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[Display omitted] • Direct reduction of ester to ether requires Brønsted acid site close to metal site. • Strong Brønsted acid sites promote cleavage of the C O bond of ester. • Kinetically relevant C O bond cleavage on Brønsted acid sites for ether formation. Esters represent an important class of reagents and intermediates for the production of fine chemicals and polymers. In prior studies of homogeneous catalysis, molecular complexes have been reported to selectively cleave either carbonyl C O or acyl C O bonds of ester to ether or alcohols, respectively. In contrast, reactions of esters and H 2 upon heterogeneous catalysts typically cleave acyl C O bonds and produce alcohols. Here, we demonstrate that the proximity of Brønsted acid sites to Pd nanoparticles and the thermodynamic strength of these Brønsted acid sites influence the rates and selectivities toward C O bond cleavage pathways either to ethers or alcohols during reactions of esters over bifunctional solid catalysts. The combined results from rate measurements as functions of H 2 pressure, ester conversion, and methods to combine Pd nanoparticles and acidic supports; kinetic isotope effects; in situ Brønsted acid site titrations; and calorimetric assessments of Brønsted acid strength provide evidence for bifunctional pathways that require proximity between Brønsted acid sites and Pd atoms to form ethers. These findings suggest that Brønsted acid sites near Pd nanoparticles and with lower deprotonation energies promote the direct reduction of esters to ethers by cleaving the carbonyl C O bond. Taken together, these data indicate that direct reduction of esters to ethers involves the hydrogenation of the ester reactant to form hemiacetal at Pd nanoparticles, followed by dehydration of the hemiacetal at proximal acid sites, and subsequent hydrogenation of the enol ether. In comparison, hydrogenolysis of acyl C O bonds of the ester reactant involves the reaction of a hydrogenated intermediate (plausibly hemiacetal) upon Pd nanoparticles to form the corresponding alcohol and aldehyde products. Among the materials examined, Pd nanoparticles supported on WO 3 catalyze the direct reduction of esters and lactones to corresponding ethers and remain stable over extended periods of time on stream (∼42 h). These findings offer a foundation for further design and improvement of heterogeneous catalysts for the selective reduction of esters and other challenging hydrogenations. [ABSTRACT FROM AUTHOR]

Since the rise of the first cryptocurrency in 2008 until 2022, we can observe significant price volatility of cryptocurrency coins, periodic decline in prices for cryptocurrency coins and their growth, changes in the volume of cryptocurrency coin trading. Investors perceive cryptocurrency as an alternative (hedging) investment, a means of circulation and a measure of value. They increasingly use it in global socio-economic and military-political crises. Studying the price dynamics of cryptocurrencies during the active phase of the Covid-19 pandemic in 2020-2021 (the previous pandemic was a hundred years ago – the so-called "Spanish flu") and the conventional Russian-Ukrainian war of 2022 (and a similar scale of conflict after World War II 77 years), we will try to conduct an economic analysis to examine how these crisis factors affected the dynamics of prices for major cryptocurrencies – Ether and Bitcoin. Highlighting previously unresolved parts of the overall problem. The influence of various global factors on the price of cryptocurrencies has been insufficiently studied due to the short historical period of cryptocurrencies existence. We will try to identify the dependence of cryptocurrencies' values dynamics on the presence of global positive or negative factors (pandemics, wars, etc.). The purpose and objectives of the study. The main objectives of the article are to prove that the presence of global positive or negative factors (pandemics, wars, etc.) has a significant impact on the structure of investment, in general, and the price dynamics of cryptocurrency units in particular. Methods. In the research process, in particular, the following methods were used: analysis – to reveal the object and subject of research; abstract-logical (theoretical generalizations and formulations of conclusions concerning the impact of the Covid-19 pandemic in 2020-2021 and the conventional Russian-Ukrainian war in 2022 on the value of the cryptocurrency Bitcoin). Results. The significant impact of the Covid-19 pandemic in 2020-2021 and the conventional Russian-Ukrainian war in 2022 on various components of the financial market has been revealed. It was found that extreme socio-economic events provoke a fall in the stock market, do not provoke significant changes in the gold market and stimulate the major cryptocurrencies value growth. Bitcoin and Ether price dynamics have been shown to be highly correlated and are more suitable as short-term safe investment havens for pandemic or conventional war events than gold for economic operators who want to save and increase their savings. Conclusions. Due to the significant increase in the price of Bitcoin and Ether cryptocurrencies during the peak periods of the Covid-19 pandemic in 2020-2021 and the conventional Russian-Ukrainian war in 2022, cryptocurrencies are an effective and appropriate tool for investing and saving financial resources in the short term. [ABSTRACT FROM AUTHOR]

In this paper, we investigate the role of Bitcoin as a safe haven against the stock market losses during the spread of COVID-19. The performed analysis was based on a regression model with dummy variables defined around some crucial dates of the pandemic and on the dynamic conditional correlations. To try to model the real dynamics of the markets, we studied the safe-haven properties of Bitcoin against thirteen of the major stock market indexes losses using daily data spanning from 1 July 2019 until 20 February 2021. A similar analysis was also performed for Ether. Results show that this pandemic impacts on the Bitcoin status as safe haven, but we are still far from being able to define Bitcoin as a safe haven. [ABSTRACT FROM AUTHOR]

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The direct α-Csp3 –H functionalization of simple ethers is a vital strategy among radical reactions. This review discusses their applications according to the starting materials: (1) reactions with alkenes or alkynes; (2) reactions with other unsaturated compounds; and (3) reactions with nucleophilic partners. Mechanisms like radical addition, C–H activation, elimination, metal-catalyzed coupling, cyclization, oxidation, and rearrangement will be analyzed herein. 1 Introduction 2 Reactions with Alkenes or Alkynes 3 Reactions with Other Unsaturated Compounds 4 Reactions with Nucleophilic Partners 5 Oxidation of Ethers 6 Conclusions [ABSTRACT FROM AUTHOR]

This work discusses the construction of the concept field in the electromagnetic theory, in the second half of the 19th century, in Great Britain. The representation of fields by tubes was so fundamental to the british thoght that it motivated research led by William Thomson, later refined by Joseph John Thomson, to represent matter by atoms composed of tubes, which culminated in J. J. Thomson's model of the atom. [ABSTRACT FROM AUTHOR]

A series of 2‐ethylhexyl alkyl ethers (EHAE) are synthesized from palm‐based esters via a one‐step reaction under mild reaction conditions for potential usage as biolubricant. In this work, 2‐ethylhexyl esters with varying fatty acid chain lengths are reacted with 1,1,3,3‐tetramethyldisiloxane (TMDS), catalyzed by indium bromide (InBr3) at 40 °C to afford EHAE with lauryl, palmityl, stearyl, and oleyl alkyl chain with 55–68% isolated yield. These compounds are characterized using Fourier‐transform infrared (FTIR) and NMR spectroscopic methods and are evaluated for their viscosity, thermal, cold‐flow, oxidative, and anti‐wear properties. The synthesized EHAEs demonstrate low viscosity (1.65–2.55 cSt at 100 °C) with excellent viscosity indices (130–182). These EHAEs show comparable wear scar diameter (0.6–1.0 mm) in comparison with commercial mineral oil base stock (group I SN150) in the four‐ball wear test. Thermal‐oxidative investigation of the EHAE reveals that the thermal degradation temperatures are in the range of 200–250 °C and oxidation onset temperatures are between 165 and 184 °C. Among the EHAEs, 2‐ethylhexyl lauryl ether with the shortest alkyl chain has the lowest pour point of −27 °C. The physicochemical properties of synthesized EHAEs indicate that they are potential as biolubricant base stocks. Practical Applications: The EHAEs produced from this work exhibit promising physicochemical and lubricity properties, which offer great potential to be used as lubricant base stock especially for internal engine oil application. [ABSTRACT FROM AUTHOR]

Vibrational spectra of the methyl groups in CH3SH, CH3SCH3, CH3OH, and CH3OCH3 monomers were measured to analyze their complex features as a result of bend/umbrella‐stretch Fermi resonance. Multiple bands were recorded between 2800–3000 cm−1 associated with the vibrations of the methyl groups in CH3OH, and CH3OCH3. On the other hand, the corresponding spectra of CH3SH and CH3SCH3 are relatively simpler with main peaks between 2900 to 3000 cm−1. Theoretical ab initio anharmonic algorithm using six normal modes on a methyl group with potential energy surface at CCSD(T)‐F12/aug‐cc‐pVTZ quality is able to account for all the experimentally observed features across these four species. In CH3SCH3 and CH3SH, all three CH stretch fundamentals are above 2900 cm−1, but the fundamental of umbrella mode is lower than 1350 cm−1, thus only the overtone states of two bending modes are able to borrow sufficient intensities. In CH3OCH3 and CH3OH, umbrella modes have frequencies similar to the bending modes and the CH stretch fundamentals are red‐shifted to 2850–2950 cm−1 leading to more complex vibrational features due to better energy‐matching condition. [ABSTRACT FROM AUTHOR]

The article of Apffel et al. [Nature 585, 48 (2020)] reported on an experiment that produced the sight of two miniature sailboats floating upside down to each other on the two sides of a layer of glycerol that was levitated by high frequency vibrations. The vessel on the underside of the glycerol is a remarkable display of the results of simulated gravity caused by vibrations. The present article considers this and other experiments on simulated gravity and finds that they provide support for the flowing aether concept of the cause of gravity. [ABSTRACT FROM AUTHOR]

The majority of crypto-currencies are pseudo-anonymous in a sense that they are traceable through their hashes. Very few crypto-currencies really provide strict anonymity (i.e., un-linkability) for exchanges. This article investigates the link between strictly anonymous crypto-currencies (Moreno (XMR), Dash (DASH), Verge (XVG) and the dynamics of the two most important pseudo-anonymous crypto- currencies (Ether/Bitcoin) between 2015 and 2020. Our empirical analysis found a significant relationship between three of these anonymous crypto-currencies (XMR, DASH and XVG) and Bitcoin/Ether. Through an ARCH and GARCH-based econometric technique, we identify a structural break in all these crypto-currencies’ dynamics implying the need to study two distinct sub-periods (before/after 17 December 2017). Interestingly, the dynamics of these assets behave differently in the two identified regime. The conditional correlations between crypto-currencies are stronger after the structural break (during the decreasing market) than before (increasing trend). These results indicate that, before the structural breaks, anonymous crypto-currencies could have been considered as good assets for diversification purposes but their diversifying properties cannot be observed in decreasing markets (i.e., after the 17Dec 2017). Our study identifies DASH as a key crypto-currency since this digital asset could be involved in the dynamics of Bitcoin and Ether in our two periods of study. [ABSTRACT FROM AUTHOR]

The Ether Day, a key moment in the history of mankind, commemorates its 175th anniversary on 16 October 2021. On that day the dentist William T. G. Morton successfully gave the first public ether anesthesia in Boston. From then on it was possible to save people from pain with justifiable risk and at the same time to protect them from psychological damage by inducing unconsciousness. The German philosopher Peter Sloterdijk, one of the most renowned and effective philosophers of our times, deduced that from then on humans, to some extent, had a right to unconsciousness when in psychophysical distress. This postulate unfolded from his concept of "anthropotechnics" developed around 1997, meaning the idea of treating human nature as an object of possible improvements. According to Sloterdijk, in favorable cases a synthesis of man and technology can result in a significant improvement of human capabilities in the sense of "enhancement", i.e. an increase, an improvement or even an expansion of intellectual, physical or psychological possibilities, as it were in a transgression of the human (so-called transhumanism). Man should go into vertical tension, i.e. strive for higher aims and exploit his inherent potential, he should not dwell in the horizontal. This is not meant as an appeal but as an imperative: "You must change your life!". In this context modern anesthesia may prove helpful: be operated on by others in order to undergo an enhancement. Or, in its most extreme form, the operation in the "auto-operational curved space", a person can even operate on himself as has been dramatically demonstrated by Rogozov, a young Russian physician and trainee surgeon who successfully performed a self-appendectomy under local anesthesia at the Novolazarevskaya Antarctic Station in 1961; however, the implementation of this idea is a long way off. On the one hand, many countries lack qualified personnel in sufficiently large numbers to perform even vital operations with patients under anesthesia. On the other hand, over the decades it has become clear that anesthesia is obviously beneficial for mankind in that it offers relief from pain and psychological stress but that it can also often show its dark side: substance abuse, use of anesthetics in torture and in executions. In addition, the role of anesthetics in resuscitation, palliative care, and allaying executions is unclear or controversial. Finally, the necessary formal legal steps to acknowledge a "human right to unconsciousness" have not yet been implemented. [ABSTRACT FROM AUTHOR]

Edmund T. Whittaker's second edition of his A History of the Theories of Aether and Electricity is famous for his treatment of Einstein as an almost irrelevant character in the emergence of what he called "the relativity theory of Poincaré and Lorentz." Historians of science have given a number of explanations, which include Whittaker's scientific conservatism as an old classical physicist, his commitment to the ether, the pre-eminent role he attributed to mathematics over physics, and foundational philosophical disagreements, to name a few. And in the background, often more implicit than forthright, the accusation of antisemitism looms over Whittaker. In this paper I intend to shed new light on this controversy by taking into consideration the abundant correspondence between Whittaker and his son preserved in the archives of the Fisher Library, University of Toronto. With it, we will get a more complex and personal view of the context in which his attempt at dethroning Einstein took place. Together with the abovementioned reasons, this correspondence shows that the problematic status quo of general relativity in the early 1950s, a period that has been described as the low-mark of general relativity, was very influential in the historical treatment he gave to Einstein. This is an aspect hardly mentioned in the historical work on this controversy and, from this correspondence, it appears to be central to understanding Whittaker at the time of drafting the new History. His possible antisemitic bias will also be addressed, though with the insufficient information on this subject the matter cannot be settled. [ABSTRACT FROM AUTHOR]

Each type of Coulomb (Newton) charge corresponds to a kind of Coulomb (Newton) mass. Such a mass-charge duality principle explains the availability of the united rest mass and charge in a neutrino equal to all its mass and charge consisting of the electric, weak, and strong components and the range of other innate components. A neutrino itself, similarly to all other quantum matter with Coulomb (Newton) mass and charge, testifies hereby in favor of a kind of mononeutrino with magnetocoulomb (magnetonewton) rest mass and charge equal to all its mass and charge including the magnetoelectric, magnetoweak, and magnetostrong parts and the range of other innate parts. We discuss a theory in which symmetry between electricity and magnetism comes forward at the level of a grand unification mathematical logic as the defined symmetry between gravity and magnetogravity within the same allgravity responsible for all that in a curved space-time. This allgravity relates a graviton and a monograviton as a consequence of force unification forming a single allgraviton. Thereby, it establishes a set of forces and the role of mass and charge in their formation and thus directly reveals the most diverse properties of a curved space that have remained hitherto latent. [ABSTRACT FROM AUTHOR]

In an academic environment devoted to a progressive anglicisation of the scientific debate, how can we achieve exhaustive results – within historicophilosophical analysis – having to deal with sources written in a multiplicity of languages, including the specific vocabularies of obsolete or extinct epistemological systems? The present paper questions the possibility of creating specific lexicons, both period- and author-oriented, as dedicated research tools for historians of science.

The middle of the 19th century was a period when, despite the loss of state independence, magazines addressed to medical circles began to be established and developed on Polish lands. This happened, among others, in Warsaw, where "Pamiętnik Towarzystwa Lekarskiego Warszawskiego" (“Diary of the Medical Society of Warsaw”) and "Tygodnik Lekarski” (“Medical Weekly”) were published. They presented many novelties - both diagnostic and therapeutic - which included the introduction of general anaesthesia into common medical practice. The articles played a role of a practical transfer of knowledge. What is undoubtedly interesting is the very fast flow of information between the countries of Western Europe and the Polish lands, given the technical possibilities at that time.

Kant’s dissertation for the Master’s degree Succinct Exposition of Some Meditations on Fire was written in Latin in 1755 as a sample (specimen) preceding a Master’s exam, but its first printing did not appear until 1838. What is the relevance of this Master’s dissertation for historical and philosophical studies? To answer this question I analyse the structure and give a brief summary of the dissertation, look at the history of its writing and try to identify the place of this work among Kant’s other papers on natural philosophy. I then demonstrate that Kant’s concept of ether as an elastic matter of fire, heat and light containing the forces of attraction and repulsion originates in the dissertation On Fire. I identify the provisions in Kant’s early works which he later develops in the Master’s dissertation and establish continuity between the text of On Fire and the so-called Physical Monadology, draw parallels between the ideas enunciated by Kant in his first dissertation and the interpretation of ether in the printed works that followed. Finally, I put forward the hypothesis of the heuristic potential of the On Fire treatise for the analysis of Kant’s manuscript legacy. Perhaps this dissertation will enable researchers to clear up some tangled propositions in Kant’s Opus Postumum. However, a series of further studies is needed to verify the hypothesis.

The research employs WLS Regression for examining the main determinants of the ICO profitability in the crowdfunding stage. The variables are divided into three main categories: financial and technological aspects, and the ICO characteristics, with the aim of verifying which parts most influence the funds raised. The results imply that financial and technological aspects might indeed have an impact on the ICO profitability. The key factors covered are the opensource code availability and the preset hard cap. Overall, the econometric analysis discloses that the amount raised during the ICO is not affected by the availability of a white paper and pre-sales, even though some researchers argue differently.

Argument: The aim of this article is to make a case for the pertinence of a biographical approach to the history of scientific objects. I first lay out the rationale of that approach by revisiting and extending my earlier work on the topic. I consider the characteristics of scientific objects that motivate the biographical metaphor, and I indicate its virtues and limitations by bringing out the positive and negative analogies between biographies of scientific objects and ordinary biographies. I then point out various ways in which scientific objects may pass away and argue that their demise should be conceptualized as a process. Finally, I sketch the history of the concept of "ether" in nineteenth and early twentieth century physics and suggest that it lends itself particularly well to a biographical treatment. To that effect, I discuss the identity, heuristic character, and recalcitrance of the ether and examine the reasons that may have led to its passing. [ABSTRACT FROM AUTHOR]

Argument: In this paper I follow the demise of the ether in the first half of the twentieth century to show how the first obituaries of the ether were instrumental in creating an object with specific and largely simplified properties related to, but different from, nineteenth-century ethers. I suggest that writing the history of dead objects (or objects an author wants to be dead) is not epistemologically neutral but, on the contrary, it involves a reformulation of the object itself. I show that this was indeed the case with the ether: those arguing for its demise in the early twentieth century tended to overlook as irrelevant one of the ether's most important properties, namely being the seat for the transmission of electromagnetic waves. Instead, they emphasized the contradictions between other properties of previous ether(s), so as to advocate for its disappearance. [ABSTRACT FROM AUTHOR]

Have you ever wondered about the first surgeons who operated on patients without anesthesia on fully conscious patients, screaming in excruciating agony and being held captive by their assistants? Fortunately, substances were being discovered that can cause pain when not felt. This manuscript will summarize the following first attempts at painless surgery. [ABSTRACT FROM AUTHOR]

BACKGROUND: Spirodiclofen is a spirocyclic tetronic acid‐type acaricidal agent. Nowadays, serious pests resistance to spirodiclofen and cross‐resistance to other acaricides has appeared. To overcome pests resistance and discover new potential agrochemicals, a series of ether derivatives were prepared based on spirodiclofen as a lead compound. Their pesticidal activities were investigated against three typically agricultural pests, Mythimna separata Walker, Aphis citricola Van der Goot and Tetranychus cinnabarinus Boisduval. RESULTS: Four steric structures of compounds 5e, 5f, 5i and 5j were determined by single‐crystal X‐ray diffraction. Against T. cinnabarinus, compounds 5b, 5f and 5l exhibited potent acaricidal activity, and their good control effects in the glasshouse were observed when compared with spirodiclofen, especially the control efficiency of compound 5b was comparable to that of spirodiclofen; against M. separata, compound 5j showed > 1.8‐fold potent insecticidal activity of spirodiclofen; against A. citricola, compounds 5d and 5j displayed > 2.0‐fold potent aphicidal activity of spirodiclofen. The relationships between their structures and agricultural activities were also discussed. CONCLUSION: Compounds 5b and 5d could be further studied as acaricidal and aphicidal agents, respectively; compound 5j can be considered as a lead compound for the insecticidal and aphicidal activities. This will pave the way for future application of these derivatives as pesticide substitutes for spirodiclofen. © 2021 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Herein an efficient approach to produce functional polypropylene via solvent assisted solid-phase grafting process is reported, in which acrylic acid, methyl methacrylate and maleic anhydride are used as multi-monomers, 2,2′-azobis(2-methylpropionitrile) as initiator and ether as swelling solvent and carrier. The effects of various factors such as the swelling solvent species and dosage, swelling time and temperature, monomer and initiator concentrations, reaction time and temperature, nitrogen flow rate and the stirring speed on the grafting percentage and grafting efficiency were investigated. To verify the polar species was grafted onto polypropylene, the resulted polymers were characterized by Fourier transform infrared spectroscopy, scanning electron microscopy, X-ray diffraction analysis, water contact angle measurement, tensile strength and melt flow rate measurement. All the results showed that using the ether assisted solid-phase free radical grafting process is an efficient and versatile approach to produce functional polypropylene. [ABSTRACT FROM AUTHOR]

A new strategy for the straightforward alkylation of heteroarenes under mild conditions was developed. It employed silver catalyst for the cross dehydrogenative coupling between heteroarenes and cyclic ethers to construct a new C(sp2)−C(sp3) bond. This reaction was carried out in water under room temperature and applicable to various heteroarenes such as pyridines, quinolines and isoquinolines derivatives with good functional group compatibility. [ABSTRACT FROM AUTHOR]

Dry skin is common to many pruritic diseases and is difficult to improve with oral traditional antihistamines. Recently, increasing evidence indicated that histamine H4 receptor (H4R) plays an important role in the occurrence and development of pruritus. Extracellular signal-regulated kinase (ERK) phosphorylation activation in the spinal cord mediates histamine-induced acute and choric itch. However, whether the histamine H4 receptor regulates ERK activation in the dry skin itch remains unclear. In the study, we explore the role of the histamine H4 receptor and p-ERK in the spinal cord in a dry skin mouse model induced by acetone-ether-water (AEW). q-PCR, Western blot, pharmacology and immunofluorescence  were applied in the study. We established a dry skin itch model by repeated application of AEW on the nape of neck in mice. The AEW mice showed typically dry skin histological change and persistent spontaneous scratching behaviour. Histamine H4 receptor, instead of histamine H1 receptor, mediated spontaneous scratching behaviour in AEW mice. Moreover, c-Fos and p-ERK expression in the spinal cord neurons were increased and co-labelled with GRPR-positive neurons in AEW mice. Furthermore, H4R agonist 4-methyhistamine dihydrochloride (4-MH)induced itch. Both 4-MH-induced itch and the spontaneous itch in AEW mice were blocked by p-ERK inhibitor U0126. Finally, intrathecal H4R receptor antagonist JNJ7777120 inhibited spinal p-ERK expression in AEW mice. Our results indicated that spinal H4R mediates itch via ERK activation in the AEW-induced dry skin mice., (© 2024 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

The study was performed in two phases. First, the polymerization was carried out upon three magnetized surfaces of silica aerogel, zeolite Y, and MIL-101(Cr). Then, optimal molecularly imprinted polymer and optimal extraction conditions were determined by the central composite design-response surface method. Subsequently, the validation parameters of dispersive solid-phase extraction based optimal molecularly imprinted polymer were examined for the extraction of the fuel ether oxygenates. The optimal conditions include the type of adsorbent: Zeolite-magnetic molecularly imprinted polymer, the amount of adsorbent: 40 mg, pH: 7.7, and absorption time: 24.8 min which was selected with desirability equal to 0.996. The calibration graphs were linear between 1 and 100 μg L -1 , with good correlation coefficients. The limits of detection were found to be 0.64, 0. 4, and 0.34 μg L -1 for methyl tert-butyl ether, ethyl tert-butyl ether, and tert butyl formate, respectively. The method proved reliable for analyzing fuel ether oxygenates in drinking water., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

In this paper, we investigate the role of Bitcoin as a safe haven against the stock market losses during the spread of COVID-19. The performed analysis was based on a regression model with dummy variables defined around some crucial dates of the pandemic and on the dynamic conditional correlations. To try to model the real dynamics of the markets, we studied the safe-haven properties of Bitcoin against thirteen of the major stock market indexes losses using daily data spanning from 1 July 2019 until 20 February 2021. A similar analysis was also performed for Ether. Results show that this pandemic impacts on the Bitcoin status as safe haven, but we are still far from being able to define Bitcoin as a safe haven.

With the aim to prepare asymmetric acetylenic γ-glycols, the reactions of 1-(2-ethoxyethyl)piperidin-4-one with propargyl alcohol were studied and the reaction conditions were optimized to reach satisfactory yields of the target glycols. Some transformations of the γ-glycols were studied. It was found that the reaction of 1-(2-ethoxyethyl)-4-(3-hydroxyprop-1-yn-1-yl)piperidin-4-ol with ethyl bromide involves exclusively the OH group on the quaternary carbon atom to form a monoethyl ether, and the mercury-catalyzed hydration involves cyclization with the elimination of a water molecule from the keto glycol moiety, leading to a spiroketone. It was shown that the catalytic reduction of 1-(2-ethoxyethyl)-4-[2-(1-hydroxycyclohexyl)ethynyl]piperidin-4-ol at atmospheric pressure produces a mixture of a saturated and an unsaturated products in a 1 : 2 ratio. Quantum-chemical calculations of the stable conformers of the synthesized asymmetric acetylenic γ-glycols were performed by the RHF/STO-3G method with geometry optimization using Gaussian 09 software. [ABSTRACT FROM AUTHOR]

The article presents discovery of chloroform and anaesthetic drugs that preceded its use or followed it as well as notable names connected with this history. Part one deals with the three oldest agents: ether, nitrous oxide and chloroform. [ABSTRACT FROM AUTHOR]

This study sets out to determine the extent to which socalled "artificial Edens" were present in the literary works of Joaquín Dicenta and how they manifested in the bohemian life attributed to this author. One of the key pieces when analysing this question will be El Crimen de Ayer (1908), in which the author recreates the bohemian lifestyle of French literato Henry Murger, adapting it to the modern vices of his contemporary age. A modernity in which ether was quaffed in elegant cosmopolitan cocktails, and opium was carried in little glass phials. All these scenes are portrayed in Dicenta's novel, who also refers, in other works, to the effects of consuming ether and opium in men and women. Furthermore, this paper seeks to ascertain the extent to which Joaquín Dicenta was in tune with that modernity when he talks about these drugs. [ABSTRACT FROM AUTHOR]

The research employs WLS Regression for examining the main determinants of the ICO profitability in the crowdfunding stage. The variables are divided into three main categories: financial and technological aspects, and the ICO characteristics, with the aim of verifying which parts most influence the funds raised. The results imply that financial and technological aspects might indeed have an impact on the ICO profitability. The key factors covered are the opensource code availability and the preset hard cap. Overall, the econometric analysis discloses that the amount raised during the ICO is not affected by the availability of a white paper and pre-sales, even though some researchers argue differently. [ABSTRACT FROM AUTHOR]

Background/aim of the study: The objective of the present study is to investigate the evolution of surgery in the 19th century in Greece. Material and methods: Medline and books on the subject were searched as well as 19th-century medical journals and books on surgery, and the Proceedings of the Medical Society of Athens (IEA) from 1835 to 1900. Results: Existential doctors treated patients and injured at the beginning of the 19th century and during the Greek revolution. The first political hospital, the "Municipal Hospital of Athens", started operating in 1842. The pain was abolished in the operating room due to the administration of ether in 1846 by W. Morton. Six months later, E. Treiber and N. Petsalis administered ether anesthesia for the first time in Greece. In February 1848, at the meeting of the Medical Society of Athens, V. Rezer and I. Olympios mentioned the first chloroform anesthesia. Despite these achievements, anesthesia was marginalized, and the number of surgical operations performed was negligible. When the experience was gained, and antiseptic was introduced into clinical practice, surgery was gradually extended to more serious and heavier surgeries in the 1880s and 90s, which laid the foundations for modern surgery. Conclusions: Although essential changes were made for surgery in the 19th century in Greece, the number of surgeries being performed remained small for a while. After the accumulation of experience of anesthesia with ether or chloroform and the introduction of antiseptic in the clinical practice, surgery thrived in the 1880s and 90s. [ABSTRACT FROM AUTHOR]

We apply a vector autoregression (VAR) model to investigate the market cycles of Initial Coin Offerings (ICOs) as well as their relationships with bitcoin and ether. Our sample covers 104 weekly observations between January 2017 and December 2018. Our results show that ICO market cycles exist and that shocks to the growth rates of ICO volumes are persistent. In addition, shocks in cryptocurrency returns have a substantial and positive effect on ICO volumes. In contrast, the volatility of cryptocurrency returns does not significantly affect ICO volumes. Our results are robust to using (i) the number of successfully completed ICO campaigns instead of ICO volumes and (ii) ICO data from a different data source. Our study has implications for financial practice, in particular for cryptocurrency investors and entrepreneurial firms conducting ICOs. [ABSTRACT FROM AUTHOR]

High‐performance Na‐ion capacitor (NIC) was constructed with graphite recovered from spent Li‐ion batteries (LIBs) as battery‐type negative electrode and high‐surface‐area activated carbon as a supercapacitor component. Unlike Li‐insertion into graphite, Na‐insertion into graphite is extremely limited; hence, a "solvent‐co‐intercalation" mechanism was proposed for high reversibility using ether family solvents. First, the Na‐insertion properties were assessed in the half‐cell assembly with 0.5 m NaPF6 in tetraethylene glycol dimethyl ether as an electrolyte solution and compared with the commercial graphite. The NIC comprised pre‐sodiated graphite as a negative electrode and commercial activated carbon as a cathode. This fascinating NIC configuration displayed the maximum energy density of 59.93 Wh kg−1 with exceptional cyclability of 5000 cycles at ambient temperature with approximately 98 % retention. Interestingly, the electrode aging process in the presence of electrolyte resulted in approximately 19 % higher energy density than the routine electrode heat treatment. Further, the electrochemical activity of the NIC at various temperatures was studied, and it was found that the graphite recovered from spent LIBs could be effectively reused towards the construction of high‐performance charge storage devices with exceptional performance. [ABSTRACT FROM AUTHOR]

Lignin may serve as a renewable feedstock for the production of chemicals and fuels if mild, scalable processes for its depolymerization can be devised. The use of small organic thiols represents a bioinspired strategy to cleave the β‐O‐4 bond, the most common linkage in lignin. In the present study, synthetic β‐O‐4 linked polymers were treated with organic thiols, yielding up to 90 % cleaved monomer products. Lignin extracted from poplar was also treated with organic thiols resulting in molecular weight reductions as high as 65 % (Mn) in oxidized lignin. Thiol‐based cleavage of other lignin linkages was also explored in small‐molecule model systems to uncover additional potential pathways by which thiols might depolymerize lignin. The success of thiol‐mediated cleavage on model dimers, polymers, and biomass‐derived lignin illustrates the potential utility of small redox‐active molecules to penetrate complex polymer matrices for depolymerization and subsequent valorization of lignin into fuels and chemicals. [ABSTRACT FROM AUTHOR]

This essay argues that the Duineser Elegien articulate Rilke's conception of air as a material expression of space. The Elegies present spaces pervaded by aerial substances such as breath, wind and ether; thereby, they transform space from a passive background or a mere void into an entity that can be perceived in its own right. I show that the Elegies' recasting of vacuity into filled space engages the scientific rethinking of space and matter in the period, in particular, the idea of the ether in physics and the discourse of milieu in biology. When, in his Rodin texts, Rilke argues that sculptures engender their own 'Umgebung' and 'Milieu', he harnesses the biological idea of environment for aesthetic objects. Taking a cue from Rodin's statues, which transform the empty spaces around themselves into atmospheric envelopes, the Elegies evoke spaces as instances of hollowness that revert into fullness. This ability of space to change from a negation into a determination makes it into an ideal poetic medium for Rilke who wants to show the reversibility of lament into affirmation. [ABSTRACT FROM AUTHOR]

Methyl eugenol is a naturally occurring substance found in the essential oils of several plant species. It is a cheap and abundant material with a rather limited interest as perfuming ingredient. This research investigated the structure-odour relationship of methyl eugenol and its derivatives, focusing on the chemical transformation of the double bond to hydroxyether derivatives in a controlled manner. Two derivatives 2-(4-ethyl-3-methoxybenzyl)oxirane (68.8% yield) and 1-(3,4-dimethoxyphenyl)-3-ethoxypropan-2-ol (63.58% yield), were synthesized from methyl eugenol. This research found that the odour characteristic of 2-(4-ethyl-3-methoxybenzyl)oxirane[floral, fresh, slight lime and sweet]compounds, is clearly different from the odours of the 1-(3,4-dimethoxyphenyl)-3-ethoxypropan-2-ol [Glue-like, pungent, and Caramel-like]. It is evident from our observations that double bond substitution and functional alteration of the methyl eugenol modifies the perceived odour of methyl eugenol derivative. Thus, structural modification overall led to an increase in odour potency. [ABSTRACT FROM AUTHOR]