3D printed microfluidic reactor for high throuhput chitosan nanoparticle synthesis

The major bottleneck for the commercialization of nanoparticle related technologies is the mass production of the nanoparticles. One approach to overcome this bottleneck is use of microfluidic devices. In this paper, a 3D printed, high throughput micro-reactor that is capable of synthesizing both chitosan and chitosan coated iron oxide nanoparticles is presented

Paramagnetic signature of microcrystalline silicon carbide

Abstract. The most important challenge on the way to optimized solar cells is to make the thickness of the individual layers smaller than the diffusion length of the charge carriers, in order to keep the collection efficiency close to unity. Here, we propose ß-SiC microcrystals grown by a sol-gel based process as a promising acceptor material. The samples are characterized by optical spectroscopy and electron paramagnetic resonance (EPR). With the help of band structures for selected surface states calculated in the framework of density functional theory (DFT) a possible scenario for the observed acceptor process is discussed

A mathematical model for the behavior of laminated uniformly curved glass beams

Laminated curved glasses as widely used elements in buildings urge to develop a mathematical model for their analysis and safer design. Large deflection theory is necessary in order to predict the true behavior of a laminated curved glass beam consisting of several glass layers bonded by soft interlayer PVB (PolyVinyl Butyral). In the present study, a mathematical model is developed for the analysis of a laminated circular arch or a laminated uniformly curved glass beam which is the special case of the laminated curved glass beams. Thus, three nonlinear, coupled partial differential equations governing the true behavior are derived in polar coordinates by applying variational and energy principles. Results of this model are compared with the results from the experiments and finite element model, and all of them are presented in figures to explain the true behavior. © 2013 Elsevier Ltd

Türk tip 2 diabetik hastalar arasında HFE gen mutasyonu

Purpose: Hereditary haemochromatosis (HH) is a genetic disease with autosomal recessive trait. Recent studies demonstrated the importance of C282Y gene mutation in the aetiology of HH. Free iron accumulating in pancreas deteriorates insulin secretion and synthesis which can lead to insulin resistance and the development of type 2 diabetes mellitus (T2DM) in patients with HH. There has been no study determining the prevalence of haemochromatosis gene (HFE) mutations and HH in diabetic patients in Turkey. We planned this study in order to investigate the C282Y and H63D mutation that cause HH in T2DM. Material and Method: In this study, we included185 patients with T2DM. Patients older than thirty-five years, not taking vitamin supplementation, iron preparates and/or oral contraceptives and those without any signs of active bleeding were included while patients with any infectious, systemic or immune disease were excluded from the study. Serum transferrin saturation (TS), ferritin, iron, and total iron binding capacity levels were measured after 12 hours of fasting. Results: Ten (5.4%) cases with TS of more than 45% were detected at the first evaluation. The test was repeated in those cases and 6 patients with TS of more than 45% were left according to the second measurement. H63D and C282Y gene polymorphisms were not present in these patients. Discussion: We did not find any correlation between the existence of T2DM and HFE polymorphisms. We assume that screening for HH in T2DM in our population is not needed

Comparing various agents in rats for preventing gastric damage caused by non-steroid anti-inflammatory drugs [Siçanlarda non-steroid anti-inflamatuar i·laçla oluşan gastrik hasarlanmanin önlenmesinde farkli ajanlarin karşilaştirilmasi]

Objective: Non-steroid anti-inflammatory drugs (NSAIDs) may cause damage in the gastrointestinal system mucosa due to topical harm produced by metabolites as well as a decrease in the hydrophobicity of the stomach mucosa and suppression of prostaglandin synthesis. Protecting the mucosa from these effects means using prophylactic agents. In our study, we aimed to compare the effects of L-glutamine, L-arginine, L-carnitine and ranitidine in preventing these effects among rats whose stomachs were damaged after intake of naproxen and hydrochloric acid (HCl). Material and Methods: The rats included in this study were divided into five groups one of which was the control group and prophylactic agents were administered through the intragastric route to all groups for 10 days (Ranitidine: 50 mg/kg, glutamine: 750 mg/kg, arginine: 300 mg/kg, carnitine: 50 mg/kg). In the second stage 40 mg/kg naproxen sodium followed by 0.5 M HCl (10 cc/kg) were administered to the rats in order to produce damage in the stomach mucosa. After sacrification, stomach materials were examined macroscopically, histologically and histomorphologically. Differences between groups were analyzed using the Mann-Whitney U, Fischer's exact and one-way Anova tests. Statistical significance was set at p? 0.05. Results: Macroscopic examination revealed ulcerous mucosa in 60% and congestion as well as edema in 40% of rats not taking prophylactic agents during the test period. No lesion was present in 22.2% and 20% of the rats taking ranitidine and L-glutamine respectively, a wide-scale ulcer case was not discovered. On the other hand, no statistically significant difference in terms of macroscopic findings were determined between prophylactic agents (p> 0.05). Histological examination did not reveal any lesion in 28% of the rats in the ranitidine group and 4% of the control group (p< 0.05). Furthermore, we could not find any statistical difference between the control and prophylaxis groups in terms of average histomorphological measurements. However, significant differences between ranitidine and arginine groups appeared during histomorphological examinations (p< 0.05). Conclusion: We concluded that histological lesions developed less frequently in rats when they were given prophylactic agents to prevent damage in their stomach mucosa; the least damage in terms of morphological evaluation occurred in the ranitidine group. Further studies on this field, including biochemical mediators are required to accomplish higher rates of treatment in patients who widely depend on the intake of NSAIDs. Copyright © 2005 by Türkiye Klinikleri