Igneous Layering, Fractional Crystallization and Growth of Granitic Plutons: the Dolbel Batholith in SW Niger

This study reassesses the development of compositional layering during the growth of granitic plutons, with emphasis on fractional crystallization and its interaction with both injection and inflation-related deformation. The Dolbel batholith (SW Niger) consists of 14, kilometre-sized plutons emplaced by pulsed magma inputs. Each pluton has a coarse-grained core and a peripheral layered series. Rocks consist of albite (An≤11), K-feldspar (Or96-99, Ab1-4), quartz, edenite (XMg = 0·37-0·55), augite (XMg = 0·65-0·72) and accessories (apatite, titanite and Fe-Ti-oxides). Whole-rock compositions are metaluminous, sodic (K2O/Na2O = 0·49-0·62) and iron-rich [FeOtot/(FeOtot + MgO) = 0·65-0·82]. The layering is present as size-graded and modally graded, sub-vertical, rhythmic units. Each unit is composed of three layers, which are, towards the interior: edenite ± plagioclase (Ca/p), edenite + plagioclase + augite + quartz (Cq), and edenite + plagioclase + augite + quartz + K-feldspar (Ck). All phases except quartz show zoned microstructures consisting of external intercumulus overgrowths, a central section showing oscillatory zoning and, in the case of amphibole and titanite, complexly zoned cores. Ba and Sr contents of feldspars decrease towards the rims. Plagioclase crystal size distributions are similar in all units, suggesting that each unit experienced a similar thermal history. Edenite, characteristic of the basal Ca/p layer, is the earliest phase to crystallize. Microtextures and phase diagrams suggest that edenite cores may have been brought up with magma batches at the site of emplacement and mechanically segregated along the crystallized wall, whereas outer zones of the same crystals formed in situ. The subsequent Cq layers correspond to cotectic compositions in the Qz-Ab-Or phase diagram at PH2O = 5 kbar. Each rhythmic unit may therefore correspond to a magma batch and their repetition to crystallization of recurrent magma recharges. Microtextures and chemical variations in major phases allow four main crystallization stages to be distinguished: (1) open-system crystallization in a stirred magma during magma emplacement, involving dissolution and overgrowth (core of edenite and titanite crystals); (2) in situ fractional crystallization in boundary layers (Ca/p and Cq layers); (3) equilibrium ‘en masse' eutectic crystallization (Ck layers); (4) compaction and crystallization of the interstitial liquid in a highly crystallized mush (e.g. feldspar intercumulus overgrowths). It is concluded that the formation of the layered series in the Dolbel plutons corresponds principally to in situ differentiation of successive magma batches. The variable thickness of the Ck layers and the microtextures show that crystallization of a rhythmic unit stops and it is compacted when a new magma batch is injected into the chamber. Therefore, assembly of pulsed magma injections and fractional crystallization are independent, but complementary, processes during pluton constructio

Igneous Layering, Fractional Crystallization and Growth of Granitic Plutons: the Dolbel Batholith in SW Niger

This study reassesses the development of compositional layering during the growth of granitic plutons, with emphasis on fractional crystallization and its interaction with both injection and inflation-related deformation. The Dolbel batholith (SW Niger) consists of 14, kilometre-sized plutons emplaced by pulsed magma inputs. Each pluton has a coarse-grained core and a peripheral layered series. Rocks consist of albite (An≤11), K-feldspar (Or96-99, Ab1-4), quartz, edenite (XMg = 0·37-0·55), augite (XMg = 0·65-0·72) and accessories (apatite, titanite and Fe-Ti-oxides). Whole-rock compositions are metaluminous, sodic (K2O/Na2O = 0·49-0·62) and iron-rich [FeOtot/(FeOtot + MgO) = 0·65-0·82]. The layering is present as size-graded and modally graded, sub-vertical, rhythmic units. Each unit is composed of three layers, which are, towards the interior: edenite ± plagioclase (Ca/p), edenite + plagioclase + augite + quartz (Cq), and edenite + plagioclase + augite + quartz + K-feldspar (Ck). All phases except quartz show zoned microstructures consisting of external intercumulus overgrowths, a central section showing oscillatory zoning and, in the case of amphibole and titanite, complexly zoned cores. Ba and Sr contents of feldspars decrease towards the rims. Plagioclase crystal size distributions are similar in all units, suggesting that each unit experienced a similar thermal history. Edenite, characteristic of the basal Ca/p layer, is the earliest phase to crystallize. Microtextures and phase diagrams suggest that edenite cores may have been brought up with magma batches at the site of emplacement and mechanically segregated along the crystallized wall, whereas outer zones of the same crystals formed in situ. The subsequent Cq layers correspond to cotectic compositions in the Qz-Ab-Or phase diagram at PH2O = 5 kbar. Each rhythmic unit may therefore correspond to a magma batch and their repetition to crystallization of recurrent magma recharges. Microtextures and chemical variations in major phases allow four main crystallization stages to be distinguished: (1) open-system crystallization in a stirred magma during magma emplacement, involving dissolution and overgrowth (core of edenite and titanite crystals); (2) in situ fractional crystallization in boundary layers (Ca/p and Cq layers); (3) equilibrium ‘en masse' eutectic crystallization (Ck layers); (4) compaction and crystallization of the interstitial liquid in a highly crystallized mush (e.g. feldspar intercumulus overgrowths). It is concluded that the formation of the layered series in the Dolbel plutons corresponds principally to in situ differentiation of successive magma batches. The variable thickness of the Ck layers and the microtextures show that crystallization of a rhythmic unit stops and it is compacted when a new magma batch is injected into the chamber. Therefore, assembly of pulsed magma injections and fractional crystallization are independent, but complementary, processes during pluton constructio

Fabry in the older patient: Clinical consequences and possibilities for treatment.

Baseline demographic and phenotypic characteristics of patients aged ≥50years in the Fabry Outcome Survey (Shire; data extracted June 2014) were compared with younger adults to investigate potential factors influencing treatment decisions in later life. Age groups were defined using age at treatment initiation or at FOS entry for untreated patients: 18-49 (n=1344; 49.5% male; 64.6% received agalsidase alfa enzyme replacement therapy [ERT]); 50-64 (n=537; 35.4% male; 74.3% treated); 65-74 (n=137; 32.1% male; 68.6% treated); and ≥75years (n=26; 26.9% male; 50.0% treated). Successive age groups showed higher median age at first symptom and diagnosis. Median alpha-galactosidase A activity, measured as percentage activity of the midpoint of the normal range, was much greater in females than males of all groups except ≥75years (33.4% in females; 27.8% in males). Patients aged ≥75years showed greater values than patients aged 18-49years for median left ventricular mass indexed to height (62.7 vs 42.4g/m(2.7)), mean ventricular wall thickness (15.0 vs 10.0mm) and prevalence of hypertension (57.7% vs 21.8%), and lower median estimated glomerular filtration rate (Modification of Diet in Renal Disease: 65.6 vs 98.5mL/min/1.73m(2)). Larger proportions in the groups aged ≥50 exhibited cardiac and/or cerebrovascular manifestations compared with patients aged 18-49years. The smaller proportion of patients receiving ERT aged ≥75years compared with the younger groups might reflect relatively milder disease burden or physician/patient reluctance to initiate/continue ERT at this age. Further studies are needed to increase knowledge of Fabry disease and ERT in later life

Ascending aortic remodelling in Fabry disease after long-term enzyme replacement therapy.

Previous cross-sectional studies reported a high prevalence of ascending aorta dilations/aneurysms in male adults with Fabry disease, independently of cardiovascular risk factors. To characterise the remodelling of the ascending aorta in classic Fabry disease under long-term enzyme replacement therapy. Diameter of the ascending aorta was measured with magnetic resonance imaging at the sino-tubular junction (STJ), and proximal (pAsAo), and distal ascending aorta (dAsAo) at baseline, and after 5 and 10 years of enzyme replacement therapy in 15 adult Fabry patients (10 males; 5 females). Over a mean follow-up of 9.5 years, the annual expansion rates measured in 10 males with Fabry disease were 0.41 ± 0.16, 0.36 ± 0.25 and 0.41 ± 0.26 mm/y at the STJ, pAsAo and dAsAo, respectively. Expansion rate at the pAsAo level in male patients was significantly higher than the expected expansion projected from theoretical normal values: 0.36 ± 0.25 vs 0.13 ± 0.05, p = 0.017. In 5 females, the annual expansion rates at the STJ, pAsAo and dAsAo were 0.14 ± 0.11, 0.21 ± 0.18 and 0.26 ± 0.24 mm/y, respectively. There was no significant difference from the projected normal expansion rate at the level of the pAsAo: 0.21 ± 0.18 vs 0.13 ± 0.04, p = 0.39. Our data suggest that the remodelling of the ascending aorta is more pronounced in male patients with Fabry disease under long-term enzyme replacement therapy compared with the progression observed in a large population study

The DoF-Box project: An educational kit for configurable robots

China: Shanghai. AirportCNAC is the China National Aviation Corporation. The Shanghai Longhua Airport.GrayscaleForman Nitrate Negatives, Box 2

Morphology, dynamics and plasma parameters of plumes and inter-plume regions in solar coronal holes

Coronal plumes, which extend from solar coronal holes (CH) into the high corona and - possibly - into the solar wind (SW), can now continuously be studied with modern telescopes and spectrometers on spacecraft, in addition to investigations from the ground, in particular, during total eclipses. Despite the large amount of data available on these prominent features and related phenomena, many questions remained unanswered as to their generation and relative contributions to the high-speed streams emanating from CHs. An understanding of the processes of plume formation and evolution requires a better knowledge of the physical conditions at the base of CHs, in plumes and in the surrounding inter-plume regions (IPR). More specifically, information is needed on the magnetic field configuration, the electron densities and temperatures, effective ion temperatures, non-thermal motions, plume cross-sections relative to the size of a CH, the plasma bulk speeds, as well as any plume signatures in the SW. In spring 2007, the authors proposed a study on "Structure and dynamics of coronal plumes and inter-plume regions in solar coronal holes" to the International Space Science Institute (ISSI) in Bern to clarify some of these aspects by considering relevant observations and the extensive literature. This review summarizes the results and conclusions of the study. Stereoscopic observations allowed us to include three-dimensional reconstructions of plumes. Multi-instrument investigations carried out during several campaigns led to progress in some areas, such as plasma densities, temperatures, plume structure and the relation to other solar phenomena, but not all questions could be answered concerning the details of plume generation process(es) and interaction with the SW.Comment: To appear on: The Astronomy and Astrophysics Review. 72 pages, 30 figure