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Hybrid Optimized Fuzzy Pitch Controller of a Floating Wind Turbine with Fatigue Analysis
Get PDFFloating offshore wind turbines (FOWTs) are systems with complex and highly nonlinear
dynamics; they are subjected to heavy loads, making control with classical strategies a challenge. In
addition, they experience vibrations due to wind and waves. Furthermore, the control of the blade
angle itself may generate vibrations. To address this issue, in this work we propose the design of
an intelligent control system based on fuzzy logic to maintain the rated power of an FOWT while
reducing the vibrations. A gain scheduling incremental proportional–derivative fuzzy controller is
tuned by genetic algorithms (GAs) and combined with a fuzzy-lookup table to generate the pitch
reference. The control gains optimized by the GA are stored in a database to ensure a proper operation
for different wind and wave conditions. The software Matlab/Simulink and the simulation tool FAST
are used. The latter simulates the nonlinear dynamics of a real 5 MW barge-type FOWT with irregular
waves. The hybrid control strategy has been evaluated against the reference baseline controller
embedded in FAST in different environmental scenarios. The comparison is assessed in terms of
output power and structure stability, with up to 23% and 33% vibration suppression rate for tower
top displacement and platform pitch, respectively, with the new control scheme. Fatigue damage
equivalent load (DEL) of the blades has been also estimated with satisfactory results.This work has been partially supported by the Spanish Ministry of Science and Innovation under the project MCI/AEI/FEDER number RTI2018-094902-B-C21 and PDI2021-123543OB-C21
Odor Profile of Four Cultivated and Freeze-Dried Edible Mushrooms by Using Sensory Panel, Electronic Nose and GC-MS
Get PDFCultivated mushrooms are well-known nutrient inputs for an equilibrated diet. Some
species are broadly appreciated due to their medicinal properties. Lately, a number of novel foods and
nutraceuticals based on dehydrated and freeze-dried powder obtained from cultivated mushrooms
has been reaching the market. The food industry requires fast and reliable tools to prevent fraud. In
this, work we have cultivated Agaricus bisporus sp. bisporus (AB) (white button mushroom), Agaricus
bisporus sp. brunnescens (ABP) (portobello), Lentinula edodes (LE) (shiitake) and Grifola frondosa (GF)
(maitake) using tailor-made substrates for the different species and standardized cropping conditions,
which were individually freeze-dried to obtain the samples under evaluation. The aim of this article
was to validate the use of two different methodologies, namely, electronic nose and sensory panel,
to discriminate the olfactory profile of nutritional products based on freeze-dried mushrooms from
the different cultivated species. Additionally, GC-MS was used to detect and quantify the most
abundant volatile organic compounds (VOCs) in the samples. The multivariate analysis performed
proved the utility of electronic nose as an analytical tool, which was similar to the classical sensory
panel but faster in distinguishing among the different species, with one limitation it being unable to
differentiate between the same species. GC-MS analysis showed the chemical volatile formulation
of the samples, also showing significant differences between different samples but high similarities
between varieties of the same cultivated species. The techniques employed can be used to prevent
fraud and have the potential to evaluate further medicinal mushroom species and build solid and
trustful connections between these novel food products and potential consumers.This research was partially financed by the Department of Economic Development and Innovation of La Rioja. Res. no 1168/2018
Effects of Citrulline Supplementation on Different Aerobic Exercise Performance Outcomes: A Systematic Review and Meta-Analysis
Get PDFSupplementation with Citrulline (Cit) has been shown to have a positive impact on aerobic
exercise performance and related outcomes such as lactate, oxygen uptake (VO2
) kinetics, and the rate
of perceived exertion (RPE), probably due to its relationship to endogenous nitric oxide production.
However, current research has shown this to be controversial. The main objective of this systematic
review and meta-analysis was to analyze and assess the effects of Cit supplementation on aerobic
exercise performance and related outcomes, as well as to show the most suitable doses and timing
of ingestion. A structured literature search was carried out by the PRISMA® (Preferred Reporting
Items for Systematic Reviews and Meta-Analyses) and PICOS guidelines in the following databases:
Pubmed/Medline, Scopus, and Web of Science (WOS). A total of 10 studies were included in the
analysis, all of which exclusively compared the effects of Cit supplementation with those of a placebo
group on aerobic performance, lactate, VO2
, and the RPE. Those articles that used other supplements
and measured other outcomes were excluded. The meta-analysis was carried out using Hedges’ g
random effects model and pooled standardized mean differences (SMD). The results showed no
positive effects of Cit supplementation on aerobic performance (pooled SMD = 0.15; 95% CI (−0.02 to
0.32); I
2
, 0%; p = 0.08), the RPE (pooled SMD = −0.03; 95% CI (−0.43 to 0.38); I
2
, 49%; p = 0.9), VO2
kinetics (pooled SMD = 0.01; 95% CI (−0.16 to 0.17); I
2
, 0%; p = 0.94), and lactate (pooled SMD = 0.25;
95% CI (−0.10 to 0.59); I
2
, 0%; p = 0.16). In conclusion, Cit supplementation did not prove to have
any benefits for aerobic exercise performance and related outcomes. Where chronic protocols seemed
to show a positive tendency, more studies in the field are needed to better understand the effects
Determinants of Lack of Recovery from Dependency and Walking Ability Six Months after Hip Fracture in a Population of People Aged 65 Years and Over
Get PDFHip fracture in the elderly means that between a quarter and a half of patients
do not regain the levels of independence and walking ability that they previously had, according
to the literature, after the fracture
Effectiveness of Comirnaty® Vaccine and Correlates of Immunogenicity and Adverse Reactions: A Single-Center Prospective Case Series Study
Get PDFThe literature suggests that real-world data on the effectiveness and safety of the BNT162b2
vaccine depend on the characteristics of the vaccinated volunteers. The purpose of this study was to
evaluate antibody responses and kinetics, established association with sociodemographic and clinical characteristics, and adverse reactions after complete vaccination with the BNT162b2 vaccine. A
single-center prospective case series study was conducted with 112 eligible volunteers who were
institutionalized elderly and health care workers with had a negative anti-SARS-CoV-2 IgG test prior
to receiving the first dose of vaccine. At least one serological antibody test after each dose of vaccine
was performed. Volunteers with a positive SARS-CoV-2 PCR test before vaccination were excluded.
A chemiluminescent immunoassay anti-S1 antibody assay performed a serological evaluation. Both
vaccine doses elicited positive IgG antibodies 3799.0 ± 2503.0 AU/mL and 8212.0 ± 4731.0 AU/mL
after 20 days of the first and second doses of BNT162b2, respectively. Comirnaty® vaccine induced
an immune response with antibody production against SARS-CoV-2 in 100% of participants, regardless of age (Spearman rho = −0.10, p-value = 0.312), body mass index (Spearman rho = 0.05,
p-value = 0.640), blood group first dose (p-value for Kruskal–Wallis test = 0.093) and second dose
(p-value for Kruskal–Wallis test = 0. 268), number of drugs (Spearman rho = −0.07, p-value = 0.490),
and number of chronic diseases first dose (p-value for Kruskal–Wallis test = 0.632) and second dose
(p-value for Kruskal–Wallis test = 0.510). IgG antibodies to SARS-CoV-2 were intensely elevated after
the second administration of the BNT162b2 vaccine. The higher the titer of anti-peptide IgG antibodies
generated after the first dose of vaccine, the higher the titer generated by the second dose of vaccine
(Spearman rho = 0.86, p-value < 0.001) and the total antibody titer (Spearman rho = 0.93, p-value < 0.001).
Furthermore, no serious adverse effects were reported among participants, although mild to moderate
adverse effects (local or systemic) were reported after both doses of the BNT162b2 vaccine, being more
frequent after the first dose of the vaccine. No participants showed a positive PCR. The BNT162b2
vaccine induces a robust and rapid antibody response regardless of participant characteristics. The second dose might be especially important because of the increased immunogenicity it produces and the
possible temporal distancing of the interval between doses. In general, the vaccines were well tolerated.This research was funded by (i) Chair of Knowledge and Innovation “Caja Rural de Soria” (Spain) in the call for funding research projects related to the COVID-19 pandemic. With project number SO-2-2020; (ii) Call for expressions of interest for the funding of research projects on SARS-CoV-2 and COVID-19 disease by the FONDO-COVID-19 n 07.04.467804.74011.0 within the framework of Royal Decree Law 8/2020 of 17 March on extraordinary urgent measures to deal with the economic and social impact of COVID-19. Financed by the FEDER and the Junta of Castilla-Leon, Spain
Effects of Tribulus terrestris L. on Sport and Health Biomarkers in Physically Active Adult Males: A Systematic Review
Get PDFTribulus terrestris L. (TT) is a plant used in traditional Chinese medicine, Ayurvedic medicine,
and sports nutrition to improve health and performance. However, no conclusive evidence exists
about the potential beneficial effects of TT on sport and health biomarkers in physically active
adults. Based on the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA)
guidelines, and the modified McMaster Critical Review Form for methodological quality assessment,
we systematically reviewed studies indexed in Web of Science, Scopus, and PubMed, to assess
the effects of TT on immunological, hematological, biochemical, renal, lipidic, hormonal behavior,
and anti-inflammatory response in physically active adult males. Among 340 records identified
in the search, a total of 7 studies met the inclusion and exclusion criteria. Overall, participants
supplemented with TT displayed significant improvements in lipid profile. Inflammatory and
hematological biomarkers showed moderate beneficial effects with no significant changes on renal
biomarkers. No positive effects were observed on the immune system response. Additionally, no
TT-induced toxicity was reported. In conclusion, there was no clear evidence of the beneficial effects
of TT supplementation on muscle damage markers and hormonal behavior. More studies are needed
to confirm the benefits of TT due to the limited number of studies available in the current literature
Psychometric Analysis and Contribution to the Evaluation of the Exams-Related Emotions Scale in Primary and Secondary School Students
Get PDFThe objective of this research was to perform a construct validity, and a psychometric
analysis of the Exams-related Emotions Scale (EES), analyze the differences in their scores regarding
gender and academic year in primary and secondary education student, as well as study the relationship between emotions and academic performance. During the construction and analysis of the
psychometric characteristics of the scale, an Exploratory Factor Analysis (EFA) and a Confirmatory
Factor Analysis (CFA) were performed. To test EES scores based on gender and school year, the
T-Student test for independent samples and ANOVA were used, respectively. To verify the relationship between the scores of the different types of emotions and academic performance, the Pearson
correlation test was performed. A total of 562 students belonging to the 5th (n = 228) and 6th (n = 186)
primary school year and the 1st (n = 134) and 2nd (n = 94) secondary school year participated in the
research. Age between 10 and 15 years old (mean = 11.66, standard deviation = 1.206) both males
(50.5%) and females (49.5%). The results offered support for the three-factor structure. The analysis
of invariance with respect to gender showed that the factor structure was invariant. Boys scored
higher on the positive emotions factor and lower scores on anxiety than girls. Regarding school
year, negative emotions and anxiety related to exams increase in the secondary courses compared
to Primary while for positive emotions it is primary school students who obtain higher scores. The
correlation coefficient between negative emotions (as well as anxiety) and school performance is
negative whereas the correlation coefficient between positive emotions and academic performance is
positive. EES scale is an instrument with scientific rigor and with adequate reliability and validity
to be able to know the emotions that primary and secondary school students suffer when they are
subjected to evaluation processes in the academic context
Humidity forecasting in a potato plantation using time-series neural models
Get PDFIt is widely acknowledged that, under the frame of sustainable farming, using the minimum water resources is a relevant requirement. In order to do that, precision irrigation aims at identifying the irrigation needs of plantations and irrigate accordingly. Artificial intelligence is a promising solution in this field as intelligent models are able to learn the soil moisture dynamics in the soil-plant-atmosphere system and then generating appropriate irrigation scheduling. This is a complex task as the phenology of plants and its water demand vary with soil properties and weather conditions. The present research contributes to this challenging task by proposing the application of neural networks in order to learn the time-series evolution of irrigation needs associated to a potato plantation. Several of such models are thoroughly compared, together with different interpolation methods, in order to find the best combination for accurately forecasting water needs. In order to predict the soil water content in a potato field crop, in which soil humidity probes were installed at 15, 30, and 45 cm depth during the whole cycle of a potato crop. This innovative study and its promising results provide with significant contributions to address the problem of predicting and managing groundwater for agricultural use in a sustainable way.Lab-Ferrer (METER Group) and the UBUCOMP research group at the University of Burgos