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Syn- and post-depositional influences on reservoir quality of the Aptian Dariyan Formation, eastern Persian Gulf
No full textThe Aptian Dariyan (Shuaiba) Formation, a major Cretaceous reservoir in the Middle East, remains poorly understood regarding the influence of depositional facies and diagenetic processes on reservoir quality. This research addresses the gap through an integrated analysis of facies, petrophysics, and geochemistry on a continuous, 104.5-m-long core from an oil/gas field in the eastern Persian Gulf. Employing fully automated techniques, we identified hydraulic flow units (HFUs). We classified nine carbonate facies into three distinct facies associations, arranged from shallowest to deepest: inner ramp (lagoon and shoals), shallow open-marine mid-ramp, and deep open-marine (outer ramp and intrashelf basin). These facies associations exhibit a stacking pattern delineating five third-order transgressive-regressive sequences. The identified HFUs include the barrier unit (HFU1), the baffle unit (HFU2), and the normal unit (HFU3), assessed based on lithological and petrophysical attributes. The normal unit, characterized by good storage capacity but poor to moderate flow capacity, highlights the complexity of reservoir quality. The Dariyan Formation is predominantly composed of mud-supported textures formed in warm, tropical waters. Additionally, late diagenetic cementation severely obstructed pore spaces, altered primary rock characteristics and reduced effective flow capacity
Peri-urban transformation as suburbanization:drivers and dynamics of urban expansion in African cities
No full textThe scale and pace of urban expansion across Africa has fuelled academic interest in transformations occurring on the periphery of African cities and how such transformations should be conceptualized. In this chapter, suburbanization is used as a conceptual lens for understanding the drivers and dynamics of ongoing transformations in the periphery of Dar es Salaam, Tanzania. The chapter focuses on incremental construction of residential housing by private individuals and households, which is a pervasive and widespread mode of urban expansion across African cities. The chapter draws on empirical insights from selected sites in Dar es Salaam's periphery, where new residential developments have emerged in the past decades. The residential nature of emerging developments, the strong functional integration with and orientation towards the city in residents’ economic activities, and their persistent efforts to improve services and infrastructure to perceived urban standards are important characteristics rendering suburbanization a meaningful conceptualization.The scale and pace of urban expansion across Africa has fuelled academic interest in transformations occurring on the periphery of African cities and how such transformations should be conceptualized. In this chapter suburbanization is used as a conceptual lens for understanding the drivers and dynamics of on-going transformations in the periphery of Dar es Salaam, Tanzania. The chapter focus on incremental construction of residential housing by private individuals and households, which is a pervasive and widespread mode of urban expansion across African cities. The chapter draws on empirical insights from selected sites in Dar es Salaam’s periphery, where new residential developments have emerged in the past decades. The residential nature of emerging developments, the strong functional integration with and orientation towards the city in resident’ economic activities and their persistent efforts to improve services and infrastructure to perceived urban standards are important characteristics rendering suburbanization a meaningful conceptualization
Differential age observations and their constraining power in cosmology
No full textWe derive the differential age signal valid for cosmic chronometers (passively evolving galaxies) in any space-time that satisfies the following assumptions: (i) The space-time has a metric with Lorentzian signature and the connection is the Levi-Civita connection; (ii) the cosmic chronometers are collectively well approximated as a geodesic and irrotational congruence of timelike worldlines in the space-time; (iii) light travels on null geodesics and caustics on the observer's past light cone can be ignored; (iv) the space-time is cosmological, meaning that isotropic and positive expansion degrees of freedom dominate over anisotropic and negative expansion degrees of freedom when viewed on sufficiently large scales in the frame of the cosmic chronometers. The main result of the paper is an expression for the differential age signal that is written in terms of line-of-sight averages of the expansion rate along individual null lines, thus providing a kinematic interpretation of the differential age signal applicable to cosmological space-times satisfying (i)-(iv). We explain how this result indicates that the differential age signal is a robust probe of the volume-average expansion rate in very general statistically homogeneous and isotropic space-time scenarios where other probes of the volume-average expansion rate tend to yield biased results. We argue that this unique property of the differential age signal makes it an ideal measurement for constraining the expansion history model independently.</p
General-relativistic resistive-magnetohydrodynamics simulations of self-consistent magnetized rotating neutron stars
No full textWe present the first general-relativistic resistive magnetohydrodynamics simulations of self-consistent, rotating neutron stars with mixed poloidal and toroidal magnetic fields. Specifically, we investigate the role of resistivity in the dynamical evolution of neutron stars over a period of up to 100 ms and its effects on their quasiequilibrium configurations. Our results demonstrate that resistivity can significantly influence the development of magnetohydrodynamic instabilities, resulting in markedly different magnetic field geometries. Additionally, resistivity suppresses the growth of these instabilities, leading to a reduction in the amplitude of emitted gravitational waves. Despite the variations in magnetic field geometries, the ratio of poloidal to toroidal field energies remains consistently 9∶1 throughout the simulations, for the models we investigated.</p
Asfergstenen og det gode selskab
No full textThe Asferg stone belongs to a group of Danish Viking Age runic stones, consisting as so often of a standard appraisal of the virtues of some late chieftain, but falling short with respect to one or two wordings that seem to make no sense. This has been ascribed to malpractice by the author or by the carver, casting doubt on the validity of the whole text as a witness of linguistic facts. I suggest a reading of the until now incomprehensible sequence kuþru : þin : that makes sense both runologically, linguistically and textually, namely as góðrǿðinn ’eloquent’. Thus, the outcast Asferg stone is promoted to the status of a reliable linguistic witness of Early Old Danish, including the disputed accusative word form bruþr ’brother’. I draw some consequences concerning the synchronic and diachronic shapes of kinship terms in Early Scandinavian, including the Malt stone form fauþr, read by me as fǫðr, but taken by several runologists to be a carving error for a two-syllable accusative form, e.g., faþur ’father’
Design, Synthesis, Biological Assessment, and Computational Analysis of Sulfathiazole Schiff Bases
No full textSulfathiazole-based Schiff Bases (SBs) have fascinated science with their broad-spectrum pharmacological properties and potential therapeutic applications. However, their efficacy and molecular interactions require further investigation. This investigation sought to synthesize sulfathiazole-based SBs and appraise their biological properties through characterization, in vitro assays, molecular docking, density functional theory, and ADME analysis. Sulfathiazole SBs synthesized by reacting sulfathiazole with various aryl aldehydes in equimolar ratios were characterized using UV-Vis, FTIR, CHNSO, H-1 NMR, and C-13 NMR spectroscopy and assessed for antibacterial, antifungal activities, antioxidant, in vitro antidiabetic, and anti-inflammatory potential using different assays. Molecular docking, DFT calculations, and ADMET analysis were conducted to scrutinize binding affinity, stability, and pharmacokinetic properties. The synthesized SBs exhibited notable antibacterial and antifungal activity. Compound 10b demonstrated strong antioxidant potential (IC50 = 55.93 +/- 0.56 mu g/mL), while compounds 7b, 9b, and 12b showed significant antidiabetic effects. Additionally, 7b (IC50 = 53.97 +/- 0.89 mu g/mL) and 9b (IC50 = 60.22 +/- 0.81 mu g/mL) displayed superior anti-inflammatory activity. Computational studies confirmed their potential as drug candidates. The integration of biophysical and chemical approaches provides a detailed understanding of their electronic structure, stability, and intermolecular interactions with biological targets. These results establish a strong foundation for further preclinical investigations, advancing their potential applications in drug discovery and development
Too Many, Too Improbable:Testing joint hypotheses and closed testing shortcuts
No full textHypothesis testing is a key part of empirical science and multiple testing as well as the combination of evidence from several tests are continued areas of research. In this article we consider the problem of combining the results of multiple hypothesis tests to (i) test global hypotheses and (ii) make marginal inference while controlling the k-FWER. We propose a new family of combination tests for joint hypotheses, called the ‘Too Many, Too Improbable’ (TMTI) statistics, which we show through simulation to have higher power than other combination tests against many alternatives. Furthermore, we prove that a large family of combination tests – which includes the one we propose but also other combination tests – admits a quadratic shortcut when used in a Closed Testing Procedure, which controls the FWER strongly. We develop an algorithm that is linear in the number of hypotheses for obtaining confidence sets for the number of false hypotheses among a collection of hypotheses and an algorithm that is cubic in the number of hypotheses for controlling the k-FWER for any k greater than one.</p
