A low molecular weight OLED material: 2-(4-((2-hydroxyethyl)(methyl)amino)benzylidene)malononitrile. Synthesis,crystal structure,thin film morphology,spectroscopic characterization and DFT calculations

2-(4-((2-Hydroxyethyl)(methyl)amino)benzylidene)malononitrile (HEMABM) was synthesized from 4-[hydroxymethyl(methyl)amino]benzaldehyde and propanedinitrile to obtain a low molecular weight fluorescent material with an efficient solid-state emission and electroluminescence properties comparable to the well-known poly(2-methoxy-5(2′-ethyl)hexoxyphenylenevinylene) (MEH-PPV). The HEMABM was used to prepare an organic light-emitting diode by a solution process. Despite the title compound being a small molecule, it showed optical properties and notable capacity to form a film with smooth morphology (10.81 nm) closer to that of polymer MEH-PPV (10.63 nm). The preparation of the device was by spin coating, the electrical properties such as threshold voltage were about 1.0 V for both HEMABM and MEH-PPV, and the luminance 1300 cd m⁻² for HEMABM and 2600 cd m⁻² for MEH-PPV. This low molecular weight compound was characterized by SCXRD, IR, NMR, and EI. Besides a quantitative analysis of the intermolecular interactions by PIXEL, density functional theory (DFT) calculations are reported.

A low molecular weight fluorescent malononitrile derivative showed an efficient solid-state emission and electroluminescence properties.     

Unusual adverse consequence of reverse ventricular remodelling following cardiac resynchronization therapy

Cardiac resynchronization therapy has been shown to produce reverse ventricular remodelling in patients with severe heart failure. We report an unusual case of T-wave oversensing, most likely as a consequence of reverse ventricular remodelling resulting in change of the implantable cardioverter-defibrillator lead redundancy.     

Torsades de pointes in a patient with Kearns-Sayre syndrome: a fortunate finding

We present a case of a 33-year-old woman with Kearns-Sayre syndrome (KSS) who had a pacemaker implanted for complete heart block postpartum and was found to have torsades de pointes. KSS is a rare encephalomyopathy associated with varying levels of central nervous system involvement, typically resulting in progressive external opthalmoplegia and retinal degeneration. Onset of cardiac conduction disease can be insidious and is a strong predictor of sudden cardiac death. The mainstay of treatment has been the judicious implantation of pacemakers. However, as highlighted in this case, patients who have an underlying cardiomyopathy may be more appropriately treated with an implantable cardioverter defibrillator.     

Determination of Non-Recrystallization Temperature for Niobium Microalloyed Steel

In the present investigation, the non-recrystallization temperature (T_NR) of niobium-microalloyed steel is determined to plan rolling schedules for obtaining the desired properties of steel. The value of T_NR is based on both alloying elements and deformation parameters. In the literature, T_NR equations have been developed and utilized. However, each equation has certain limitations which constrain its applicability. This study was completed using laboratory-grade low-carbon Nb-microalloyed steels designed to meet the API X-70 specification. Nb- microalloyed steel is processed by the melting and casting process, and the composition is found by optical emission spectroscopy (OES). Multiple-hit deformation tests were carried out on a Gleeble^® 3500 system in the standard pocket-jaw configuration to determine T_NR. Cuboidal specimens (10 (L) × 20 (W) × 20 (T) mm³) were taken for compression test (multiple-hit deformation tests) in gleeble. Microstructure evolutions were carried out by using OM (optical microscopy) and SEM (scanning electron microscopy). The value of T_NR determined for 0.1 wt.% niobium bearing microalloyed steel is ~ 951 °C. Nb- microalloyed steel rolled at T_NR produce partially recrystallized grain with ferrite nucleation. Hence, to verify the TNR value, a rolling process is applied with the finishing rolling temperature near TNR (~951 °C). The microstructure is also revealed in the pancake shape, which confirms T_NR.     

Perforation of Jejunal Diverticula in Steroids and Nonsteroidal Anti-Inflammatory Drug Abusers: A Case Series

INTRODUCTION: Jejunal diverticula are rare lesions, and when complications arise, they pose diagnostic difficulties. Perforation is a common complication resulting in an acute abdomen, although preoperative diagnosis is usually not possible. The "gold standard" for management for patients with complications is surgery. We present a series of patients with perforated jejunal diverticula who were on prolonged treatment with nonsteroidal anti-inflammatory drugs (NSAIDs) and steroids for Chikungunya fever. METHODS: There were a total of six patients, all of them presenting with perforative peritonitis, with or without shock. Plain abdominal radiogram and ultrasonogram confirmed this, although the exact site of the perforation was not diagnosed preoperatively. All patients underwent exploratory laparotomy and perforated jejunal diverticulum was found. Resection and anastomosis was performed in all cases. RESULTS: The mean operating time was 113.5 minutes, and the blood loss was not significant. Postoperative course was uneventful except wound infection in two patients. There was no mortality. CONCLUSIONS: Prolonged NSAID and steroid use are known to cause ulceration/perforation of the upper digestive tract and colonic diverticula. This seems to be the most likely cause for the perforation of jejunal diverticula in our series of patients. This view is supported by the absence of inflammation and infiltration of neutrophils on histopathological examination of the diverticula.