Thin films of lithium spinel ferrite, LiFeO, have attracted much scientific attention because of their potential for efficient excitation, the manipulation and propagation of spin currents due to their insulating character, high-saturation magnetization, and Curie temperature, as well as their ultra-low damping value. In addition, LiFeO is currently one of the most interesting materials in terms of developing spintronic devices based on the ionic control of magnetism, for which it is crucial to control the lithium's atomic content. In this work, we demonstrate that dual ion beam sputtering is a suitable technique to tailor the lithium content of thin films of lithium ferrite (LFO) by using the different energies of the assisting ion beam formed by Ar and O ions during the growth process.
View Article and Find Full Text PDFOver two decades, the area with sugarcane has more than doubled, from 4.8 million hectares in 2000 to 10 million in 2018, in Brazil. São Paulo State is mostly responsible for the sugarcane production in the country, accounting for 51% of the national production.
View Article and Find Full Text PDFWater Environ Res
June 2024
Wastewater containing tetrabromobisphenol A (TBBPA), a commonly used flame retardant found in wastewater, can present significant toxic effects on biota, yet its impact on tropical freshwater environments is not well understood. This study explores the effectiveness of two independent anaerobic treatment systems, the acidogenic reactor (AR) and the methanogenic reactor (MR), for the ecotoxicity reduction of TBBPA-rich wastewater in four tropical freshwater species. Despite presenting good physicochemical performance and reduced toxicity of the influent for most species, AR and MR treatments remain acute and chronic toxicity.
View Article and Find Full Text PDFPhotocatalytic nitrogen fixation to ammonia and nitrates holds great promise as a sustainable route powered by solar energy and fed with renewable energy resources (N and HO). This technology is currently under deep investigation to overcome the limited efficiency of the process. The rational design of efficient and robust photocatalysts is crucial to boost the photocatalytic performance.
View Article and Find Full Text PDFMagnetosomes are magnetite nanoparticles biosynthesized by magnetotactic bacteria. Given their potential clinical applications for the diagnosis and treatment of cancer, it is essential to understand what becomes of them once they are within the body. With this aim, here we have followed the intracellular long-term fate of magnetosomes in two cell types: cancer cells (A549 cell line), because they are the actual target for the therapeutic activity of the magnetosomes, and macrophages (RAW 264.
View Article and Find Full Text PDFAquatic worms are considered a suitable group to evaluate the effects of contaminants on the environment, although one of the main challenges is to use the species of local occurrence. Recently, Pristina longiseta was suggested to be used in acute bioassays. In this context, this study aimed to establish a chronic exposure for ecotoxicological bioassays using the cosmopolitan species of occurrence in Brazilian freshwater P.
View Article and Find Full Text PDFDeep-UV (180-280 nm) phosphors have attracted tremendous interest in tri-band-based white light-emitting diode (LED) technology, bio- and photochemistry, as well as various medical fields. However, the application of many UV-emitting materials has been hindered due to their poor thermal or chemical stability, complex synthesis, and environmental harmfulness. A particular concern is posed by the utilization of rare earths affected by rising price and depletion of natural resources.
View Article and Find Full Text PDFACS Appl Mater Interfaces
July 2022
The present study proposes a laser irradiation method to superficially reduce BiVO photoelectrodes and boost their water oxidation reaction performance. The origin of this enhanced performance toward oxygen evolution reaction (OER) was studied using a combination of a suite of structural, chemical, and mechanistic advanced characterization techniques including X-ray photoelectron (XPS), X-ray absorption spectroscopy (XAS), electrochemical impedance spectroscopy (EIS), and transient absorption spectroscopy (TAS), among others. We found that the reduction of the material is localized at the surface of the sample and that this effect creates effective n-type doping and a shift to more favorable energy band positions toward water oxidation.
View Article and Find Full Text PDFBackground: A drug and disease assessment model was used to evaluate the impact of different treatment regimens on intravitreal ranibizumab, bevacizumab, aflibercept, and brolucizumab concentrations and the proportion of free vascular endothelial growth factor (VEGF) to total VEGF.
Methods: A time-dependent mathematical model using Wolfram Mathematica software was used. The pharmacokinetic and pharmacodynamic data for anti-VEGFs were obtained from published reports.
The use of agrochemicals in agriculture may impact aquatic ecosystems, particularly influencing the stream insect communities. Among aquatic insects, the family Chironomidae is the most abundant and species-diverse insect group found in freshwater ecosystems. However, in the southern hemisphere, studies with Chironomidae are still sparse, compared to Europe and North America.
View Article and Find Full Text PDFThe aim of this paper was recording the occurrence of the species Lumbriculus variegatus (Müller, 1774) (Oligochaeta, Lumbriculidae) in lotic systems of the State of São Paulo. Specimens were collected in Sapucaí River, located in Campos do Jordão State Park. The mapping of geographical distribution of this species is of interest to public health since L.
View Article and Find Full Text PDFEcotoxicological bioassays have been widely applied to evaluate the toxicity of substances in standardized test organisms. Nevertheless, the main challenge for researchers is the use of native species to express the effects of pollutants on aquatic biota. Thirty years ago, Smith and collaborators evaluate the possible use of Pristina longiseta (as Pristina leidyi) in acute toxicity test, developing some experiments using cadmium and vanadium as toxicants.
View Article and Find Full Text PDFTransparent oxyfluoride glass-ceramics containing NaGdF nanocrystals were prepared by melt-quenching and doped with Er (0.5 mol%) and different amounts of Yb (0-2 mol%). The selected dopant concentration the crystallization thermal treatments were chosen to obtain the most efficient visible up-conversion emissions, together with near infrared emissions.
View Article and Find Full Text PDFA few patients in advanced or end-stage (stage D or NYHA functional class IV) heart failure are transplant or ventricular assist device eligible. Particularly for the non-operative patients (elderly or with significant comorbidities), intravenous palliative inotropes can be utilized for symptom control, for functional class and quality of life improvement. The authors report evidence-based medicine data about palliative inotrope therapy in advanced heart failure patients and they suggest a possible multidisciplinary approach in order to guarantee the best care to these patients.
View Article and Find Full Text PDFTreatment of patients with heart failure is based on drugs, cardiac surgery and implantable cardiac devices to prevent sudden cardiac death (implantable cardioverter-defibrillator [ICD]), to reverse left ventricular dysfunction associated with left bundle branch block (cardiac resynchronization therapy) or mechanical circulatory support in more advanced phases of heart failure (left ventricular assist devices [LVAD]).During the follow-up, patients may die from progression of their underlying heart disease or from non-arrhythmic causes, such as malignancies, multi-organ failure, stroke, etc., without benefits by implanted devices.
View Article and Find Full Text PDFEnviron Monit Assess
January 2020
Increasing concerns have been raised about the toxicity of mercury (Hg) to humans, especially for those that consume a great amount of fish. High Hg concentrations have previously been measured in Amazonian waterbodies, both resulting from natural and anthropogenic sources. However, few studies have been conducted so far in Amazonian lakes that are fished by local populations.
View Article and Find Full Text PDFNovel glass-ceramic optical fibers containing NaLuF nanocrystals doped with 0.5ErF and 2YbF (mol%) have been prepared by the rod-in-tube method and controlled crystallization. NaLuF nanocrystals with a size around 20 nm are obtained after heat treatment at 600 °C.
View Article and Find Full Text PDFIn ecotoxicological assays, previously selected and standardized organism tests are exposed to an environmental sample. Some species of the Chironomus genus have been extensively used in ecotoxicological assays. Among these, Chironomus tentans is usually utilized in the USA and Chironomus sancticaroli in Brazil.
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