Adsorption properties of hydrazine on pristine and Si-doped Al₁₂N₁₂ nano-cage

The interaction of hydrazine (N₂H₄) molecule with pristine and Si-doped aluminum nitride (Al₁₂N₁₂) nano-cage was investigated using the density functional theory calculations. The adsorption energy of N₂H₄ on pristine Al₁₂N₁₂ in different configurations was about -1.67 and -1.64 eV with slight changes in its electronic structure. The results showed that the pristine nano-cage can be used as a chemical adsorbent for toxic hydrazine in nature. Compared with very low sensitivity between N₂H₄ and Al₁₂N₁₂ nano-cage, N₂H₄ molecule exhibits high sensitivity toward Si-doped Al₁₂N₁₂ nano-cage so that the energy gap of the Si-doped Al₁₂N₁₂ nano-cage is changed by about 31.86 and 37.61 for different configurations in the SiAlmodel and by about 26.10 in the SiNmodel after the adsorption process. On the other hand, in comparison with the SiAlmodel, the adsorption energy of N₂H₄ on the SiNmodel is less than that on the SiALmodel to hinder the recovery of the nano-cage. As a result, the SiNAl₁₂N₁₁ is anticipated to be a potential novel sensor for detecting the presence of N₂H₄ molecule. © 2016 Taylor & Francis Group, LLC

Electronic and optical properties of 5-AVA-functionalized BN nanoclusters: A DFT study

We carried out detailed density functional theory (DFT) and time-dependent density functional theory (TD-DFT) calculations upon 5-aminolevulinic acid-functionalized B12N12 and B16N16 nanoclusters with the B3LYP, B3PW91, and PBE methods using the 6-311+G∗∗ basis set. The calculated adsorption energies of 5-aminolevulinic acid with the BN nanoclusters were evaluated at T = 298.15 and 311.15 K in the gaseous and aqueous environments with the B3LYP, B3PW91, and PBE methods. Our results showed that the adsorption of the 5-AVA molecule (NH2 group) with B12N12 is more favorable than-with the B16N16 nanocluster in the gas and solvent phases. It is anticipated that a 5-aminolevulinic acid (5-AVA) drug incorporating BN clusters could find application in drug delivery systems and in biomedical devices. © The Royal Society of Chemistry and the Centre National de la Recherche Scientifique 2016

Phenol interaction with different nano-cages with and without an electric field: A DFT study

The adsorption properties of the phenol molecule (C6H5OH) upon the outer surfaces of C24, B12P12, B12N12, Al12N12, and Al12P12 were investigated using density functional theory calculations. Our calculations reveal that the phenol molecule can be chemisorbed on the sidewalls of Al12N12 and Al12P12 with adsorption energies of -1.03 and -0.76 eV, respectively. While the adsorption energy of C6H5OH on Al12N12 is typically more than that of Al12P12 cluster. We also considered the adsorption of the C6H5OH molecule under a strong electric field over Al12N12. The results indicate that Al12N12 has high sensitivity to the phenol molecule in the presence of an electric field. © Springer Science+Business Media 2014

BN Nanotube Serving as a Gas Chemical Sensor for N₂O by Parallel Electric Field

Density functional theory calculations were performed to understand the electronic properties of C₂₄, B₁₂N₁₂, B₁₂P₁₂, and (6, 0) BNNT interacted with N₂O molecule in the presence and absence of an external electric field using the B3LYP method and 6-31G** basis set. The adsorption of N₂O from O-side on the surface of (6, 0) BNNT has high sensitivity in comparison with B₁₂N₁₂ nano-cage. The adsorption energy of N₂O (O-side) on the sidewalls of B₁₂N₁₂ and BNNT in the presence of an electric field are −21.01 and −15.48 kJ mol⁻¹, respectively. Our results suggest that in the presence of an electric field, the B₁₂N₁₂ nano-cage is the more energetically notable upon the N₂O adsorption than (6, 0) BNNT, C₂₄, and B₁₂P₁₂. Whereas, our results indicate that the electronic property of BNNT is more sensitive to N₂O molecule at the presence of an electric field than B₁₂N₁₂ nano-cage. It is anticipated that BNNT could be a favorable gas sensor for the detection of N₂O molecule. © 2016, Springer Science+Business Media New York

A DFT study of 5-fluorouracil adsorption on the pure and doped BN nanotubes

Abstract The electronic and adsorption properties of the pristine, Al-, Ga-, and Ge-doped BN nanotubes interacted with 5-fluorouracil molecule (5-FU) were theoretically investigated in the gas phase using the B3LYP density functional theory (DFT) calculations. It was found that the adsorption behavior of 5FU molecule on the pristine (8, 0) and (5, 5) BNNTs are electrostatic in nature. In contrast, the 5FU molecule (O-side) implies strong adsorption on the metal-doped BNNTs. Our results indicate that the Ga-doped presents high sensitivity and strong adsorption with the 5-FU molecule than the Al- and Ge-doped BNNTs. Therefore, it can be introduced as a carrier for drug delivery applications. © 2015 Elsevier Ltd

Incidence and predisposing factors of cognitive disorders following off-pump coronary artery bypasses graft surgery

Patients and Methods: A total of 171 patients who had undergone off-pump CABG without any history of psychiatric disorders were enrolled. Samples were selected according to a purposive sampling method. The Mini-Mental State Examination (MMSE) questionnaire was given to each patients to assess the incidence of cognitive disorder during the first 24 hours of surgery in ICU. To compare creatinine, erythrocytes sedimentation rate, extubation time, and patients’ age between those with and those without postoperative cognitive disorder, independent-samplest test was employed. To compare two groups in terms of any history of diseases such as diabetes, hypertension, and hyperlipidemia, and qualitative C-reactive protein (CRP), Chi square test was used. Results: Results showed that 75% of patients had postoperative cognitive disorder. There was a significant association between the history of hypertension, CRP, and preoperative creatinine levels in both cognitive disorder and control groups. Background: Cognitive disorder, which is a common problem for the hospitalized patients, is a fluctuating cognitive destruction that leads to the loss of consciousness. It is usually accompanied by increased mortality, prolonged hospital stay, and decreased rehabilitation. Objectives: The purpose of this study was to determine the risk factors associated with cognitive disorder after coronary artery bypasses graft surgery (CABG). Conclusions: Given the significant prevalence of postoperative cognitive disorder and significant association between the history of hypertension, CRP, and preoperative creatinine and cognitive disorder, the detection of patient’s clinical symptoms may improve diagnosis, treatment, and even prevention of cognitive disorder. © 2014, Iranian Society of Regional Anesthesia and Pain Medicine (ISRAPM); Published by Kowsar

Carbon monoxide interactions with pure and doped B₁₁XN₁₂ (X = Mg, Ge, Ga) nano-clusters: a theoretical study

The goal of this investigation was to study a novel sensor for detecting the toxic gas compounds of CO using B₁₁XN₁₂ (X = Ge, Mg, and Ga) nano-clusters in terms of its energetic, geometric, and electronic structure using DFT calculations by the PBE-D method. The reaction of CO gas with these doping atoms results in a weak interaction and an elongation of X-N bond of B₁₁XN₁₂ nano-clusters. After the adsorption of CO gas over the doped positions of B₁₁XN₁₂ nano-cluster, the conductivity of the adsorbent and the atomic charges in some of the nearby B and N atoms around X atoms were dramatically enhanced. These calculations represent the capabilities of the B₁₁XN₁₂ nano-clusters in designing novel materials based on B₁₁XN₁₂ for potential applications in gas sensing. © The Royal Society of Chemistry

Swell-compression characteristics of a fiber-reinforced expansive soil

Abstract not availableAmin Soltani, An Deng, Abbas Taher

Contributions of anterior cingulate cortex and basolateral amygdala to decision confidence and learning under uncertainty.

The subjective sense of certainty, or confidence, in ambiguous sensory cues can alter the interpretation of reward feedback and facilitate learning. We trained rats to report the orientation of ambiguous visual stimuli according to a spatial stimulus-response rule that must be learned. Following choice, rats could wait a self-timed delay for reward or initiate a new trial. Waiting times increase with discrimination accuracy, demonstrating that this measure can be used as a proxy for confidence. Chemogenetic silencing of BLA shortens waiting times overall whereas ACC inhibition renders waiting times insensitive to confidence-modulating attributes of visual stimuli, suggesting contribution of ACC but not BLA to confidence computations. Subsequent reversal learning is enhanced by confidence. Both ACC and BLA inhibition block this enhancement but via differential adjustments in learning strategies and consistent use of learned rules. Altogether, we demonstrate dissociable roles for ACC and BLA in transmitting confidence and learning under uncertainty