Application of molybdenum and thallium isotopes as indicators of paleoredox conditions and genesis of hyper-enriched black shale deposits, Peel River, Yukon, Canada

ABSTRACT Hyper-enriched black shale (HEBS) deposits in northern Yukon, consist of thin (<10 cm), laterally extensive (tens of thousands of km2) stratiform sulfide mineralization layer(s) that are hyper-enriched in Ni, Mo, Zn, platinum group elements, Re, and Au. The genesis of HEBS deposits and the ambient paleoenvironment in which they formed are the subject of vigorous debate. Non-traditional stable isotopes, particularly molybdenum and thallium, are robust paleoredox indicators and we have employed these isotope systems in this study of Yukon HEBS. Systematic sampling and Mo and Tl isotopic analysis of a continuous 200 m stratigraphic section through the Yukon HEBS mineralization and footwall and hanging-wall strata at the Peel River north and south bank showings (spaced five km apart) give δ98Mo –1.24 to –0.53‰ and –8.1 to –5.2 ε-units for the mineralization and –0.70 to 0.60‰ and –6.5 to –2.0 ε-units for the unmineralized strata. These values preclude a hydrothermal origin and strongly suggest that redox processes were responsible for the Yukon HEBS mineralization. The isotopic compositions, together with rare earth element (REE) systematics (REE profile, Y positive anomalies, Ce negative anomalies, and Y/Ho values) and other bulk geochemical redox indicators (Mo, V, Re/Mo, Ni/Co, U/Th, and V/Cr) indicate that the Peel River HEBS mineralization formed because of metal scavenging from seawater in a quiescent, euxinic basinal paleoenvironment.

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Comparison of Minimally Invasive Inductively Coupled Plasma–Mass Spectrometry Approaches for Strontium Isotopic Analysis of Medieval Stained Glass with Elevated Rubidium and Rare-Earth Element Concentrations

ACS Omega ◽

10.1021/acsomega.1c01939 ◽

2021 ◽

Author(s):

Alicia Van Ham-Meert ◽

Eduardo Bolea-Fernandez ◽

Joke Belza ◽

Dan Bevan ◽

Klaus Peter Jochum ◽

...

Keyword(s):

Mass Spectrometry ◽

Rare Earth ◽

Minimally Invasive ◽

Rare Earth Element ◽

Inductively Coupled Plasma ◽

Earth Element ◽

Isotopic Analysis ◽

Stained Glass ◽

Inductively Coupled ◽

Plasma Mass Spectrometry

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Use of platelet-rich plasma in regenerative medicine: technical tools for correct quality control

BMJ Open Sport & Exercise Medicine ◽

10.1136/bmjsem-2018-000442 ◽

2018 ◽

Vol 4 (1) ◽

pp. e000442 ◽

Cited By ~ 6

Author(s):

Hajer Graiet ◽

Anna Lokchine ◽

Pauline Francois ◽

Melanie Velier ◽

Fanny Grimaud ◽

...

Keyword(s):

Quality Control ◽

Whole Blood ◽

Sports Medicine ◽

Platelet Rich Plasma ◽

Systematic Sampling ◽

Significant Difference ◽

Platelet Concentration ◽

Harvesting Method ◽

Clinical Interest ◽

The Subject

Background/aimsPlatelet-rich plasma (PRP) injections are used in sports medicine and have been the subject of increased clinical interest. However, there have been very few reports of the composition of initial whole blood and the final PRP product. The objective of this study was to provide technical tools to perform a correct characterisation of platelets, leucocytes and red blood cells (RBCs) from whole blood and PRP.MethodsBlood and PRP were obtained from 26 healthy volunteers and prepared according to the varying parameters encountered within PRP process preparation and quantification (harvesting method, anticoagulant used, sampling method, counting method). Concentrations were measured at t=0, t=1, t=6 and t=24 hours.ResultsSampling of blood in Eppendorf tubes significantly decreased platelet concentration over time, whereas sampling in Microvette EDTA-coated tube kept platelet concentration stable until 24 hours. A non-significant difference was observed in platelet counts in PRP with impedance (median (IQR): 521.8 G/L (505.3–524.7)) and fluorescence (591.5 G/L (581.5–595.8)) methods. Other studied parameters did not influence platelet concentrations in blood or PRP samples. Leucocytes and RBC counts were similar whatever the anticoagulant, sampling, harvesting and counting methods used for both blood and PRP samples.ConclusionsSystematic sampling of blood and PRP in EDTA-coated tubes for quality control is recommended. The use of a validated counter for PRP sample should also be taken into account.

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Popular Theatre and the Changing Perspective of the Eighties

New Theatre Quarterly ◽

10.1017/s0266464x00001810 ◽

1985 ◽

Vol 1 (4) ◽

pp. 390-399 ◽

Cited By ~ 2

Author(s):

John McGrath

Keyword(s):

Recent Work ◽

Full Range ◽

Popular Theatre ◽

Good Night ◽

Commercial Success ◽

Working Through ◽

Film Version ◽

Important Study ◽

The Subject ◽

North And South

John McGrath is one of those few writers who, having begun his career in a success-fully orthodox manner, came to prefer working through ‘alternative’ channels – notably, in his formation and continuing work with the two 7:84 Companies, England and Scotland, their names reflecting the persistent fact that 84 per cent of the nation's wealth is owned by seven per cent of the population. Thus, McGrath's early work as one of the creators of the vintage TV series Z Cars, and his major ‘commercial’ success with the film version of his play Events while Guarding the Bofors Gun, has been succeeded by numerous plays and productions less familiar to conventional audiences, but which have made an enormous and often stirring impact in touring venues (frequently of a less expected kind) both north and south of the border. The full range of his work is charted in the ‘NTQ Checklist’ which follows this interview, and its development through to the mid– 'seventies was discussed in the earlier interview with McGrath in TQ19. reprinted in New Theatre Voices of the Seventies, edited by Simon Trussler (Methuen, 1981). Here, Tony Mitchell talks with John McGrath about some of his more recent work, and discusses his views on the nature of popular theatre, as set out in his important study of the subject, A Good Night Out (Methuen, 1981).

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On Some Flint Implements Beneath Blown Sand in Northern France

Proceedings of the Prehistoric Society of East Anglia ◽

10.1017/s0958841800024753 ◽

1922 ◽

Vol 3 (4) ◽

pp. 587-596

Author(s):

R. H. Chandler

Keyword(s):

Sand Dunes ◽

Main Road ◽

The Road ◽

Northern France ◽

The Subject ◽

North And South

The implements forming the subject of this note were found at the base of the Blown Sand Dunes which extend along the coast of Pas de Calais and attain, in the neighbourhood of Etaples, a height of 60 metres.The principal sites are grouped about the outstanding pinacle of sand immediately opposite the Etaples Military Cemetery, and are on the east of the road to Boulogne and about one mile out of Etaples.This pinacle of sand is the highest dune seen from the road (it reaches up to about 50 metres) and it is in the dunes ranging north and south of this pinacle, where the wind has scooped out hollows in the western face, and reached down to the underlying chalk and gravel, that the implements and flakes occur so abundantly.Generally speaking there are low dunes bordering the Canche River, but on the east of the main road they rise in a fairly pronounced range to between 40 and 50 metres, then they fall away to about 25-30 metres and rise again, ¼ to ½ a mile further inland to about 60 metres.

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The Effect of Training and Testing Process on Machine Learning in Biomedical Datasets

Mathematical Problems in Engineering ◽

10.1155/2020/2836236 ◽

2020 ◽

Vol 2020 ◽

pp. 1-17 ◽

Cited By ~ 4

Author(s):

Muhammed Kürşad Uçar ◽

Majid Nour ◽

Hatem Sindi ◽

Kemal Polat

Keyword(s):

Machine Learning ◽

Sampling Methods ◽

Sampling Theorem ◽

Systematic Sampling ◽

Fourth Section ◽

Sampling Theorems ◽

Testing Stage ◽

The Subject ◽

Selection Algorithms

Training and testing process for the classification of biomedical datasets in machine learning is very important. The researcher should choose carefully the methods that should be used at every step. However, there are very few studies on method choices. The studies in the literature are generally theoretical. Besides, there is no useful model for how to select samples in the training and testing process. Therefore, there is a need for resources in machine learning that discuss the training and testing process in detail and offer new recommendations. This article provides a detailed analysis of the training and testing process in machine learning. The article has the following sections. The third section describes how to prepare the datasets. Four balanced datasets were used for the application. The fourth section describes the rate and how to select samples at the training and testing stage. The fundamental sampling theorem is the subject of statistics. It shows how to select samples. In this article, it has been proposed to use sampling methods in machine learning training and testing process. The fourth section covers the theoretic expression of four different sampling theorems. Besides, the results section has the results of the performance of sampling theorems. The fifth section describes the methods by which training and pretest features can be selected. In the study, three different classifiers control the performance. The results section describes how the results should be analyzed. Additionally, this article proposes performance evaluation methods to evaluate its results. This article examines the effect of the training and testing process on performance in machine learning in detail and proposes the use of sampling theorems for the training and testing process. According to the results, datasets, feature selection algorithms, classifiers, training, and test ratio are the criteria that directly affect performance. However, the methods of selecting samples at the training and testing stages are vital for the system to work correctly. In order to design a stable system, it is recommended that samples should be selected with a stratified systematic sampling theorem.

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3. A global art history?

Art History: A Very Short Introduction ◽

10.1093/actrade/9780198831808.003.0003 ◽

2020 ◽

pp. 48-62

Author(s):

Dana Arnold

Keyword(s):

South America ◽

Art History ◽

Artistic Practice ◽

Western Art ◽

The World ◽

The Subject ◽

The Yuan Dynasty ◽

North And South America ◽

Global Art ◽

North And South

Are the practices of Western art history appropriate for the study of art from cultures outside its geographical boundaries and conventional timeframe? The bias in this interpretation of the subject opens up the questions of the importance of the canon in art history and how we view non-figurative, primitive, and naive art. ‘A global art history?’ considers a range of different examples of artistic practice from around the world, including the sculpture of the Dogon people of Mali and the calligraphy of Wu Zhen, who was active during the Yuan Dynasty (1271–1368). It also discusses what is meant by the ‘primitive’ arts of Oceania, Africa, and North and South America.

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Uranium and Thorium Resources of Estonia

Minerals ◽

10.3390/min10090798 ◽

2020 ◽

Vol 10 (9) ◽

pp. 798

Author(s):

Alvar Soesoo ◽

Johannes Vind ◽

Sigrid Hade

Keyword(s):

Rare Earth ◽

Radioactive Waste ◽

Black Shale ◽

Earth Element ◽

Geochemical Data ◽

Elemental Distribution ◽

Environmental Constraints ◽

Waste Dump ◽

Continental Scale ◽

Icp Ms

We provide a compilation of geology of uranium and thorium potential resources in the Ordovician black shale (graptolite argillite), Cambrian–Ordovician shelly phosphorite and in the secondary resources (tailings) of Estonia. Historical and new geological, XRF and ICP-MS geochemical data and ArcGIS modeling results of elemental distribution and tonnages are presented. The Estonian black shale contains 5.666 million tons of U, 16.533 Mt Zn, 12.762 Mt Mo, 47.754 Mt V and 0.213–0.254 Mt of Th. The Estonian phosphate resources, altogether about 3 billion metric tons of phosphate ore, contain about 147,000 to 175,000 tons of U. Rare earth element concentrations in the phosphorite ore average at 1200–1500 ppm of ΣREE. Thorium can also be a possible co-product. The mining waste dump at the Maardu contains at least 3650 tons of U and 730 tons of Th. The Sillamäe radioactive waste depository contains about 1200 tons of U and 800 tons of Th. Due to the neighboring geological positions, as well as environmental constraints and mining technologies, the black shale and phosphorite can be treated as a complex multi-resource, possibly at the continental scale, which needs to be extracted together.

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VIII.—Notes on the Pre-Glacial Rock-Platform on the Wexford Coast

Geological Magazine ◽

10.1017/s0016756800125312 ◽

1909 ◽

Vol 6 (11) ◽

pp. 507-508

Author(s):

F. R. Cowper Reed

Keyword(s):

Solid Rock ◽

East Coast ◽

Sand Dunes ◽

Marine Terrace ◽

The South ◽

The North ◽

The Subject ◽

The Village ◽

Nearly Continuous ◽

North And South

The occurrence of a pre-Glacial marine terrace and raised beach along the coast of the south of Ireland was described by Messrs. Wright & Muff in 1904, and its development in the eastern part of co. Waterford was the subject of two short papers by the author in 1907 in this Magazine. Messrs. Wright & Muff (op. cit.) observed the same raised beach only in the south-eastern portion of co. Wexford, so that its recognition this summer by the author further north along the east coast of Ireland deserves recording, for it has been traced for several miles to the north and south of Courtown Harbour, and its height, characters, and relations to the overlying deposits show that it is a continuation of the same feature. The first locality to be mentioned is about 3 miles to the south of the village of Courtown, where relics of it are preserved between Roney Point and Salt Rock; it is still more distinct as a rock-terrace a little further north at Pollshone Head and Breanoge Head, but in the bays between these points the conditions are not favourable for its exposure, as there are no rocky cliffs, only extensive sand-dunes stretching along the shore. From Courtown Harbour northwards for about 2 miles to Duffcarrig Rocks sand-dunes are similarly developed, forming a nearly continuous line of ridges rising to heights of over 50 feet. Thick drift deposits occur behind them, but no pre-Glacial cliff or platform is exposed. At Duffcarrig Rocks solid rock again appears forming the headland, and we can recognize remnants of the rock-cut shelf in a much eroded and fissured condition.

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NEGOTIATING “A WOMAN'S WORK”: PHILANTHROPY TO SOCIAL SCIENCE IN GASKELL'S NORTH AND SOUTH

Victorian Literature and Culture ◽

10.1017/s1060150311000258 ◽

2012 ◽

Vol 40 (1) ◽

pp. 83-97 ◽

Cited By ~ 2

Author(s):

Sarah Dredge

Keyword(s):

Social Science ◽

The Poor ◽

The Subject ◽

Woman's Work ◽

North And South

A review of F. D. Maurice'sLectures to Ladies on Practical Subjects in 1856 considered the question of “female visiting” among the poor with reference to Elizabeth Gaskell's North and South. Though agreeing that it is “the subject of much anxiety,” the reviewer illustrates the value of female philanthropic visiting with a reading of Gaskell's novel:

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