Secundo y la gran laguna en el Dialogus de oratoribus

[email protected] artículo examina un problema puntual en el polémico Dialogus de oratoribus: la cuestión de la gran laguna entre los capítulos 35 y 36. El autor del estudio expone una perspectiva histórica de los principales argumentos esgrimidos por la investigación sobre este asunto a lo largo, especialmente, del siglo XX. Para determinar la extensión y el contenido de la parte perdida, el análisis se estructura en torno a dos ejes: 1) la tradición manuscrita; y 2) la comparación entre el opúsculo y otros diálogos.The paper examines a specific problem in the controversial Dialogus de oratoribus: the issue of the great lacuna between chapters 35 and 36. The author of the article places in historical perspective the most important arguments uncovered by investigations in this area, especially those of the twentieth century. In order to determine the size and content of the missing part, the analysis is organized around two central points: 1) the manuscript tradition, and 2) the comparison between the book and other dialogues

Digital Electrical Substation Communications based on Deterministic Time-Sensitive Networking over Ethernet

The authors would like to thank Alberto Sánchez Pérez and Grupo Cuerva S.L. for their assistance in the realization of the field tests at their electrical substation facility in Escúzar (Granada, Spain); and Jesús Torres Tenor and the CIRCE Foundation for their contribution to the development of a substation GOOSE traffic generator.This work presents a novel use case with Time-Sensitive Networks (TSN) for implementing a deterministic system allowing the joint transmission of all substation communications over the same Ethernet-based infrastructure. This approach streamlines the transition to Smart Grid by simplifying the typically complex architecture of electrical substations, characterized by multiple field buses and bridging devices. Thus, Smart Grid represents a disruptive innovation advancing substations to an “all-digital” environment with a uniform interface to access, manage, and update their communications and variables. TSN can serve as its underlying foundation as it is based on open, interoperable standards and enhancements for Ethernet that can establish deterministic communications with bounded end-to-end latency. This is shown with a TSN Proof of Concept (PoC) in a real-life substation that can integrate its most usual signals: digitized analog triggers for critical events or interlocks, GOOSE signaling (IEC 61850), and Best-Effort “Internet-like” traffic. This TSN PoC is shown to be versatile enough to propagate digitized critical events around 160 µs earlier than legacy substation equipment while preserving the integrity of background traffic. Furthermore, its flexibility was characterized in-depth in controlled laboratory tests, thereby confirming TSN as a viable alternative for supporting Smart Grid so long as the appropriate configuration is supplied.Amiga-7 Project RTI2018-096228-B-C3FITOPTIVIS Project H2020-RIA ECSEL-JU-2017-783162Spanish Ministerio de Economia y Transformacion Digital (MINECO) APCIN PCI2018-093184German Research Foundation (DFG

On Teaching Sallust in Latin: The Why and the How

There exist many pedagogical methods we can use to examine, expound and explain ancient authors to our students. In this paper I propose an alternative approach to teach Sallust in an undergraduate setting, with explanatory aids, exercises, tests and quizzes. The latter result not from quick consideration, but from daily use and application in my own classes. In addition, I give reasons why it is helpful to teach Latin in Latin and what advantages it has for students who have learned well the grammar and have moved on to reading and analysis of the ancient texts. Students who had had no prior exposure to this approach completed an evaluation at the end of the academic year; the results are provided as a conclusion to the article

Development of electrochemical methods for determination of tramadol - analytical application to pharmaceutical dosage forms

A square-wave voltammetric (SWV) method and a flow injection analysis system with amperometric detection were developed for the determination of tramadol hydrochloride. The SWV method enables the determination of tramadol over the concentration range of 15-75 µM with a detection limit of 2.2 µM. Tramadol could be determined in concentrations between 9 and 50 µM at a sampling rate of 90 h-1, with a detection limit of 1.7 µM using the flow injection system. The electrochemical methods developed were successfully applied to the determination of tramadol in pharmaceutical dosage forms, without any pre-treatment of the samples. Recovery trials were performed to assess the accuracy of the results; the values were between 97 and 102% for both methods

Host-Guest interaction between herbicide oxadiargyl and hydroxypropyl-β-cyclodextrin

In the face of a growing human population and increased urbanization, the demand for pesticides will simply rise. Farmers must escalate yields on increasingly fewer farm acres. However, the risks of pesticides, whether real or perceived, may force changes in the way these chemicals are used. Scientists are working toward pest control plans that are environmentally sound, effective, and profitable. In this context the development of new pesticide formulations which may improve application effectiveness, safety, handling, and storage can be pointed out as a solution. As a contribution to the area, the microencapsulation of the herbicide oxadiargyl (OXA) in (2-hydroxypropyl)-β-cyclodextrin (HP-β-CD) was performed. The study was conducted in different aqueous media (ultrapure water and in different pH buffer solutions). In all cases an increment of the oxadiargyl solubility as a function of the HP-β-CD concentration that has been related to the formation of an inclusion complex was verified. UV-Vis and NMR experiments allowed concluding that the stoichiometry of the OXA/HP-β-CD complex formed is 1 : 1. The gathered results can be regarded as an important step for its removal from industrial effluents and/or to increase the stabilizing action, encapsulation, and adsorption in water treatment plants

Microencapsulation of herbicide MCPA with native β-cyclodextrin and its methyl and hydroxypropyl derivatives : an experimental and theoretical investigation

When a pesticide is released into the environment, most of it is lost before it reaches its target. An effective way to reduce environmental losses of pesticides is by using controlled release technology. Microencapsulation becomes a promising technique for the production of controlled release agricultural formulations. In this work, the microencapsulation of chlorophenoxy herbicide MCPA with native β-cyclodextrin and its methyl and hydroxypropyl derivatives was investigated. The phase solubility study showed that both native and β-CD derivatives increased the water solubility of the herbicide and inclusion complexes are formed in a stoichiometric ratio of 1:1. The stability constants describing the extent of formation of the complexes have been determined by phase solubility studies. 1H NMR experiments were also accomplished for the prepared solid systems and the data gathered confirm the formation of the inclusion complexes. 1H NMR data obtained for the MCPA/CDs complexes disclosed noticeable proton shift displacements for OCH2 group and H6 aromatic proton of MCPA provided clear evidence of inclusion complexation process, suggesting that the phenyl moiety of the herbicide was included in the hydrophobic cavity of CDs. Free energy molecular mechanics calculations confirm all these findings. The gathered results can be regarded as an essential step to the development of controlled release agricultural formulations containing herbicide MCPA.Fundação para a Ciência e a Tecnologia (FCT

Voltammetric quantification of fluoxetine: application to quality control and quality assurance processes

The oxidative behaviour of fluoxetine was studied at a glassy carbon electrode in various buffer systems and at different pH using cyclic, differential pulse and square wave voltammetry. A new square wave voltammetric method suitable for the quality control of fluoxetine in commercial formulations has been developed using a borate pH 9 buffer solution as supporting electrolyte. Under optimized conditions, a linear response was obtained in the range 10 to 16 μM with a detection limit of 1.0 μM. Validation parameters such as sensitivity, precision and accuracy were evaluated. The proposed method was successfully applied to the determination of fluoxetine in pharmaceutical formulations. The results were statistically compared with those obtained by the reference high-performance liquid chromatographic method. No significant differences were found between the methods