Effect of Yb substitution in Bi-2212 ceramics prepared by laser floating zone technique

In the present work, the influence of Yb substitution for Bi on the structural, electrical and magnetic properties of textured Bi-2212 ceramics has been investigated. X-ray diffraction studies indicated that the major peaks correspond to the Bi-2212 phase. The SEM images clearly show that there is an increase in the number of secondary phases with raising Yb content while all samples maintain similar grain morphology. Magnetic analysis of all samples has been done by magnetic hysteresis measurements, indicating that an enhancement in the M-H loops is obtained by a low Yb doping. The critical current density of samples was calculated from the M-H curves by using Bean’s critical state model, indicating that sample with 0.05 Yb substitution possesses the highest Jc values.The authors wish to thank the Gobierno de Aragón and Fondo Social Europeo (Grupos de Investigacion Consolidados T12 and T87) and MINECO-FEDER (MAT2013-46505-C3-1-R) for financial support.Peer Reviewe

Improving thermoelectric properties of Ca 3 Co 4 O 9+d through both Na doping and K addition at optimal values

Ca 2.93 Na 0.07 Co 4 O y /x wt% K 2 CO 3 (x = 0.00, 0.01, and 0.03) polycrystalline ceramics were prepared by conventional solid-state method. XRD results have shown that all samples predominantly include Ca 3 Co 4 O 9 phase together with small amounts of secondary phases. SEM images show that all samples have randomly oriented plate-like grains in different sizes. The electrical resistivity measurement showed that electrical properties of Ca 3 Co 4 O 9 ceramics can be improved significantly by both, Na doping and K addition at their optimal values. The effect of dopants on thermoelectric properties of Ca 3 Co 4 O 9 was examined by both, Seebeck coefficient and power factor, being higher in K-added than in the pure samples, indicating that thermoelectric properties of samples are positively affected when alkaline elements enter into their structure

Effect of heparin in the intraocular irrigating solution on postoperative inflammation in the pediatric cataract surgery

Yelda B Özkurt, Arzu Taskiran, Nadire Erdogan, Baran Kandemir, Ömer K Dog?anDepartment of Ophthalmology, Kartal Training and Research Hospital, Istanbul, TurkeyPurpose: To evaluate the influence of irrigation of the anterior chamber with heparin sodium on postoperative inflammation after pediatric cataract surgery. Setting: Kartal Training and Research Hospital, First Eye Clinic, Istanbul, Turkey.Design: Randomized prospective double-blind study.Methods: Fourteen consecutive eyes from 14 patients aged 8.9 ± 5.9 years, (range 3–18 years) (group 1) and 19 eyes from 19 patients aged 9.1 ± 5.2 (range 1.5–18 years) (group 2) underwent pediatric cataract surgery. Five patients in group 1 were between three and five years old. One patient was 1.5 years old and six patients in group 2 were between three and five years old. During the procedure, group 1 received anterior chamber irrigation with heparin sodium (5 IU/cc) and 1 ml of heparin sodium (concentration 10 IU/ml) added to the irrigating balanced salt solution (BSS Plus; Alcon Laboratories, Inc., Fort Worth, TX, USA) while group 2 received BSS without heparin sodium only. Cases aged under three years received anterior vitrectomy in addition to posterior capsulorrhexis. One eye received anterior vitrectomy in group 1 and two eyes received anterior vitrectomy in group 2. Cases with preoperative complications were not included in the study. Early and late postoperative inflammatory complications, including fibrin formation, anterior and posterior synechia, cyclitic and pupillary membrane formation were recorded and compared.Results: Mild anterior chamber reaction was observed in three patients in Group 1, while nine cases in group 2 experienced marked anterior chamber reaction. In four of nine patients from group 2, anterior chamber reaction was severe and resulted in pupillary membrane and synechia despite treatment in the postoperative 7th day, while in all three cases in group 1, reaction disappeared by the 7th day.Conclusion: Anterior chamber irrigation with heparin during pediatric cataract surgery may minimize early inflammatory reaction and decrease the number of postoperative inflammatory related complications.Keywords: pediatric, cataract, surgery, inflammatio

Nuclear anomalies in the buccal cells of calcite factory workers

The micronucleus (MN) assay on exfoliated buccal cells is a useful and minimally invasive method for monitoring genetic damage in humans. To determine the genotoxic effects of calcite dust that forms during processing, MN assay was carried out in exfoliated buccal cells of 50 (25 smokers and 25 non-smokers) calcite factory workers and 50 (25 smokers and 25 non-smokers) age- and sex-matched control subjects. Frequencies of nuclear abnormalities (NA) other than micronuclei, such as binucleates, karyorrhexis, karyolysis and ‘broken eggs', were also evaluated. Micronuclei and the other aforementioned anomalies were analysed by two way analysis of covariance. The linear correlations between the types of micronucleus and nuclear abnormalities were determined by Spearman's Rho. There was a positive correlation between micronuclei and other types of nuclear abnormalities in accordance with the Spearman's Rho test. Results showed statistically significant difference between calcite fabric workers and control groups. MN and NA frequencies in calcite fabric workers were significantly higher than those in control groups (p < 0.05). The results of this study indicate that calcite fabric workers are under risk of significant cytogenetic damage

Prevalence and risk factors of allergies in turkey (PARFAIT): Results of a multicentre cross-sectional study in adults

The Prevalence and Risk Factors of Allergies in Turkey (PARFAIT) study was planned to evaluate the prevalence of and risk factors for asthma and allergic diseases in Turkey. The present analysis used data from 25,843 parents of primary school children, obtained from a cross-sectional questionnaire-based study. A total of 25,843 questionnaires from 14 centres were evaluated. In rural areas, the prevalences asthma, wheezing, allergic rhinitis and eczema in males were: 8.5% (95% confidence interval (CI) 7.9-9.1%), 13.5% (95% CI 12.8-14.2%), 17.5% (95% CI 16.7-18.2%) and 10.8% (95% CI 10.211.4%), respectively; and in females were: 11.2% (95% CI 10.9-11.8%), 14.7% (95% CI 14.315.1%), 21.2% (95% CI 20.4-22.0%) and 13.1% (95% CI 2.4-13.8%), respectively. In urban areas, the corresponding prevalences in males were: 6.2% (95% CI 5.8-6.6%), 10.8% (95% CI 10.311.3%), 11.7% (95% CI 11.4-12.0%) and 6.6% (95% CI 6.2-7.0%), respectively; and in females were: 7.5 % (95% CI 7.9-7.1%), 12.0% (95% CI 11.7-12.3%), 17.0% (95% CI 16.4-17.6%) and 7.3% (95% CI 6.9-7.7%), respectively. Having an atopic first-degree relative or any other atopic diseases had significant effects on the prevalence of allergic diseases. Housing conditions, such as living in a shanty-type house, visible moulds at home and use of wood or biomass as heating or cooking material were associated with one or more allergic diseases. Although genetic susceptibility is strongly associated, country-and population-based environmental factors may contribute to increased prevalence rates of allergic diseases. Copyright © ERS Journals Ltd 2009

Metabolic syndrome and cardiovascular disease after haematopoietic cell transplantation (HCT) in adults: an EBMT cross-sectional non-interventional study

Metabolic syndrome (MetS) is associated with cardiovascular disease in the general population and is also a potential cardiovascular risk factor in survivors of haematopoietic cell transplantation (HCT). We report an EBMT cross-sectional, multi-centre, non-interventional study of 453 adult HCT patients surviving a minimum of 2 years post-transplant attending routine follow-up HCT and/or late effects clinics in 9 centres. The overall prevalence of MetS was 37.5% rising to 53% in patients >50 years of age at follow-up. There were no differences in rates of MetS between autologous and allogeneic HCT survivors, nor any association with graft-versus-host disease (GvHD) or current immunosuppressant therapy. Notably, there was a significantly higher occurrence of cardiovascular events (CVE, defined as cerebrovascular accident, coronary heart disease or peripheral vascular disease) in those with MetS than in those without MetS (26.7% versus 9%, p < 0.001, OR 3.69, 95% CI 2.09–6.54, p < 0.001), and, as expected, MetS and CVE were age-related. Unexpectedly, CVE were associated with occurrence of second malignancy. Screening for and management of MetS should be integrated within routine HCT long-term follow-up care for both allogeneic and autologous HCT survivors. Further research is warranted, including randomised controlled trials of interventional strategies and mechanistic studies of cardiovascular risk in HCT survivors

Physical, mechanical and magnetic properties of the Yb-substituted Bi 2Sr2Ca1Cu2Oy textured superconductor

In this study, samples with nominal composition of Bi2Sr 2Ca1Cu2-x Yb x O y, where x=0.0, 0.05, 0.1 and 0.25, have been textured using the Laser Floating Zone technique. The effects of different Yb doping on the structure have been investigated by electrical resistivity, scanning electron microscopy, XRD, mechanical and dc-magnetization techniques. It has been found that with increasing Yb3+ doping for Cu, the physical and superconducting properties of structure gradually decrease. J C values, calculated using the Bean's model, significantly change, although T C is approximately the same for all samples. © 2012 Springer Science+Business Media, LLC.This work is supported by the Research Fund of Cukurova University, Adana, Turkey, under grant contracts No. FEF 2011D21. The Spanish MICINN-FEDER (Project MAT2008-00429) and the Gobierno de Aragón (Consolidated Research Group T12) are acknowledged for financial support.Peer Reviewe

Effect of Ce substitution on structural and superconducting properties of Bi-2212 system

In this study, Bi2Sr2Ca1-xCe xCu2Oy, where x = 0, 0.01, 0.05, 0.1 and 0.25, superconducting samples were prepared by solid state method and subsequently used as feed in a laser induced directional solidification (LFZ) process. The physical properties of the samples were investigated by powder X-ray diffraction, scanning electron microscopy, dc-electrical resistance, magnetization, and magnetic-hysteresis loops measurements. It has been found that no significant difference has been observed in the critical transition temperatures of samples except for the sample with the highest Ce additions, which shows the lowest TC compared with the other doped samples. Magnetic hysteresis measurements have shown that the hysteresis loop is greater than the doped samples. In addition, critical current density values obtained from the hysteresis loops measurements by using Bean's critical state model show a decrease with Ce-addition. All the results indicate that Cerium substitution for Ca produces the deterioration on the superconducting properties, compared with the undoped sample.This work is supported by Research Fund of Çkurova University, Adana, Turkey, under grant contracts no: FEF2011YL27. A. Sotelo and M. A. Madre wish to thank the Gobierno de Aragón (Research Group T12), for financial support. M.A. Madre also acknowledges the MINECO-FEDER (Project MAT2011-22719) for funding.Peer reviewe

Structural, electrical, and magnetic properties of the co-substituted bi-2212 system textured by laser floating zone technique

In this work, Bi2Sr2CaCu2-x Co x O y (x=0.0, 0.05, 0.10, and 0.25) textured superconductors were prepared by a LFZ melting technique. In all cases, the powder X-ray diffraction patterns of samples show that the Bi-2212 phase is the major one. All samples have good oriented structure, which is a typical picture for superconductors prepared by the LFZ method. Magnetization hysteresis loops, made for all samples at two different temperatures, showed that the loops become narrower with increasing temperature and doping levels. In addition, the effect of Co doping on the critical current density, J c, of Bi 2Sr2CaCu2-x Co x O y has been estimated from hysteresis loop measurement by using Bean's model. The increase of the Co amount in the Bi2Sr2CaCu2-x Co x O y structure significantly decreases the critical current density, showing worse connectivity of the grains. All the results indicate that Co substitution for Cu produces the deterioration on the superconducting properties, compared with the undoped samples. © 2013 Springer Science+Business Media New York.This work is supported by Research Fund of Çukurova University, Adana,Turkey, under grant contracts nº FEF2012YL7. A. Sotelo and M.A. Madre wish to thank the Gobierno de Aragón (Research Group T12), for financial support. M.A. Madre also acknowledges the MINECO-FEDER (Project MAT2011-22719) for funding.Peer Reviewe

Modification of physical and structural properties of Bi1.8Pb0.4Sr2Ca2.2Cu3Oy ceramics induced by annealing

The effect of annealing temperatures on the structural and superconducting properties of Bi-2223 ceramics prepared by the solid state reaction method has been investigated. Annealing temperatures were varied from 730 to 830 °C while time was kept constant at 50 h. Electrical resistivity studies showed that samples annealed at 830 °C for 50 h have the lowest resistivity values at room temperature while critical transition temperature increases slightly. XRD data have shown that all samples contain Bi-2223 as the major one. The highest diamagnetism behavior has been found in the sample treated at 830 °C. In addition, Jc values of the samples, calculated from the hysteresis loops using the Bean's model, decreased with increasing annealing temperatures until 780 °C and increase for the highest annealing temperature which is 830 °C for this work. © 2013 Elsevier B.V. All rights reserved.M.A. Madre, J.C. Diez and A. Sotelo wish to thank the Gobierno de Aragón (Consolidated Research Groups T87 and T12) for financial support. M.A. Madre acknowledges the MINECO-FEDER(Project MAT2011-22719) for funding.Peer Reviewe