MOLECULAR MECHANISM OF PHYSICAL AND MECHANICAL IMPROVEMENT IN GRAPHENE/GRAPHENE OXIDE-EPOXY COMPOSITE MATERIALS.

The performance provided by graphene (Gr) and graphene oxide (GO) additives can be improved by achieving strong adhesion and uniform dispersion in the epoxy resin matrix. In this study, molecular modeling and simulation of DGEBA/DETA based epoxy nanocomposites containing Gr and GO additives were performed. Density functional theory and molecular dynamics simulations were used to investigate interfacial interaction energies and Young's Modulus. Improvement in the interaction energies was studied by controlling the epoxy:hardener ratio, type and the number of oxygen-containing functional groups on the GO, the mass percentage of Gr/GO filler in the epoxy matrix, size and dispersion of GO in the cell. It was demonstrated that functional groups with up to 10% oxygen content in GO significantly increase interfacial interaction energy for large size Gr/GO. Increasing DETA type amine ratio in the preparation of epoxy polymers increases the interaction energy for high oxygen content while decreasing the interaction energy for low oxygen content in GO for small size GO with edge functional groups. The performance of material dramatically decreased even at high DETA hardener and high GO mass percentages when the aggregation factor of Gr/GO was included in simulations that explain lower Gr/GO percentages in the experimental studies.

Usefulness of the Leipzig Score in the Diagnosis of Wilson's Disease - A Diagnostically Challenging Case Report.

Wilson's disease (WD) is a genetic disorder of copper metabolism that is inherited as an autosomal recessive (AR) due to mutations in the ATP7B gene, which is involved in intracellular copper transport. Approximately 40% to 50% of the patients present with neurological symptoms as their first symptom. The most common neurological symptoms are dysarthria, gait abnormalities, ataxia, dystonia, tremor, parkinsonism, and drooling. This case report aims to present a diagnostically challenging case of WD presenting with neurological symptoms. The 38-year-old male patient was admitted with complaints of imbalance, gait disturbance, weakness in the legs, speech impairment, tremors in the hands, syncope, and drooling. The MRI primarily revealed FLAIR, T1, and T hyperintensities in the bilateral globus pallidus of the basal ganglias. At first, the patient was evaluated according to the Leipzig scoring and received one point from the serum ceruloplasmin level and two points from the neurological symptoms and was evaluated as "possible WD" with a total of three points. 24-hour urine copper was collected during and after the D-Penicillamine challenge. After the test, there was an increase of more than 5 times the upper limit. The Leipzig score was recalculated, and a diagnosis of WD was made with a score of five. Even cases without important diagnostic findings such as Kayser-Fleischer ring or high 24-hour urine copper should be evaluated according to the Leipzig score. It is vital to distinguish WD in patients with young-onset movement disorder and neurological symptoms.