Photo and electroluminescence behavior of Tb(ACAC)3phen complex used as emissive layer on organic light emitting diodes

This work shows the luminescence properties of a rare-earth organic complex, the Tb(ACAC)3phen. The results show the 5D4 -> 7F3,4,5,6 transitions with no influence of any ligand emission. The photoluminescence excitation spectrum is tentatively interpreted by the ligands absorption. An OLED was made by thermal evaporation (total thickness of 1200 Å) using TPD and Alq3 as hole and electron transport layers, respectively. The light emission reproduces the photoluminescence spectrum of the terbium complex at room temperature, with CIE (x,y) color coordinates of (0.28, 0.55). No presence of any bands from the ligands was observed. The potential use of this compound in efficient devices is discussed

Characterization of IHF Binding to DNA Four-Way Junctions and Forks

The objective of the study is to characterise the mechanical properties of Ti-15Zr binary alloy dental implants and to describe their biomechanical behaviour as well as their osseointegration capacity compared with the conventional Ti-6Al-4V (TAV) alloy implants. The mechanical properties of Ti-15Zr binary alloy were characterised using Roxoli

Ionization degree of the electron-hole plasma in semiconductor quantum wells

The degree of ionization of a nondegenerate two-dimensional electron-hole plasma is calculated using the modified law of mass action, which takes into account all bound and unbound states in a screened Coulomb potential. Application of the variable phase method to this potential allows us to treat scattering and bound states on the same footing. Inclusion of the scattering states leads to a strong deviation from the standard law of mass action. A qualitative difference between mid- and wide-gap semiconductors is demonstrated. For wide-gap semiconductors at room temperature, when the bare exciton binding energy is of the order of T, the equilibrium consists of an almost equal mixture of correlated electron-hole pairs and uncorrelated free carriers.Comment: 22 pages, 6 figure

Nutritional Evaluation Of Children With Chronic Cholestatic Disease

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)To evaluate the nutritional status of children with persistent cholestasis and to compare the anthropometric indices between children with and without liver cirrhosis and children with and without jaundice. Methods Children with persistent cholestasis, i.e. increased direct bilirrubin or changes in the canalicular enzyme gamma-glutamyl transferase (GGT), were included. The anthropometric measures were weight (W), height or length (H), arm circumference (AC), triceps skinfold thickness (TST), arm muscle circumference (AMC), and body mass index (BMI). Results Ninety-one children with cholestasis, with current median age of 12 months, were evaluated. W/age (A) and H/A indices below -2 Z-scores were observed in 33% and 30.8% of patients, respectively. Concerning the W/H index and BMI, only 12% and 16% of patients, respectively, were below -2 Z-scores. Regarding AC, 43.8% of 89 evaluated patients had some depletion. Observing the TST, 64% of patients had depletion, and 71.1% of the 45 evaluated patients had some degree of depletion regarding the ACM index. Conclusion Evaluation using weight in patients with chronic liver diseases may overestimate the nutritional status due to visceromegaly, subclinical edema, or ascites. Indices that correlate weight and height, such as W/H and BMI, may also not show depletion because of the chronic condition in which there are depletion of both weight and height. TST, AC, and ACM are parameters that better estimate nutritional status and should be part of the management of patients with liver diseases and cholestasis. © 2015 Sociedade Brasileira de Pediatria.922197205CNPq, Conselho Nacional de Desenvolvimento Científico e TecnológicoConselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq

Drug-loaded PCL electrospun nanofibers as anti-pancreatic cancer drug delivery systems

Cancer is one of the main causes of death worldwide, being pancreatic cancer the second deadliest cancer in Western countries. Surgery, chemotherapy and radiotherapy form the basis of pancreatic cancer's current treatment. However, these techniques have several disadvantages, such as surgery complications, chemotherapy systemic side effects and cancer recurrence. Drug delivery systems can reduce side effects, increasing the effectivity of the treatment by a controlled release at the targeted tumor cells. In this context, coaxial electrospun fibers can increase the control on the release profile of the drug. The aim of this study was to encapsulate and release different anticancer drugs (5-Fluorouracil and Methotrexate) from a polymeric fiber mat. Different flows and ratios were used to test their effect on fiber morphology, FTIR spectrum, drug encapsulation and release. Good integration of the anticancer drugs was observed and the use of a desiccator for 24 h showed to be a key step to remove solvent remanence. Moreover, the results of this study demonstrated that the polymeric solution could be used to encapsulate and release different drugs to treat cancers. This makes coaxial electrospinning a promising alternative to deliver complex chemotherapies that involve more than one drug, such as FOLFIRINOX, used in pancreatic cancer treatment

TARTESSUS: A customized electrospun drug delivery system loaded with Irinotecan for Local and sustained chemotherapy release in pancreatic cancer

Post-surgical chemotherapy in pancreatic cancer has notorious side effects due to the high dose required. Multiple devices have been designed to tackle this aspect and achieve a delayed drug release. This study aimed to explore the controlled and sustained local delivery of a reduced drug dose from an irinotecan-loaded electrospun nanofiber membrane (named TARTESSUS) that can be placed on the patients' tissue after tumor resection surgery. The drug delivery system formulation was made of polycaprolactone (PCL). The mechanical properties and the release kinetics of the drug were adjusted by the electrospinning parameters and by the polymer ratio between 10 w.t.% and 14 w.t.% of PCL in formic acid:acetic acid:chloroform (47.5:47.5:5). The irinotecan release analysis was performed and three different release periods were obtained, depending on the concentration of the polymer in the dissolution. The TARTESSUS device was tested in 2D and 3D cell cultures and it demonstrated a decrease in cell viability in 2D culture between 72 h and day 7 from the start of treatment. In 3D culture, a decrease in viability was seen between 72 h, day 7 (p < 0.001), day 10 (p < 0.001), 14 (p < 0.001), and day 17 (p = 0.003) as well as a decrease in proliferation between 72 h and day 10 (p = 0.030) and a reduction in spheroid size during days 10 (p = 0.001), 14 (p < 0.001), and 17 (p < 0.001). In conclusion, TARTESSUS showed a successful encapsulation of a chemotherapeutic drug and a sustained and delayed release with an adjustable releasing period to optimize the therapeutic effect in pancreatic cancer treatment