105 research outputs found

    Nonresonant EFISH and THG studies of nonlinear optical property and molecular structure relations of benzene, stilbene, and other arene derivatives

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    D.c. elec. field induced 2nd-harmonic generation (EFISH) and 3rd-harmonic generation (THG) measurement results are reported on the intrinsic mol. hyperpolarizabilities of benzenes, stilbenes, and other arene derivs. Structure-property relations, as revealed by a comprehensive set of systematic measurements, are discussed. Issues concerning donor-acceptor strength; charge-transfer; transparency trade-off; conjugation planarity, length, and aromaticity; and heteroatom and side-group substitution effects are included

    Nonresonant EFISH And THG Studies Of Nonlinear Optical Property And Molecular Structure Relations Of Benzene, Stilbene, And Other Arene Derivatives.

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    D.c. elec. field induced 2nd-harmonic generation (EFISH) and 3rd-harmonic generation (THG) measurement results are reported on the intrinsic mol. hyperpolarizabilities of benzenes, stilbenes, and other arene derivs. Structure-property relations, as revealed by a comprehensive set of systematic measurements, are discussed. Issues concerning donor-acceptor strength; charge-transfer; transparency trade-off; conjugation planarity, length, and aromaticity; and heteroatom and side-group substitution effects are included

    Rabies in bat-eared foxes in South Africa

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    Rabies in bat-eared foxes was first recognized in South Africa in 1955 and is likely to have been derived from canine rabies introduced to South Africa in 1950. Since then it has become established in this species in the drier western half of the country and the south-western Cape so that rabies now occurs in bat-eared foxes adjacent to the peri-urban canine population of Cape Town. Peak incidence was recorded in the early 1980s and the incidence is seasonal with most cases occurring in winter.The articles have been scanned in colour with a HP Scanjet 5590; 600dpi. Adobe Acrobat XI Pro was used to OCR the text and also for the merging and conversion to the final presentation PDF-format.mn201

    Canid and viverrid rabies viruses in South Africa

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    Historical records suggest that in South Africa rabies was present in viverrids in the early 1800s. In the early 1950s a wave of canine rabies spread from Namibia through Botswana into the northern Transvaal and by 1961 a second front had penetrated south from Mozambique into Swaziland and northern Natal. Today, rabies is regularly confirmed in a number of canid and viverrid species in most regions of South Africa. A panel of anti-nucleoprotein monoclonal antibodies was used to examine 83 virus isolates from these species. Two major reaction patterns, one chiefly confined to viruses from canids and the other to viruses from viverrids, were obtained. In addition, some variation in the reaction patterns of viverrid viruses was observed and spill-over of viverrid virus into canids and vice versa was recorded. Rabies in South Africa appears to behave as two distinct disease entities.Proceedings of a workshop held at the Faculty of Veterinary Science, University of Pretoria, Onderstepoort, South Africa, 3-5 May 1993The articles have been scanned in colour with a HP Scanjet 5590; 600dpi. Adobe Acrobat XI Pro was used to OCR the text and also for the merging and conversion to the final presentation PDF-format.mn201

    The suitability of a rolled BHK₂₁monolayer system for the production of vaccines against the SAT types of foot-and-mouth disease virus. I. Adaptation of virus isolates to the system, immunogen yields achieved and assessment of subtype cross reactivity

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    In an examination of 34 southern African SAT-type foot-and-mouth disease viruses, all but 1 attained satisfactory levels of infectivity within 6 passages in rolled BHK₂₁monolayer cell cultures. However, there were marked differences between adapted viruses with respect to the mass of immunogen (146S material) produced. Several isolates which consistently produced levels ≥2 µg/ml were identified. In cross neutralization tests using post-vaccinal sera, SAT-1 and SAT-2 isolates showed considerable diversity and none of the viruses tested would be expected to produce a broad-spectrum response if incorporated into a vaccine. On the other hand, when 2 of the SAT-2 isolates were incorporated into the same vaccine a distinctly broader response resulted.The articles have been scanned in colour with a HP Scanjet 5590; 600dpi. Adobe Acrobat XI Pro was used to OCR the text and also for the merging and conversion to the final presentation PDF-format.lmchunu2014mn201

    South Atlantic Interbasin Exchanges of Mass, Heat, Salt and Anthropogenic Carbon

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    The exchange of mass, heat, salt and anthropogenic carbon (Cant) between the South Atlantic, south of 24°S, and adjacent ocean basins is estimated from hydrographic data obtained during 2008-2009 using an inverse method. Transports of anthropogenic carbon are calculated across the western (Drake Passage), eastern (30°E) and northern (24°S) boundaries. The freshwater overturning transport of 0.09 Sv is southward, consistent with an overturning circulation that exports freshwater from the North Atlantic, and consistent with a bistable Meridional Overturning Circulation (MOC), under conditions of excess freshwater perturbation. At 30°E, net eastward Antarctic Circumpolar Current (ACC) transport, south of the Subtropical Front, is compensated by a 15.9±2.3 Sv westward flow along the Antarctic boundary. The region as a whole is a substantial sink for atmospheric anthropogenic carbon of 0.51±0.37 PgC yr-1, of which 0.18±0.12 PgC yr-1 accumulates and is stored within the water column. At 24°S, a 20.2 Sv meridional overturning is associated with a 0.11 PgC yr-1 Cant overturning. The remainder is transported into the Atlantic Ocean north of 24°S (0.28±0.16 PgC yr-1) and Indian sector of Southern Ocean (1.12±0.43 PgC yr-1), having been enhanced by inflow through Drake Passage (1.07±0.44 PgC yr-1). This underlines the importance of the South Atlantic as a crucial element of the anthropogenic carbon sink in the global oceans

    Geographical and temporal distribution of SARS-CoV-2 clades in the WHO European Region, January to June 2020

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    We show the distribution of SARS-CoV-2 genetic clades over time and between countries and outline potential genomic surveillance objectives. We applied three available genomic nomenclature systems for SARS-CoV-2 to all sequence data from the WHO European Region available during the COVID-19 pandemic until 10 July 2020. We highlight the importance of real-time sequencing and data dissemination in a pandemic situation. We provide a comparison of the nomenclatures and lay a foundation for future European genomic surveillance of SARS-CoV-2.Peer reviewe
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