11 research outputs found
Foraminifera and microfacies of the type-Priabonian
The Priabonian is generally recognized and accepted as a stage name for
the uppermost Eocene. The name is derived from the small village ofPriabona
in the North Italian province of Vicenza (fig. 1). Since the underlying and
overlying stages of the idealized chronostratigraphic scale are based on sections
in completely different sedimentation areas in northwest Europe which
are remote from each other and from Priabona, the correlation between the
type sections, especially at the Eocene-Oligocene boundary has been a subject
of much discussion.
The predominantly carbonate facies of the Priabonian deposits contain
abundant larger foraminifera, and were therefore of great interest to paleontologists
at the beginning of the 20th century. Unfortunately the groups
represented belong to poorly defined lineages without distinct or sufficiently
well-known evolutionary trends. In addition, the scarcity of planktonic organisms
means that the type Priabonian is not very promising as a basis for
establishing modern biostratigraphic correlations.
The primary object of this study is to provide an illustrated record of the
smaller foraminifera, both benthonic and planktonic. The widest possible
range of habitats was obtained by investigating the contents of three sections:
the Buco della Rana section, thought to lie close to the Late Eocene shallow
carbonate platform; the off-shore Bressana section; and the Priabona section,
paleogeographically situated in an intermediate position on the slope between
platform and off-shore area. An additional study has been carried out involving
microfacies analysis of the carbonates ~nd quantitative investigations of the
benthonic faunas from intercalated marls. The purpose of this study was to
obtain a better appreciation of the environments of the deposition and a
correct biostratigraphic correlation of the three sections.
The original intention was to give a thorough account of biometrical data
on the larger foraminifera, but this had to be restricted to a detailed study of
certain assemblages of the Discocydinidae
The etiology of uterine sarcomas: A pooled analysis of the epidemiology of endometrial cancer consortium
Background: Uterine sarcomas are characterised by early age at diagnosis, poor prognosis, and higher incidence among Black compared with White women, but their aetiology is poorly understood. Therefore, we performed a pooled analysis of data collected in the Epidemiology of Endometrial Cancer Consortium. We also examined risk factor associations for malignant mixed mullerian tumours (MMMTs) and endometrioid endometrial carcinomas (EECs) for comparison purposes. Methods: We pooled data on 229 uterine sarcomas, 244 MMMTs, 7623 EEC cases, and 28 829 controls. Odds ratios (ORs) and 95% confidence intervals (CIs) for risk factors associated with uterine sarcoma, MMMT, and EEC were estimated with polytomous logistic regression. We also examined associations between epidemiological factors and histological subtypes of uterine sarcoma. Results: Significant risk factors for uterine sarcoma included obesity (body mass index (BMI)≥30 vs BMI<25 kg m-2 (OR: 1.73, 95% CI: 1.22-2.46), P-trend=0.008) and history of diabetes (OR: 2.33, 95% CI: 1.41-3.83). Older age at menarche was inversely associated with uterine sarcoma risk (≥15 years vs <11 years (OR: 0.70, 95% CI: 0.34-1.44), P-trend: 0.04). BMI was significantly, but less strongly related to uterine sarcomas compared with EECs (OR: 3.03, 95% CI: 2.82-3.26) or MMMTs (OR: 2.25, 95% CI: 1.60-3.15, P-heterogeneity=0.01). Conclusion: In the largest aetiological study of uterine sarcomas, associations between menstrual, hormonal, and anthropometric risk factors and uterine sarcoma were similar to those identified for EEC. Further exploration of factors that might explain patterns of age-and race-specific incidence rates for uterine sarcoma are needed. © 2013 Cancer Research UK. All rights reserved
Pregnancy Outcomes and Risk of Endometrial Cancer: A Pooled Analysis of Individual Participant Data in the Epidemiology of Endometrial Cancer Consortium
A full-term pregnancy is associated with reduced endometrial cancer risk; however, whether the effect of additional pregnancies is independent of age at last pregnancy is unknown. The associations between other pregnancy-related factors and endometrial cancer risk are less clear. We pooled individual participant data from 11 cohort and 19 case-control studies participating in the Epidemiology of Endometrial Cancer Consortium (E2C2) including 16,986 women with endometrial cancer and 39,538 control women. We used one- and two-stage meta-analytic approaches to estimate pooled odds ratios (OR) for the association between exposures and endometrial cancer risk. Ever having a full-term pregnancy was associated with a 41% reduction in risk of endometrial cancer compared to never having a full-term pregnancy (OR=0.59, 95% confidence interval (CI) 0.56-0.63). The risk reduction appeared greatest for the first full-term pregnancy (OR=0.78, 95%CI 0.72-0.84), with a further ~15% reduction per pregnancy up to eight pregnancies (OR=0.20, 95%CI 0.14-0.28) that was independent of age at last full-term pregnancy. Incomplete pregnancy was also associated with decreased endometrial cancer risk (7-9% reduction per pregnancy). Twin births appeared to have the same effect as singleton pregnancies. Our pooled analysis shows that, while the magnitude of the risk reduction is greater for a full-term pregnancy than an incomplete pregnancy, each additional pregnancy is associated with further reduction in endometrial cancer risk, independent of age at last full-term pregnancy. These results suggest the very high progesterone level in the last trimester of pregnancy is not the sole explanation for the protective effect of pregnancy
Coralline algal facies and their palaeoenvironments in the Late Eocene of Northern Italy (Calcare di Nago, Trento)
The Calcare di Nago is a carbonate unit of Middle-
Late Eocene (Bartonian and Priabonian) age which is
well exposed at the north-eastern end of Lake Garda, on
the western margin of the Lessini Shelf (Southern Alps).
This unit is highly fossiliferous as far as the coralline red
algae and large foraminifera are concerned. Corals, bryozoans,
echinoderms, and molluscs are also present. The
present study deals with the relationships among the
coralline taxa, the coralline growth-forms, and their
facies development in the Priabonian part of the type section of the Calcare di Nago. The taxonomic investigation
led to the identification of 15 coralline red algal species
belonging to 7 non-geniculate and 2 geniculate genera. One
species of Peyssonneliacean (red alga) and one of Halimedacean
(green alga) were also recognized. The quantitative and
qualitative analyses based on coralline red algae and large
foraminifera enabled five facies to be distinguished: Algal
crust-branch rudstone, AlgallDiscocyclina packstone, Coralalgal
boundstone, Rhodolith mound wacke/packstone, and
Rhodolith pavement. According to the coralline assemblages,
coralline growth-forms, and large foraminiferal associations,
the five facies reflect solid and soft substrate
types. Some of these facies are dominated by in situ rhodoliths,
others by reworked algal debris. In the architecture of an
interpreted prograding carbonate ramp, shallow water facies
are dominated by members of the subfamily Mastophoroideae,
while deeper water facies are dominated by those of
the subfamily Melobesioideae and family Sporolithaceae.
There is a significant increase both in size and in constructional
voids of the rhodoliths with depth. A concomitant
decrease in algal species diversity with depth has been also
recognized. Large Discocyclina assemblages are localized
across the inner and mid ramp boundary. Pellatispira and
Biplanispira are present only in the uppermost mid-ramp.
Nummulites, Assilina, and Spiroclypeus are dominant together
with small orthophragminids both in the mid- and
uppermost outer ramp facies