in SMPD1 , GBA and LRRK2 (n = 189). Conclusion We maintain that disruptive mutations in SMPD1 constitute a risk factor for PD.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
The advent of chemical abrasion-isotope dilution thermal ionisation mass spectrometry (CA-IDTIMS) has revolutionised U-Pb dating of zircon, and the enhanced precision of eruption ages determined on ...volcanic layers within basin successions permits an improved calibration of biostratigraphic schemes to the numerical time-scale. The Guadalupian and Lopingian (Permian) successions in the Sydney, Gunnedah, Bowen and Canning basins are mostly non-marine and include numerous airfall tuff units, many of which contain zircon. The eastern Australian palynostratigraphic scheme provides the basis for much of the local correlation, but the present calibration of this scheme against the numerical time-scale depends on a correlation to Western Australia, using rare ammonoids and conodonts in that succession to link to the standard global marine biostratigraphic scheme. High-precision U-Pb zircon dating of tuff layers via CA-IDTIMS allows this tenuous correlation to be circumvented-the resulting direct calibration of the palynostratigraphy to the numerical time-scale highlights significant inaccuracies in the previous indirect correlation. The new data show: the top of the Praecolpatites sinuosus Zone (APP3.2) lies in the early Roadian, not the middle Kungurian; the top of the Microbaculispora villosa Zone (APP3.3) lies in the middle Roadian, not the early Roadian; the top of the Dulhuntyispora granulata Zone (APP4.1) lies in the Wordian, not in the latest Roadian; the top of the Didecitriletes ericianus Zone (APP4.2) lies in the first half of the Wuchiapingian, not the latest Wordian; the Dulhuntyispora dulhuntyi Zone (APP4.3) is exceptionally short and lies within the Wuchiapingian, not the early Capitanian; and the top of the Dulhuntyispora parvithola Zone (APP5) lies at or near the Permo-Triassic boundary, not in the latest Wuchiapingian.
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U-Pb dating and Hf-isotope provenance analysis of detrital zircons from the glaciogenic lower Permian Grant Group of the Canning Basin indicate sources principally from basement terranes in central ...Australia, with subordinate components from terranes to the south and north. Integrating these data with field outcrop and subsurface evidence for ice sheets, including glacial valleys and striated pavements along the southern and northern margins of the basin, suggests that continental ice sheets extended over several Precambrian upland areas of western and central Australia during the late Paleozoic ice age (LPIA). The youngest zircons constrain the maximum age for contemporaneous ice sheet development to the late Carboniferous (Kasimovian), whereas palynology provides a minimum age of early Permian (Asselian-Sakmarian). Considering the palynological age of the Grant Group within the context of regional and global climate proxies, the main phase of continental ice sheet growth was possibly in the Ghzelian-Asselian. The presence of ice sheets older than Kasimovian in western and central Australia remains difficult to prove given a regional gap in deposition possibly covering the mid-Bashkirian to early Ghzelian within the main depocentres and even larger along basin margins, and the poor evidence for older Carboniferous glacial facies. There is also no evidence for extensive glacial facies younger than mid-Sakmarian in this region as opposed to eastern Australia where the youngest regional glacial phase was Guadalupian.
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U-Pb dating of zircons from thin middle Permian tuffs in the Canning Basin of Western Australia by chemical abrasion-isotope dilution thermal ionisation mass spectrometry reveals a conflict with the ...established spore-pollen zonation. Normally, the first appearance datum of Dulhuntyispora granulata across the continent lies stratigraphically above assemblages assigned to the Microbaculispora villosa Zone. However, the youngest tuffs within non-marine facies from the M. villosa Zone in Pittston SD-1, drilled in the southwest of the Canning Basin, yielded an age of 267.04 ± 0.14 Ma, which is 1.7 million years younger than tuffs associated with the D. granulata Zone in marginal-marine facies from core holes 350-400 km to the northeast. The apparent conflict in ages is possibly due to the non-marine depositional environment having wielded a strong local influence on the palynoflora along the edge of this basin. Although the present information indicates an age 2.5 million years younger than the 266.6 Ma age previously suggested for the top of the M. villosa Zone, revisions to the ages of Roadian-Wordian spore-pollen zones are not considered justifiable without further supporting evidence. Furthermore, considerable care is needed when comparing palynological assemblages from significantly differing facies. Two basaltic sills (43.5 m and 20 m thick) immediately below the tuffaceous beds in Pittston SD-1 are coincidental, as Ar-Ar dating indicates a Late Triassic age for the intrusions.
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Detrital zircon U-Pb ages and heavy mineral assemblages provide conflicting evidence of the provenance of the Ordovician-lower Silurian Tumblagooda Sandstone, a fluvial to shallow marine, red-bed ...succession over 2000 m thick, within the northern Perth and Southern Carnarvon basins in Western Australia. Tourmaline composition indicates a main provenance from interior continental terranes dominated by 'Li-poor granitoids, pegmatites and aplites' and 'Ca-poor metapelites, metapsammites and quartz-tourmaline rocks,' akin to the Yilgarn Craton to the east of outcrop of the Tumblagooda Sandstone. Other possible source areas include orogens mostly to the south but lack tourmaline analyses for comparison. Taking into account the lack of garnets-a conspicuous component of the adjacent Proterozoic Northampton Inlier-the limited zircon data are compatible with the Albany-Fraser and Pinjarra orogens along the southern and western margins of Australia and/or terranes in or adjacent to East Africa and/or Antarctica, as ultimate source regions with a minor contribution from the Yilgarn Craton, as with other Phanerozoic strata in Western Australia. Whereas the textural and mineralogical maturity of the sandstone could be explained by derivation from such regions, it is more likely that the source was relatively local and that the sediment passed through several phases of reworking. The main source of ilmenite and hematite, by comparison, may have been mafic-ultramafic rocks and/or banded iron formations within the Archean Yilgarn Craton to the east or the Pilbara Craton to the northeast, mobilised by acidic meteoric waters. Iron oxides forming the earliest cements may have been derived from the oxidation of detrital hematite and ilmenite grains concentrated along some bedding laminae or transported in solution from beyond the zone of deposition. Whereas the detrital iron oxides most likely come from the craton to the east of outcrop of the Tumblagooda Sandstone, the sand grains appear to have originally come from a relatively local orogenic source.
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In view of the fact that cancer patterns in patients with Parkinson disease (PD) differ from the general population, we aimed to verify whether patients with PD with LRRK2 mutations have an increased ...risk for particular cancer types.
In this cross-sectional study, eligible consenting Jewish patients with PD were genotyped for the predominant LRRK2 G2019S mutation. Oncologic data were obtained by personal interview and reviewing patients' files. Stepwise logistic regression was applied to model the probability of cancer occurrence in carriers vs noncarriers.
Overall, 79/490 (16.1%) genotyped patients carried the G2019S mutation. Seventy-seven (16%) were diagnosed with cancer; of those, 67 (14%) with a non-skin cancer. Eighteen (23%) carriers vs 49 (12%) noncarriers had a non-skin cancer (p = 0.01, odds ratio OR = 2.18, 95% confidence interval CI 1.19-3.99). A significant ethnicity effect was noted (p = 0.045, OR = 1.84, 95% CI 1.02-3.34). Among Ashkenazi patients, age and LRRK2 emerged as significant using stepwise logistic regression including age, gender, and LRRK2 status as explanatory variables. The OR for LRRK2 mutation carriers adjusted for age was 3.38 (95% CI 1.64-6.97, p = 0.0009).
Ashkenazi Jewish patients with PD who harbor the G2019S LRRK2 mutation are more likely to have a concomitant non-skin cancer than noncarriers.
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