Matrix isolation technique for the study of some factors affecting the partitioning of trace elements

The factors that affect the preferred positions of cations in ionic solid solutions were investigated utilizing vibrational spectroscopy. Solid solutions of the sulfate and chromate ions codoped with La(+3) and Ca(+2) in a KBr host lattice were examined as a function of the polyvalent cation concentration. The cation-anion pairing process was found to be random for Ca(+2), whereas the formation of La(+3)-SO4(-2) ion pairs with a C2 sub v bonding geometry is highly preferential to any type of La(+3)-CrO4(-2) ion pair formation. The relative populations of ion pair site configurations are discussed in terms of an energy-entropy competition model which can be applied to the partition of trace elements during magmatic processes

Bialoruska autokefaliczna cerkiew prawoslawna na emigracji i udzial w jej dzialalnosci duchowienstwa ukrainskiego (Belarusian Autocephalous Orthodox Church in exile and participation in its activity of the Ukrainian clergy )

Po zakończeniu II wojny światowej na Zachodzie znalazła się pewna liczba Białorusinów. Za sprawą emigrantów białoruskich w 1948 roku na terytorium Niemiec doszło do reaktywacji Białoruskiej Autokefalicznej Cerkwi Prawosławnej. Jej parafie istniały w krajach Europy Zachodniej, obu Ameryk i Australii. Niebagatelny udział zarówno w reaktywacji, jak i dalszej działalności BAPC wzięło duchowieństwo ukraińskie. Przede wszystkim w działania na rzecz BAPC czynnie zaangażował się biskup Sergiusz (Ochotenko), którego działalność jest oceniana bardzo różnie w dostępnej literaturze przedmiotu (After World War II, in the West was a number of Belarusians. Thanks to Belarusian emigrants in 1948, in Germany came to a reactivation of the Belarusian Autocephalous Orthodox Church. Its parishes were in Western Europe, America and Australia. A substantial share in both reactivation as well as further activities of the Belarusian Autocephalous Orthodox Church took Ukrainian clergy. First of all, Bishop Sergij (Ochotenko) was actively involved to actions for the Belarusian Autocephalous Orthodox Church with whose activity is assessed very differently in the available literature

Controversies in the use of nutritional supplements in ophthalmology

Nutritional supplements are widely taken by the general population and several of these products are marketed specifically to improve eye health. The aim of this review is to summarise the evidence for the benefit of supplementation with antioxidant vitamins and other micronutrients for three of the most common eye diseases of the elderly: age-related macular degeneration (AMD), cataract and dry eye syndrome (DES). Although the potential importance of diet and nutrition in these conditions is strongly supported by data from observational studies, evidence from randomised controlled trials (RCTs) on the benefit of nutritional supplementation is generally lacking. However, there is high quality evidence to support the use of an Age-Related Eye-Disease Study (AREDS) supplement containing antioxidants ( -carotene, vitamin C and vitamin E) and zinc to slow progression in those at moderate to high risk of developing advanced AMD. Recent data from the AREDS2 trial provided data to suggest that -carotene could be replaced with lutein and zeaxanthin on the based on improved safety without compromising efficacy. Although there is currently insufficient evidence to recommend the routine use of any of the commercially available supplements in cataract and DES, given the public health importance of these conditions further research into the benefit of dietary modification or nutritional supplementation should be a priority

Direct vs. indirect optical recombination in Ge films grown on Si substrates

The optical emission spectra from Ge films on Si are markedly different from their bulk Ge counterparts. Whereas bulk Ge emission is dominated by the material's indirect gap, the photoluminescence signal from Ge films is mainly associated with its direct band gap. Using a new class of Ge-on-Si films grown by a recently introduced CVD approach, we study the direct and indirect photoluminescence from intrinsic and doped samples and we conclude that the origin of the discrepancy is the lack of self-absorption in thin Ge films combined with a deviation from quasi-equilibrium conditions in the conduction band. The latter is confirmed by a simple model suggesting that the deviation from quasi-equilibrium is caused by the much shorter recombination lifetime in the films relative to bulk Ge

Bilateral ectopic tubal pregnancy, following in vitro fertilisation (IVF).

This is a case report of a 33 year-old-woman who underwent in vitro fertilization, because of primary infertility caused by fallopian tube factor. The patient underwent three trials of frozen embryo transfers (ET-CRYO). On the 26th day after the third probe of ET-CRYO she suffered from pelvic pain and vaginal bleeding. Transvaginal ultrasonographic scan revealed bilateral tubal ectopic pregnancy without fluid in the Douglas pouch and no gestational sac in the uterus. Laparoscopic bilateral salpingectomy was performed on the next day after admission. The postoperative course was uneventful

Epidemiology, Etiology, and Prevention of Late IOL-Capsular Bag Complex Dislocation: Review of the Literature

Posterior chamber intraocular lens (PC-IOL) subluxation is uncommon but represents one of the most serious complications following phacoemulsification. Late spontaneous IOL-capsular bag complex dislocation is defined as occurring three months or later following cataract surgery. Unlike early IOL dislocation, late spontaneous IOL dislocation is due to a progressive zonular dehiscence and contraction of the capsular bag many years what seemed to be uneventful surgery. In recent years, late in-the-bag IOL subluxation or dislocation has been reported with increasing frequency, having a cumulative risk of IOL dislocation following cataract extraction of 0.1% after 10 years and 1.7% after 25 years. A predisposition to zonular insufficiency and capsular contraction is identified in 90% of reviewed cases. Multiple conditions likely play a role in contributing to this zonular weakness and capsular contraction. Pseudoexfoliation is the most common risk factor, accounting for more than 50% of cases. Other associated conditions predisposing to zonular dehiscence are aging, high myopia, uveitis, trauma, previous vitreoretinal surgery, retinitis pigmentosa, diabetes mellitus, atopic dermatitis, previous acute angle-closure glaucoma attack, and connective tissue disorders. The recognition of these predisposing factors suggests a modified approach in cases at risk. We review certain measures to prevent IOL-bag complex luxation that have been proposed

Yukawa potentials in systems with partial periodic boundary conditions II : Lekner sums for quasi-two dimensional systems

Yukawa potentials may be long ranged when the Debye screening length is large. In computer simulations, such long ranged potentials have to be taken into account with convenient algorithms to avoid systematic bias in the sampling of the phase space. Recently, we have provided Ewald sums for quasi-two dimensional systems with Yukawa interaction potentials [M. Mazars, {\it J. Chem. Phys.}, {\bf 126}, 056101 (2007) and M. Mazars, {\it Mol. Phys.}, Paper I]. Sometimes, Lekner sums are used as an alternative to Ewald sums for Coulomb systems. In the present work, we derive the Lekner sums for quasi-two dimensional systems with Yukawa interaction potentials and we give some numerical tests for pratical implementations. The main result of this paper is to outline that Lekner sums cannot be considered as an alternative to Ewald sums for Yukawa potentials. As a conclusion to this work : Lekner sums should not be used for quasi-two dimensional systems with Yukawa interaction potentials.Comment: 25 pages, 5 figures and 1 tabl

Calculation of iris-claw IOL power for correction of late in-the-bag IOL complex dislocation

Background: To assess the constants and formula for aphakia correction with iris-claw IOLs to achieve the best refractive status in cases of late in-the-bag IOL complex dislocation. Methods: A literature search was performed. The following data were obtained: Iris-claw IOL model, Iridal or retroiridal enclavation, A-constant, ultrasound or optical biometry, formula employed and refractive outcomes. Acceptable emmetropia was considered if the resulting spherical equivalent (SE) was within ±1.00 D. Results: The majority of the studies used SRK/T formula (66.6%). The 88.9% of the reports obtained a SE within ±1.00 D. Using A-115 for ultrasound biometry and A-115.7 for optical biometry and SRK/T formula, the emmetropia (±1.00 D) of SE, was able to get near 100% of reported cases over the pupil implantation. However, the emmetropia decreased to 80% when the enclavation is retropupilar using the same formula. The A-constant can vary from 116.7 to 117.5 for retropupilar enclavation. Conclusions: Using A-115 for ultrasound biometry and A-115.7 for optical biometry and SRK/T formula, ±1.00 D of SE, is able to get near 100% of cases. Nevertheless, ±1.00 D of SE decreased to 80% of the cases when the enclavation is retropupilar

Pseudophakic cystoid macular edema: update 2016

Pseudophakic cystoid macular edema (PCME) is the most common complication of cataract surgery, leading in some cases to a decrease in vision. Although the pathogenesis of PCME is not completely understood, the contribution of postsurgical inflammation is generally accepted. Consequently, anti-inflammatory medicines, including steroids and nonsteroidal anti-inflammatory drugs, have been postulated as having a role in both the prophylaxis and treatment of PCME. However, the lack of a uniformly accepted PCME definition, conflicting data on some risk factors, and the scarcity of studies comparing the role of nonsteroidal anti-inflammatory drugs to steroids in PCME prevention make the problem of PCME one of the puzzles of ophthalmology. This paper presents an updated review on the pathogenesis, risk factors, and use of anti-inflammatory drugs in PCME that reflect current research and practice