scholarly journals The Bigrlyi Tabular Sandstone-Hosted Uranium–Vanadium Deposit, Ngalia Basin, Central Australia

Minerals ◽  
2020 ◽  
Vol 10 (10) ◽  
pp. 896
Author(s):  
Susanne Schmid ◽  
Wayne R. Taylor ◽  
Daniel P. Jordan
Keyword(s):  
Lead Isotope ◽  
Lower Grade ◽  
Red Sandstone ◽  
History Of ◽  
Mineralization Processes ◽  
Mineralized Zone ◽  
Central Australia ◽  
Feldspathic Sandstone ◽  
Over Time

The Bigrlyi deposit is a tabular, sandstone-hosted, uranium–vanadium deposit of Carboniferous age located in the Ngalia Basin of central Australia. The deposit is similar to the continental, fluvial Saltwash-type of sandstone-hosted U-V deposits which are well known from the Colorado Plateau, USA. Most mineralization at Bigrlyi occurs as thin, multiple-stacked, stratiform lenses at the base of fluvial channels near the contact between a grey sandstone succession and a hematitic, purple–red sandstone succession. A larger halo of lower grade vanadium mineralization extends beyond the main U-V-mineralized zone. The host is an immature, feldspathic sandstone, grading into arkose and lithic-rich variants. Lithic ‘rip-up’ clasts of clay-rich sediments are common in the basal parts of fluvial channels, and are frequently the focus of, and have acted as sites for, U-V mineralization. Coffinite and uraninite are the main uranium minerals, with the former dominant. Vanadium is mainly hosted by Fe-V-bearing clays and chlorite, including roscoelite, grading into vanadian illite, the interlayer mineral corrensite, and altered detrital biotite. The V-Fe–oxyhydroxide minerals montroseite, haggite and doloresite, and altered detrital Fe-Ti oxides, are minor V-hosts. Mineralized zones correlate with enrichments in Se, Li, Ba, Be, Mo, Mg and Fe, and elevated Se/S ratios are characteristic of U-mineralized zones. Petrographic studies show that a heterogeneous mixture of variably mineralized lithic clasts is present; in the same rock, some clasts are Fe-rich and only weakly U-V-mineralized, while other clasts are strongly V- and/or U-mineralized. These observations point to mineralization processes that did not take place in-situ in the host sandstone at the site of deposition as required by conventional groundwater models. Lead isotope results provide evidence of the open-system mobility of radiogenic elements in parts of the deposit. In V-bearing zones, radiogenic Pb contents were found to be unsupported by current U levels, suggesting that over time U has been mobilized from these zones and redistributed, resulting in U-enrichment in other parts of the deposit. Mobility pathways were likely open over time from early in the history of the Bigrlyi deposit. A hybrid mineralization model, involving an interplay between solution-precipitation processes, detrital transport and post-depositional U remobilization, is proposed for Bigrlyi. Ferrous-ion-bearing clay minerals and pyrite are considered to be the most likely primary reductants/adsorbents, while the deposit is lacking carbonaceous matter.

The Path of Standard Albanian Language Formation

2018 ◽  
Vol 5 (2) ◽  
pp. 106-115
Author(s):  
Sindorela Doli Kryeziu
Keyword(s):  
Single Unit ◽  
Cultural Factors ◽  
Language History ◽  
Whole Process ◽  
History Of ◽  
Social And Cultural Factors ◽  
Cultural Body ◽  
Over Time ◽  
Language Literature

Abstract In our paper we will talk about the whole process of standardization of the Albanian language, where it has gone through a long historical route, for almost a century.When talking about standard Albanian language history and according to Albanian language literature, it is often thought that the Albanian language was standardized in the Albanian Language Orthography Congress, held in Tirana in 1972, or after the publication of the Orthographic Rules (which was a project at that time) of 1967 and the decisions of the Linguistic Conference, a conference of great importance that took place in Pristina, in 1968. All of these have influenced chronologically during a very difficult historical journey, until the standardization of the Albanian language.Considering a slightly wider and more complex view than what is often presented in Albanian language literature, we will try to describe the path (history) of the standard Albanian formation under the influence of many historical, political, social and cultural factors that are known in the history of the Albanian people. These factors have contributed to the formation of a common state, which would have, over time, a common standard language.It is fair to think that "all activity in the development of writing and the Albanian language, in the field of standardization and linguistic planning, should be seen as a single unit of Albanian culture, of course with frequent manifestations of specific polycentric organization, either because of divisions within the cultural body itself, or because of the external imposition"(Rexhep Ismajli," In Language and for Language ", Dukagjini, Peja, 1998, pp. 15-18.)

Transocean and the History of Tax Inversions

2018 ◽  
Vol 34 (1) ◽  
pp. 1-12
Author(s):  
Susan M. Albring ◽  
Randal J. Elder ◽  
Mitchell A. Franklin
Keyword(s):  
Multinational Corporations ◽  
Economic Impacts ◽  
Income Taxes ◽  
Tax Rates ◽  
Corporate Tax ◽  
Corporate Income Taxes ◽  
History Of ◽  
Jobs Act ◽  
The U.S ◽  
Over Time

ABSTRACT The first tax inversion in 1983 was followed by small waves of subsequent inversion activity, including two inversions completed by Transocean. Significant media and political attention focused on transactions made by U.S. multinational corporations that were primarily designed to reduce U.S. corporate income taxes. As a result, the U.S. government took several actions to limit inversion activity. The Tax Cuts and Jobs Act of 2017 (TCJA) significantly lowered U.S. corporate tax rates and one expected impact of TCJA is a reduction of inversion activity. Students use the Transocean inversions to understand the reasons why companies complete a tax inversion and how the U.S. tax code affects inversion activity. Students also learn about the structure of inversion transactions and how they have changed over time as the U.S. government attempted to limit them. Students also assess the tax and economic impacts of inversion transactions to evaluate tax policy.

Historical Representations and Recent Changes

2018 ◽  
Author(s):  
Jürgen Schaflechner
Keyword(s):  
Comparative Analysis ◽  
South Asia ◽  
Oral Histories ◽  
Detailed History ◽  
Modern Times ◽  
History Of ◽  
Historical Representations ◽  
The Rich ◽  
Many Sources ◽  
Over Time

Chapter 3 introduces the tradition of ritual journeys and sacred geographies in South Asia, then hones in on a detailed history of the grueling and elaborate pilgrimage attached to the shrine of Hinglaj. Before the construction of the Makran Coastal Highway the journey to the Goddess’s remote abode in the desert of Balochistan frequently presented a lethally dangerous undertaking for her devotees, the hardships of which have been described by many sources in Bengali, Gujarati, Hindi, Sindhi, and Urdu. This chapter draws heavily from original sources, including travelogues and novels, which are supplanted with local oral histories in order to weave a historical tapestry that displays the rich array of practices and beliefs surrounding the pilgrimage and how they have changed over time. The comparative analysis demonstrates how certain motifs, such as austerity (Skt. tapasyā), remain important themes within the whole Hinglaj genre even in modern times while others have been lost in the contemporary era.

Introduction

2018 ◽  
Author(s):  
Marko Geslani
Keyword(s):  
Comparative Study ◽  
Royal Power ◽  
History Of ◽  
Historical Developments ◽  
The Comparative Study ◽  
The Relationship ◽  
Over Time ◽  
Indian Religion

The introduction reviews the historiographic problem of the relation between fire sacrifice (yajña) and image worship (pūjā), which have traditionally been seen as opposing ritual structures serving to undergird the distinction of “Vedic” and “Hindu.” Against such an icono- and theocentric approach, it proposes a history of the priesthood in relation to royal power, centering on the relationship between the royal chaplain (purohita) and astrologer (sāṃvatsara) as a crucial, unexplored development in early Indian religion. In order to capture these historical developments, it outlines a method for the comparative study of ritual forms over time.

The Growth of Historical Method in Tang China

2018 ◽  
Author(s):  
Charles Hartman ◽  
Anthony DeBlasi
Keyword(s):  
Eleventh Century ◽  
Seventh Century ◽  
Daily Production ◽  
Successor State ◽  
Historical Method ◽  
Official History ◽  
History Of ◽  
Over Time

This chapter discusses how the full emergence of the centralized, aristocratic state in the seventh century brought about an official historiography that was part of the bureaucracy of that state. Beginning in the Tang, each dynastic court maintained an office of historiography. Over time, a regularized process evolved that, in theory and often in reality, turned the daily production of court bureaucratic documents into an official history of the dynasty. Although this process was ongoing throughout the dynasty, the final, standard ‘dynastic history’ was usually completed after the dynasty's demise by its successor state. Indeed, the very concept of a series of dynastic histories that, taken together, would present an official history of successive, legitimate Chinese states, dates from the eleventh century.

scholarly journals North polar trough formation due to in-situ erosion as a source of young ice in mid-latitudinal mantles on Mars

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
J. Alexis P. Rodriguez ◽  
Kenneth L. Tanaka ◽  
Ali M. Bramson ◽  
Gregory J. Leonard ◽  
Victor R. Baker ◽  
...  
Keyword(s):  
Katabatic Wind ◽  
Spiral Pattern ◽  
Near Surface ◽  
Valuable Source ◽  
History Of ◽  
North Polar ◽  
Human Exploration ◽  
Erosional Event

AbstractThe clockwise spiral of troughs marking the Martian north polar plateau forms one of the planet’s youngest megastructures. One popular hypothesis posits that the spiral pattern resulted as troughs underwent poleward migration. Here, we show that the troughs are extensively segmented into enclosed depressions (or cells). Many cell interiors display concentric layers that connect pole- and equator-facing slopes, demonstrating in-situ trough erosion. The segmentation patterns indicate a history of gradual trough growth transversely to katabatic wind directions, whereby increases in trough intersections generated their spiral arrangement. The erosional event recorded in the truncated strata and trough segmentation may have supplied up to ~25% of the volume of the mid-latitude icy mantles. Topographically subtle undulations transition into troughs and have distributions that mimic and extend the troughs’ spiraling pattern, indicating that they probably represent buried trough sections. The retention of the spiral pattern in surface and subsurface troughs is consistent with the megastructure’s stabilization before its partial burial. A previously suggested warm paleoclimatic spike indicates that the erosion could have occurred as recently as ~50 Ka. Hence, if the removed ice was redeposited to form the mid-latitude mantles, they could provide a valuable source of near-surface, clean ice for future human exploration.

scholarly journals TIME THROUGH TIME: ITS EVOLUTION THROUGH WESTERN PHILOSOPHY IN SEVEN IDEAS

Think ◽  
2021 ◽  
Vol 20 (58) ◽  
pp. 23-38
Author(s):  
Emily Thomas
Keyword(s):  
Western Philosophy ◽  
The World ◽  
History Of ◽  
Over Time

ABSTRACTWhat is time? Just like everything else in the world, our understanding of time has changed continually over time. This article tracks this question through the history of Western philosophy and looks at major answers from the likes of Aristotle, Kant, and McTaggart.

scholarly journals Development of a Field Deployable Firebrand Flux and Condition Measurement System

2020 ◽  
Author(s):  
Simone Zen ◽  
Jan C. Thomas ◽  
Eric V. Mueller ◽  
Bhisham Dhurandher ◽  
Michael Gallagher ◽  
...  
Keyword(s):  
Imaging Techniques ◽  
Time History ◽  
Infrared Camera ◽  
Thermal Conditions ◽  
Particle Characterization ◽  
Fire Dynamics ◽  
Rate Of Spread ◽  
New Instrument ◽  
History Of

AbstractA new instrument to quantify firebrand dynamics during fires with particular focus on those associated with the Wildland-Urban Interface (WUI) has been developed. During WUI fires, firebrands can ignite spot fires, which can rapidly increase the rate of spread (ROS) of the fire, provide a mechanism by which the fire can pass over firebreaks and are the leading cause of structure ignitions. Despite this key role in driving wildfire dynamics and hazards, difficulties in collecting firebrands in the field and preserving their physical condition (e.g. dimensions and temperature) have limited the development of knowledge of firebrand dynamics. In this work we present a new, field-deployable diagnostic tool, an emberometer, designed to provide measurement of firebrand fluxes and information on both the geometry and the thermal conditions of firebrands immediately before deposition by combining a visual and infrared camera. A series of laboratory experiments were conducted to calibrate and validate the developed imaging techniques. The emberometer was then deployed in the field to explore firebrand fluxes and particle conditions for a range of fire intensities in natural pine forest environments. In addition to firebrand particle characterization, field observations with the emberometer enabled detailed time history of deposition (i.e. firebrand flux) relative to concurrent in situ fire behaviour observations. We highlight that deposition was characterised by intense, short duration “showers” that can be reasonably associated to spikes in the average fire line intensity. The results presented illustrate the potential use of an emberometer in studying firebrand and spot fire dynamics.

scholarly journals In Situ exploration of the giant planets

2021 ◽  
Author(s):  
O. Mousis ◽  
D. H. Atkinson ◽  
R. Ambrosi ◽  
S. Atreya ◽  
D. Banfield ◽  
...  
Keyword(s):  
Solar System ◽  
Giant Planets ◽  
Atmospheric Composition ◽  
Formation History ◽  
History Of ◽  
Composition Structure ◽  
Galileo Probe ◽  
Probe Measurements

AbstractRemote sensing observations suffer significant limitations when used to study the bulk atmospheric composition of the giant planets of our Solar System. This impacts our knowledge of the formation of these planets and the physics of their atmospheres. A remarkable example of the superiority of in situ probe measurements was illustrated by the exploration of Jupiter, where key measurements such as the determination of the noble gases’ abundances and the precise measurement of the helium mixing ratio were only made available through in situ measurements by the Galileo probe. Here we describe the main scientific goals to be addressed by the future in situ exploration of Saturn, Uranus, and Neptune, placing the Galileo probe exploration of Jupiter in a broader context. An atmospheric entry probe targeting the 10-bar level would yield insight into two broad themes: i) the formation history of the giant planets and that of the Solar System, and ii) the processes at play in planetary atmospheres. The probe would descend under parachute to measure composition, structure, and dynamics, with data returned to Earth using a Carrier Relay Spacecraft as a relay station. An atmospheric probe could represent a significant ESA contribution to a future NASA New Frontiers or flagship mission to be launched toward Saturn, Uranus, and/or Neptune.

Anterior approach levator plication for congenital ptosis, absorpable versus non absorpable sutures

2021 ◽  
pp. 112067212110053
Author(s):  
Moustafa Salamah ◽  
Ashraf Mahrous Eid ◽  
Hani Albialy ◽  
Sherif Sharaf EL Deen
Keyword(s):  
Randomized Study ◽  
Early Postoperative Period ◽  
Polyglactin 910 ◽  
Exclusion Criteria ◽  
Congenital Ptosis ◽  
History Of ◽  
Group A ◽  
Group B ◽  
Over Time

Purpose: To compare the efficacy of two different suture types in levator plication for correction of congenital ptosis. Subjects and methods: Prospective comparative interventional randomized study involving 42 eyes of 42 patients aged more than 6 years with congenital ptosis and good levator action. The exclusion criteria were as follows: bilateral ptosis, history of previous surgery, fair or poor levator action, and associated other ocular diseases. Patients were randomized into group A, in which double-armed 5/0 polyester Ethibond were used, and group B, in which double-armed 5/0 Coated Vicryl® (polyglactin 910) suture material we used. Outcomes including eyelid height and stability of eyelid height over time were compared with follow-up data. The MRD was 4.05 ± 0.36 mm and 3.95 ± 0.34 after 1 week for both groups A and B, respectively. At the end of study follow up period (24 weeks), the MRD was 3.60 ± 0.42 mm in group A, and 2.52 ± 0.85 mm in group B. Conclusion: No difference in eyelid height between two groups in early postoperative period, but the postoperative eyelid height was more stable over time in the 5/0 polyester Ethibond group (group A) than in the 5/0 Coated Vicryl® (polyglactin 910) group (group B).

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