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The Standard Cosmological Model has experienced tremendous success at reproducing observational data by assuming a universe dominated by a cosmological constant and dark matter in a flat geometry. However, several studies, based on local measurements, indicate that the universe is expanding too fast, in disagreement with the Cosmic Microwave Background. Taking into account combined data from CMB, Baryon Acoustic Oscillation, and type Ia Supernovae, we show that if the mechanism behind the production of dark matter particles has at least a small non-thermal origin, one can induce larger values of the Hubble rate H 0 , within the Λ CDM, to alleviate the trouble with H 0 . In the presence of non-standard cosmology, however, we can fully reconcile CMB and local measurements and reach H 0 = 70 –74 km s - 1 Mpc - 1 . [ABSTRACT FROM AUTHOR]

Self-sustainable membranes were synthesized based on a solid polymer electrolyte, with sodium alginate (NaAlg) as host matrice and lithium perchlorate ( LiClO 4 ) as doping agent. Next, they were characterized by X-ray diffraction, Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy, thermogravimetry (TG/DTG) and differential exploratory calorimetry (DSC). The diffractograms showed that the amorphous behavior of the pure sodium alginate membrane predominates in membranes with salt. The FTIR spectra revealed no band displacement; however, physical interactions between the polymer chains and salt ions are confirmed by the variation in the area of the two bands. The morphological images demonstrated that all the membranes, except for AlgL1, exhibited homogeneous surfaces with clusters of different shapes and sizes, showing the presence of salt in the polymer matrice. The TG/DTG curves indicated that salt did not interfere in polymer decomposition; however, salt decomposes at lower temperatures as its concentration increases in the electrolyte. Based on TG/DTG data, a kinetic study was conducted of the thermal decomposition of the membranes using the Coats—Redfern and Horowitz–Metzger methods, suggesting first-order kinetics, thereby obtaining the pre-exponential factor (A) and the thermal activation parameters. The DSC curves revealed that two exothermal events occur, the first related to polymer decomposition and the second to salt decomposition. [ABSTRACT FROM AUTHOR]

Cork-modified graphite electrodes were used to develop a simple and selective sensor for the simultaneous determination of paracetamol (PAR) and caffeine (CAF). The sensor was fabricated on raw cork (RAC) and regranulated cork (RGC). When modified with RAC, graphite (GrRAC) displayed an improvement in voltammetric responses for PAR and CAF compared to the sensor modified with RGC (GrRGC). By applying differential pulse voltammetry (DPV) in an acidic medium with the GrRAC sensor, it was possible to simultaneously determine the concentrations of PAR and CAR (ranging from 0 to 50 μM), with limits of detection of 8.36 and 12.25 μM, respectively. The fabricated electrochemical sensor was able to individually and simultaneously detect PAR and CAF in different samples, confirming that the proposed sensor is a practical and effective tool for determining these pharmaceuticals in dosage forms and synthetic urine. Moreover, GrRAC and GrRGC possessed several advantages compared with current methods of detection, including very low detection limits, high sensitivity, long-term stability, and excellent reproducibility. [ABSTRACT FROM AUTHOR]

Correction to: I Scientific Reports i https://doi.org/10.1038/s41598-022-24608-5, published online 22 November 2022 In the original version of this Article the author R. Silva was incorrectly affiliated with 'Instituto de Física Gleb Wataghin, Universidade Estadual de Campinas, Campinas, SP, 13083-859, Brasil' and 'International Institute of Physics, Universidade Federal do Rio Grande do Norte, Natal, RN, 59078-970, Brasil'. Departamento de Física, Universidade Federal do Rio Grande do Norte, Natal, RN, 59078-970, Brasil. [Extracted from the article]