Abstract The upcoming Vera Rubin Observatory’s Legacy Survey of Space and Time (LSST) opens a new opportunity to rapidly survey the southern sky at optical wavelengths (i.e., ugrizy bands). In this ...study, we aim to test the possibility of using LSST observations to constrain the mass and velocity of different kilonova (KN) ejecta components from the observation of a combined set of light curves from afterglows of γ -ray bursts and KNe. We used a sample of simulated light curves from the aforementioned events as they would have been seen during the LSST survey to study how the choice of observing strategies impacts the parameter estimation. We found that the design of observing strategy that is the best compromise between light-curve coverage, observed filters, and reliability of the fit involves a high number of visits with long-gap pairs of about 4 hr every two nights in the same or different filters. The features of the observing strategy will allow us to recognize the different stages of the evolution of the light curve and gather observations in at least three filters.
We report an imported case of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variant P.1 detected in an asymptomatic traveler who arrived in Italy on an indirect flight from Brazil. ...This case shows the risk for introduction of SARS-CoV-2 variants from indirect flights and the need for continued SARS-CoV-2 surveillance.
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DOBA, IZUM, KILJ, NUK, ODKLJ, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Whole-body magnetic resonance imaging (WB-MRI) is currently recommended for cancer screening in adult and paediatric subjects with cancer predisposition syndromes, representing a substantial aid for ...prolonging health and survival of these subjects with a high oncological risk. Additionally, the number of studies exploring the use of WB-MRI for cancer screening in asymptomatic subjects from the general population is growing. The primary aim of this review was to analyse the acquisition protocols found in the literature, in order to identify common sequences across published studies and to discuss the need of additional ones for specific populations. The secondary aim of this review was to provide a synthesis of current recommendations regarding the use of WB-MRI for cancer screening.
ABSTRACT This work aimed to simulate the water distribution of traveler gun irrigation, working with asymmetrical wetted angles and in windy conditions. In the simulations of a sprinkler with uniform ...radial profile, the following were considered: i) wetted angles between 180 and 330°; ii) wetted angle asymmetries from 0 to 90°; iii) wind speeds from 0 to 4.5 m s-1; and iv) wind direction of 0, 45, and 90°. Christiansen uniformity coefficients (CU) were calculated for strip widths from 30 to 100% of the sprinkler wetted diameter (WD). Regardless of the wetted angle adjustment, irrigations under wind speeds of 4.5 m s-1 should be avoided and strip spacings of less than 50% WD provide high CU for wind speeds up to 3.0 m s-1. For any wind conditions, asymmetries in the wetted angle led to a reduction in CU for a wetted angle of 210°. In the range of wetted angle from 270 to 330°, asymmetric adjustments of up to 20° provided a higher CU than 80% for a wind speed of 3 m s-1 and directions diagonal and perpendicular to the travel path associated with strip spacings between 60 to 70% WD, which are the spacings recommended by manufacturers of traveler irrigation machines.
Pressure demand of a center-pivot can be controlled by variable frequency drives during irrigation system operations, leading to a rational use of electrical energy. However, numerous studies ...encountered problems due to the lack of field data to perform the simulations. The objective of this study was to simulate the reduction of the average value of the active electrical power required to drive the pumping unit of a center-pivot irrigation system by controlling the rotational speed through a frequency inverter. The simulation was conducted considering a complete rotation of the lateral line of a central pivot, installed in an area of 70-ha, in the municipality of Formiga-MG. The simulation demonstrated the possibility of reducing the active electrical power required for the pivot pump by 18%, from an average of 131 to 107 kW. For 1300 pumping hours per year, the investment's payback time would be two and four years for the highest (R$ 0.48 kWh-1) and lowest energy cost (R$ 0.32 kWh-1), respectively. Results suggest that irrigated areas by center-pivot with variations of topographic altitude require technical-economic evaluations for using frequency inverters.
AbstractThe historic Imperial Dom Pedro II Bridge, located in Bahia, Brazil, underwent a major rehabilitation program that began in 2018. All tensioned diagonals, made of puddled iron, were replaced ...with new components, made of stronger steel. This paper presents a numerical model of the Dom Pedro II Bridge capable of reproducing structural performance before and during the replacement work. Numerical results were verified by the experimental data derived from monitoring systems installed in the bridge on several occasions. The differences observed from the numerical results could be justified by the bridge’s age and maintenance condition. In general, the numerical results were fairly similar to the measured data, indicating the numerical solution could be used to assess other sequences of tensioned diagonal replacements. It was concluded that the replacement work improved the safety of the bridge, and the proposed modeling process may be suitable for other sequences of replacements, including other steel truss bridges.
We aimed to describe the relationships between the relative fat fraction (%FF), muscle-normalized diffusion-weighted (DW) image signal intensity and water apparent diffusion coefficient (ADC), sex ...and age for normal bone marrow, in the normal population. Our retrospective cohort consisted of 100 asymptomatic individuals, equally divided by sex and 10-year age groups, who underwent whole-body MRI at 1.5 T for early cancer detection. Semi-automated segmentation of global bone marrow volume was performed using the DW images and the resulting segmentation masks were projected onto the ADC and %FF maps for extraction of parameter values. Differences in the parameter values between sexes at age ranges were assessed using the Mann–Whitney and Kruskal–Wallis tests. The Spearman correlation coefficient r was used to assess the relationship of each imaging parameter with age, and of %FF with ADC and normalized DW signal intensity values. The average %FF of normal bone marrow was 65.6 ± 7.2%, while nSIb50, nSIb900 and ADC were 1.7 ± 0.5, 3.2 ± 0.9 and 422 ± 67 μm2/s, respectively. The bone marrow %FF values increased with age in both sexes (r = 0.63 and r = 0.64, respectively, p < 0.001). Values of nSIb50 and nSIb900 were higher in younger women compared to men of the same age groups (p < 0.017), but this difference decreased with age. In our cohort of asymptomatic individuals, the values of bone marrow relative %FF, normalized DW image signal intensity and ADC indicate higher cellularity in premenopausal women, with increasing bone marrow fat with aging in both sexes.
ABSTRACT Climate change impacts need to be considered in water resource planning. This work aims to study of the impacts climate change on Lavrinha headwater watershed, located in the Mantiqueira ...Range, southeastern Brazil. The impacts from climate change (RCP 8.5 scenario) in the Lavrinha watershed runoff were analyzed based on the "Distributed Hydrology Soil Vegetation Model" (DHSVM), forced with the climate simulated for this future climate change scenario. These simulations, in turn, were generated by the Eta regional climate model coupled to Global Climate Model (GCM) HadGEM2-ES for the 2011-2040, 2041-2070 and 2071-2099 periods. The results of this study showed that the runoff is very sensitive to rising temperatures and reduced precipitation, both projected for the RCP 8.5 scenario. The hydrological simulation projected a reduction in the monthly streamflow between 20 and 77% over the twenty-first century (2011-2099), corresponding to drastic reductions in the runoff behavior and consequently in the water production capacity of the region.
RESUMO O impacto das mudanças climáticas precisa ser considerado no planejamento dos recursos hídricos. Este trabalho tem por objetivo o estudo dos impactos das mudanças climáticas na bacia de cabeceira Lavrinha, localizada na Serra da Mantiqueira, Sudeste do Brasil. Os impactos oriundos das mudanças climáticas (cenário RCP 8.5) no escoamento da bacia hidrográfica Lavrinha foram analisados com base no modelo "Distributed Hydrology Soil Vegetation Model" (DHSVM), forçado com as condições climáticas simuladas para este cenário futuro de mudanças climáticas. Estas simulações, por sua vez, foram geradas pelo modelo climático regional Eta acoplado ao Modelo Climático Global (MCG) HadGEM2-ES, nos períodos de 2011-2040, 2041-2070 e 2071-2099. Os resultados deste estudo mostraram que a vazão é bastante sensível ao aumento da temperatura e diminuição da precipitação, ambos projetados para o cenário RCP 8.5. A simulação hidrológica projetou uma redução na vazão mensal entre 20 e 77% ao longo do século XXI (2011 a 2099), correspondendo a reduções drásticas no escoamento e, consequentemente, na capacidade de produção de água da região.
Pumping systems are the largest energy consumers in center pivot irrigation systems. One action to reduce energy consumption is to adjust the pumping pressure to that which is strictly needed by ...using variable speed drives (VSDs). The objective of this study was to determine the feasibility of including VSDs in pumping systems that feed center pivot systems operating in an area with variable topography. The VSPM (Variable Speed Pivot Model) was developed to perform hydraulic and energy analyses of center pivot systems using the EPANET hydraulics engine. This tool is able to determine the elevation of each tower for each position of the center pivot using any type of digital elevation model. It is also capable of simulating, in an accurate manner, the performance of the center pivot controlled with a VSD. The tool was applied to a real case study, located in Albacete, Spain. The results show a reduction in energy consumption of 12.2%, with specific energy consumptions of 0.214 and 0.244 kWh m−3 of distributed water obtained for the variable speed and fixed speed of the pumping station, respectively. The results also show that for an irrigation season, to meet the water requirements of the maize crop in the region of the study (627 mm), an average annual savings of 14,107.35 kWh was obtained, which resulted in an economic savings of 2821.47€.
We report here an imported case of SARS-CoV-2 variant of concern B.1.1.351 (also known as 20H/501Y.V2 or "South African variant" or VOC 202012/02) in a 66-years old symptomatic male who returned from ...Malawi to Italy.
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