Киев-Еганское месторождение нефти

Рассматривается геологическое строение Киев-Еганского нефтяного месторождения Томской области, описываются его нефтеносные объекты, отмечается значение данного месторождения с точки зрения поисков нефтяных и газовых месторождений в восточном направлении

Cellular expression and crystal structure of the murine cytomegalovirus MHC-Iv glycoprotein, m153

Mouse cytomegalovirus (MCMV), a β-herpesvirus that establishes latent and persistent infections in mice, is a valuable model for studying complex virus-host interactions. MCMV encodes the m145 family of putative immunoevasins with predicted MHC-I structure. Functions attributed to some family members include downregulation of host MHC-I (m152) and NKG2D ligands (m145, m152, m155) and interaction with inhibitory or activating NK receptors (m157). We present the cellular, biochemical and structural characterization of m153, which is a heavily glycosylated homodimer, that does not require β2m or peptide, and is expressed at the surface of MCMV-infected cells. Its 2.4 Å crystal structure confirms that this compact molecule preserves an MHC-I-like fold and reveals a novel mode of dimerization, confirmed by site-directed mutagenesis, and a distinctive disulfide-stabilized extended amino terminus. The structure provides a useful framework for comparative analysis of the divergent members of the m145 family

The dynamic cusp at low altitudes: A case study combining Viking, DMSP, and Sondrestrom incoherent scatter radar observations

A case study involving data from three satellites and a ground-based radar are presented. Focus is on a detailed discussion of observations of the dynamic cusp made on 24 Sep. 1986 in the dayside high-latitude ionosphere and interior magnetosphere. The relevant data from space-borne and ground-based sensors is presented. They include in-situ particle and field measurements from the DMSP-F7 and Viking spacecraft and Sondrestrom radar observations of the ionosphere. These data are augmented by observations of the IMF and the solar wind plasma. The observations are compared with predictions about the ionospheric response to the observed particle precipitation, obtained from an auroral model. It is shown that observations and model calculations fit well and provide a picture of the ionospheric footprint of the cusp in an invariant latitude versus local time frame. The combination of Viking, Sondrestrom radar, and IMP-8 data suggests that we observed an ionospheric signature of the dynamic cusp. Its spatial variation over time which appeared closely related to the southward component of the IMF was monitored

Linking integrated reporting quality with sustainability performance and financial performance in South Africa

CITATION: Mans-Kemp, N. & Van der Lugt, C. T. 2020. Linking integrated reporting quality with sustainability performance and financial performance in South Africa. South African Journal of Economic and Management Sciences, 23(1):a3572, doi:10.4102/sajems.v23i1.3572.The original publication is available at https://sajems.orgBackground: Ten years have lapsed since the launch of the International Integrated Reporting Council. Stakeholders increasingly question whether integrated reporting (IR) meets the objectives of decision-usefulness and accountability. Aim: The primary objective of this study was to assess the usefulness of IR by examining the interrelations between the integrated reporting quality (IRQ), sustainability performance and financial performance of listed companies in South Africa. Setting: The study is conducted in the country where integrated reporting is most established. The links between the IRQ of the Top 100 companies listed on Johannesburg Stock Exchange and their environmental, social and corporate governance (ESG) scores and multiple financial indicators are investigated over the period 2013 to 2018. Method: The EY Excellence in Integrated Reporting Awards was used as a metric to determine the sample companies’ IRQ. These awards were ranked according to four categories, namely ‘progress to be made’, ‘average’, ‘good’ and ‘excellent’. Sustainability (ESG scores) as well as financial performance data (accounting-based and market-based variables) were sourced from Bloomberg. The panel dataset was analysed by conducting a mixed-model analysis of variance and panel regressions. Results: A high level of IRQ was found to be significantly associated with high levels of environmental, social and corporate governance performance, as well as high earnings per share and high leverage. Conclusion: IR appears to strengthen managerial efficiency and legitimacy in the eyes of debt capital providers in South Africa, while equity capital providers do not provide a clear signal of approval.https://sajems.org/index.php/sajems/article/view/3572Publisher's versio

Total Synthesis of the Proposed Structure of Briarellin J

The total synthesis of the originally proposed structure of briarellin J is reported in 15 steps from a known compound and in 23 steps from readily available materials. Key reactions include an exo selective intramolecular Diels-Alder and a substrate controlled hydroboration. Discrepancies in the spectroscopic data of the synthetic and natural material led to a revision of the assigned structure

Weak Acid Permeation in Synthetic Lipid Vesicles and Across the Yeast Plasma Membrane

We present a fluorescence-based approach for determination of the permeability of small molecules across the membranes of lipid vesicles and living cells. With properly designed experiments, the method allows us to assess the membrane physical properties both in vitro and in vivo. We find that the permeability of weak acids increases in the order of benzoic > acetic > formic > lactic, both in synthetic lipid vesicles and the plasma membrane of Saccharomyces cerevisiae, but the permeability is much lower in yeast (one to two orders of magnitude). We observe a relation between the molecule permeability and the saturation of the lipid acyl chain (i.e., lipid packing) in the synthetic lipid vesicles. By analyzing wild-type yeast and a manifold knockout strain lacking all putative lactic acid transporters, we conclude that the yeast plasma membrane is impermeable to lactic acid on timescales up to ∼2.5 h.BT/Industrial Microbiolog

Total Syntheses of (+)-Vigulariol and (−)-Sclerophytin A

The total synthesis of (+)-vigulariol and (−)-sclerophytin A are reported in 15 steps and 16 steps, respectively, from a known compound. The flexible, readily scalable synthetic strategy allows for rapid construction of a critical tricyclic intermediate and is demonstrated via the synthesis of these two marine natural products. A key reaction in this synthetic protocol is a combination Wittig/intramolecular Diels-Alder cycloaddition