Subthreshold nanosecond laser therapy for chronic central serous chorioretinopathy: A prospective study.

Purpose: To investigate the morphologic and functional outcomes of nanosecond subthreshold (ST) laser treatment for patients with chronic central serous chorioretinopathy (CSC).

Methods: In this prospective study, 44 patients were treated with the ST nanosecond laser with a follow-up period of 12 months. All target variables were measured at 1, 3, 6 and 12 months after the first laser treatment.

Macular vascularisation changes analysed using OCT angiography after successful rhegmatogenous retinal detachment repair.

Aim: To analyse the macular vascularisation changes analysed using optical coherence tomography angiography (OCTA) after successful rhegmatogenous retinal detachment (RRD) repair by comparing gas silicone oil and macula-on macula-off.

Methods: This retrospective data collection included 77 eyes with RRD that underwent pars plana vitrectomy (PPV) and gas or silicone oil tamponade. We performed an OCTA during the postoperative control between 6 and 24mo after the last surgery and evaluated the main parameters measured by OCTA: foveal avascular zone (FAZ) and parafoveolar vascular density (PVD) in the superficial capillary plexus.

Interconversion of Specific and Equivalent Conductivity of Ions in Electrolyte Solution: Effects of High Ionic Valence and Temperature.

In a recent article (Fraenkel, D. , , 138957), an argument was made and advanced that the derivation of the equivalent conductivity of ionic solutions, Λ, directly from the specific conductivity, , is correct only for symmetric strong electrolytes; for asymmetric electrolytes, a scientifically more sound way of deriving Λ from is through the ionic conductivities, i.e.

Tomographically normal partner eye in very asymmetrical corneal ectasia: biomechanical analysis.

Purpose: To point out the biomechanical changes of the topographically and tomographically normal partner eye (NPE) in patients with very asymmetrical corneal ectasia.

Setting: Department of Ophthalmology, Saarland University Medical Center in Homburg/Saar, Germany.

Design: Retrospective study.

Eplerenone for treatment of chronic central serous chorioretinopathy.

Purpose: To assess the morphological and functional outcome of oral eplerenone for treatment of patients with chronic central serous chorioretinopathy (CSC) in a real life experience.

Patients And Methods: In this retrospective study, we reviewed the clinical files of 30 patients with chronic CSC. All patients were treated with eplerenone for a period of 6 weeks or 3 months depending on the clinical response.

An improved theory of the electric conductance of ionic solutions based on the concept of the ion-atmosphere's smaller-ion shell.

Although the electric conductivity of ionic solutions is of great importance in science and technology, complete understanding of the physical factors and principles underlying ion and charge transport in solution has so far been missing. The Debye-Hückel-Onsager (DHO) theory of the equivalent ionic conductivity (λi for single ion i, Λ for a binary electrolyte) is a limiting law of only a few electrolyte valence families, and its extension to solution of finite concentration has not been entirely successful; at most, it has led to semiempirical expressions of λi or Λ vs. concentration (c), incorporating adjustable parameters of no clear physical meaning.

Reply to "Comment on 'Negative Deviations from the Debye-Hückel Limiting Law for High-Charge Polyvalent Electrolytes: Are They Real?' ".

In their "Comment on 'Negative Deviations from the Debye-Hückel Limiting Law for High-Charge Polyvalent Electrolytes: Are They Real?' " Biver and Malatesta, citing my respective paper, argue that my analysis of experimental data of their group is wrong and so is my conclusion that negative deviations observed by them are not physically real. Here I rebut their arguments and explain why their rejection of my work is unjustified, and why those authors do not in any way prove me wrong. The core of my study and conclusion remains intact: Negative deviations in the case of high-charge electrolytes with | z z| > 3 do not always happen, and so far, such observed deviations are not convincingly supported by theory.

Negative Deviations from the Debye-Hückel Limiting Law for High-Charge Polyvalent Electrolytes: Are They Real?

In the past few decades, electromotive force (emf, E) measurements using improved electrochemical cells have afforded the derivation of mean ionic activity coefficients (γ's) of very dilute solutions of binary electrolytes, within the 10-10 molar range (Malatesta et al., J. Solution Chem.

Computing excess functions of ionic solutions: the smaller-ion shell model versus the primitive model. 2. Ion-size parameters.

A recent Monte Carlo (MC) simulation study of the primitive model (PM) of ionic solutions ( Abbas, Z. et al. J.

Computing excess functions of ionic solutions: the smaller-ion shell model versus the primitive model. 1. Activity coefficients.

The present study compares the Monte Carlo (MC) simulation of the primitive model (PM) ( Abbas, Z. et al. J.

Ion strength limit of computed excess functions based on the linearized Poisson-Boltzmann equation.

The linearized Poisson-Boltzmann (L-PB) equation is examined for its κ-range of validity (κ, Debye reciprocal length). This is done for the Debye-Hückel (DH) theory, i.e.

Theoretical analysis of aqueous solutions of mixed strong electrolytes by a smaller-ion shell electrostatic model.

In spite of the great importance of mixed electrolytes in science and technology, no compelling theoretical explanation has been offered yet for the thermodynamic behavior of such systems, such as their deviation from ideality and the variation of their excess functions with ionic composition and concentration. Using the newly introduced Smaller-ion Shell treatment - an extension of the Debye-Hückel theory to ions of dissimilar size (hence DH-SiS) - simple analytic mathematical expressions can be derived for the mean and single-ion activity coefficients of binary electrolyte components of ternary ionic systems. Such expressions are based on modifying the parallel DH-SiS equations for pure binary ionic systems, by adding to the three ion-size parameters - a (of counterions), b+ (of positive coions), and b- (of negative coions) - a fourth parameter.

Electrolytic nature of aqueous sulfuric acid. 2. Acidity.

In part 1 of this study, I reported that the Debye-Hückel limiting law and the smaller-ion shell (SiS) model of strong electrolyte solutions fit nicely with the experimental mean ionic activity coefficient (γ(±)) of aqueous sulfuric acid as a function of concentration and of temperature when the acid is assumed to be a strong 1-3 electrolyte. Here, I report that the SiS-derived activity coefficient of H(+), γ(H(+)), of the 1-3 acid is comparable to that of aqueous HCl. This agrees with titration curves showing, as well-known, that sulfuric acid in water is parallel in strength to aqueous HCl.

Electrolytic nature of aqueous sulfuric acid. 1. Activity.

According to the literature, when H(2)SO(4) dissolves in water, (1) it retains its molecular formula and tetrahedral structure of two O atoms and two OH groups bonded to a central S atom, and (2) it ionizes partially, as a 1-1 electrolyte, to H(+) (H(3)O(+)) and HSO(4)(-); the latter ion further dissociates at low concentrations (<0.1 M) to H(+) and SO(4)(2-). Using the Debye-Hückel (DH) limiting law at very low concentration, and the smaller-ion shell (SiS) model of strong electrolyte solutions-an extension of the DH model for ion size dissimilarity-up to moderate concentration, I examine the theory-experiment fit of the mean ionic activity coefficient (γ(±)) of the acid as a function of concentration (at 0 to ∼6 m) and of temperature (at 0-60 °C).

Single-ion activity: experiment versus theory.

The almost century-old dispute over the validity of the experimentally derived activity of a single ion, a(i), is still unsettled; current interest in this issue is nourished by recent progress in electrochemical cell measurements using ion-specific electrodes (ISEs) and advanced liquid junctions. Ionic solution theories usually give expressions for a(i) values of the positive and negative ions, that is, the respective a(+) and a(-), and combine these expressions to compute the mean ionic activity, a(±), that is indisputably a thermodynamically valid property readily derivable from experiment. Adjusting ion-size parameters optimizes theory's fit with experiment for a(±) through "optimizing" a(+) and a(-).

Effect of solvent permittivity on the thermodynamic behavior of HCl solutions: analysis using the smaller-ion shell model of strong electrolytes.

The recently introduced smaller-ion shell (SiS) treatment of strong binary electrolyte solutions [Fraenkel, D. Mol. Phys.

Monoprotic mineral acids analyzed by the smaller-ion shell model of strong electrolyte solutions.

The smaller-ion shell (SiS) model of strong binary electrolyte solutions extends the Debye-Hückel theory to the case of ions of unequal size; it is effective for many electrolytes of the various families in water at 25 °C up to moderate concentrations, with ion-size parameters (ISPs) of co-ions being equal to the ionic diameters, and with a varying degree of ISP additivity. A SiS analysis is now provided for aqueous solutions of the acids HCl, HBr, HI, and HClO(4) at 25 °C; theory fits very well with experiment when the mean effective ionic diameter of the proton (H(3)O(+)) is chosen as ~1.1 Å and the mean anion size is the corresponding crystallographic diameter, as with other electrolytes having the same anion.

A systematic review comparing the relative effectiveness of antimicrobial-coated catheters in intensive care units.

Background: Bloodstream infection related to a central venous catheter is a substantial clinical and economic problem. To develop policy for managing the risks of these infections, all available evidence for prevention strategies should be synthesized and understood.

Methods: We evaluate evidence (1985-2006) for short-term antimicrobial-coated central venous catheters in lowering rates of catheter-related bloodstream infection (CRBSI) in the adult intensive care unit.