The Middle Jurassic (Bathonian)-Upper Cretaceous (Maastrichtian) deposits exposed at the southern front of the Central High Atlas (CHA, Southern Morocco) include thick fluvial successions largely ...undifferentiated in previous studies. These continental strata record a long period of relief formation due to crustal shortening and subsequent denudation that predated the Cenozoic, syn-collisional, tectonic inversion of the CHA. This study, carried out through mapping along more than 270 km between Ouarzazate and Errachidia towns, firstly proposes a rock-stratigraphic unified scheme based on a framework of unconformity-bounded stratigraphic units, including sub-units, differentiated for their specific depositional meaning. Secondly, the geological maps and related cross-sections illustrate the evidence of syn-depositional shortening with distinct deformation styles, outlining pre- and syn-collisional tectonic inversion.
As-bearing travertine rocks from Tuscany (Italy), where previous studies suggested the existence of a CO
3
2−
⇔
AsO
3
3− substitution in the calcite lattice, were investigated with X-ray Absorption ...Spectroscopy (XAS) at the As K-edge (11,867
eV). In two of the studied samples, XANES indicates that As is in the 5+ oxidation state only, and EXAFS analysis reveals a local environment typical of arsenate species. For these samples, the lack of detectable second shell signals suggests a poorly ordered environment, possibly corresponding to an adsorption onto oxide and/or silicate phases. On the other hand, in the third sample XANES reveals a mixed As oxidation state (III and V). This sample also presents evident next nearest neighbor coordination shells, attributed to As–Ca and As–As contributions. The occurrence of next neighbor shells is evidence that part of As is incorporated in an ordered lattice. Furthermore, the local structure revealed by EXAFS is compatible with As incorporation in the calcite phase, as further supported by DFT simulations. The observation of next neighbors shells only in the As(III)-rich sample suggests the substitution of the arsenite group in place of the carbonate one (CO
3
2−
⇔
AsO
3
3−). The conclusion of this work is that uptake of As by calcite is in general less favored than adsorption onto iron oxhydroxides, but could become environmentally important wherever the latter phenomenon is hindered.
The valley of the Pecora river (southern Tuscany, Italy) hosts a very large (∼
25
km
2) arsenic anomaly, with rock values up to ∼
1000
mg/kg. Its origin (natural or anthropogenic) is still debated. A ...systematic study of a well developed Neogene–Quaternary sequence in the middle Pecora valley (MPV) reveals that each formation of the sequence has a distinctive, definite range of arsenic contents. Specifically, all but one Upper Messinian sands and gravels (M2 formation) show 4–39
mg/kg As (mean 20, SD 12); the overlying Quaternary alluvial deposits (P1) have the highest contents (142–1157
mg/kg, mean 647, SD 288); and the topmost calcareous tufa (P2) show intermediate contents (83–243
mg/kg, mean 159, SD 50, except for a single, silica-rich sample having 420
mg/kg). This distribution cannot be explained by any anthropogenic practice, and points to a geogenic origin of the anomaly. We suggest that the arsenic anomaly of MPV is basically the result of erosion and fluvial transport processes of country rocks hosting vein mineral deposits. This hypothesis is fully consistent with a recent reconstruction of the paleogeographic evolution of the Pecora river catchment. Moreover, a recent study pointed out a similar anomaly in the neighboring Val di Cornia; thus the MPV anomaly could be just a part of a larger system. An implication of this study is that mobilization of arsenic in shallow systems may be related to gravitational transport of clastic sediments, causing a memory effect that may be preserved for relatively long times. This process of mobilization may involve very large rock volumes, resulting in regional scale anomaly.
This article reports a stratigraphic and structural analysis of the Neogene‐Quaternary Valdelsa Basin (Central Italy), filled with up to 1000 m of uppermost Miocene to lower Pleistocene strata. The ...succession is subdivided into seven unconformity‐bounded stratigraphic units (synthems, or large‐scale depositional sequences) that include fluvio‐deltaic and shallow‐marine deposits. Structures related to basin shoulders and internal boundaries controlled the Neogene location and geometry of different depocentres. During the Tortonian‐Messinian, a buried NE‐trending high related to regional, basin‐transverse lineaments separated two adjacent sub‐basins. During the lower Pliocene, compressional displacement along NW‐trending, thrust‐related highs controlled the distribution of depocentres and dispersal of sediment. Extensional tectonics, although previously considered the dominant deformation style affecting the rear of the Northern Apennines since the late Miocene, is no longer considered a dominant control on tectono‐sedimentary development of the Valdelsa basin. Instead, the Valdelsa Basin shares features with continental hinterland basins of orogenic belts where compression, extension, and transcurrent stress fields determine a complex spatial and temporal record of accommodation and sediment supply. In the Valdelsa Basin tectonics and eustatic sea‐level fluctuations were dominant in forcing the deposition of sedimentary cycles at several scales. Zanclean and Gelasian large‐scale depositional sequences were mainly controlled by crustal shortening, whereas a eustatic signal was preferentially recorded during the Piacenzian. Smaller scale depositional sequences, common to most synthems, were controlled by orbitally forced glacio‐eustatic cycles.
The European Society of Cardiology (ESC) guidelines (GL) provide indications on the mode of delivery in women with heart disease. However available data suggests that the rate of Cesarean Delivery ...(CD) is high and widely variable among such patients. In this study, we aimed to investigate the degree of adherence to the ESC recommendations among women delivering in four tertiary maternity services in Italy and how this affects the maternal and neonatal outcomes.
Retrospective multicenter cohort study including pregnant women with heart disease who gave birth between January 2014 and July 2020. Composite adverse maternal outcome (CAM) was defined by the occurrence of one or more of the following: major postpartum hemorrhage, thrombo-embolic or ischemic event, de novo arrhythmia, heart failure, endocarditis, aortic dissection, need for re-surgery, sepsis, maternal death. Composite Adverse Neonatal outcome (CAN) was defined as cord arterial pH <7.00, APGAR <7 at 5 min, admission to the intensive care unit, and neonatal death. We compared the incidence of CAM and CAN between the cases with planned delivery in accordance (group "ESC consistent") or in disagreement (group "ESC not consistent") with the ESC GL.
Overall, 175 women and 181 liveborn were included. A higher frequency of CAN was found when delivery was not planned accordingly to the ESC guidelines ("ESC consistent" 9/124 (7.2%) vs "ESC not consistent" 13/57 (22.8%) p = 0.002 OR 3.74 (CI 95% 1.49-9.74) , while the occurrence of CAM was comparable between the two groups. At logistic regression analysis, the gestational age at delivery was the only parameter independently associated with the occurrence of CAN (p = 0.006).
Among pregnant women with heart disease, deviating from the ESC guidelines scheduling cesarean delivery does not seem to improve maternal outcomes and it is associated with worse perinatal outcomes, mainly due to lower gestational age at birth.
The study of a huge repertory of sparse glazed ware from Donoratico (Livorno, Italy) dated back to the ninth century was carried out to investigate the production technology via petrographic, ...chemical, and isotopic investigations. The mineralogical and chemical evidence suggested the application of a lead oxide flux to an unfired non‐calcareous ceramic body, in accordance with late Antique and early‐Medieval traditions. The isotopic investigation of the glazes also suggested different sources for PbO, which was frequently applied as a mix of different metal batches. The Pb isotopic record identified the Southern Tuscany districts (Campiglia Marittima and Colline Metallifere) and a source controlled by the Carolingian kings in the northern districts of Central Europe (either in Aquitaine or in the Middle German ore districts) as the most reliable sources. SEM‐EDS showed the presence of tin impurities in the form of secondary cassiterite agglomerates in most of the glazes obtained by the use of local lead. The presence of cassiterite veins in Southern Tuscany lead sulphide deposits was considered as the main cause for tin impurities in the glazing mixture and, thus, an important marker for the exploitation of local lead.
Purpose
We sought to conduct the largest retrospective study to date of open tibia fractures and describe the incidence of complications and evaluate the potential predictive risk factors for ...complications.
Methods
Patients with open tibia fractures treated with reamed intramedullary nail (IMN) across a 10-year period were evaluated. Patient charts were reviewed for demographics, type of open fracture (T), comorbidities, and postoperative complications. A multivariate model was conducted to determine the risk factors for each type of complication.
Results
Of the 486 patients with open tibia fractures, 13 % (
n
= 64) had infections, 12 % (
n
= 56) had nonunions, and 1 % (
n
= 7) had amputations. TIII fractures had much higher rates of each complication than TI and TII fractures. Fracture type was the only significant risk factor for both nonunion and infection.
Conclusion
Our study found that the Gustilo grade of open tibia fracture is by far the greatest predictor of nonunion and infection.
This study is based upon a stratigraphic and structural revision of a Middle Jurassic–Upper Cretaceous mostly continental succession exposed between Boumalne Dades and Tinghir (Southern Morocco), and ...aims at reconstructing the relation among sedimentary, tectonic and magmatic processes that affected a portion of the Central High Atlas domains. Basalts interbedded in the continental deposits have been sampled in the two studied sites for petrographic, geochemical and radiogenic isotope analyses. The results of this study provide: (1) a robust support to the local stratigraphic revision and to a regional lithostratigraphic correlation based on new
40
Ar–
39
Ar ages (ca. 120 Ma) of the intervening basalts; (2) clues for reconstructing the relation between magma emplacement in a structural setting characterized by syn-depositional crustal shortening pre-dating the convergent tectonic inversion of the Atlasic rifted basins; (3) a new and intriguing scenario indicating that the Middle Jurassic–Lower Cretaceous basalts of the Central High Atlas could represent the first signal of the present-day Canary Islands mantle plume impinging, flattening, and delaminating the base of the Moroccan continental lithosphere since the Jurassic, and successively dragged passively by the Africa plate motion to NE. The tectono-sedimentary and magmatic events discussed in this paper are preliminarily extended from their local scale into a peculiar geodynamic setting of a continental plate margin flanked by the opening and spreading Central Atlantic and NW Tethys oceans. It is suggested that during the late Mesozoic this setting created an unprecedented condition of intraplate stress for concurrent crustal shortening, related mountain uplift, and thinning of continental lithosphere.
The present paper deals with compositional and microstructural features of 26 pre‐Islamic, South Arabian coins recently unearthed during archaeological excavations. Most of the investigated coins ...come from Sumhuram (Khor Rori, southern Oman), and were minted by the Hadramawt kingdom (fourth century bc to third century ad); only a few of them belong to the Himyarite kingdom's coinage (first to fourth centuries ad). In addition, some coins of both the Hadramawt and the Himyarite kingdoms found at Qani' (B'ir ‘Ali, Republic of Yemen) have been analysed for comparison. Our main focus was to provide new hints towards the comprehension of the chronological evolution in South Arabian coinage in terms of both metal composition and minting techniques. In addition, some melting crucibles found at Sumhuram have been examined in an attempt to make a comparison with the coins’ composition and to test the hypothesis that they were used for minting operations.
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