Kimberlite: Rapid Ascent of Lithospherically Modified Carbonatitic Melts

Author(s):  
J. K. Russell ◽  
L. A. Porritt ◽  
L. Hilchie
Keyword(s):  
Author(s):  
Corrado Manni ◽  
Sergio I. Magalini

The rescue of victims of accidents during underwater activities, and the treatment of the pathology provoked by too rapid ascent in diving, are unfortunately problems which still remain relevant today. The concept of rapid artificial recompression is at the basis of the fundamental therapeutic techniques for the early treatment of all those involved in accidents of this type. Though numerous advances have been achieved in this field, many practical limitations still prevent their complete utilization.


Science ◽  
2019 ◽  
Vol 364 (6439) ◽  
pp. eaav9713 ◽  
Author(s):  
Asik Hossain ◽  
Aditya Bhattacharyya ◽  
Oliver Reiser

Visible-light photoredox catalysis offers a distinct activation mode complementary to thermal transition metal catalyzed reactions. The vast majority of photoredox processes capitalizes on precious metal ruthenium(II) or iridium(III) complexes that serve as single-electron reductants or oxidants in their photoexcited states. As a low-cost alternative, organic dyes are also frequently used but in general suffer from lower photostability. Copper-based photocatalysts are rapidly emerging, offering not only economic and ecological advantages but also otherwise inaccessible inner-sphere mechanisms, which have been successfully applied to challenging transformations. Moreover, the combination of conventional photocatalysts with copper(I) or copper(II) salts has emerged as an efficient dual catalytic system for cross-coupling reactions.


2018 ◽  
Vol 5 (4) ◽  
pp. 1075
Author(s):  
Dharmendra Kumar ◽  
T. K. Rath ◽  
L. C. Verma

High altitude cerebral edema (HACE) and High altitude pulmonary edema (HAPO) are the most dreaded complications related to high altitude. Authors managed a case of HACE and HAPO simultaneously set at unusually low height (1200 ft) in a patient. The altitude was not too much to develop these comorbidities as studied earlier. Relationship with altitude was immaterial in our case. However, rapid ascent without proper acclimatisation, young and tender age, male sex and smoking were associated contributing factors. He was managed with standard protocol and descent to lower altitude.


2019 ◽  
Vol 7 (1) ◽  
pp. 81-91 ◽  
Author(s):  
Oscar W Fitch-Roy ◽  
David Benson ◽  
Bridget Woodman

The selection and design of renewable electricity support instruments is an important part of European Union (EU) energy policy and central to the governance of the Energy Union. In 2014, the European Commission published updated guidelines for state aid that effectively mandate the EU-wide implementation of auctions for allocating revenue support to commercial scale renewable electricity generation. This article argues that the RES auction’s rapid ascent towards dominance is explained by a coincidence of an activist interpretation of EU state aid law creating demand for knowledge about the instrument and the emergence of a ready source of supply from a burgeoning community of a RES auction specialists and experts. Knowledge gained through EU-wide implementation of auctions further adds to supply of auctions expertise among the community. The implications of positive feedback between instrument demand and the growing supply of knowledge about an instrument reinforces the importance of critical engagement between policymakers and policy experts.


2017 ◽  
Vol 23 (7) ◽  
pp. 537-538
Author(s):  
Charles R. Doarn ◽  
Ronald C. Merrell
Keyword(s):  

Author(s):  
Xiao-Han Gong ◽  
Ji-Feng Xu ◽  
Ren-Deng Shi ◽  
Ben-Xun Su ◽  
Qi-Shuai Huang ◽  
...  

Garnet-bearing peridotites commonly occur in the deeper parts of mature or thickened oceanic lithosphere, and are rarely exhumed and emplaced onto the seafloor. The Purang ophiolitic peridotites in south Tibet contain rare symplectite pseudomorphs after garnet, offering a unique window into the still poorly understood evolution of the deep oceanic lithosphere. Here, integrated petrologic and Os-Li isotopic data are used to constrain the evolution and dynamics of emplacement for these garnet peridotite protoliths. The Purang peridotites show wide variations of chemical compositions (spinel Cr#: 0.2−0.8) and Os model ages (up to 2.0 Ga), thus representing a piece of heterogeneous oceanic mantle lithosphere. Dunite channels show two distinctive groups of Cr# of spinels and Os-isotope compositions, with the low- to medium-Cr# (0.2−0.6) and high-Cr# (0.7−0.8) dunites reflecting the reaction of host lherzolites/harzburgites with percolating mid-ocean ridge basalt−like and boninitic melts, respectively. This confirms recent subduction initiation-related melt percolation in the Purang peridotites. Coexisting olivines and pyroxenes in the peridotites show systematic Li elemental and isotopic disequilibrium, suggesting fast cooling of the peridotites to Li closure temperature shortly after the melt percolations, likely during exhumation of the peridotites onto the seafloor. This supports a close link between subduction initiation and tectonic emplacement of the Purang peridotites. Combined with other geological evidence, we suggest the Purang peridotites may originate from the deep part of old, thick oceanic lithosphere of the Neo-Tethys. This thick oceanic lithosphere was progressively weakened and thinned likely during widespread plume-lithosphere interaction, triggering the transformation of garnet peridotite protoliths to spinel peridotites. Subsequently, initiation of a new subduction zone along the lithospheric weakness caused rapid ascent and emplacement of the Purang peridotites at a nascent forearc.


Author(s):  
Christopher Shannon

This chapter argues that the best early twentieth-century Catholic social thinkers engaged the broader culture but were never assimilated by it. Their sacramental imaginations and openness to supernatural intervention represented a sign of contradiction against the faith-free academic social science in rapid ascent at the time. This prophetic option was especially appealing to converts, anti-modernists, and ex-radicals, but in the 1930s and 1940s it slowly found favor among a cohort of young ethnic Catholics, particularly those exposed to the Catholic Worker movement. The chapter further argues that sporadic attempts by prophetic Catholics to influence secular culture undermined the movement's spiritual foundation.


2020 ◽  
Vol 21 (2) ◽  
pp. 176-183
Author(s):  
Kai Erik Swenson ◽  
Marc Moritz Berger ◽  
Mahdi Sareban ◽  
Franziska Macholz ◽  
Peter Schmidt ◽  
...  

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