Orientation of tabular mafic intrusions controls convective vigour and crystallization style

The microstructure in basaltic dykes is significantly different to that in sills and lava lakes of the same bulk composition. For a given width of intrusion (or depth of lava lake), vertical tabular bodies are coarser-grained than horizontal bodies, with an invariant plagioclase shape across the intrusion. When comparing samples from sills and dykes for which the average grain size is the same, the dyke samples contain fewer small grains and fewer large grains than the sill samples. In contrast, the variation of median clinopyroxene-plagioclase-plagioclase dihedral angles in dykes correlates precisely with that observed in sills and is a function of the rate of diffusive heat loss. These patterns can be accounted for if the early stages of crystallization in dykes primarily involve the growth of isolated grains suspended in a well-mixed convecting magma, with the final stage (during which dihedral angles form) occurring in a crystal-rich static magma during which heat loss is primarily diffusive. In contrast, crystallization in sills occurs predominantly in marginal solidification fronts, suggesting that any convective motions are insufficient to entrain crystals from the marginal mushy layers and to keep them suspended while they grow. An exception to this general pattern is provided by members of the Mull Solitary Dykes, which propagated 100-1000 km SE from the Mull Palaeogene Igneous Centre, Scotland, through the shallow crust. These dykes, where sampled > 100 km from Mull, have a microstructure indistinguishable from that of a sill of comparable thickness. We suggest that sufficient nucleation and crystallization occurred in these dykes to increase the viscosity sufficiently to damp convection once unidirectional flow had ceased

Investigation into the effects of the geometry in cone driven midrange horns & phase plugs

Midrange horn loudspeakers are usually used in professional audio applications to improve efficiency and control directivity. Because traditional lumped parameter circuits do not model phase plugs or complexities of horn geometry after the expansion, the design of these horns is a complicated problem. In this project, Finite Element Analysis (FEA) Simulations were used to investigate the effects of the geometry of the phase plug and the compression cavity in front of the driver. It was found that the shape and size of the compression cavity has significant effect on the high frequency cut-off point of the system due to modal behaviour in the cavity. It was also found that if the horns expansion rate is maintained, the shape of the phase plug (and therefore horn wall) after the compression cavity can be used to control the directivity slightly, but only around the high frequency limit of the system

Exploring the properties of pyrogenic carbon with solid state ¹³C nuclear magnetic resonant spectroscopy: A combustion wind tunnel study

© Asia-Pacific Conference on Combustion, ASPACC 2019.All right reserved. Increasing the production of aryl carbon from wildland fire may be beneficial since it can be stored in soils for long periods of time rather than being emitted to the atmosphere or stored in soils in a less recalcitrant form. In this study, solid state 13C nuclear magnetic resonant spectroscopy is used to explore the properties of pyrogenic carbon produced by fires burning with different fire spread modes. Forest litter fuels were burnt using in a combustion wind tunnel using a replicated experimental design. Experiments were performed with three different fire spread modes, involving heading fires that spread with the wind, backing fires that spread against the wind and flanking fires that spread perpendicular to the wind. Results show that heading fires produce significantly more aryl carbon than flanking fires. Analysis of the results with principal component analysis show that maximising the residence time of high temperature combustion and the combustion factor could be an effective method for increasing the production of aryl carbon from fire

STATUS AND RECOMMENDATIONS FOR IN SITU ANOA (Bubalus sp.) WITH SUGGESTED IMPLICATIONS FOR THE CONSERVATION BREEDING POPULATION (Status dan Rekomendasi Anoa (Bubalus sp.) In Situ dengan Implikasi untuk Konservasi Populasi Berbiak)

Ringkasan ini menguraikan status konservasi in situ kerbau kerdil Sulawesi. Trend populasi yang dilaporkan dalam dua belas tahun terakhir mengarahkan penulis dalam menyoroti arti penting konservasi populasi berbiak di lokasi ex situ pada masa mendatang. Anoa terdiri dari dua jenis kerbau kerdil Bubalus depressicornis & B. quarlesi endemik Pulau Sulawesi, Indonesia. Kajian distribusi anoa berdasarkan laporan historis dan sebagai hasil data lapang terbaru (1990-an sampai 2002) menyoroti terjadinya penurunan di keseluruhan pulau, terutama di semenanjung selatan dan timur laut. Penurunan terjadi akibat perburuan lokal untuk daging dan kehilangan habitat. Sebagian besar populasi secara cepat mengalami fragmentasi. Konservasi populasi viable pada akhirnya akan membutuhkan pengelolaan metapopulasi dan peran yang lebih besar dari populasi di kebun binatang.Kata Kunci: in situ, anoa, konservasi, populasi berbiak

Outcome of patients with advanced ovarian cancer who do not undergo debulking surgery: A single institution retrospective review

OBJECTIVE: To assess the outcome of patients with advanced ovarian cancer (OC) who were treated without surgery, having received upfront chemotherapy and no interval debulking surgery (IDS). METHODS: Retrospective analysis of medical and chemotherapy records of consecutive patients with OC between 2005 and 2013 at UCL Hospitals London, UK who received neoadjuvant chemotherapy (NACT) was then found to be unsuitable for IDS following review by the multidisciplinary team. RESULTS: Eighty-three patients (18%) out of 467 receiving NACT did not undergo IDS. Median age was 70years (range 33-88); out of these 83 patients, 43 (51.8%) presented with stage IV disease. Forty-three of these 83 patients received carboplatin and paclitaxel (CP) (51.8%) and 37 received carboplatin alone (C) (44.6%); 3 patients (3.6%) received other platinum-based combinations. Reasons for not proceeding to surgery were: poor response to chemotherapy after 3-4 cycles of NACT (61/83, 73.5%); comorbidities (12/83, 14.5%); patient decision (4/83, 4.8%). Six patients (7.2%) received 2 lines of chemotherapy. In a univariate analysis CP, age <70years, and absence of comorbidities were factors influencing OS. In a multivariate analysis only having received CP remained independently associated with OS (HR 0.49, 95% CI 0.29-0.84). CONCLUSIONS: Chemotherapy alone can provide reasonable disease control in patients unsuitable for IDS and CP should be used if possible

Orthogonal polynomials of discrete variable and Lie algebras of complex size matrices

We give a uniform interpretation of the classical continuous Chebyshev's and Hahn's orthogonal polynomials of discrete variable in terms of Feigin's Lie algebra gl(N), where N is any complex number. One can similarly interpret Chebyshev's and Hahn's q-polynomials and introduce orthogonal polynomials corresponding to Lie superlagebras. We also describe the real forms of gl(N), quasi-finite modules over gl(N), and conditions for unitarity of the quasi-finite modules. Analogs of tensors over gl(N) are also introduced.Comment: 25 pages, LaTe