Influence of dispersing agents on the solubility of perovskites in water

In this study, solubility behavior of lead magnesium niobate (PMN) powders in water was investigated in the presence of pure polyacrylic acid and polyacrylic acid/polyethylene oxide comb polymers. Experiments were performed by measuring the solubility of PMN in terms of the concentration of Pb+2 and Mg+2 ions in supernatant as a function of pH and dispersing agent dosage. The concentrations of the metal ions in supernatant were found to be affected by the dispersant concentration, stirring time and the suspension pH. Results revealed that both dispersing agents enhance the cation dissolution from PMN surface at pH 9 due to weak (reversible) adsorption and complexation of Pb+2 and Mg+2 by carboxylate groups. On the other hand, under acidic conditions cation dissolution from PMN is inhibited and this was attributed to the strong adsorption of dispersing agents onto the powder surface and formation of a dense polymer layer

THE EFFECT OF MEMBER GROUPING ON THE OPTIMUM DESIGN OF GRILLAGES VIA SEARCH TECHNIQUES

Member grouping of a steel grillage system has an important effect in the minimum weight design of these systems. In the present research, this effect is investigated using an optimum design algorithm which is based on two stochastic search techniques called particle swarm (PSO) and harmony search (HS) optimization methods. The optimum design problem of a grillage system is formulated by implementing LRFD-AISC (Load and Resistance Factor Design-American Institute of Steel Construction) limitations. It is decided that W-Sections are to be adapted for the longitudinal and transverse beams of the grillage system. 272 W-Section beams given in LRFD code are collected in a pool and the optimum design algorithm is expected to select the appropriate sections from this pool so that the weight of the grillage is the minimum correspondingly the design limitations implemented from the design code are satisfied. The solution for this discrete programming problem is determined by using the PSO and HS algorithms. Design example is presented to demonstrate the effect of beam spacing and performances of stochastic search techniques in the optimum design of grillage systems

Tick bite cases among hazelnut farm workers in Giresun

Ticks are arthropod vectors of many diseases. The prevalence of Lyme disease transmitted by Ixodes is not known in Turkey. The disease is caused by Borrelia species and can also be seen in domestic animals. The aim of this study is to identify the ticks, which are collected from the agricultural workers who admitted to hospitals during the hazelnut harvest season between August and September 2015, at species and genus level and investigate whether these ticks vector of Borrelia spp. Method: In this study, 152 ticks collected from 134 patients were investigated. Of all samples including larvae and nymphs, 95.24% were collected in September. All patients who admitted with complaints of tick bites were agricultural workers collecting nuts in the gardens at sea level. The ticks were identified at species and genus level with stereomicroskop, hemolymph fluid examined directly by dark-field microscope and cultured in the Borellia BarbourStoenner-Kelly (BSK-H) medium. Results: Of all the ticks, 126 (82.9%) were adults, 13 (8.55%) were nymphs and 13 (8.55%) were larvae. Stereoscopic examination of the ticks revealed that 125 (82.2%) of the adults were Ixodes ricinus and 1 (0.65%) was Rhipicephalus sanguineus. All of the 13 nymphs (8.55%) and 13 larvae (8.55%) were identified as Ixodes spp.. All forms of development cycle were detected in the samples and the forms were inconsistent with the expected development cycle. Borrelia spp., the agent of Lyme disease, was investigated in the 146 ticks defined as I. ricinus and Ixodes spp. Borrelia spp were detected by dark field microscope in 3 (2.05%) of the 146 Ixodes and Borrelia spp. were identified in 5 (3.4%) of the cultures. Conclusions: These results demonstrate that Lyme disease can be seen in our region and the most probable vector is Ixodes ricinus

Non-Penetrating Wounds of the Chest

The heart may be seriously injured by compression of the chest by a steering wheel in automobile accidents or in other injuries by non-penetrating blows to the chest. These injuries vary from a simple bruise of the heart to actual laceration of heart muscle and heart valves. The changes may be identified by electrocardiograph and changes in heart rhythm. Attorneys should make certain that any injury by a blow to the chest is studied by a cardiologist, using not one but a series of electrocardiographs, as even seemingly harmless blows to the chest may result in injuries equivalent to heart attacks

Volume CXIV, Number 4, November 7, 1996

Objective: Turner syndrome (TS) is a chromosomal disorder caused by complete or partial X chromosome monosomy that manifests various clinical features depending on the karyotype and on the genetic background of affected girls. This study aimed to systematically investigate the key clinical features of TS in relationship to karyotype in a large pediatric Turkish patient population.Methods: Our retrospective study included 842 karyotype-proven TS patients aged 0-18 years who were evaluated in 35 different centers in Turkey in the years 2013-2014.Results: The most common karyotype was 45,X (50.7%), followed by 45,X/46,XX (10.8%), 46,X,i(Xq) (10.1%) and 45,X/46,X,i(Xq) (9.5%). Mean age at diagnosis was 10.2±4.4 years. The most common presenting complaints were short stature and delayed puberty. Among patients diagnosed before age one year, the ratio of karyotype 45,X was significantly higher than that of other karyotype groups. Cardiac defects (bicuspid aortic valve, coarctation of the aorta and aortic stenosis) were the most common congenital anomalies, occurring in 25% of the TS cases. This was followed by urinary system anomalies (horseshoe kidney, double collector duct system and renal rotation) detected in 16.3%. Hashimoto's thyroiditis was found in 11.1% of patients, gastrointestinal abnormalities in 8.9%, ear nose and throat problems in 22.6%, dermatologic problems in 21.8% and osteoporosis in 15.3%. Learning difficulties and/or psychosocial problems were encountered in 39.1%. Insulin resistance and impaired fasting glucose were detected in 3.4% and 2.2%, respectively. Dyslipidemia prevalence was 11.4%.Conclusion: This comprehensive study systematically evaluated the largest group of karyotype-proven TS girls to date. The karyotype distribution, congenital anomaly and comorbidity profile closely parallel that from other countries and support the need for close medical surveillance of these complex patients throughout their lifespa