Determinants and consequences of internal and international migration

This paper analyzes the current migration in rural population in the south of Veracruz state (Mexico). We identify three different spaces of migration, traditional markets, the northern border and the United States. Applying a multinomial logistic model and taking into account individual, family, and local characteristics of the migrants, we find different determinants in each space. These determinants are related to the objectives, needs and means of the migrants and their families. Otherwise, each space involves different consequences to the family in terms of the relationships between migrants and the rest of their relatives.consequences, determinants, family, intergenerational relations, internal migration, international migration, Mexico, migration, reproduction, rural population

Two-dimensional Quasi-bessel beam synthesis and frequency-scanning leaky-wave launchers

In this paper, a technique to synthesize a 2D frequency-scanned high order Bessel beam in a parallel plates waveguide (PPW) scenario is presented. This technique is based on a one dimensional beam launcher, rather than the more typical axicons or the more recent metasurfaces and antenna arrays for 3D Bessel beam synthesis. With this launcher, it is possible to generate a 2D Bessel beams whose direction can be controlled by changing the frequency of the feeding signal in the Ku band from 14.5 GHz to 15 GHz. It is demonstrated how this can be done by combination of two leaky waves (LW), which can be created by the same 1D structure, scanning at different angles and launched to the PPW region. The beams are generated in a triangular area, with one of its sides being the launcher itself and the other sides are defined by the direction of radiation of each of the forming leaky wave

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

Long-term static and dynamic monitoring to failure scenarios assessment in steel truss railway bridges: A case study

The latest studies on failures in steel truss-type bridge found that they are highly vulnerable to damage and thus prone to potential local or total collapse. Many authors recommend monitoring the critical elements in the existing steel truss-type bridges in real time to anticipate any failures in local members. Although mechanical strain is the most frequently used variable for this purpose, this method also happens to be the most expensive monitoring strategy. This paper describes a case study of failure scenarios assessment in a steel truss-type railway bridge after extensive long-term monitoring conducted by the authors, based on measuring vertical deflections and modal frequencies. The structure has both an isostatic and a hyperstatic configuration, and was assessed by means of a combination of: (i) long-term monitoring results, and (ii) a finite element analysis to simulate several failure scenarios. A sensitivity study of the different failure scenarios has been carried out, identifying those that can be detected. The results are used to define practical recommendations for failure detection by measuring vertical deflections and modal frequencies

Management Indicators for the Organisational Sustainability of Associative Productive Ventures

[EN] Associative enterprises linked to the social economy continue to be an important economic alternative for small producers, generating decent work opportunities for people excluded from the formal labour market and contributing to sustainable development. The social and economic importance of this type of initiative has prompted several scientific publications on its success factors, leaving a gap in its practicality, raising the question: How can success factors of associative productive ventures be integrated into management indicators that promote their organisational sustainability? The aim is to define and prioritise management indicators that promote associative productive ventures through the analysis of key success factors. This study was carried out using a combination of BSC management methodology and AHP multicriteria decision making, based on a bibliographic review of success factors and the criteria of experts including managers of consolidated production associations in Quito-Ecuador. The results show that the indicators of participatory leadership, technical training and labour integration are the most relevant in the consolidation of associative productive ventures, prompting the conclusion that the prioritisation and integration of business and social management indicators would boost the organisational sustainability of associative ventures.This research was funded by Central University of Ecuador, grant number R-006-2019.Guananga, LA.; Poveda Bautista, R.; García-Melón, M. (2023). Management Indicators for the Organisational Sustainability of Associative Productive Ventures. Sustainability. 15(23). https://doi.org/10.3390/su152316166152

Treatment adherence and other patient-reported outcomes as cost determinants in multiple sclerosis: a review of the literature

Background: Treatment adherence is one of the key factors for achieving optimal clinical outcomes. In order to assess costs related to adherence to, and persistence and compliance with, disease-modifying therapies (DMTs) in patients with multiple sclerosis (MS), a narrative review of the literature was performed. Satisfaction with and preference for DMTs and their delivery devices were also assessed, as both can have an influence on patients’ adherence and persistence. Methods: Electronic databases (MEDLINE, PubMed, Google Scholar, congress proceedings) were searched to identify publications analyzing MS costs related to adherence, persistence, satisfaction, and preferences for MS treatments. Bibliographic references were hand searched. English or Spanish studies published between January 2007 and January 2013 were selected. Results: A total of 398 titles were identified, of which 12 met the inclusion criteria. Six studies evaluated the impact of adherence, persistence, and compliance on treatment costs; four publications analyzed satisfaction with DMTs; and two assessed treatment preferences based on attributes of the delivery device. Increased adherence and persistence were associated with better clinical outcomes, leading to lower relapse risk (odds ratio [OR]: 0.71; 95% confidence interval [CI]: 0.59–0.85) and a decrease in health care resource use, such as MS-related hospitalizations (OR: 0.63; 95% CI: 0.47–0.83) and emergency department visits (OR: 0.80; 95% CI: 0.60–1.07). This reduction in resource use led to a patient/year total cost reduction (excluding DMT costs) of up to 22%. Conclusion: This review highlights the importance of ensuring adequate adherence in MS patients through treatments and devices better tailored to patients’ needs that could enhance clinical outcomes and reduce MS costs. Understanding the factors underlying satisfaction and compliance with treatment and patients’ preference for certain therapies could help in the development of strategies that can improve adherence