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[Abstract] The problem of testing the equality of generating processes of two multivariate time series is addressed in this work. To this end, we construct two tests based on a distance measure between stochastic processes. The metric is defined in terms of the quantile cross-spectral densities of both processes. A proper estimate of this dissimilarity is the cornerstone of the proposed tests. Both techniques are based on the bootstrap. Specifically, extensions of the moving block bootstrap and the stationary bootstrap are used for their construction. The approaches are assessed in a broad range of scenarios under the null and the alternative hypotheses. The results from the analyses show that the procedure based on the stationary bootstrap exhibits the best overall performance in terms of both size and power. The proposed techniques are used to answer the question regarding whether or not the dotcom bubble crash of the 2000s permanently impacted global market behavior. This research has been supported by MINECO (MTM2017-82724-R and PID2020-113578RB-100), the Xunta de Galicia (ED431C-2020-14), and “CITIC” (ED431G 2019/01) Xunta de Galicia; ED431C-2020-14 Xunta de Galicia; ED431G 2019/01

Presented at the 4th XoveTIC Conference, A Coruña, Spain, 7–8 October 2021. [Abstract] Three robust algorithms for clustering multidimensional time series from the perspective of underlying processes are proposed. The methods are robust extensions of a fuzzy C-means model based on estimates of the quantile cross-spectral density. Robustness to the presence of anomalous elements is achieved by using the so-called metric, noise and trimmed approaches. Analyses from a wide simulation study indicate that the algorithms are substantially effective in coping with the presence of outlying series, clearly outperforming alternative procedures. The usefulness of the suggested methods is also highlighted by means of a specific application. This research has been supported by MINECO (MTM2017-82724-R and PID2020-113578RB-100), the Xunta de Galicia (ED431C-2020-14), and “CITIC” (ED431G 2019/01). Xunta de Galicia; ED431C-2020-14 Xunta de Galicia; ED431G 2019/01

The effect of a ketogenic diet (KD) on biochemical parameters and nutritional status has been the subject of debate over the years, as several randomized clinical trials (RCTs) obtained different results. Method: A systematic review and random-effects meta-analysis of RCTs comparing KD with a balanced diet was performed by means of a search of PubMed, Cochrane Library, Scopus, and Web of Science. Trials where the method for measuring the response variables was unclear, those that considered pathologies other than chronic non-communicable diseases and those with participants receiving pharmacological treatment for obesity were excluded from the comparison. Results: Of the studies included in the meta-analysis, no statistically significant standardized mean differences were observed for body mass index (BMI) (d = −0.457, p = 0.359), total cholesterol, COL-T (d = 0.230, p = 0.591), high-density lipoprotein, HDL (d = −0.028, p = 0.934), low-density lipoprotein, LDL (d = 0.528, p = 0.173), or triglycerides, TG (d = −0.283, p = 0.222), with high values of heterogeneity. The percentage of women included in the studies is a significant moderating variable in terms of BMI ratio (z = −6.68, p < 0.001) and TG (z = −2.27, p = 0.023). Conclusion: A KD shows no more benefits on nutritional parameters than a balanced diet, and adverse effects of being on the diet are sometimes reported. Fondo Nacional de Desarrollo Científico y Tecnológico FONDECYT Regular, CONICYT 1190945 Programa Operativo FEDER Andalucía 2014–2020 US-1263096

Procalcitonin (PCT) is a known protein biomarker clinically used for the early stages of sepsis diagnosis and therapy guidance. For its reliable determination, sandwich format magnetic bead-based immunoassays with two different electrochemical detection approaches are described: (i) disposable screen-printed carbon electrodes (SPE-C, on-drop detection), (ii) electro-kinetically driven microfluidic chips with integrated Au electrodes (EMC-Au, on-chip detection). Both approaches exhibited enough sensitivity (limit of detection (LOD) of 0.1 and 0.04 ng mL&minus, 1 for SPE-C and EMC-Au, respectively, cutoff 0.5 ng mL&minus, 1), an adequate working range for the clinically relevant concentrations (0.5&ndash, 1000 and 0.1&ndash, 20 ng mL&minus, 1 for SPE-C and EMC-Au, respectively), and good precision (RSD &lt, 9%), using low sample volumes (25 &micro, L) with total assay times less than 20 min. The suitability of both approaches was successfully demonstrated by the analysis of human serum and plasma samples, for which good recoveries were obtained (89&ndash, 120%). Furthermore, the EMC-Au approach enabled the easy automation of the process, constituting a reliable alternative diagnostic tool for on-site/bed-site clinical analysis.

This article belongs to the Special Issue Bioactive Compounds Derived from Marine Microalgae 2.0., Polyunsaturated aldehydes (PUAs) are bioactive molecules suggested as chemical defenses and infochemicals. In marine coastal habitats, diatoms reach high PUA production levels during bloom episodes. Two fractions of PUA can usually be analyzed: pPUA obtained via artificial breakage of collected phytoplankton cells and dissolved PUA already released to the environment (dPUA). In nature, resource supply arises as a main environmental controlling factor of PUA production. In this work, we monitored the vertical distribution and daily variation of pPUA associated with large-size phytoplankton and dPUA, at three sites located in the Alborán Sea from mesotrophic to oligotrophic waters. The results corroborate the presence of large-size PUA producers in oligotrophic and mesotrophic waters with a significant (58%–85%) diatom biomass. In addition to diatoms, significant correlations between pPUA production and dinoflagellate and silicoflagellate abundance were observed. 2E,4E/Z-Heptadienal was the most abundant aldehyde at the three sites with higher values (17.1 fg·cell−1) at the most oligotrophic site. 2E,4E/Z-Decadienal was the least abundant aldehyde, decreasing toward the oligotrophic site. For the first time, we describe the daily fluctuation of pPUA attributable to cellular physiological state and not exclusively to taxonomical composition. Our results demonstrate the persistence of threshold levels of dPUA deep in the water column, as well as the different chromatographic profiles of dPUA compared with pPUA. We propose different isomerization processes that alter the chemical structure of the released PUAs with unknown effects on their stability, biological function, and potential bioactivity., This work was supported by the projects MEGAN (CTM2013-49048-C2-1-R) and FICOEXPLORA (RTI2018-101272-B-I00) funded by the Spanish National Research Plan. I.S. and M.B.-P. are supported by a grant of the FPI fellowship program.

The objective of this research is to present an innovative and successful active learning experience aimed at enabling the development of students’ knowledge, skills and engagement in a Higher Education setting—the Je Suis Econplus experience.

Today, there is widespread consensus about the notable, yet simultaneously growing, negative environmental impacts generated by the transportation sector. Experts working in a number of different fields consider the current situation to be unsustainable and possible measures to reduce emissions and foster sustainability are being encouraged. The European Commission has highlighted the need to shift away from unimodal road transport toward a greater use of intermodal transport through, for example, motorways of the sea, in light of the evidence that the former makes a significant contribution to increased CO 2 emissions. However, although there is a general perception that sea transport is environmentally preferable to road transport, recent studies are beginning to question this assumption. Moreover, little research has been conducted to quantify environmental aspects and incorporate them into the decision-making processes involved in the modal shift. This study first reviews the existing literature to examine the extent to which environmental aspects are relevant in the modal choice in the case of short sea shipping and motorways of the sea. Related to this, the study also evaluates the role that different agents may play in making decisions about choice of mode, taking into consideration environmental aspects. Secondly, we use the values the European Commission provides to calculate external costs for the Marco Polo freight transport project proposals (call 2013) to estimate the environmental costs for several routes (a total of 72), comparing the use of road haulage with the intermodal option that incorporates the Spanish motorways of the sea. The results of this comparative analysis show that the intermodal option is not always the best choice in environmental terms. Consequently, the traditional environmental argument to justify this alternative must be used carefully.