91 research outputs found
Development of a Low-Cost Optical Sensor to Detect Eutrophication in Irrigation Reservoirs
[EN] In irrigation ponds, the excess of nutrients can cause eutrophication, a massive growth of microscopic algae. It might cause different problems in the irrigation infrastructure and should be monitored. In this paper, we present a low-cost sensor based on optical absorption in order to determine the concentration of algae in irrigation ponds. The sensor is composed of 5 LEDs with different wavelengths and light-dependent resistances as photoreceptors. Data are gathered for the calibration of the prototype, including two turbidity sources, sediment and algae, including pure samples and mixed samples. Samples were measured at a different concentration from 15 mg/L to 4000 mg/L. Multiple regression models and artificial neural networks, with a training and validation phase, are compared as two alternative methods to classify the tested samples. Our results indicate that using multiple regression models, it is possible to estimate the concentration of alga with an average absolute error of 32.0 mg/L and an average relative error of 11.0%. On the other hand, it is possible to classify up to 100% of the samples in the validation phase with the artificial neural network. Thus, a novel prototype capable of distinguishing turbidity sources and two classification methodologies, which can be adapted to different node features, are proposed for the operation of the developed prototype.This work is partially funded by the Ministerio de Educacion, Cultura y Deporte through the"Ayudas para contratacion pre-doctoral de Formacion del Profesorado Universitario FPU (Convocatoria 2016)" grant number FPU16/05540 and by the Conselleria de Educacion, Cultura y Deporte through the "Subvenciones para la contratacion de personal investigador en fase postdoctoral", grant number APOSTD/2019/04.Rocher-Morant, J.; Parra-Boronat, L.; Jimenez, JM.; Lloret, J.; Basterrechea-Chertudi, DA. (2021). Development of a Low-Cost Optical Sensor to Detect Eutrophication in Irrigation Reservoirs. Sensors. 21(22):1-20. https://doi.org/10.3390/s21227637S120212
Slot-Die Process of a Sol–Gel Photocatalytic Porous Coating for Large-Area Fabrication of Functional Architectural Glass
The slot-die process is an appealing technology for the fabrication of coatings on large-area substrates. However, its application on the production of photocatalytic coatings based on sol–gel formulations remains virtually unexplored. Thus, assessing the suitable formulation of the sol and operational parameters that allow one to yield high-efficacy photocatalyst coatings is a current challenge. This work aims to analyze the transferability of titania sol formulation optimized for dip-coating processes to slot-die technology. In this sense, firstly, the sol formulation is optimized by analyzing the influence of several types of surfactants on the microstructural features and photoactivity of TiO2 coatings’ growth on glass substrates. All formulations rendered a meaningful porosity and nanoscopic anatase crystallites (11–15 nm) with optical band gap values close to the expectation (3.25–3.31 eV). Accordingly, the performance of the photocatalytic dye degradation was closely related to the porosity and crystallite size led by each titania sol, and no meaningful differences were found between the results provided by the coatings developed by dip-coating and the slot-die method, which demonstrates the capability of the latter for its application on a large-scale fabrication of photocatalytic coatings.This research was funded by the Basque Government (IT1291-19), the Spanish Ministry of Science and Innovation (MICINN project: PID2019-108028GB-C21), and the European Union’s Horizon 2020 research and innovation program (grant agreement N° 792103 SOLWARIS)
A Review on Sustainable Inks for Printed Electronics: Materials for Conductive, Dielectric and Piezoelectric Sustainable Inks
In the last decades, the demand for electronics and, therefore, electronic waste, has increased. To reduce this electronic waste and the impact of this sector on the environment, it is necessary to develop biodegradable systems using naturally produced materials with low impact on the environment or systems that can degrade in a certain period. One way to manufacture these types of systems is by using printed electronics because the inks and the substrates used are sustainable. Printed electronics involve different methods of deposition, such as screen printing or inkjet printing. Depending on the method of deposition selected, the developed inks should have different properties, such as viscosity or solid content. To produce sustainable inks, it is necessary to ensure that most of the materials used in the formulation are biobased, biodegradable, or not considered critical raw materials. In this review, different inks for inkjet printing or screen printing that are considered sustainable, and the materials that can be used to formulate them, are collected. Printed electronics need inks with different functionalities, which can be mainly classified into three groups: conductive, dielectric, or piezoelectric inks. Materials need to be selected depending on the ink’s final purpose. For example, functional materials such as carbon or biobased silver should be used to secure the conductivity of an ink, a material with dielectric properties could be used to develop a dielectric ink, or materials that present piezoelectric properties could be mixed with different binders to develop a piezoelectric ink. A good combination of all the components selected must be achieved to ensure the proper features of each ink.This publication is supported by the SUINK project funded by the European Union’s Horizon Europe research and innovation programme under Grant Agreement No. 101070112. Funded by the Basque Government ELKARTEK2021 (KK-2021/00040) and ELKARTEK2023 KK-2023/0005
Prenatal exposure to NO2 and ultrasound measures of fetal growth in the Spanish INMA cohort
__Background:__ Air pollution exposure during pregnancy has been associated with impaired fetal growth. However, few studies have measured fetal biometry longitudinally, remaining unclear as to whether there are windows of special vulnerability.
__Objective:__ The aim was to investigate the impact of nitrogen dioxide (NO2) exposure on fetal and neonatal biometry in the Spanish INMA study. Methods: Biparietal diameter (BPD), femur length (FL), abdominal circumference (AC), and estimated fetal weight (EFW) were evaluated for up to 2,478 fetuses in each trimester of pregnancy. Size at 12, 20, and 34 weeks of gestation and growth between these points, as well as anthropometry at birth, were assessed by SD scores derived using cohort-specific growth curves. Temporally adjusted land-use regression was used to estimate exposure to NO2 at home addresses for up to 2,415 fetuses. Associations were investigated by linear regression in each cohort and subsequent meta-analysis.
__Results:__ A 10-μg/m3 increase in average exposure to NO2 during weeks 0-12 was associated with reduced growth at weeks 0-12 in AC (-2.1%; 95% CI: -3.7, -0.6) and EFW (-1.6%; 95% CI: -3.0, -0.3). The same exposure was inversely associated with reduced growth at weeks 20-34 in BPD (-2.6%; 95% CI: -3.9, -1.2), AC (-1.8%; 95% CI: -3.3, -0.2), and EFW (-2.1%; 95% CI: -3.7, -0.2). A less consistent pattern of association was observed for FL. The negative association of this exposure with BPD and EFW was significantly stronger in smoking versus nonsmoking mothers.
__Conclusi
Optimisation of vancomycin exposure in neonates based on the best level of evidence.
There is no consensus regarding optimal dosing of vancomycin in term or preterm neonates. Various available dosing recommendations are based on age, kidney function and/or body weight to define a starting dose. Our objectives were (i) to develop a comprehensive population PK model of vancomycin in a large cohort of neonates and (ii) to evaluate and compare the performances of current dosing approaches with respect to target attainment, using simulations based on our model. This will serve the purpose to recommend the best dosing approaches among existing regimens in the early and later phases after treatment initiation as a complementary approach to therapeutic drug monitoring (TDM). A total 405 neonates provided 1831 vancomycin concentrations measured during routine TDM. A one-compartment model with linear elimination incorporating covariates such as age, kidney function and body weight was developed (NONMEM®). The final model was applied to simulate in our population vancomycin exposure resulting from 20 dosing guidelines identified in the literature. Proportions of patients within and above target exposure were used as a performance measure. Target attainment meant area under the curve/minimal inhibitory concentration (AUC <sub>24</sub> /MIC) ratio of 400-700 h and trough concentration of 10-20 mg/L, both on days 1 and 7. Most current vancomycin dosing regimens fail to ensure target attainment in a majority of neonates. Insufficiently dosed regimens should be avoided, especially in centers with widespread coagulase negative Staphylococci. Adding a loading dose to simple regimens is best recommended to increase the proportion of early target attainment. Complex regimens seem to marginally improve exposure. Optimisation of efficacy while minimizing toxicity of vancomycin in neonates is needed. The application of a simple dosing regimens like NNF7 or the Neofax Hi-Dose regimens, with a 25 mg/kg loading dose for severe infections, or the SmPC regimen should be recommended to ensure the highest proportion of target attainment after 24 h. TDM should then be carried out, to account for residual unexplained variability in vancomycin elimination
Analysis of the influence of microencapsulated phase change materials on the behavior of a new generation of thermo-regulating shape memory polyurethane fibers
The present work is a first approach in order to achieve thermo-sensitive and waterproof polyurethane fibers useful in the textile industry. For this, two polyurethane formulations with glass transition temperatures (Tg) close to the body temperature have been synthetized and characterized by several techniques such as Ther-mogravimetric Analysis (TGA), Differential Scanning Calorimetry (DSC), Dynamic-Mechanical Analysis (DMA) and Thermo-mechanical analysis (TMA). In this manner their thermal and shape memory behavior were determined. It was also estimated the water vapor transmission rate of both polyurethane films. Then, integration of two different microencapsulated phase change materials (PCMs), one with organic shell and another one, with an inorganic shell, was carried out by extrusion in order to achieve materials with thermo-regulating properties. Fibers for both polyurethanes, pristine or loaded with microencapsulated PCMs, were again characterized to check that the thermal and shape memory properties are maintained, and to study their capability to storage and release energy. The promising results pave the way for a new generation of thermo-regulating materials useful in numerous applications such as the textile sector.Authors would like to acknowledge the Basque Government funding within the ELKARTEK 2019 (KK-2019/00039) and ELKARTEK 2021 (KK-2021/00040) and FRONTIERS IV Prog rammes
Quantifying the Production of Fruit-Bearing Trees Using Image Processing Techniques
[EN] In recent years, the growth rate of world agricultural production and crop yields have decreased. Crop irrigation becomes essential in very dry areas and where rainfall is scarce, as in Egypt. Persimmon needs low humidity to obtain an optimal crop. This article proposes the monitoring of its performance, in order to regulate the amount of water needed for each tree at any time. In our work we present a technique that consists of obtaining images of some of the trees with fruit, which are subsequently treated, to obtain reliable harvest data. This technique allows us to have control and predictions of the harvest. Also, we present the results obtained in a first trial, through which we demonstrate the feasibility of using the system to meet the objectives set. We use 5 different trees in our experiment. Their fruit production is different (between 20 and 47kg of fruit). The correlation coefficient of the obtained regression model is 0.97.This work has been partially supported by European Union
through the ERANETMED (Euromediterranean Cooperation
through ERANET joint activities and beyond) project
ERANETMED3-227 SMARTWATIR by the Conselleria de
Educación, Cultura y Deporte with the Subvenciones para la
contratación de personal investigador en fase postdoctoral,
grant number APOSTD/2019/04, and by the Cooperativa
Agrícola Sant Bernat Coop.V.García, L.; Parra-Boronat, L.; Basterrechea-Chertudi, DA.; Jimenez, JM.; Rocher-Morant, J.; Parra-Boronat, M.; García-Navas, JL.... (2019). Quantifying the Production of Fruit-Bearing Trees Using Image Processing Techniques. IARIA XPS Press. 14-19. http://hdl.handle.net/10251/180619S141
Oral Anticoagulation and Risk of Symptomatic Hemorrhagic Transformation in Stroke Patients Treated With Mechanical Thrombectomy: Data From the Nordictus Registry
Introduction: We aimed to evaluate if prior oral anticoagulation (OAC) and its type determines a greater risk of symptomatic hemorrhagic transformation in patients with acute ischemic stroke (AIS) subjected to mechanical thrombectomy. Materials and
Methods: Consecutive patients with AIS included in the prospective reperfusion registry NORDICTUS, a network of tertiary stroke centers in Northern Spain, from January 2017 to December 2019 were included. Prior use of oral anticoagulants, baseline variables, and international normalized ratio (INR) on admission were recorded. Symptomatic intracranial hemorrhage (sICH) was the primary outcome measure. Secondary outcome was the relation between INR and sICH, and we evaluated mortality and functional outcome at 3 months by modified Rankin scale. We compared patients with and without previous OAC and also considered the type of oral anticoagulants.
Results: About 1.455 AIS patients were included, of whom 274 (19%) were on OAC, 193 (70%) on vitamin K antagonists (VKA), and 81 (30%) on direct oral anticoagulants (DOACs). Anticoagulated patients were older and had more comorbidities. Eighty-one (5.6%) developed sICH, which was more frequent in the VKA group, but not in DOAC group. OAC with VKA emerged as a predictor of sICH in a multivariate regression model (OR, 1.89 [95% CI, 1.01–3.51], p = 0.04) and was not related to INR level on admission. Prior VKA use was not associated with worse outcome in the multivariate regression model nor with mortality at 3 months.
Conclusions: OAC with VKA, but not with DOACs, was an independent predictor of sICH after mechanical thrombectomy. This excess risk was associated neither with INR value by the time thrombectomy was performed, nor with a worse functional outcome or mortality at 3 months
Rational design and direct fabrication of multi-walled hollow electrospun fibers with controllable structure and surface properties
Multi-walled hollow fibers with a novel architecture are fabricated through utilizing a direct,one-step tri-axial electrospinning process with a manufacturing methodology which does not require any post-treatments for the removal of core material for creating hollowness in the fiber structure. The hydrophilicity of both inner and outer layers’ solution needs to be dissimilar and carefully controlled for creating a two-walled/layered hollow fiber tructure
with a sharp interface. To this end, Hansen solubility parameters are used as n index of layer solution affinity hence allowing for control of diffusion across the layers and the surface porosity whereby an ideal multi-walled hollow electrospun fiber is shown to be producible by tri-axial electrospinning process. Multi-walled hollow electrospun fibers with different inner
and outer diameters and different surface morphology are successfully produced by using dissimilar material combinations for inner and outer layers (i.e., hydrophobic polymers as outer layer and hydrophilic polymer as inner layer). Upon using different material combinations for inner and outer layers, it is shown that one may control both the outer and inner diameters of the fiber. The inner layer not only acts as a barrier and thus provides an ease in the encapsulation of functional core materials of interest with different viscosities but also adds stiffness to the fiber. The structure and the surface morphology of fibers are controlled by changing applied voltage, polymer types, polymer concentration, and the evaporation rate of solvents. It is demonstrated that if the vapor pressure of the solvent for a given outer layer polymer is low, the fiber diameter decreases down to 100 nm whereas solvents with higher vapor pressure result in fibers with the outer diameter of up to 1 μm. The influence of electric field strength on the shape of Taylor cone is also monitored during the production process and the manufactured fibers are structurally investigated by relevant surface characterization techniques
DNA methylation in childhood asthma : an epigenome-wide meta-analysis
Background DNA methylation profiles associated with childhood asthma might provide novel insights into disease pathogenesis. We did an epigenome-wide association study to assess methylation profiles associated with childhood asthma. Methods We did a large-scale epigenome-wide association study (EWAS) within the Mechanisms of the Development of ALLergy (MeDALL) project. We examined epigenome-wide methylation using Illumina Infinium Human Methylation450 BeadChips (450K) in whole blood in 207 children with asthma and 610 controls at age 4-5 years, and 185 children with asthma and 546 controls at age 8 years using a cross-sectional case-control design. After identification of differentially methylated CpG sites in the discovery analysis, we did a validation study in children (4-16 years; 247 cases and 2949 controls) from six additional European cohorts and meta-analysed the results. We next investigated whether replicated CpG sites in cord blood predict later asthma in 1316 children. We subsequently investigated cell-type-specific methylation of the identified CpG sites in eosinophils and respiratory epithelial cells and their related gene-expression signatures. We studied cell-type specificity of the asthma association of the replicated CpG sites in 455 respiratory epithelial cell samples, collected by nasal brushing of 16-year-old children as well as in DNA isolated from blood eosinophils (16 with asthma, eight controls [age 2-56 years]) and compared this with whole-blood DNA samples of 74 individuals with asthma and 93 controls (age 1-79 years). Whole-blood transcriptional profiles associated with replicated CpG sites were annotated using RNA-seq data of subsets of peripheral blood mononuclear cells sorted by fluorescence-activated cell sorting. Findings 27 methylated CpG sites were identified in the discovery analysis. 14 of these CpG sites were replicated and passed genome-wide significance (p Interpretation Reduced whole-blood DNA methylation at 14 CpG sites acquired after birth was strongly associated with childhood asthma. These CpG sites and their associated transcriptional profiles indicate activation of eosinophils and cytotoxic T cells in childhood asthma. Our findings merit further investigations of the role of epigenetics in a clinical context.Peer reviewe
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