12 research outputs found
Occurrence of and Factors Associated With the Presence of Aflatoxin M1 in Breast Milk of Mothers in Fethiye, Turkey
No full textAflatoxins comprise a group of mycotoxins that are found in the environment. Exposure to aflatoxins has been reported to cause serious health problems in humans. Since aflatoxin M-1 (AFM(1)) is secreted in breast milk, the exposure of infants to this toxin is an important concern. The aim of this study was to determine the prevalence, levels of, and factors associated with the presence of AFM(1) in breast milk of mothers in Fethiye, Turkey. Breast milk samples were taken from 100 mothers who had given birth over the period of October-November 2017. The AFM(1) content of the samples was determined via enzyme-linked immunosorbent assay. The lowest limit for milk samples in the Ridascreen (R) AFM(1) commercial test kit is 5 ng/L. Because of this, AFM(1) levels below 5 ng/L in the breast milk samples were assessed as negative. Of the breast milk samples tested, 53 were positive. The average AFM(1) amount in the positive samples was 6.36 ng/L (ppt; range 5.10-8.31 ng/L). Mothers who were housewives, lived in damp, humid houses, or ate spices or dried fruits and vegetables had significantly greater prevalence of AFM(1) in their breast milk than those who were employed, did not report dampness or mold in the home, or did not eat spices or dried fruits and vegetables. AFM(1) in breast milk could be an important risk factor for infant health. Informing the public about food safety could reduce the amount of AFM(1) being transferred into breast milk via food channels.Mug. la Sitki Kocman University Research Projects Coordination Office [17/186]The author(s) disclosed receipt of the following financial support for the research and/or authorship of this article: Mug. la Sitki Kocman University Research Projects Coordination Office, project grant number 17/186
Calibration-free relaxation-based multi-color magnetic particle imaging
No full textMagnetic particle imaging (MPI) is a novel imaging modality with important potential applications, such as angiography, stem cell tracking, and cancer imaging. Recently, there have been efforts to increase the functionality of MPI via multi-color imaging methods that can distinguish the responses of different nanoparticles, or nanoparticles in different environmental conditions. The proposed techniques typically rely on extensive calibrations that capture the differences in the harmonic responses of the nanoparticles. In this paper, we propose a method to directly estimate the relaxation time constant of the nanoparticles from the MPI signal, which is then used to generate a multi-color relaxation map. The technique is based on the underlying mirror symmetry of the adiabatic MPI signal when the same region is scanned back and forth. We validate the proposed method via simulations, and via experiments on our in-house magnetic particle spectrometer setup at 10.8 kHz and our in-house MPI scanner at 9.7 kHz. Our results show that nanoparticles can be successfully distinguished with the proposed technique, without any calibration or prior knowledge about the nanoparticles.Manuscript received January 2, 2018; revised March 12, 2018; accepted March 16, 2018. Date of publication March 22, 2018; date of current version July 31, 2018. This work was supported in part by the Scientific and Technological Research Council of Turkey under Grant TUBITAK 114E167, in part by the European Commission through FP7 Marie Curie Career Integration under Grant PCIG13-GA-2013-618834, in part by the TUBA-GEBIP 2015 Program of the Turkish Academy of Sciences, and in part by the BAGEP 2016 Award of the Science Academy. (Corresponding author: Yavuz Muslu.) Y. Muslu, M. Utkur, and O. B. Demirel are with the Department of Electrical and Electronics Engineering, Bilkent University, 06800 Ankara, Turkey, and also with the National Magnetic Resonance Research Center (UMRAM), Bilkent University, 06800 Ankara, Turkey (e-mail: [email protected])
Shareholder Activism and CEO Pay
No full textWe study 134 vote-no campaigns and 1,198 shareholder proposals related to executive pay between 1997 and 2007. Union pension funds sponsor most of these initiatives, yet their targeting criteria do not appear to reflect labor-related motives. Shareholders favor proposals related to the pay-setting process (e.g., subject severance pay to shareholder approval) over proposals that micromanage pay level or structure. While activists target firms with high CEO pay (whether excessive or not), voting support is higher only at firms with excess CEO pay. Firms with excess CEO pay targeted by vote-no campaigns experience a significant reduction in CEO pay ($7.3 million). Our findings contribute to the debate on "say on pay" and other reforms empowering shareholders. The Author 2010. Published by Oxford University Press on behalf of The Society for Financial Studies. All rights reserved. For Permissions, please e-mail: [email protected]., Oxford University Press.
Effects of Oral Stimulation and Supplemental Nursing System on the Transition Time to Full Breast of Mother and Sucking Success in Preterm Infants: A Randomized Controlled Trial
No full textThis study aimed to investigate the effect of oral stimulation and a supplemental nursing system on the time to full maternal breastfeeding and sucking success in preterm infants. The sample consisted of 70 preterm babies. Oral motor stimulation and a supplemental nursing system were applied to the preterm infants in the experimental group, while no intervention was applied to those in the control group. Significant differences were found between the two groups concerning transition time to oral feeding, transition weight, transition time to full maternal breast, discharge age, duration, and weight, LATCH mean scores, continuing to suck in the first month after discharge, and weight averages. Oral stimulation and a supplemental nursing system shortened the transition period to oral feeding and full breastfeeding, increased breastfeeding rates and the sustainability of breastfeeding, and did not affect the period of discharge and vital signs during feeding in preterm babies. © The Author(s) 2021
Closing the gap in the purely elliptic generalized Davey-Stewartson system
No full textThe work of the first author is supported by Bogazici University Research Fund.In this note we improve the results presented previously on global existence and global nonexistence for the Solutions of the purely elliptic generalized Davey-Stewartson system. These results left a gap in the parameter range where neither a global existence result nor a global nonexistence result could be established. Here we are able to show that when the coupling parameter is negative there is no gap. Moreover, in the case where the coupling parameter is positive we reduce the size of the gap.Bogazici University Research FundPublisher's Versio
Microencapsulation of Caucasian blueberries (Vaccinium arctostaphylos L.) anthocyanins: Colour stability in varying storage conditions
No full textThe aim of this study was to investigate the extraction of anthocyanins from the fruits of Caucasian blueberry (Vaccinium arctostaphylos L.) and examine the colour stability of anthocyanins encapsulated through spray drying in model systems. The trials were conducted to determine the optimal conditions for anthocyanin extraction using an ultrasonic water bath at temperatures of 25, 50 and 75°C. The ideal anthocyanin extraction occurred at 25°C using 100% acetone in an ultrasonic bath for 15 min at 35 kHz. Anthocyanin concentrations were evaluated using the pH differential method. The extracted anthocyanins were encapsulated through spray drying with maltodextrin as the encapsulating material. The encapsulation efficiency was 80.4 ± 0.20%, and the anthocyanin retention rate was 83.0 ± 0.76%. The coloured capsules were added to model systems with pH values of 4.50, 5.00, 5.50 and 6.00. The colour values (L* 50.16 ± 0.05, a* 4.08 ± 0.04, b* −9.35 ± 0.01, H° 293.57 ± 0.15, C* 10.20 ± 0.03) were measured during varying storage conditions. The results showed, that colour loss began on the fifth day and this was accelerated with higher temperatures and pH values. It was found that encapsulation significantly preserved the stability of the blue colour and the loss of the blue colour followed first-order reaction kinetics. The study showed that the blue colour of microcapsules was best preserved at pH 5.00 at 25°C. In this case, the measured total colour change (∆E) was 5.86, the activation energy (Ea) was 37.64 kJ/mol, and the half-life (t1/2) was determined to be 19.08 days. © 2024 The Author(s). Coloration Technology published by John Wiley & Sons Ltd on behalf of Society of Dyers and Colourists
Thiol/disulfide homeostasis in patients with telogen effluvium: is oxidative stress important in the pathogenesis of telogen effluvium?
No full textObjective: The aim of this study was to assess the correlation between telogen effluvium (TE) with the new oxidative stress (OS) indicator of thiol/disulfide balance and to research the role of OS in the pathogenesis of TE. Methods: Our study included 101 patients with TE diagnosis and 39 healthy individuals. Serum thiol/disulfide was measured with a new automated spectrometric method developed by Erel and Neselioglu, and results were compared statistically. Results: Among the six thiol/disulfide parameters, there were statistically significant differences for native thiol, total thiol, disulfide, disulfide/native thiol, disulfide/total thiol, and native thiol/total thiol studied in the patient and control groups (P = 0.042, 0.044, < 0.001, respectively). Conclusions: Based on the results of this study, it can be said that OS is closely associated with TE pathogenesis. There is a need for new studies that will show the possible effects of OS on TE pathogenesis and research different OS markers in addition to thiol/disulfide parameters
