Three uncommon morpholine-based fluorescent probes (A, B and C) for pH were prepared by introducing morpholine residues to BODIPY dyes at 4,4’- and 2,6-positions, respectively. In contrast to morpholine-based fluorescent probes for pH reported in literature, these fluorescent probes display high fluorescence in a basic condition while they exhibit very weak fluorescence in an acidic condition. The theoretical calculation confirmed that morpholine is unable to function as either an electron donor or an electron acceptor to quench the BODIPY fluorescence in the neutral and basic condition via photo-induced electron transfer (PET) mechanism because the LUMO energy of morpholine is higher than those of the BODIPY dyes while its HOMO energy is lower than those of the BODIPY dyes. However, the protonation of tertiary amines of the morpholine residues in an acidic environment leads to fluorescence quenching of the BODIPY dyes via d-PET mechanism. The fluorescence quenching is because the protonation effectively decreases the LUMO energy which locates between the HOMO and LUMO energies of the BODIPY dyes. Fluorescent probe C with deep-red emission has been successfully used to detect pH changes in mammalian cells.

First principles calculations based on hybrid density functional theory have been used to study the electronic and geometric properties of armchair silicon nanotubes from (4 4) to (12 12). Full geometry and spin optimizations have been performed without any symmetry constraints with an all electron 3-21G * basis set and the B3LYP functional. The largest silicon nanotube studied has a cohesive energy of 3.47 eV/atom. Atomic hydrogen and oxygen adsorptions on a Si(6 6) tube have been studied by optimizing the distances of the adatoms from both inside and outside the tube. The on-top external site is the most preferred site for hydrogen with an adsorption energy of 6.00 eV and an optimized distance of 1.50 A. For oxygen, the external normal bridge site is the most preferred site with an adsorption energy of 9.68 eV, the optimized distance being 1.66 A. In contrast to some published results, HOMO-LUMO gaps decrease for H adsorption but remain about the same for O adsorption. Radial buckling increases significantly due to H and O adsorptions.

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Background: Head injury is a common problem encountered in emergency department. Among various neurological diseases, cranio-cerebral trauma ranks high in order of frequency and gravity. In acute setting, computed tomography is modality of choice because of its high accuracy in detecting intracranial lesions. The study was done to analyze computed tomography findings in cerebral trauma in regards to sociodemographic characteristics and find out associations of Computed tomography findings with mechanism of injury and clinical manifestations.Methods: The study was carried in Department of Radiology, BPKIHS, over a period of one year from Aug. 2015 to Aug. 2016. 450 patients were included in our study and findings noted on structured pro forma. Analysis was done using SPSS version 20 applying simple descriptive statistical methods.Results: Among 450 patients, 220 patients (48.9%) had various cranio-cerebral injuries. Most were in age group of 20-29 years (49.5%) and most common mode was road traffic accident (44.6%).Most patients presented with altered sensorium (39.2%) and Glasgow Coma Scale score of ?13 (70.9%). Scalp lesion was the most common finding (24%) followed by bone fractures (19.8 %). Patients with road traffic accident (59.7%) and fall from height (46.7%) had more positive computed tomography findings than from physical assault (28.2%). Glasgow Coma Scale showed significant statistical association with computed tomography findings (p<0.001). Conclusions: Road traffic accident is the most common mode of head injury in young adults patients presenting in our hospital. Glasgow Coma Scale can be considered as an important clinical marker for predicting positive computed tomography findings. Also computed tomography is an important initial investigation to evaluate the various craniocerebral injury in trauma patients.Keywords: Computed tomography; Cranio-cerebral trauma; road traffic accident.