New generation nano-filler polymer composites have many applications including biomedical, electronic and maritime related applications because of their mechanical, electronic and optical properties. The properties of composites were investigated as a function of nano-filler content. Among these, tungsten disulfide (WS2) has the potential to be used as a component in electronic devices owing to its high electron mobility and easily tunable optical band gap energy. Tungsten disulfide (WS2)- Polyacrylamide (PAAm) composite was prepared using free radical co-polymerization and wet laboratory methods with WS2 content. Composites were characterized for mechanical and optical properties using an Elasticity Instrument and UV-vis Spectrophotometer, respectively. Elastic modulus was modeled by a statistical thermodynamics model. Tauc’s and Urbach’s Tail model for direct transition were used to model for the optical band gap. In this study, the swelling and WS2 effect on the optical band gap and elasticity of WS2 - PAAm composites were investigated. It was observed that the elasticity presented a reversed behavior of optical band gap energies with respect to WS2 content. For the applications of nano-filler doped polymer composites in flexible electronic devices, WS2 content strongly influences the mechanical and optical properties.

Objective: We aimed to investigate the frequency and possible risk factors of phototherapy-related direct hyperbilirubinemia. Material and Methods:We scanned the medical records of 1301 patients who were admitted to the neonatology unit for indirect hyperbilirubinemia between 2005 and 2013. Infants with a clinical condition other than hyperbilirubinemia were excluded. Results:Following phototherapy both the direct bilirubin level and direct bilirubin/total bilirubin ratio increased (p<0.001 and p<0.001, respectively). The frequency of phototherapy-related direct hyperbilirubinemia was found to be 0.9% if the direct bilirubin/total bilirubin cut-off level was set to 20%. The elevated direct bilirubin level and direct bilirubin/total bilirubin ratio returned to normal within three days, although they were still significantly higher than the pre-phototherapy levels (p < 0.001; p < 0.001, respectively). The increase in direct bilirubin level and direct bilirubin/total bilirubin ratio were found to be brisker in patients with ABO incompatibility (p < 0.001 and p < 0.001, respectively). Conclusion:The direct bilirubin level and direct bilirubin/total bilirubin ratio may temporarily rise following phototherapy. This deviation is short term, and ABO incompatibility is the only identified risk factor.To prevent unnecessary investigations this phenomenon should kept in mind by the physicians caring for infants. Bulgular: Fototerapiyi takiben hem direkt bilirubin seviyesi hem de direkt bilirubin/total bilirubin oranı artmaktadır (sı-rasıyla p < 0.001 ve p < 0.001). Patolojik direkt bilirubin/total bilirubin sınırı %20 alındığında, fototerapi ile ilişkili direkt hiperbilirubinemi sıklığı %0.9 olarak bulundu. Artmış direkt bilirubin seviyeleri ve direkt bilirubin/total bilirubin oranı 3 gün içerisinde normale dönmekteydi, fakat bu değerler halen fototerapi öncesindeki değerlere göre anlamlı olarak yüksekti (sırasıyla p < 0.001 ve p < 0.001). ABO uygunsuzluğu olan hastalarda direkt bilirubindeki ve direkt bilirubin/total bilirubin değerindeki artışın daha hızlı olduğu saptandı (sırasıyla p < 0.001 ve p < 0.001).Sonuç: Fototerapi sonrasında direkt bilirubin düzeyi ve direkt bilirubin / total bilirubin oranı geçici olarak artabilmektedir. Bu durum kısa sürelidir ve saptanabilen tek risk faktörü ABO uygunsuzluğudur. Gereksiz ileri araştırmaların önüne geçil-mesi açısından yenidoğanların tedavisinde görev alan doktorların bu durumu akılda tutmaları yararlı olacaktır.