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The Karangatian transgression of the Black Sea is a significant stage in its Pleistocene history. There is no consensus on the chronometric estimate of the age of this event. The paper presents the dating results for the Karangatian deposits cored from the Tuzla key section on the western coast of the Taman Peninsula. The mollusk shell composition of sediments indicates that the section reflects the peak phase of the transgression. A new absolute chronology bases on the dating by the method of infrared stimulated luminescence of feldspars. The distribution of credible intervals and the results of standard tests are in exact accordance with the ranges accepted in the operational practice of luminescence dating, thus the obtained results could be considered as reliable. The age of the Karangatian deposits of the Tuzla section matches with the time interval of 125-120 kaBP, which corresponds to the peak of the interglacial period (MIS 5e). The waters of the Karangat basin reached the section area about 125 kaBP, and the coastalmarine deposition began at 3.5 m AMSL. The basin level reached 5,3 m AMSL in 120 ka BP, the rise of 1,8 m during 5 thousand years. After 120 ka BP, the local marine sedimentation was insignificant. The subaerial deposition stage in the western part of the Taman Peninsula began about 100 ka BP. The section contains a loess-soil series with three layers of buried soils. An additional geochronological study of the upper part of the section will determine the age of these layers and reconstruct the substages of subaerial deposition stage of the Late Pleistocene regional history.

ObjectivesThe aim of this study was to assess whether a risk assessment and managed risk approach to contact tracing was practical and feasible at the Gran Canaria Lopesan Open 2021 and could inform further pilot work regarding disease transmission during elite sporting events.MethodsThis prospective cohort study included all international attendees. All participants required a minimum of one negative reverse transcriptase PCR (RT-PCR) test prior to travelling to each tournament. High-risk contacts were isolated for 10 days. Moderate-risk contacts received education regarding enhanced medical surveillance, had daily rapid antigen testing for 5 days, with RT-PCR day 5, mandated mask use and access to outside space for work purposes only. Low-risk contacts received rapid antigen testing every 48 hours and PCR testing on day 5.ResultsA total of 550 persons were accredited and were required to undergo RT-PCR testing before the event. Two of these tests were positive (0.36%). Of these, case 1 had 1 high, 23 moderate and 48 low-risk contacts. Case 2 did not have any significant travel history within 2 days of positive test and had one high-risk contact. There were no further positive tests on site in the wider cohort of attendees, from a total of 872 RT-PCR and 198 rapid antigen tests.ConclusionsThis pilot study showed it is practical, feasible and well accepted to provide enhanced (daily) virus testing and risk-mitigating measures at a professional golf event. Further study is required to assess the efficacy of these interventions; however, no transmission was found in this pilot study.

Udgivelsesdato: 2009

ALLOW me space for a word or two in reply to Mr. Wallace and Mr. Butler's observations on my papers on Mimicry and Hybridisation.

Mr Murray commences with aresuméof what is known regarding the growth of eyes in insects, from the first stage in the larva, when many are without eyes, till their exclusion from the chrysalis, when they usually appear well provided with compound eyes. He reviews the nervous system in different species, and gives some details as to those species which live in dark places, and which have small eyes and a less-developed optic nerve, contrary to what one would at first suppose. The next portion of his paper is devoted to explaining his views of the structure of the eye in insects, and its relation to the eye in vertebrate animals.

In a paper which I read last year before this Society, “On the Structure and Functions of the Branchial Sac of the Simple Ascidise,” I stated that I had fed and injected ascidiæ with indigo and other coloured sea-water, and that in those so fed, the coloured material was never found on the exterior of the sac, but always deposited on the inner wall, and that injection by the mouth into the sac failed to push the coloured matter through its walls, except by rupturing them.These experiments were not isolated or few in number. I showed the results to various friends—among others, Professor Goodsir, Dr Wright, and Dr Cleland—and never, in any of the experiments which I made, did a single instance occur of the indigo passing through the stigmata of the sac; and, in that paper, I naturally reasoned from this fact.

The object of this paper was to determine whether the pediculi infesting the different races of man were of the same or of distinct species, and thereby to ascertain whether any inference could be drawn therefrom, bearing upon the disputed question of the unity of the human species.

The author regards Mr. Darwin9s theory of Coral islands as imperfect, from not recognizing the fact of a gradual diminution of the amount of water on the face of the earth. He objects to Mr. Darwin9s explanation of the mode in which the islets appear above the water, namely, the dash of the waves breaking the reef, and their wash piling up the debris until it forms dry land; and he quotes the objections of M. de Rochas to the same theory. The opinion of the latter author was that the islands had been raised by a movement of upheaval; but Mr. Murray considers this still more improbable, as we are dealing with a large number of islands scattered over an immense space, and all at one uniform level, only a little above the surface of the sea; while the amount of all known elevations is irregular, and increases towards some axis of elevation. Mr. Murray believes the true explanation to be that the sea is gradually diminishing in volume; and he regards the Coral islets as a proof that it is so, at any rate, he remarks that if we apply this condition of things to an area of coral reefs, all as near the surface of the sea as the polyps can make them, we should have a result exactly in accordance with the state of things now existing in Polynesia. The author then states that the fossils of the older formations being wholly marine, and the thickness of those formations largely exceeding those of later periods, afford evidence in support of the view that the globe was then enveloped in water. In opposition to Sir Charles Lyell9s view, that the proportion of dry land to sea was always the same, and the volume of the land above the sea a constant quantity, he maintain that the latter is constantly increasing, and that both the mean and the extreme depth of the sea are constantly diminishing; and he believes the cause of this constant diminution to be the extreme affinity which water has for the constituent elements of minerals. Mr. Marray is careful to state his admission that whether there be more or less free water now than at the beginning, there can be neither more nor less of the elementary constituents out of which it is composed. He then refers to volcanic action as showing that the process of the cooling of the earth9s crust and the attendant abstraction of water the surface are still going on; and he remarks that although not a particle of water can be present in the molten mineral core of the earth, yet every particle of that core will, when cool, be largely composed of water—and that therefore the amount of water on the surface of the earth must continue to diminish until the earth is cool or the water wholly absorbed. In conclusion, he quotes the case of the Moon as one in which this process of absorption of not only its water, but of its atmosphere also, has been brought to a conclusion.

The changes in local coordination about uranium and nickel that occur during the formation and treatment of a nickel–uranium oxide catalyst have been followed by EXAFS and XANES. Although the changes which are observed in the nickel K-edge EXAFS when the active catalyst is passivated or exposed to air are quite small, more significant changes are observed in the uranium L3-edge EXAFS data when the samples are subjected to similar treatments. The uranium oxide lattice type, which is adopted at various stages of the preparation and treatment, has been determined by a qualitative comparison of the data with those recorded from uranium oxides. It is apparent that whilst the active and passivated catalysts have a uranium coordination similar to that of UO2, exposure of the active catalyst to air causes a change in structure in which the uranium coordination environment resembles that of α-U3O8.