Analysis of the length weight relationships for the Atlantic bluefin tuna, Thunnus thynnus (L.)

The recently adopted models by ICCAT Standing Committee on Research and Statistics (SCRS) for the Atlantic bluefin tuna (ABFT), Thunnus thynnus (L.) (RW= 0.0000159137 SFL^3.020584, WEST; and RW= 0.0000315551 SFL^2.898454, EAST ), together with the models used to date (RW= 0.0000152 SFL^3.0531, for western stock; and RW= 0.000019607 SFL^3.0092, for eastern stock) and an alternative model for the eastern stock (RW= 0.0000188SFL^3.01247), are analyzed in using bi variant samples (SFL (cm), RW (kg)) of 698 pairs of data (K= 2.02 ± 0.23 SD, western stock) and 474 pairs of data (K= 2.03 ± 0.15 SD, eastern stock) with the aim of validating them and establishing which model best fit the reality represented by the samples and, therefore, will have the greatest descriptive and predictive power. The result of the analysis indicates that the adopted models WEST and EAST clearly underestimates the weight of spawning ABFT being the models used to date, as well as the alternative model presented in this paper, that best explains the data of the samples. The result of the classical statistical analysis is confirmed by means of the quantile regression technique, selecting the quantiles 5%, 25%, 50%, 75% and 95%. Other biological and fisheries indicators also conclude that the models WEST and EAST gradually underestimates the weight of ABFT spawners (of 2 3 m) by 8 14%; the average value of K (1.78 and 1.82) obtained for spawners (> 140 cm), using the adopted models, represents ABFT in low fattening condition; and the evolution of K throughout the year, by using the monthly L-W adopted models, does not represent the significant increase in weight that ABFT experiences in nature between August and December.Cort, JL.; Estruch, VD. (2016). Analysis of the length weight relationships for the Atlantic bluefin tuna, Thunnus thynnus (L.). Collective Volume of Scientific Papers. 154:1-38. http://hdl.handle.net/10251/78955S13815

Optimum sample size to estimate mean parasite abundance in fi sh parasite surveys

[EN] To reach ethically and scientifically valid mean abundance values in parasitological and epidemiological studies this paper considers analytic and simulation approaches for sample size determination. The sample size estimation was carried out by applying mathematical formula with predetermined precision level and parameter of the negative binomial distribution estimated from the empirical data. A simulation approach to optimum sample size determination aimed at the estimation of true value of the mean abundance and its confidence interval (CI) was based on the Bag of Little Bootstraps (BLB). The abundance of two species of monogenean parasites Ligophorus cephali and L. mediterraneus from Mugil cephalus across the Azov-Black Seas localities were subjected to the analysis. The dispersion pattern of both helminth species could be characterized as a highly aggregated distribution with the variance being substantially larger than the mean abundance. The holistic approach applied here offers a wide range of appropriate methods in searching for the optimum sample size and the understanding about the expected precision level of the mean. Given the superior performance of the BLB relative to formulae with its few assumptions, the bootstrap procedure is the preferred method. Two important assessments were performed in the present study: i) based on CIs width a reasonable precision level for the mean abundance in parasitological surveys of Ligophorus spp. could be chosen between 0.8 and 0.5 with 1.6 and 1x mean of the CIs width, and ii) the sample size equal 80 or more host individuals allows accurate and precise estimation of mean abundance. Meanwhile for the host sample size in range between 25 and 40 individuals, the median estimates showed minimal bias but the sampling distribution skewed to the low values; a sample size of 10 host individuals yielded to unreliable estimates.SS and VS were supported by MEDEA project fellowships, Erasmus Mundus Action 2. CC-S was funded by project #MTM2014-52975-C2-1-R:" Inference in Structured Additive Regression (STAR) Models with Extensions to Multivariate Responses. Applications in Biomedicine", cofinanced by the Ministry of Economy and Competitiveness (SPAIN) and by the European Regional Development Fund (FEDER). This study is partially supported by Ministry of Education and Science of Ukraine, project #1/17.Shvydka, S.; Sarabeev, V.; Estruch, VD.; Cadarso-Suarez, C. (2018). Optimum sample size to estimate mean parasite abundance in fi sh parasite surveys. Helminthologia. 55(1):52-59. https://doi.org/10.1515/helm-2017-0054S5259551Rohde, K., Hayward, C., & Heap, M. (1995). Aspects of the ecology of metazoan ectoparasites of marine fishes. International Journal for Parasitology, 25(8), 945-970. doi:10.1016/0020-7519(95)00015-tAnderson, R. M., & Gordon, D. M. (1982). Processes influencing the distribution of parasite numbers within host populations with special emphasis on parasite-induced host mortalities. Parasitology, 85(2), 373-398. doi:10.1017/s0031182000055347Poiani, A. (1992). Ectoparasitism as a possible cost of social life: a comparative analysis using Australian passerines (Passeriformes). Oecologia, 92(3), 429-441. doi:10.1007/bf00317470Kleiner, A., Talwalkar, A., Sarkar, P., & Jordan, M. I. (2014). A scalable bootstrap for massive data. Journal of the Royal Statistical Society: Series B (Statistical Methodology), 76(4), 795-816. doi:10.1111/rssb.12050Jovani, R., & Tella, J. L. (2006). Parasite prevalence and sample size: misconceptions and solutions. Trends in Parasitology, 22(5), 214-218. doi:10.1016/j.pt.2006.02.011BAGGE, A. M., SASAL, P., VALTONEN, E. T., & KARVONEN, A. (2005). Infracommunity level aggregation in the monogenean communities of crucian carp (Carassius carassius). Parasitology, 131(3), 367-372. doi:10.1017/s0031182005007626Belghyti, D., Berrada-rkhami, O., Boy, V., Aguesse, P., & Gabrion, C. (1994). Population biology of two helminth parasites of flatfishes from the Atlantic coast of Morocco. Journal of Fish Biology, 44(6), 1005-1021. doi:10.1111/j.1095-8649.1994.tb01272.xTAYLOR, L. R. (1961). Aggregation, Variance and the Mean. Nature, 189(4766), 732-735. doi:10.1038/189732a

Reforzar la enseñanza de las matemáticas desde el primer curso de grado con proyectos

[EN] The way to build mathematical knowledge of a scientist / engineer differs from that corresponding to the student who accesses a degree in mathematics or other sciences. Learning based on the process of establishing, analyze and validate mathematical models allows the effective acquisition of math skills. In addition, activities based on mathematical modeling can be motivating elements in the teaching / learning process, arousing student interest to cognitive basis on which fundamental mathematical concepts are developed in the mathematical training of future scientist or engineer.[ES] La manera de construir el conocimiento matemático de un científico/ingeniero difiere de la que corresponde al estudiante que accede a un grado en matemáticas o en otras ciencias. El aprendizaje en base al proceso de establecer, analizar y validar modelos matemáticos permite la adquisición efectiva de competencias matemáticas. Pero además, las actividades basadas en la modelización matemática pueden constituir elementos motivadores en el proceso de enseñanza/aprendizaje, despertando el interés del alumno hacia bases cognitivas sobre las cuáles se desarrollan conceptos matemáticos fundamentales en la formación matemática del futuro científico o ingeniero.Boigues Planes, FJ.; Estruch, VD.; Vidal Meló, A.; Roig, B. (2014). Reforzar la enseñanza de las matemáticas desde el primer curso de grado con proyectos. Editorial Universitat Politècnica de València. 741-752. http://hdl.handle.net/10251/168744S74175

An Approach to Measure Attitudes Towards Mathematics by Fuzzy Logic

[EN] This study examines engineering and science students' beliefs and attitudes toward mathematics through of the theory of fuzzy. Fuzzy logic provides a way to assess student attitudes towards mathematics which allows considering the relativity of their positions and structural relationships in the affective domain. The results show that to the engineering students like more the mathematics, they present a mathematical selfesteem higher and they believe that mathematics are more important in a manner significantly largest that the science students. The use of fuzzy logic has enabled us to design instruments and assess the affective dimension toward mathematics highlighting the fuzzy aspect of the assignment of truth and structural relationships inferred from theoretical models.[ES] Este estudio analiza las creencias y actitudes hacia las matemáticas de estudiantes de ingeniería y de ciencias a través de una metodología basada en la lógica fuzzy. La lógica fuzzy proporciona una forma de valorar las actitudes de los estudiantes hacia las matemáticas que permite considerar la relatividad de sus posiciones y las relaciones estructurales en el dominio afectivo. Los resultados muestran que los estudiantes de ingeniería les gustan más las matemáticas, presentan mayor autoestima matemática y creen que las matemáticas son importantes de un modo significativamente mayor que los estudiantes de ciencias. El uso de la lógica fuzzy ha permitido diseñar los instrumentos y valorar la dimensión afectiva en relación a las matemáticas, destacando el aspecto difuso de las atribuciones de verdad de las expresiones y de las relaciones estructurales inferidas desde los modelos teóricos.El proyecto ha sido financiado por el programa de Ayuda a Proyectos de Innovación Docente del Dpto. de Matemática Aplicada de la UPV (PID-DMA 2013).Boigues Planes, FJ.; Estruch, VD.; Vidal Meló, A.; Llinares Ciscar, S. (2017). Una aproximación a la medida de actitudes hacia las matemáticas mediante la lógica fuzzy. REDIMAT: Journal of Research in Mathematics Education. 6(1):85-111. https://doi.org/10.17583/redimat.2017.1935S851116

A survey of cost-sensitive decision tree induction algorithms

The past decade has seen a significant interest on the problem of inducing decision trees that take account of costs of misclassification and costs of acquiring the features used for decision making. This survey identifies over 50 algorithms including approaches that are direct adaptations of accuracy based methods, use genetic algorithms, use anytime methods and utilize boosting and bagging. The survey brings together these different studies and novel approaches to cost-sensitive decision tree learning, provides a useful taxonomy, a historical timeline of how the field has developed and should provide a useful reference point for future research in this field

Reduction in the Incidence of Type 2 Diabetes With the Mediterranean Diet: Results of the PREDIMED-Reus nutrition intervention randomized trial

OBJECTIVE - To test the effects of two Mediterranean diet (MedDiet) interventions versus a low-fat diet on incidence of diabetes. RESEARCH DESIGN AND METHODS - This was a three-arm randomized trial in 418 nondiabetic subjects aged 55-80 years recruited in one center (PREDIMED-Reus, northeastern Spain) of the Prevención con Dieta Mediterránea [PREDIMED] study, a large nutrition intervention trial for primary cardiovascular prevention in individuals at high cardiovascular risk. Participants were randomly assigned to education on a low-fat diet (control group) or to one of two MedDiets, supplemented with either free virgin olive oil (1 liter/week) or nuts (30 g/day). Diets were ad libitum, and no advice on physical activity was given. The main outcome was diabetes incidence diagnosed by the 2009 American Diabetes Association criteria. RESULTS - After a median follow-up of 4.0 years, diabetes incidence was 10.1% (95% CI 5.1-15.1), 11.0% (5.9 -16.1), and 17.9% (11.4 -24.4) in the MedDiet with olive oil group, the MedDiet with nuts group, and the control group, respectively. Multivariable adjusted hazard ratios of diabetes were 0.49 (0.25- 0.97) and 0.48 (0.24-0.96) in the MedDiet supplemented with olive oil and nuts groups, respectively, compared with the control group. When the two MedDiet groups were pooled and compared with the control group, diabetes incidence was reduced by 52% (27- 86). In all study arms, increased adherence to the MedDiet was inversely associated with diabetes incidence. Diabetes risk reduction occurred in the absence of significant changes in body weight or physical activity. CONCLUSIONS - MedDiets without calorie restriction seem to be effective in the prevention of diabetes in subjects at high cardiovascular risk. © 2011 by the American Diabetes Association.This study was funded, in part, by the Spanish Ministry of Health (Instituto de Salud Carlos III) (projects PI051839, PI070240, PI1001407, G03/140, and RD06/0045), Fondo Europeo de Desarrollo Regional, and the Public Health Division of the Department of Health of the Autonomous Government of Catalonia in collaboration with Merck Sharp & Dohme. The Fundación Patrimonio Comunal Olivarero and Hojiblanca SA (Málaga, Spain), California Walnut Commission (Sacramento, CA), Borges SA (Reus, Spain), and Morella Nuts SA (Reus, Spain) donated the olive oil, walnuts, almonds, and hazelnuts, respectively, used in the study.Peer Reviewe

El poder de la colaboración

[ES] La implantación del EEES ha dado lugar a que, además de las competencias específicas de cada materia o asignatura de los estudios de Grado, el alumnado adquiera otra serie de competencias de carácter transversal o genérico, como es la del trabajo en equipo. A la hora de abordar y de concretar el objetivo de la competencia del trabajo en grupo, existen diversas metodologías. En algunas de ellas, tras formarse los grupos, se plantean trabajos de forma que cada grupo resuelve un problema. En contraposición a este planteamiento, la propuesta metodológica que presentamos va en la línea de trabajar con grupos autónomos y colaborativos, potenciando la interacción colaborativa y cooperativa entre grupos distintos para la consecución de unas metas que serán comunes o estarán íntimamente relacionadas para los distintos grupos. En este artículo se exponen 4 de los trabajos planteados en las prácticas de la asignatura de Matemáticas 2 del primer curso del Grado de Ingeniería de Sistemas de Telecomunicación, Sonido e Imagen (GISTSI), desarrollados en base al trabajo en grupos autónomos y colaborativos. Algunos de los trabajos se han diseñado desde planteamientos multidisciplinares con la colaboración previa de profesores de distintas disciplinas. Se muestran también los productos obtenidos por el alumnado gracias al poder añadido que proporciona la colaboración.[Otros] The implementation of the EHEA has meant that students must acquire another set of cross-generic competences, as is the teamwork, in addition to the specific competences corresponding to each subject or course of the grade studies.When addressing and achieving the objective of the teamwork competence, there are several methodologies. In some of them, after forming the work teams, work is posed so that each group solves a problem. In contrast to the previous approach, the methodology presented is in line to work with independent and collaborative groups, promoting collaborative and cooperative interaction between different groups to achieve common goals, or goals closely related for the different groups. This article presents 4 of the works proposed in the subject Mathematics 2 GISTSI first course, developed based on working in autonomous and collaborative groups. Some of the works have been designed from multidisciplinary approaches, with the previous collaboration of teachers from different disciplines. Products obtained by students through the added power provided by collaboration, are also shown.Vidal Meló, A.; Roig, B.; Estruch, VD.; Boigues Planes, FJ.; Rey Tormos, RMD.; Alba, J.; Sapena Piera, A. (2014). El poder de la colaboración. Editorial Universitat Politècnica de València. 689-703. http://hdl.handle.net/10251/168753S68970

Stime della biomassa marina attraverso il metodo acustico: discernimento delle specie e gestione delle risorse ittiche

[EN] Acoustics is the basics of the most important technologies for underwater telecommunication, as well as for target detection and identification in the aquatic media. Multiple frequency measurements are the key for species discrimination and open the door for sustainable fisheries. The development of wider broadband systems and quantitative multi-beam sonars and processing techniques constitute the present challenge for scientists and developers. In parallel, simpler and cost-efficient systems like satellite buoys can offer clue information for marine ecosystem monitoring or target species fisheries.[IT] Acoustics is the basics of the most important technologies for underwater telecommunication, as well as for target detection and identification in the aquatic media. Multiple frequency measurements are the key for species discrimination and open the door for sustainable fisheries. The development of wider broadband systems and quantitative multi-beam sonars and processing techniques constitute the present challenge for scientists and developers. In parallel, simpler and cost-efficient systems like satellite buoys can offer clue information for marine ecosystem monitoring or target species fisheries.We acknowledge the Associazione Italiana di Acustica the invitation and the opportunity of participating in the Symposium The SCIENCE OF ACOUSTICS serving the Food, the Nutrition and the Environment: From protection system to innovative technologies for agriculture and fisheries”, at the EXPO Milan (Italy), in September 2015. E. soliveres acknowledges support of Spanish Government grant AP2009-4459 FPU Subprogram.Espinosa Roselló, V.; Calise, L.; Estruch, VD.; Llorens Escrich, S.; Ordoñez Cebrián, P.; Pérez Arjona, I.; Puig Pons, V.... (2015). Acoustical estimation of fish biomass: species identification and stocks management. Rivista Italiana di Acustica. 39(3):15-21. http://hdl.handle.net/10251/63737S152139

The Antioxidant Potential of the Mediterranean Diet in Patients at High Cardiovascular Risk: An In-Depth Review of the PREDIMED

Cardiovascular disease (CVD) is the leading global cause of death. Diet is known to be important in the prevention of CVD. The PREDIMED trial tested a relatively low-fat diet versus a high-fat Mediterranean diet (MedDiet) for the primary prevention of CVD. The resulting reduction of the CV composite outcome resulted in a paradigm shift in CV nutrition. Though many dietary factors likely contributed to this effect, this review focuses on the influence of the MedDiet on endogenous antioxidant systems and the effect of dietary polyphenols. Subgroup analysis of the PREDIMED trial revealed increased endogenous antioxidant and decreased pro-oxidant activity in the MedDiet groups. Moreover, higher polyphenol intake was associated with lower incidence of the primary outcome, overall mortality, blood pressure, inflammatory biomarkers, onset of new-onset type 2 diabetes mellitus (T2DM), and obesity. This suggests that polyphenols likely contributed to the lower incidence of the primary event in the MedDiet groups. In this article, we summarize the potential benefits of polyphenols found in the MedDiet, specifically the PREDIMED cohort. We also discuss the need for further research to confirm and expand the findings of the PREDIMED in a non-Mediterranean population and to determine the exact mechanisms of action of polyphenols

Primary prevention of cardiovascular disease with a Mediterranean diet

BACKGROUND: Observational cohort studies and a secondary prevention trial have shown an inverse association between adherence to the Mediterranean diet and cardiovascular risk. We conducted a randomized trial of this diet pattern for the primary prevention of cardiovascular events. METHODS: In a multicenter trial in Spain, we randomly assigned participants who were at high cardiovascular risk, but with no cardiovascular disease at enrollment, to one of three diets: a Mediterranean diet supplemented with extra-virgin olive oil, a Mediterranean diet supplemented with mixed nuts, or a control diet (advice to reduce dietary fat). Participants received quarterly individual and group educational sessions and, depending on group assignment, free provision of extra-virgin olive oil, mixed nuts, or small nonfood gifts. The primary end point was the rate of major cardiovascular events (myocardial infarction, stroke, or death from cardiovascular causes). On the basis of the results of an interim analysis, the trial was stopped after a median follow-up of 4.8 years. RESULTS: A total of 7447 persons were enrolled (age range, 55 to 80 years); 57% were women. The two Mediterranean-diet groups had good adherence to the intervention, according to self-reported intake and biomarker analyses. A primary end-point event occurred in 288 participants. The multivariable-adjusted hazard ratios were 0.70 (95% confidence interval [CI], 0.54 to 0.92) and 0.72 (95% CI, 0.54 to 0.96) for the group assigned to a Mediterranean diet with extra-virgin olive oil (96 events) and the group assigned to a Mediterranean diet with nuts (83 events), respectively, versus the control group (109 events). No diet-related adverse effects were reported. CONCLUSIONS: Among persons at high cardiovascular risk, a Mediterranean diet supplemented with extra-virgin olive oil or nuts reduced the incidence of major cardiovascular events