Review of experimental and theoretical research on positronium ions and molecules

 In this review we discuss the status of the research for the three-body positronium negative ion ($$\hbox {Ps}^{-}$$, $$e^{-}e^{+}e^{-}$$) and the four-body positronium molecule ($$\hbox {Ps}_{{2}}$$, $$e^{-}e^{+}e^{-}e^{+}$$) from both theoretical and experimental points of view. Experimental results are included to compare with theoretical predictions. J. A. Wheeler, during the 1940s, proved that $$\hbox {Ps}^{-}$$ has a stable bound state and he also speculated that larger systems such as $$\hbox {Ps}_{{2}}$$ can exist. There have been several theoretical works starting from the 1940s about the properties of $$\hbox {Ps}^{-}$$ and $$\hbox {Ps}_{{2}}$$. However, experimental observation of such exotic systems proved to be challenging. Thus, $$\hbox {Ps}^{-}$$ was first observed in 1981 and Ps$$_{2}$$ was only seen in 2007. During recent decades, there have been major advances in determining the properties of the positronium negative ion and the positronium molecule. These studies shed light on the properties of such exotic systems and allow us to better understand and test the theory of quantum electrodynamics (QED)

Electronic and optical properties of CuGaS

In this work we study the electronic and optical properties of fully relaxed CuGaS2 nanowires using the pseudo-potential density functional method. In our calculations we have investigated nanowires with two shapes of hexagonal and triangular with their corresponding diameters in the order of 8 to 15 Å in (1–10) growth direction. For CuGaS2 bulk, the geometrical parameters such as anion displacement and equilibrium lattice constant agree well with other theoretical and experimental results. We have shown that for the CuGaS2 nanowires, there is an important contraction of the Cu-S and Ga-S bond lengths in the wires of 2.1% and 1.24% of the bulk value. In addition, in this manuscript the electronic properties such as band structures and atom-projected density of states have been examined. Our results show that while the nanowire diameter increases, the band gap decreases. From partial density of states we found that the greatest valence bands involve atoms which are placed at the surface. The optical constants, the dielectric function, reflectivity, refractive index and absorption of the nanowires have been analyzed. The results show that compared to the CuGaS2 bulk, the corresponding peaks of dielectric functions of CuGaS2 nanowires are blue-shifted. The calculations reveal that the dielectric functions of the nanowires augment while the nanowires’ size increases. It is also found that the peaks related to optical parameters of nanowires are affected by the diameter of the nanowire

Administration of finerenone in chronic kidney disease

Spironolactone is a first-generation and non-selective mineralocorticoid receptor antagonist (MRA). It is extensively well-studied and recommended due to increased accessibility for patients. Unfortunately, it is often discontinued in several cases due to its association with hyperkalemia. The apparent benefit of eplerenone over spironolactone is its mineralocorticoid receptor (MR) selectivity. However, it is also characterized by low-potency and higher cost compared to spironolactone. The high adverse-effect profile of spironolactone and eplerenone has led to the innovation of novel medications such as non-steroidal MRAs. Among these medications, finerenone is the most advanced agent. Finerenone is associated with decreased proteinuria, reduced risk of hyperkalemia and increased preservation of renal function with comparable benefit in heart failure compared to selective and nonselective MRAs. The nonsteroidal structure of finerenone affects mineralocorticoid receptor binding, lipophilicity and polarity which have potent effects on distribution, the degree of attachment to blood proteins, transportation, and tissue diffusion