17 research outputs found
Managing financial risks while performing international commercial transactions: Intertemporal lessons from Athens in classical times
In this paper, we mainly focus on two institutional aspects that are related to financial risk, that is, profiteering and the use of non-fraudulent coins when performing financial transactions. We argue that these two prerequisites were important for the success of the commercially oriented economy of the Athenian state in comparison with its allies in the East Mediterranean during the classical period. In particular, we briefly explain the structure of the Athenian economy, and then we focus on the agoranomoi and the dokimastai, the two main financial institutions related to (i) measures against profiteering and (ii) ensuring the purity of the currency when performing commercial transactions. Then, following a game theoretical approach, we provide a fictional example as to how the two institutions functioned in practice. Our findings confirm that these institutions were crucial in reducing financial risk when performing international commercial transactions, since they provided symmetrical information on the quality and purity of the currencies circulating in the Athenian economy. In the case of the Athenian state, we further convey that measures against profiteering and the use of unadulterated currency comprise intertemporal axioms, in the sense that their importance is not merely a phenomenon of modern times, but rather, on the contrary, one that dates back to much earlier times
Bouveret SyndromeāThe Rarest Variant of Gallstone Ileus: A Case Report and Literature Review
We present a case report of a patient with Bouveret syndrome with interesting radiological findings and successful surgical treatment after failure of the endoscopic techniques. The report is followed by a review of the literature regarding the diagnostic means and proper treatment of this rare entity. Bouveret syndrome refers to the condition of gastric outlet obstruction caused by the impaction of a large gallstone into the duodenum after passage through a cholecystoduodenal fistula. Many endoscopic and surgical techniques have been described in the management of this syndrome. This is a case of a 78-year-old patient with severe medical history who presented in bad general condition with an 8-day history of nausea, multiple bilious vomiting episodes, anorexia, discomfort in the right hypochondrium and epigastrium, and fever up to 38,5Ā°C. The diagnosis of Bouveret syndrome was set after performing the proper imaging studies. An initial endoscopic effort to resolve the obstruction was performed without success. Surgical treatment managed to extract the impacted gallstone through an enterotomy after removal into the first part of the jejunum
3D Printed Voltammetric Sensor Modified with an Fe(III)-Cluster for the Enzyme-Free Determination of Glucose in Sweat
In this work, a 3D printed sensor modified with a water-stable complex of Fe(III) basic benzoate is presented for the voltammetric detection of glucose (GLU) in acidic epidermal skin conditions. The GLU sensor was produced by the drop-casting of Fe(III)-cluster ethanolic mixture on the surface of a 3D printed electrode fabricated by a carbon black loaded polylactic acid filament. The oxidation of GLU was electrocatalyzed by Fe(III), which was electrochemically generated in-situ by the Fe(III)-cluster precursor. The GLU determination was carried out by differential pulse voltammetry without the interference from common electroactive metabolites presented in sweat (such as urea, uric acid, and lactic acid), offering a limit of detection of 4.3 Ī¼mol Lā1. The exceptional electrochemical performance of [Fe3O(PhCO2)6(H2O)3]āPhCO2 combined with 3D printing technology forms an innovative and low-cost enzyme-free sensor suitable for noninvasive applications, opening the way for integrated 3D printed wearable biodevices
The role of microRNAs in coronary artery disease: From pathophysiology to diagnosis and treatment
MicroRNAs (miRNAs) are tiny non-coding RNA molecules that regulate gene
expression predominantly at the post-transcriptional level. Far from
being simple intracellular regulators, miRNAs have recently been
involved in intercellular communication and have been shown to circulate
in the bloodstream in stable forms. In the past years specific miRNA
expression patterns have been linked to the development of
atherosclerosis and coronary artery disease, two closely related
conditions. The study of miRNAs has promoted our understanding of the
processes involved in the pathogenesis of atherosclerosis and innovative
diagnostic and therapeutic approaches have emerged. In this review, we
present the role of miRNAs in the development of atherosclerosis, on
coronary artery disease progression and we assess their role as
diagnostic biomarkers. Finally we evaluate the therapeutic and
preventive opportunities that arise from the study of miRNAs in coronary
artery disease and especially in myocardial infarction. (C) 2015
Elsevier Ireland Ltd. All rights reserved
Storage of Methane in Clathrate Hydrates: Monte Carlo Simulations of sI Hydrates and Comparison with Experimental Measurements
Extensive grand canonical
Monte Carlo simulations are performed
for the calculation of the amount of methane gas that can be stored
inside the hydrate structure sI focusing on temperature and pressure
conditions that are of interest to practical applications (e.g., methane
storage/transportation, methane hydrates in nature). Langmuir-type
āabsorption isothermsā are used in order to present
the results for methane in the cages of the hydrate structure. In
particular, the methane content inside the different type of hydrate
cages is given as a function of pressure, where the parameters of
this function are temperature-dependent. A comparison between available
experimental data for cage occupancies and calculated values resulted
in good agreement. The correlation between chemical potential and
pressure is determined through <i>NVT</i> Monte Carlo simulations.
Simulations are performed for the TIP4P/Ice water model and two methane
models (UnitedāAtom and AllāAtom). The calculations
of the current study can be utilized during the process of refining
the estimates of methane gas āin-placeā, in hydrate
deposits, when pressure and temperature conditions at the hydrate
reservoirs are known. A discussion on the implication to geologic
media containing hydrates is also presented
Using clathrate hydrates for gas storage and gas-mixture separations: experimental and computational studies at multiple length scales
<p>Clathrate hydrates have characteristic properties that render them attractive for a number of industrial applications. Of particular interest are the following two cases: (i) the incorporation of large amounts of gas molecules into the solid structure has resulted in considering hydrates as possible material for the storage/transportation of energy or environmental gases, and (ii) the selective incorporation of guest molecules into the solid structure has resulted in considering hydrates for gas-mixture separations. For the proper design of such industrial applications, it is essential to know accurately a number of thermodynamic, structural and transport properties. Such properties can either be measured experimentally or calculated at different scales that span the molecular scale-up to the continuum scale. By using clathrate hydrates as a particular case study, we demonstrate that performing studies at multiple length scales can be utilised in order to obtain properties that are essential to process design.</p