Efecto de extracto de orégano sobre características fisicoquímicas y estructurales de un gel cárnico a base de calamar gigante durante su vida útil

Tesis de Maestría en Ciencias QuímicasEl calamar gigante (Dosidicus gigas) es un molusco de importancia económica en México, el 80% de esta especie se considera comestible, a pesar de que es una especie con alto contenido proteico (~18%) y bajo contenido de colesterol, la alta actividad enzimática que posee (enzimas endógenas y microbianas) genera una degradación proteica y por consecuencia, un descenso en las propiedades funcionales desde el punto de vista estructural. El objetivo del presente trabajo fue el desarrollo de un gel cárnico a base de esta especie y evaluar el efecto de la aplicación de un extracto acuoso de orégano durante el almacenamiento en refrigeración. Se evaluaron 4 métodos de extracción proteica; el proceso denominado B presentó las características apropiadas para el desarrollo del gel. Se adicionó el extracto de orégano (obtenido empleando una relación orégano-agua 1:15 y un tiempo de agitación de 15 min a 20°C) en un 5% v/v respecto a la disolución proteica a gelificar. La adición del extracto disminuyó la producción de bases volátiles y trimetilamina durante el almacenamiento. En cuanto al desarrollo microbiológico, existe una diferencia de 0.4 unidades logarítmicas en cuanto al conteo de mesófilos aerobios y de 2.7 unidades logarítmicas en el conteo de coliformes totales, ambas a favor de la muestra con extracto. Respecto a las características estructurales, no existe diferencia significativa entre las muestras, con y sin extracto, en el parámetro de dureza al final del almacenamiento. La adición de extracto acuoso de orégano permitió mantener las características fisicoquímicas y microbiológicas del gel durante el periodo de almacenamiento.Conacy

Gauge field theory approach to spin transport in a 2D electron gas

We discuss the Pauli Hamiltonian including the spin-orbit interaction within an U(1) x SU(2) gauge theory interpretation, where the gauge symmetry appears to be broken. This interpretation offers new insight into the problem of spin currents in the condensed matter environment, and can be extended to Rashba and Dresselhaus spin-orbit interactions. We present a few outcomes of the present formulation: i) it automatically leads to zero spin conductivity, in contrast to predictions of Gauge symmetric treatments, ii) a topological quantization condition leading to voltage quantization follows, and iii) spin interferometers can be conceived in which, starting from a arbitrary incoming unpolarized spinor, it is always possible to construct a perfect spin filtering condition.Comment: Invited contribution to Statphys conference, June 2009, Lviv (Ukraine

The document/book as a form of curatorial creativity

This thesis discusses the document/book as an act of recording that can serve as a form for curatorial creativity. Firstly, it explores the document as a space in a hybrid analog and digital era. Then, it introduces concrete examples of how curating the gallery and the book has changed in the 20th and 21st centuries. It follows a critical analysis of society as one big accumulation of documents. It proposes the invention of writing as the base of our current digital spaces and the space of the book as architecture. In respect to the curatorial discourse, it focuses on Springer's proposition of engaging with the library in order to develop new ways of organizing, collecting, and reassembling information. The first chapter introduces Benjamin Bratton's diagram of "The Stack", which serves to explore the physical spaces of information, describing how the infrastructure of books has come to expand significantly from clay to paper, and now to the Cloud. It proposes the codex-book, a stack of paper sheets as an analogy of the stack through the example of artist Irfan Hendrian "Some Other Matter" exhibition. It also proposes the page—a place of inventory and invention— as the first virtual space of humanity. The second chapter discusses the library's primary functions of storage and retrievability —proposing the Library of Alexandria as the first information organization. Then comes back to an example of how the old model of the library can be used for creating a new display for the gallery as well as giving value to its collection through physical activation. Finally, it explores some of the invisible systems (covers, algorithms, tags) that are now building our digital libraries. The third chapter focuses on copy and print as essential tools for recording, preservation, and building collections. It introduces the history of mass digitization and the changes it has brought to analog documents. It also explores the space of digital and print through Kenneth Goldsmith's curatorial project that called out to print out all the internet. This example leads us to discuss the history of the A4-size paper sheet as the first completely standardize product. The fourth chapter presents the "neutral" containers —starting from the concept of the "gallery-book" proposed by Bernard Teyssendier as a place of movement, pleasure, and learning. It also explores architecture and design as curatorial infrastructure for exhibitions happening both in a gallery space and on a blank document. Finally, it creates a parallel between the white paper page and the white gallery wall as places of artistic intervention, which far from being invisible follow specific predefined structures. The fifth chapter focuses on presenting projects that propose new curated writing and reading contexts between the print and digital. Here, Brian O'Doherty's issue for "Aspen" magazine is proposed as proto-hypertext or as a premonition of the website. Then, the website-as-gallery concept is explored through the example of Kadist's "One Sentence Exhibition" project. This example leads to exploring the fragility and impermanence of the hyperlink, in contrast to its printed counterparts. The final chapter presents three projects that use the infrastructure of the book and the library as a curatorial agency —proposing new methods for curating information through collection, organization, and research. "Intercalations", a paginated exhibition series by Anna-Sophie Springer and Etienne Turpin; "MAP", a folded encyclopedia by the David A. Garcia architecture studio; and "Carte(s) Mémoire(s)" by ExposerPublier that proposes the exhibition as a moment of activation

O&M Models for Ocean Energy Converters: Calibrating through Real Sea Data

Of the cost centres that combine to result in Levelised Cost of Energy (LCOE), O&M costs play a significant part. Several developers have calculated component costs, demonstrating how they can become commercially competitive with other forms of renewable energy. However, there are uncertainties relating to the O&M figures that can only be reduced through lessons learned at sea. This work presents an O&M model calibrated with data from real sea experience of a wave energy device deployed at the Biscay Marine energy Platform (BiMEP): the OPERA O&M Model. Two additional case studies, utilising two other O&M calculation methodologies, are presented for comparison with the OPERA O&M Model. The second case study assumes the inexistence of an O&M model, utilising a Simplified Approach. The third case study applies DTOcean’s (a design tool for ocean energy arrays) O&M module. The results illustrate the potential advantages of utilising real sea data for the calibration and development of an O&M model. The Simplified Approach was observed to overestimate LCOE when compared to the OPERA O&M Model. This work also shows that O&M models can be used for the definition of optimal maintenance plans to assist with OPEX reduction.The authors are grateful to the European commission for funding the OPERA and EnFAIT projects as part of the Horizon 2020 framework. The authors also thankful to Oceantec-Idom for providing feedback to OPERA model’s inputs. A special thanks to Shona Pennock and Donald Noble for their diligent proofreading of this paper

Activity Recognition for IoT Devices Using Fuzzy Spatio-Temporal Features as Environmental Sensor Fusion

The IoT describes a development field where new approaches and trends are in constant change. In this scenario, new devices and sensors are offering higher precision in everyday life in an increasingly less invasive way. In this work, we propose the use of spatial-temporal features by means of fuzzy logic as a general descriptor for heterogeneous sensors. This fuzzy sensor representation is highly efficient and enables devices with low computing power to develop learning and evaluation tasks in activity recognition using light and efficient classifiers. To show the methodology's potential in real applications, we deploy an intelligent environment where new UWB location devices, inertial objects, wearable devices, and binary sensors are connected with each other and describe daily human activities. We then apply the proposed fuzzy logic-based methodology to obtain spatial-temporal features to fuse the data from the heterogeneous sensor devices. A case study developed in the UJAmISmart Lab of the University of Jaen (Jaen, Spain) shows the encouraging performance of the methodology when recognizing the activity of an inhabitant using efficient classifiers

The enzymatic determination of glucose in carbonated beverages: a useful tool for the undergraduate students to learn the basis of enzymatic analysis and the comparison of two analytical methods

The importance of enzymatic analysis in biochemistry, clinical chemistry and food chemistry is undoubted. The course "Applied Biochemistry" in our Faculty is aimed to undergraduate students of Chemistry and Biochemistry. In this subject, the principles and applications of enzymatic analysis are presented to the students, who receive a theoretical introductory lecture in the classroom before they carry out an experiment that should be feasible to be solved in a short laboratory period. The experimental protocol here presented, based on the enzymatic determination of glucose in carbonated beverages, has been implemented at the University of Málaga and it has been optimized according to the students’ results and commentaries along the last years. It aims to illustrate basic issues relating enzymatic analysis, including its potential application to food chemistry. Although there are several enzymatic methods that can be used for the determination of glucose, we selected the one based on the coupled reactions of glucose oxidase (GOD; EC 1.1.3.4.) and peroxidase (POD; EC 1.11.1.7.) because the kinetic constants of glucose oxidase allow the mentioned enzymatic reactions to be used in both, the end point and the kinetic enzymatic analysis methods. In this way, data for two different protocols for the determination of glucose concentration are obtained by the students from a single reaction mixture. Students construct a calibration curve for each method using a glucose standard solution, and use them to determine the glucose concentration in the problem solutions. The inclusion of replicate samples in the determination of the glucose concentration of an “ideal problem” (glucose in purified water) is used to illustrate the principles of statistics in the lab, and comparison with the “real value” allows an estimation of the accuracy of each method. The evaluation of glucose concentration in four carbonated beverages: coloured coke and uncoloured tonic sodas (regular or sugarless in both cases) makes student to recognise the appearance of interferences that should be either avoided or eliminated. Since all samples are analysed by means of end-point and kinetic methods, students can discuss the applicability of each method to these specific analytical problems. They are also encouraged to compare both analytical methods in terms of sensitivity, selectivity, accuracy, and time consumed. Chemistry and Biochemistry undergraduate students having performed this experiment in our laboratories have found it formative, interesting and challenging.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

A practice project to prevent the cookbook model as modus operandi for biochemistry laboratory learning

Laboratory learning is a crucial component of chemistry and biochemistry instruction and should be conceived as a way to develop students’ reasoning, technical or practical skills, introducing them into the scientific method principles. Nevertheless, the heavily criticized “expository instruction style”, characterized by a cookbook nature, is still the most widespread style of laboratory instruction in our universities. Alternative learning styles based in the inquiry, discovery and problem-based pedagogical approaches, have been reported to promote students’ problem solving skills, critical thought and self-confidence development. We are currently involved in the Educative Innovation Project PIE17-065, funded by University of Malaga, aimed to improve the teaching practice of Biochemistry laboratory to undergraduate students. Based on an enzymatic analysis of glucose in soft-drinks we have developed a laboratory protocol as a part of a full practice project where students must work before and after the lab session, in order to prevent the cookbook model as modus operandi, therefore preventing the situation where the students get a first glimpse of the experiment protocol whereas they put on their lab coat. The learning activities have been designed to move our students from the passive role that characterizes the step-by-step procedures, to an active and critical attitude that starts before and remains after their laboratory session, also minimizing time, space, and equipment resources. Our results have shown that this experiment has improved the learning of both, future biochemists and chemists, which showed a very positive perception of the whole practical project.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech. PIE 17-06

Analytical and numerical simulations of an Oscillating Water Column with humidity in the air chamber

This paper examines an Oscillating Water Column (OWC) model, where the air chamber is represented as a dry air–water vapour mixture, based on the thermodynamics of a real gas. The novelty of this study consists of the inclusion of humidity effects on the general performance of the OWC and its coupling with the radiation–diffraction problem of the device. Using FLUENT®, a numerical 2D flume is built to simulate wave–induced flow in the OWC. Air phase properties are adjusted to represent the presence of moisture. Turbine linear performance, according to a standard Wells turbine power take–off system, is simulated by means of an Actuator Disk Model (ADM). Numerical outputs are compared with analytical solutions of the classic OWC radiation–diffraction problem, in which the theoretical real gas model is embedded. Results show that the use of real gas thermodynamic theory reduces considerably the predicted power output of OWC devices, with theoretical losses reaching 50% in certain cases. The effect of humidity mitigates resonant conditions. Techno–economic considerations justify the inclusion of real gas theory to achieve competitive devices

El autoconcepto en hombres y mujeres mexicanos

The aim of the present research is to know the characteristics of the self-concept, which prevail in Mexican men and women of different ages. It was used the self-concept questionnaire (Valdez-Medina, 1994), with validity for Mexican samples, and the study was carried out with a sample of 600 subjects distributed in six groups, according to their ages and sex. The result shows that Mexican women, except those with a college level, still see themselves as sentimental, affectionate, warm, romantic, and not as smart as men. These characteristics, besides clearly showing the sensibility, tenderness, love and peace Mexican women have, denote some socially worthwhile features in Mexican culture. Mexican women are seen as expressive, while, on the other hand, men are seen as instrumental