This paper presents a new procedure to optimize the geometric parameters of a n-type coaxial HPGe detector. It is based on a statistical technique called “Design of Experiments” (DoE). This technique ...aims to identify the most influential parameters and to determine the optimal configuration. In this work, The effects of each parameter on the detector responses have been investigated by a fractional factorial design. Only the most influential factors contributing to the detector response have been selected. Precise modeling of these factors was then performed using a full factorial design. Based on the results obtained from this design, the full energy peak efficiencies according to the geometric parameters were modeled by a multiple-linear regression. These models have been statistically validated by analysis of variance (ANOVA). The optimal combination of the geometric parameters has been identified using the desirability function approach, which is a useful tool to optimize multi-response problems. A verification test was performed to validate the results obtained. It was observed that the relative deviation found between experimental and simulated values was less than 5%.
•Optimization of geometrical dimensions of an HPGe detector.•Application of Monte Carlo simulation and “Design of Experiments” technique.•Investigating influence of each detector parameter on the FEPE.•Achieving good agreement between the measured and the simulated results.
The Toluca Valley is located on the high plains of Mexico, where there are significant industrial zones and large populations. Water needs are almost exclusively met by groundwater, which has brought ...about intense exploitation of the aquifer and indication of some contamination. The present study investigates the effect of urbanization, related to industrialization of the region, on groundwater in the central portion of the Toluca Valley aquifer—a zone with high population density and where the largest industrial park is located. A general decline in the groundwater level has been found over the years, at a rate of as much as 2.5 m/year. The appearance of a large drawdown cone was identified, indicating changes in the direction of groundwater flow. Also identified was the presence of several ground fissures, the location of which coincided with the drawdown cone. In hydrochemical terms, the water type is sodium-magnesium bicarbonate and this characteristic has not changed over time, although it has been possible to detect the presence of larger quantities of sulfates (up to 117 mg/L) and nitrates (up to 47 mg/L) in recent years, likely associated with contamination from industrial and urban wastewater. Factor analysis made it possible to identify ions that would characterize natural processes involving the acquisition of salts (HCO₃ ⁻, Na⁺, Mg²⁺, and Si), as well as anthropic activities (SO₄ ²⁻, NO₃ ⁻, Cl⁻, Ca²⁺, and K⁺).
This paper studies the uranium content and uranium isotopic disequilibria as a tool to identify hydrogeochemical processes from 52 groundwater samples in the province of Granada (Betic Cordillera, ...southeastern Spain). According to the geological complexity of the zone, three groups of samples have been considered. In Group 1 (thermal waters; longest residence time), the average uranium content was 2.63 ± 0.16 μg/L, and 234U/238U activity ratios (AR) were the highest of all samples, averaging 1.92 ± 0.30. In Group 2 (mainly springs from carbonate aquifers; intermediate residence time), dissolved uranium presented an average value of 1.34 ± 0.13 μg/L, while AR average value was 1.38 ± 0.25. Group 3 comes from pumping wells in a highly anthropized alluvial aquifer. In this group, where the residence time of the groundwater is the shortest of the three, average uranium content was 5.28 ± 0.26 μg/L, and average AR is the lowest (1.17 ± 0.12). In addition, the high dissolved uranium value and the low AR brought to light the contribution of fertilizers (Group 3). In the three groups, 235U/238U activity ratios were similar to the natural value of 0.046. Therefore, 235U detected in the samples comes from natural sources. This study is completed with the determination of major ions and physicochemical parameters in the groundwater samples and the statistical analysis of the data by using the Principal Component Analysis. This calculation indicates the correlation between uranium isotopes and bicarbonate and nitrate anions.
•Natural uranium isotopic ratios have been calculated and used as a prospecting tool in hydrogeochemical processes in groundwater samples.•Anthropogenic contribution to the presence of uranium has been found.•234U/238U activity ratio has demonstrated to be a key factor to distinguish different geological environments.•A statistical study has been performed and some chemical processes that take place in water have been remarked.
Golf courses represent an agricultural activity wherein grass is intensively cultivated using large quantities of fertilizers. In the present study, nitrogen and phosphorus leaching was analyzed over ...two years in an experimental green under actual field conditions. The green contained four plots with distinct amendments (P1: hydrogel + peat, P2: peat, P3: hydrogel, and P4: no amendment). The applied doses of nitrogen ranged from 5 to 103 kg/ha and of phosphorus from 9 to 31 kg/ha. The irrigation level varied as a function of the rainfall regime and the water requirements of grass; overall water intake varied from 1550 to 2080 mm/year. Daily, leached water volume was calculated, and samples were taken for chemical analysis. Nitrogen and phosphorus mass balances were calculated for different periods based on the collected data.
The plot amended with peat and hydrogel (P1) had reduced water flow; the percentage of drainage water varied from 8.4 to 29%. As a result, the dissolution and leaching of nitrogen (N) and phosphorus (P) were the lowest in comparison to the other plots. According to the calculated mass balances, the lowest leaching values were also recorded in this plot (P1), ranging from 0.5 to 6.3% for N and from 0.8 to 20.9% for P. The plot without amendment (P4) drained the most water (25.9–44.8%) and leached the highest quantities of N and P, ranging from 9.1–45.7%, and 6–35.9%, respectively. The use of double amendments (hydrogel and peat) therefore represented optimal operating conditions for the green. Moreover, a relationship was found between increasing rates of fertilization and increasing percentages of N and P leaching as well as between higher irrigation levels and greater leaching.
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•Hydrogel amendment reduces N and P leaching as well as water percolation.•Peat amendment does not impact the percentage of leached N.•The largest amount of N and P leached is detected in the plot no amendment.•A larger irrigation rate (>10 mm) favors leaching of N and P, and water percolation.
In the present study, microplastics (MPs) and metal concentrations were studied in the widely consumed tilapia (Oreochromis niloticus) fishes (n = 15) collected from a metropolitan reservoir of the ...Atoyac River basin, Mexico. Nearly 139 fibers were extracted from the gastrointestinal tracts and assessed using optical microscopy to evaluate their physical characteristics. The colour distribution of the fibers was mainly black (40%), blue (19%), red and white (14%). SEM images represented the surface morphology, while the elemental composition of the fibers was studied using EDX spectra. Polymer characterization using μFTIR aided in confirming the fibers as plastics (polyamide, polyester, and synthetic cellulose) and non-plastics (natural cellulose). Henceforth, ∼33% of the fibers, provisionally thought to be plastics, were natural fibers. The total metal concentrations were higher in the liver (259.24 mg kg−1) than the muscle (122.56 mg kg−1) due to diverse metabolic functions in the hepatic tissues. Human health risk assessment in terms of Hazard Index (HI) presented Pb and Zn values above unity in both adults and children, prompting regulatory measures. Statistical tests between MPs and fish biometry did not present any substantial correlations. The present study also affirmed that the presence of MPs and metals in fishes of a highly contaminated region is not only governed by their bioavailabilities, but also on the physiological characteristics of the individual organism.
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•Microplastic prevalence of 53.67% was found in Freshwater Tilapia from a metropolitan reservoir.•HI values > 1 for Pb and Zn in adults and children prompt remedial actions.•No significant correlations between MPs and fish biometry/metal levels.
•Parameters of generator and some regulators have already been estimated with UKF.•This paper is the first one in estimating the case of a fully regulated generator.•The method uses only external ...measurements to ease industrial application.•Convergence is achieved with an especific reformulation of parameters.
This paper presents a parameter estimation technique for generation sets including the synchronous machine-turbine pair, along with the customary controllers: speed governor, automatic voltage regulator and power system stabilizer. The proposed technique is based on the Unscented Kalman Filter for the joint estimation of the system dynamic state and a modified set of parameters from which the actual model parameters and constants can be computed. To the authors’ knowledge, this work is the first attempt to estimate such a full set of dynamic state variables and parameters, using just external measurements taken at the generator terminal bus.
The AErosol RObotic NETwork (AERONET) estimates of instantaneous solar broadband fluxes (F) at surface have been validated through comparison with ground‐based measurements of broadband fluxes at ...Mauna Loa Observatory (MLO) and by the Baseline Surface Radiation (BSRN) and the Solar Radiation Networks (SolRad‐Net) during the period 1999–2005 and 1999–2006, respectively. The uncertainties in the calculated aerosol radiative forcing (ΔF) and radiative forcing efficiency (ΔFeff) at the bottom of the atmosphere were also assessed. The stations have been selected attempting to cover different aerosols influences and hence radiative properties: urban‐industrial, biomass burning, mineral dust, background continental, maritime aerosols and free troposphere. The AERONET solar downward fluxes at surface agree with ground‐based measurements in all situations, with a correlation higher than 99% whereas the relation of observed to modeled fluxes ranges from 0.98 to 1.02. Globally an overestimation of 9 ± 12 Wm−2 of solar measurements was found, whereas for MLO (clear atmosphere) the differences decrease noticeably up to 2 ± 10 Wm−2. The highest dispersion between AERONET estimates and measurements was observed in locations dominated by mineral dust and mixed aerosols types. In these locations, the F and ΔF uncertainties have shown a modest increase of the differences for high aerosol load, contrary to ΔFeff which are strongly affected by low aerosol load. Overall the discrepancies clustered within 9 ± 12 Wm−2 for ΔF and 28 ± 30 Wm−2 per unit of aerosol optical depth, τ, at 0.55 μm for ΔFeff, where the latter is given for τ(0.44 μm) ≥ 0.4. The error distributions have not shown any significant tendency with other aerosol radiative properties as well as size and shape particles.
Worldwide, measures are being implemented to eradicate hepatitis B (HBV) and C (HCV) viruses, which can be transmitted from the mother during childbirth. This study aims to determine the prevalence ...of HBV and HCV in pregnant women in Spain, focusing on country of origin, epidemiological factors and risk of vertical transmission (VT).
Multicentre open-cohort study performed during 2015. HBV prevalence was determined in 21870 pregnant women and HCV prevalence in 7659 pregnant women. Epidemiological and risk factors for VT were analysed in positive women and differences between HBV and HCV cases were studied.
HBV prevalence was 0.42% (91/21870) and HCV prevalence was 0.26% (20/7659). Of the women with HBV, 65.7% (44/67) were migrants. The HBV transmission route to the mother was unknown in 40.3% of cases (27/67) and VT in 31.3% (21/67). Among risk factors for VT, 67.7% (42/62) of the women had viraemia and 14.5% (9/62) tested HBeAg-positive. All of the neonates born to HBV-positive mothers received immunoprophylaxis, and none contracted infection by VT. In 80% (16/20) of the women with HCV, the transmission route was parenteral, and nine were intravenous drug users. Viraemia was present in 40% (8/20) of the women and 10% (2/20) were HIV-coinfected. No children were infected. Women with HCV were less likely than women with HBV to breastfeed their child (65% vs. 86%).
The prevalences obtained in our study of pregnant women are lower than those previously documented for the general population. Among the women with HBV, the majority were migrants and had a maternal family history of infection, while among those with HCV, the most common factor was intravenous drug use. Despite the risk factors observed for VT, none of the children were infected. Proper immunoprophylaxis is essential to prevent VT in children born to HBV-positive women.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
To evaluate with an animal model of osteoarthritis (New Zealand rabbits) the effectiveness of treatment with active viscosupplements (hyaluronic acid loaded with nanoparticles (NPs) that encapsulate ...anti-inflammatory compounds or drugs.
Experimental study composed of 5 groups of rabbits in which section of the anterior cruciate ligament and resection of the internal meniscus were performed to trigger degenerative changes and use it as a model of osteoarthritis. The groups were divided into osteoarthrosis without treatment (I), treatment with commercial hyaluronic acid (HA) (II), treatment with HA with empty nanoparticles (III), treatment with HA with nanoparticles encapsulating dexamethasone (IV) and treatment with HA with nanoparticles that encapsulate curcumin (V). In groups II to V, the infiltration of the corresponding compound was carried out spaced one week apart. Macroscopic histological analysis was performed using a scale based on the Outerbridge classification for osteoarthritis.
We observed that this osteoarthritis model is reproducible and degenerative changes similar to those found in humans are observed. The groups that were infiltrated with hyaluronic acid with curcumin-loaded nanoparticles (V), followed by the dexamethasone group (IV) presented macroscopically less fibrillation, exposure of subchondral bone and sclerosis (better score on the scale) than the control groups (I) (osteoarthritis without treatment), group (II) treated with commercial hyaluronic acid and hyaluronic acid with nanoparticles without drug (III).
The use of active viscosupplements could have an additional effect to conventional hyaluronic acid treatment due to its antioxidant and anti-inflammatory effect. The most promising group was hyaluronic acid with nanoparticles that encapsulate curcumin and the second group was the one that encapsulates dexamethasone.
Background and importanceHepatitis C virus (HCV) is one of the leading causes of progressive liver damage, cirrhosis and hepatocellular carcinoma. The emergence of pangenotypic regimens presents new ...opportunities for HCV treatments, regardless of genotype, minimising the need for virological testing services.Aim and objectivesTo describe the use of different pangenotypic treatments in HCV patients to evaluate efficacy and safety.Material and methodsObservational and retrospective study in all adult HCV patients who received treatment with pangenotypic treatments between January and December 2020 in a regional hospital of 300 beds. Hospital pharmacist-dispensed treatment monitoring adherence and tolerance. Data collected were age, sex, genotype, degree of fibrosis, type of patients (naïve, relapse or non-respondent), HCV treatment, treatment duration, basal viral load (VL), VL at 12 weeks after treatment completion and adverse reactions. As an indicator of efficacy, sustained viral response (SVR) was used.Results42 patients (76.9% men) were analysed. Median age 50.8 (range 27–79) years. A patient (2.4%) had genotype 1a, 2 (4.8%) had genotype 1b, 5 (11.9%) had genotype 2, 1 (2.4%) had genotype 3, 3 (7.1%) had genotype 4, 1 (2.4%) had genotype 5 and the genotype was not determined in 29 patients (69%). Regarding the degree of fibrosis, 17 patients (40.5%) were F0-F1, 6 (14.3%) were F2, 5 (11.9%) were F3 and 14 (33.3%) were F4. 34 (80.9%) were naïve patients, 5 (11.9%) failed prior treatment based on interferon and 3 (7.1%) were non-responders to treatment with direct-acting antivirals (DAA). 15 patients (35.7%) were treated with glecaprevir/pibrentasvir for 8 weeks, 24 patients (57.1%) with sofosbuvir/velpatasvir for 12 weeks and 3 (7.1%) with sofosbuvir/velpatasvir/voxilaprevir for 12 weeks. Median baseline VL was 3 125 159.6 IU/mL (range 3130–55 800 000), with 22 patients (52.4%) having >800 000 UI/mL. SVR was achieved in 38 patients (90.5%). VL was not determined in 3 patients. Regarding safety, 6 patients (14.3%) suffered at least one adverse reaction: headache (3), fatigue (2), gastrointestinal discomfort (2) and insomnia (1).Conclusion and relevancePangenotypic regimens probably represent the latest stage of development of treatment for chronic hepatitis C, and they have extremely high efficacy regardless of genotype, subtype, treatment history, or fibrosis status. They are well-tolerated drugs with a good safety profile.References and/or acknowledgementsConflict of interestNo conflict of interest
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