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Abstract Films of ferroelectric hafnia have hitherto been deposited on electrodes with a non‐fluorite crystal structure. As a result, they are polycrystalline, contain fractions of non‐ferroelectric polymorphs or have poor crystal quality. Here, a strategy that circumvents all these limitations is shown. Seven nanometers‐thick epitaxial Hf0.5Zr0.5O2 (HZO) films are deposited directly on yttria‐stabilized zirconia (YSZ) single‐crystals. The fluorite structure of the whole system enables coherent epitaxy, while the substrate orientation induces polymorph‐selective growth, being the HZO films orthorhombic on YSZ(111) and monoclinic on YSZ(001). Besides, the YSZ substrate can play the role of a buried floating electrode under the appropriate measuring conditions (temperature and frequency) thanks to its thermally‐activated oxygen conductivity. Indeed, out‐of‐plane ferroelectric switching is confirmed in the orthorhombic HZO samples at 185 °C and 0.01 Hz frequency. This original approach avoids the need to deposit conducting bottom layers, allowing high‐quality orthorhombic hafnia to be obtained directly on the substrate and its ferroelectric nature to be studied. Moreover, it constitutes a case of ion‐driven ferroelectric switching, and thus gives support to the recently proposed relationship between ionic conductivity, and ferroelectricity in fluorite systems.

Despite the fact that the first red tide reported on the coasts of the Iberian Peninsula was due to Lingulodinium polyedra, knowledge about their frequency and, particularly, about the environmental conditions contributing to bloom initiation is still scarce. For this reason, L. polyedra bloom episodes were observed and studied in three Galician rias during the summer season based on the 1993–2008 record database period; additionally, samples were collected in summer 2008. Proliferations of L. polyedra occurred in the rias of Ares and Barqueiro in June and August, respectively, while in the Ria of Coruña, they persisted from the end of June to early September. Red tides developed when the surface temperature reached 17 °C, with “seasonal thermal window” conditions, and when salinities were ≥30, i.e., an “optimal salinity window”; when these parameters were lower than these thresholds, cyst germination decreased. A cyst transport mechanism from sediments to the surface must also exist; this mechanism was found to be natural (tidal currents) in the ria of Barqueiro or anthropogenic (dredging) in the rias of Ares and Coruña. Surface temperatures during summer were usually favorable for cyst germination (85 to 100%) during the 1993–2008 period; however, water temperatures below 10 m depth only rarely reached the 17 °C threshold (2 to 18%). During this 16-year period, dredging activities could explain 71% (Coruña) and 44% (Ares) of the recorded bloom events. When a bloom episode developed in early summer, favorable conditions did not lead to a new red tide, probably due to the lag period required by cysts for germination. Moreover, blooms did not develop when high densities of diatoms (>1,000,000 cells·L−1) remained in the water column as a result of summer upwelling pulses occurring in specific years. The temperature–sediment disturbance pattern found in this study provides a useful tool for the prevention of eventual risks resulting from red tides of this dinoflagellate.

Body temperature is usually employed in clinical practice by strict binary thresholding, aiming to classify patients as having fever or not. In the last years, other approaches based on the continuous analysis of body temperature time series have emerged. These are not only based on absolute thresholds but also on patterns and temporal dynamics of these time series, thus providing promising tools for early diagnosis. The present study applies three time series entropy calculation methods (Slope Entropy, Approximate Entropy, and Sample Entropy) to body temperature records of patients with bacterial infections and other causes of fever in search of possible differences that could be exploited for automatic classification. In the comparative analysis, Slope Entropy proved to be a stable and robust method that could bring higher sensitivity to the realm of entropy tools applied in this context of clinical thermometry. This method was able to find statistically significant differences between the two classes analyzed in all experiments, with sensitivity and specificity above 70% in most cases.

Complexity analysis of glucose time series with Detrended Fluctuation Analysis (DFA) has been proved to be useful for the prediction of type 2 diabetes mellitus (T2DM) development. We propose a modified DFA algorithm, review some of its characteristics and compare it with other metrics derived from continuous glucose monitorization in this setting. Several issues of the DFA algorithm were evaluated: (1) Time windowing: the best predictive value was obtained including all time-windows from 15 minutes to 24 hours. (2) Influence of circadian rhythms: for 48-hour glucometries, DFA alpha scaling exponent was calculated on 24-hour sliding segments (1-hour gap, 23-hour overlap), with a median coefficient of variation of 3.2%, which suggests that analysing time series of at least 24-hour length avoids the influence of circadian rhythms. (3) Influence of pretreatment of the time series through integration: DFA without integration was more sensitive to the introduction of white noise and it showed significant predictive power to forecast the development of T2DM, while the pretreated time series did not. (4) Robustness of an interpolation algorithm for missing values: The modified DFA algorithm evaluates the percentage of missing values in a time series. Establishing a 2% error threshold, we estimated the number and length of missing segments that could be admitted to consider a time series as suitable for DFA analysis. For comparison with other metrics, a Principal Component Analysis was performed and the results neatly tease out four different components. The first vector carries information concerned with variability, the second represents mainly DFA alpha exponent, while the third and fourth vectors carry essentially information related to the two "pre-diabetic behaviours" (impaired fasting glucose and impaired glucose tolerance). The scaling exponent obtained with the modified DFA algorithm proposed has significant predictive power for the development of T2DM in a high-risk population compared with other variability metrics or with the standard DFA algorithm.

Diabetes is a disease of great and rising prevalence, with the obesity epidemic being a significant contributing risk factor. Duodenal–jejunal bypass liner (DJBL) is a reversible implant that mimics the effects of more aggressive surgical procedures, such as gastric bypass, to induce weight loss. We hypothesized that DJBL also influences the glucose dynamics in type II diabetes, based on the induced changes already demonstrated in other physiological characteristics and parameters. In order to assess the validity of this assumption, we conducted a quantitative analysis based on several nonlinear algorithms (Lempel–Ziv Complexity, Sample Entropy, Permutation Entropy, and modified Permutation Entropy), well suited to the characterization of biomedical time series. We applied them to glucose records drawn from two extreme cases available of DJBL implantation: before and after 10 months. The results confirmed the hypothesis and an accuracy of 86.4% was achieved with modified Permutation Entropy. Other metrics also yielded significant classification accuracy results, all above 70%, provided a suitable parameter configuration was chosen. With the Leave–One–Out method, the results were very similar, between 72% and 82% classification accuracy. There was also a decrease in entropy of glycaemia records during the time interval studied. These findings provide a solid foundation to assess how glucose metabolism may be influenced by DJBL implantation and opens a new line of research in this field.

Two main weaknesses have been identified for permutation entropy (PE): the neglect of subsequence pattern differences in terms of amplitude and the possible ambiguities introduced by equal values in the subsequences. A number of variations or customizations to the original PE method to address these issues have been proposed in the scientific literature recently. Specifically for ties, methods have tried to remove the ambiguity by assigning different weighted or computed orders to equal values. Although these methods are able to circumvent such ambiguity, they can substantially increase the algorithm costs, and a general characterization of their practical effectiveness is still lacking. This paper analyses the performance of PE using several biomedical datasets (electroencephalogram, heartbeat interval, body temperature, and glucose records) in order to quantify the influence of ties on its signal class segmentation capability. This capability is assessed in terms of statistical significance of the PE differences between classes and classification sensitivity and specificity. Being obvious that ties modify the PE results, we hypothesize that equal values are intrinsic to the acquisition process, and therefore, they impact all the classes more or less equally. The experimental results confirm ties are often not the limiting factor for PE, even they can be beneficial as a sort of stochastic resonance, and it can be far more effective to focus on the embedding dimension instead.

Detrended Fluctuation Analysis (DFA) measures the complexity of a glucose time series obtained by means of a Continuous Glucose Monitoring System (CGMS) and has proven to be a sensitive marker of glucoregulatory dysfunction. Furthermore, some authors have observed a crossover point in the DFA, signalling a change of dynamics, arguably dependent on the beta-insular function. We investigate whether the characteristics of this crossover point have any influence on the risk of developing type 2 diabetes mellitus (T2DM). To this end we recruited 206 patients at increased risk of T2DM (because of obesity, essential hypertension, or a first-degree relative with T2DM). A CGMS time series was obtained, from which the DFA and the crossover point were calculated. Patients were then followed up every 6 months for a mean of 17.5 months, controlling for the appearance of T2DM diagnostic criteria. The time to crossover point was a significant predictor risk of developing T2DM, even after adjusting for other variables. The angle of the crossover was not predictive by itself but became significantly protective when the model also considered the crossover point. In summary, both a delay and a blunting of the crossover point predict the development of T2DM.

En este trabajo se analizan las estrategias relativas al proceso de internacionalización de la propiedad dentro del sector pesquero comunitario (en particular la conocida como “quota hopping”, aplicada sobre todo por el sector pesquero español). En el desarrollo del proceso ha surgido un conflicto derivado de la defensa del carácter nacional de las cuotas asignadas en la Unión Europea siguiendo el Principio de Estabilidad Relativa. La implantación consiguiente de medidas proteccionistas tales como la exigencia de “vínculos económicos” ha alterado el contexto en que los agentes involucrados en el proceso de internacionalización tomaban sus decisiones. En nuestro artículo analizamos las diferentes estrategias y valoramos los resultados.

Many entropy-related methods for signal classification have been proposed and exploited successfully in the last several decades. However, it is sometimes difficult to find the optimal measure and the optimal parameter configuration for a specific purpose or context. Suboptimal settings may therefore produce subpar results and not even reach the desired level of significance. In order to increase the signal classification accuracy in these suboptimal situations, this paper proposes statistical models created with uncorrelated measures that exploit the possible synergies between them. The methods employed are permutation entropy (PE), approximate entropy (ApEn), and sample entropy (SampEn). Since PE is based on subpattern ordinal differences, whereas ApEn and SampEn are based on subpattern amplitude differences, we hypothesized that a combination of PE with another method would enhance the individual performance of any of them. The dataset was composed of body temperature records, for which we did not obtain a classification accuracy above 80% with a single measure, in this study or even in previous studies. The results confirmed that the classification accuracy rose up to 90% when combining PE and ApEn with a logistic model.

We describe a device for dual channel body temperature monitoring. The device can operate as a real time monitor or as a data logger, and has Bluetooth capabilities to enable for wireless data download to the computer used for data analysis. The proposed device is capable of sampling temperature at a rate of 1 sample per minute with a resolution of 0.01 °C. The internal memory allows for stand-alone data logging of up to 10 days. The device has a battery life of 50 hours in continuous real-time mode. In addition to describing the proposed device in detail, we report the results of a statistical analysis conducted to assess its accuracy and reproducibility.

Bacterial abundance, biomass and heterotrophic activity, along with hydrographic and phytoplankton variables, were measured from February 1998 to September 1999 at two coastal stations off A Coruña (Galicia, NW Spain). Bacterial abundance varied from 0.1 to 1.8 x 106 cells ml-1 and water-column integrated bacterial production ranged from 34 to 1132 mg C m-2 d-1. Two annual maxima of bacterial abundance and production were observed, in spring and summer, although relatively high abundance values remained until autumn. In autumn and winter production values were low with the exception of the results obtained in November 1998, when the highest values of bacterial production of the whole study were observed at both stations. Bacterial biomass constituted a significant, but low, fraction of particulate organic carbon (4-21 %) and was always lower than phytoplankton biomass (up to 40% of phytoplankton carbon). Also, bacterial production was generally < 30% of primary production, but in some situations (as in early spring or in autumn) bacterial production exceeded primary production, suggesting a delayed response of bacterial activity after a phytoplankton bloom.

Phytoplankton species composition, chlorophyll-a concentrations and primary production were studied in the Rias of Ares, Ferrol and the Bay of La Coruña (Galicia, NW Spain) in three oceanographic situations during 1993. The observations were representative of maxima and minima phytoplankton biomass and production values in this area during the seasonal cycle. A phytoplankton bloom studied in March, was characterized by a patchy distribution of chlorophyll and high primary production rates, especially near La Coruña and in the Ria de Ferrol. High phytoplankton biomass and production was also recorded in August, when an upwelling pulse allowed for enhanced growth. Diatoms were very abundant during these blooms but while Chaetoceros socialis was the dominant species in spring other species dominated in summer, when dinoflagellates and flagellates increased. In contrast, the phytoplankton observed in December had low abundances, and correspondingly low chlorophyll concentrations and primary production rates through the study area. Photosynthetic measurements at selected stations using P-I curves indicated that phytoplankton populations were well adapted to the existing light regime. The main source of variation in photosynthetic parameters was seasonal, and no significant differences resulted between rias. Using these parameters and the measured vertical profiles of chlorophyll and irradiance, areal estimations of primary production rates were made for the entire area studied. The resulting values were scaled to the rates measured using parallel simulated in situ incubations of phytoplankton. Maximum primary production values during blooms exceeded 2400 mg C m-2 d-1, whereas values estimated for the winter cruise were lower than 20 mg C m-2 d-1. These values are equivalent to those available for the nearby Rias Baixas, but because of the larger size of the latter the annual values of the studied Rias Altas were less than 10% of the reported primary production in the most productive Galician ria (Ria de Arousa). This study provides the first estimates of up-to-date primary production values for the Rias Altas, and points out the differential role of upwelling in the nearby shelf compared to its effects on the Rias Baixas region. Upwelling events occur in localized areas outside the Rias Altas, and their associated water dynamics may cause a large export of the produced organic matter to outer shelf areas. In contast, upwelling has been detected well inside most Rias Baixas, inducing high accumulations of recently produced organic matter, that are exported to nearby coastal areas.

En este trabajo se intenta valorar la posición de Galicia en el contexto de las nuevas tendencias en la pesca mundial y comunitaria. Para ello, además de sintetizar los cambios más significativos en estos escenarios, recogemos argumentos esenciales de las discusiones económicas recientes sobre regulación de pesquerías, a fin de sustentar nuestras reflexiones finales sobre las perspectivas inmediatas de la pesca gallega.

En este número de nuestra revista se publica un estudio que aplica la ecografía clínica multiórgano al paciente ingresado por infección por SARS-CoV2 1. Entre los hallazgos principales, que otros estudios han refrendado, destacan la elevada sensibilidad y concordancia de los hallazgos de eco y TC en la neumonía COVID2. Así, en el paciente COVID ingresado por repercusión pulmonar no veíamos ecografías normales, y sí un número muy significativo de Rx tórax sin hallazgos significativos, como también se refleja en el estudio. La ecografía pulmonar nos permitió diagnosticar, estadificar mejor, y demostrar imitadores o problemas coexistentes (p.ej. neumonía alveolar, con patrón ecográfico muy distinto).

Outpatient parenteral antimicrobial therapy (OPAT) with continuous infusion pumps is postulated as a very promising solution to treat complicated infections, such as endocarditis or osteomyelitis, that require patients to stay in hospital during extended periods of time, thus reducing their quality of life and increasing the risk of complications. However, stability studies of drugs in elastomeric devices are scarce, which limits their use in OPAT. Therefore, we evaluated the stability of ampicillin in sodium chloride 0.9% at two different concentrations, 50 and 15 mg/mL, in an elastomeric infusion pump when stored in the refrigerator and subsequently in real-life conditions at two different temperatures, 25 and 32 °C, with and without the use of a cooling device. The 15 mg/mL ampicillin is stable for up to 72 h under refrigeration, allowing subsequent dosing at 25 °C for 24 h with and without a cooling device, but at 32 °C its concentration drops below 90% after 8 h. In contrast, 50 mg/mL ampicillin only remains stable for the first 24 h under refrigeration, and subsequent administration at room temperature is not possible, even with the use of a cooling system. Our data support that 15 mg/mL AMP is suitable for use in OPAT if the volume and rate of infusion are tailored to the dosage needs of antimicrobial treatments.

O Conservatório – Escola Profissional das Artes da Madeira agrega em si uma série de dez polos descentralizados (designados atualmente como núcleos) pelos diversos concelhos da Região Autónoma da Madeira. Estes, por sua vez, têm a particularidade de serem coordenados pela figura do Coordenador de núcleo, nomeado pela Direção desta instituição. Neste estudo, pretendeu-se verificar quais as motivações manifestadas pelos coordenadores de núcleo para o exercício do encargo supracitado, aliadas ao reconhecimento dado pela hierarquia superior. Contudo, vislumbra-se um certo desalinhamento no que concerne às motivações de cada Coordenador, acabando por refletir uma panóplia de entendimentos diferenciados, dos diferentes sujeitos, relativamente ao modo de vivenciar o cargo de coordenador de núcleo.

The challenges that today the Ecuadorian society faces, demand the elevation of the quality in the formation of highly qualified professionals in the area of Economy and entrepreneurship, which may contribute in the finding of solutions as signals of changes and thus become the nucleus in the transformations that the country needs. This article has as main goal to reveal some ideas about the cultural financial formation of the technologist in Higher Education, which is supported in the curricular content of Financial Economy and in the determination of the formative intention in the entrepreneur context, from the perspective of the unity between school- enterprises. During this research some theoretical and empirical methods were used, which allowed to verify the insufficiencies within the process of formation of the financial economic culture in the technicians – to-be.

The financial and economic culture in the formation process of technicians in enterprise management is a challenge, and at the same times a necessity. Therefore, its importance in the study of different alternatives to provide solution that may favor not only its appropriation, but also its material realization in the different contexts of performance. However, today there are still insufficiencies in their pedagogical treatment, which limit the actual performance of the technicians- to-be, due in many cases, to the lack of pedagogical methods for their treatment. The present article aims at revealing, as proposal of solution, the method of enterprise financial transversality, a methodological alternative for the creation of an economic financial culture.