121 research outputs found
Polymorphism, Structure, and Nucleation of Cholesterol·H2O at Aqueous Interfaces and in Pathological Media: Revisited from a Computational Perspective
No full textWe revisit the important issues of polymorphism, structure, and nucleation of cholesterol center dot H2O using first-principles calculations based on dispersion-augmented density functional theory. For the lesser known monoclinic polymorph, we obtain a fully extended H-bonded network in a structure akin to that of hexagonal ice. We show that the energy of the monoclinic and triclinic polymorphs is similar, strongly suggesting that kinetic and environmental effects play a significant role in determining polymorph nucleation. Furthermore, we find evidence in support of various O-H center dot center dot center dot O bonding motifs in both polymorphs that may result in hydroxyl disorder. We have been able to explain, via computation, why a single cholesterol bilayer in hydrated membranes always crystallizes in the monoclinic polymorph. We rationalize what we believe is a single-crystal to single-crystal transformation of the monoclinic form on increased interlayer growth beyond that of a single cholesterol bilayer, interleaved by a water bilayer. We show that the ice-like structure is also relevant to the related cholestanol center dot 2H(2)O and stigmasterol center dot H2O crystals. The structure of stigmasterol hydrate both as a trilayer film at the air-water interface and as a macroscopic crystal further assists us in understanding the polymorphic and thermal behavior of cholesterol center dot H2O. Finally, we posit a possible role for one of the sterol esters in the crystallization of cholesterol center dot H2O in pathological environments, based on a composite of a crystalline bilayer of cholesteryl palmitate bound epirmrially as a nucleating agent to the monoclinic cholesterol center dot H2O form
Lessons from international experience with electricity market monitoring
No full textThe author first describes those features of the electricity supply industry that make a prospective market monitoring process essential to a well-functioning wholesale market. Some of these features are shared with the securities industry, although the technology of electricity production and delivery make a reliable transmission network a necessary condition for an efficient wholesale market. These features of the electricity supply industry also make antitrust or competition law alone an inadequate foundation for an electricity market monitoring process. The author provides examples of both the successes and failures of market monitoring from several international markets. More than 10 years of experience with the electricity industry restructuring process has shown that market failures are more likely and substantially more harmful to consumers than other market failures because of how electricity is produced and delivered and the crucial role it plays in the modern economy. Wholesale market meltdowns of varying magnitudes and durations have occurred in electricity markets around the world, and many of them could have been prevented if a prospective market monitoring process backed by the prevailing regulatory authority had been in place at the start of the market.Access to Markets,Markets and Market Access,Environmental Economics&Policies,ClimateChange,Health Economics&Finance
Techno-economic transition towards a hydrogen economy
No full textPhDThe research conducted is in the field of innovation and focuses on the UK energy sector. The key theme of the study is the transition towards a hydrogen economy with fuel cell technologies at the epicentre and takes into account the relevant scientific, technological, economic and policy issues. In order to provide an understanding of the factors that affect techno-economic transitions to alternative energy systems, the thesis investigates the historical transition processes such as the transition to electrification in the early 1900s and recent transitions to CCGT and renewable energy systems (wind, biofuels and solar) that have taken place since the late 1980s. As the developmental status of hydrogen technologies lay at the heart of these transitions, a thorough analysis of the hydrogen and fuel cell technologies, the R&D requirements, and innovations required in different scientific fields (including materials science) to develop these technologies is conducted. At the same time, as other factors such as sustainability, climate change and security of supply concerns can greatly affect the direction of the transition processes, that includes R&D activities and investment in alternative energy technologies, an overview of these factors is also provided. The analysis employs a new theoretical framework that combines two well established theories in the literature, Techno-economic Transitions and Large Technological Systems. By using this new framework, the technological transition towards a hydrogen energy system can be analysed at three levels, (global, national and local). The analysis is narrowed down to the local level in order to determine the timing of a transition in London and how it can form the foundation for a wider a transition at the national level based on alternative technologies
APLIKASI PENGOLAHAN DATA KEPEGAWAIAN PADA DINAS KEHUTANAN KABUPATEN OGAN KOMERING ILIR
No full textAi'syah, Neta F. 2015. Application Data Processing Officer at the Department of
Forestry Ogan Ogan Ilir.
Data processing personnel at the Department of Forestry Ogan Ogan Ilir still
using Microsoft Office software whose function is not yet particularly in view of
the processing of employee data, which includes employee data, a data list ranks
sequence, the data leave a letter and letters or official duties and making monthly
attendance report has not been automated. This will certainly hamper and require
a long time in processing the data. Therefore, the authors feel the need to build an
application that is more effective and efficient with the aim of getting an
application personnel data processing take place there. In addition, application
development is expected to provide benefits to the Polytechnic of Sriwijaya in
order to become a reference of knowledge in the field of the Information
Technology for all other students. The research methods used were interviews,
observation, and document analysis. In developing the system the author uses the
method waterfall (waterfall). The results of this study in the form of Application
Data Processing Officer at the Department of Forestry Ogan Ogan Ilir using the
programming language PHP and MySQL database.
Keywords: Applications, waterfall method (waterfall), staffing, Forestry,
database, PHP, MySQL
The transfer function analysis of various schemes for the two-dimensional shallow-water equations
No full textIn this paper various finite difference and finite element approximations to the linearized
two-dimensional shallow-water equations are analyzed. This analysis complements previous results for the one-dimensional case.The first author would like to thank the NPS Foundation Research program for its support of this research
Surprise as an Emotion: A Response to Ortony
No full text© The Author(s) 2022.We write in response to an article published in this journal by Andrew Ortony titled “Are All ‘Basic Emotions’ Emotions? A Problem for the (Basic) Emotions Construct.” The author claimed that “for all its elevated status as a basic emotion, surprise fails to satisfy the minimal requirements that [he] proposed for something to be an emotion, and if it is not an emotion, it cannot possibly be a basic emotion.” Although we acknowledge the concerns brought forth by Ortony, we respectfully disagree with his conclusion about surprise. To make a case against the assertion that surprise is valence-free, we summarize an extensive body of work showing that surprise is indeed valenced—in a specific manner (i.e., ambiguously valenced)—and that it meets all of Ortony’s criteria for an emotion. In other words, rather than being described as neither positive nor negative, this emotion is either positive or negative. We consider the data with respect to surprise as a basic emotion, and we dispute the definitions of basic emotions as “widely divergent.” Future work is needed to continue defining an emotion, and a basic emotion, but we believe this is a worthy effort toward shaping a still evolving field.11Nssciscopu
The Enoch-Metatron tradition in the kabbalah of Nathan Neta Shapira of Krakow (1585-1633)
No full textNathan Neta ben Shlomo Shapira (1585-1633) is the most famous kabbalist stemming from the Jewish intellectual environment of Poland. His major treatise, Megaleh Amuqot, is among the most complex kabbalistic texts ever written. It combines variegated strata of older mystical traditions, to which the author applies diverse, often obscure modes of interpretation. For this reason, Nathan Shapira has remained one of the least studied figures in modern scholarship, despite the fact that he is generally acknowledged as the most important early-modern Ashkenazi kabbalist, whose influence on later Eastern-European mystical circles is well attested. Although there are some general accounts of Shapira’s religious activity in Kraków, and references have been made to his startling mathematical mind-set, scholarship still lacks a thorough examination of his literary legacy, and a detailed evaluation of his contribution to the development of Jewish mystical thought. My dissertation aims to integrate Nathan Shapira’s kabbalah within a broad panorama of Jewish mystical traditions of the early modern period. It challenges the notion of the dominance of Lurianic ideas in Shapira’s thought, arguing for a more pluralistic perspective of the historical development of the kabbalistic tradition. Recently, Yehuda Liebes and Moshe Idel have raised the possibility that Nathan Shapira’s kabbalah may have belonged to a tradition that sprang from a multifaceted cultural milieu of Ashkenazi mysticism, consisting of at least two distinct major strands. Following this notion, I propose to challenge the common view that the Ashkenazi mysticism was a homogenous entity, whose influences effectively ceased after 13th century. On the contrary, I claim that the medieval mystical Ashkenazi ideas underlie much of Nathan Shapira’s kabbalah. In considering medieval Ashkenazi mysticism as Shapira’s formative background, I focus on the ‘Enoch-Metatron’ cluster of traditions, which I claim was as central to Shapira’s thought as it was to his Ashkenazi predecessors
A model to environmental monitoring based on glutathione-S-transferase activity and branchial lesions in catfish
No full textPolymer-Rich Dense Phase Can Concentrate Metastable Silica Precursors and Regulate Their Mineralization
No full textMultistep mineralization processes are pivotal in the
fabrication
of functional materials and are often characterized by far from equilibrium
conditions and high supersaturation. Interestingly, such ‘nonclassical’
mineralization pathways are widespread in biological systems, even
though concentrating molecules well beyond their saturation level
is incompatible with cellular homeostasis. Here, we show how polymer
phase separation can facilitate bioinspired silica formation by passively
concentrating the inorganic building blocks within the polymer dense
phase. The high affinity of the dense phase to mobile silica precursors
generates a diffusive flux against the concentration gradient, similar
to dynamic equilibrium, and the resulting high supersaturation leads
to precipitation of insoluble silica. Manipulating the chemistry of
the dense phase allows to control the delicate interplay between polymer
chemistry and silica precipitation. These results connect two phase
transition phenomena, mineralization and coacervation, and offer a
framework to achieve better control of mineral formation
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