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Diabetes mellitus is a commonly encountered diagnosis in hospitalised patients that is associated with prolonged admissions and mortality. One in six hospital beds in the UK are occupied by diabetes patients. Therefore, healthcare providers need to have a sound knowledge in managing in-patients with diabetes. Thus the aim of this clinical survey was to assess the diabetes-related knowledge of healthcare professionals in a district general hospital. A 24-item questionnaire, based on the 'Think Check Act (TCA)' diabetes modules implemented by the Healthcare Improvement Scotland was issued to the medical and nursing staff. Simple statistics were used for data collation and analysis. 30 questionnaires were completed by 10 doctors at varying stages of training, 17 nurses, 1 physician associate and 2 healthcare assistants. The mean percentage score of the participants were 57.4%. 22 (73.3%) correctly defined hypoglycaemia and 27 (90%) knew the location of hypo box and 7 (23.3%) were aware of TCA. Responses to other management related to diabetes emergencies were average. The responses between doctors and nurses were insignificant except for hypo box location (p = 0.0413). Knowledge about managing inpatient diabetes problems amongst healthcare professional at a district general hospital appears mediocre. Significant gaps have been identified which would be targeted for future educational events. [ABSTRACT FROM AUTHOR]

Linear and nonlinear optical (NLO) properties of triphenyl fused rhodamine analogues were estimated by spectroscopic based mathematical calculations and compared with computed values using density functional theory (DFT) calculations. Various Global hybrids (GHs) and range separated hybrids (RSHs) were utilized for reliable estimations of NLO properties. Spectroscopic based mathematical calculations of polarizability (α CT ), first order hyperpolarizability (β CT ) and second order hyperpolarizability (γ) were performed in varying polarity solvents. Spectroscopic based mathematical calculted α CT , β CT and γ values are found to have much closer agreement with the DFT computed values obtained by using RSHs. Comparative analysis of α CT , β CT and γ values suggested that these values increases with the increase of triphenylamine substitutions. Moreover, α CT , β CT and γ values increase with decreasing HOMO-LUMO band gap for all the dyes. N-[9-(isobenzofuran-1(3H)-one)-6-(dipnenylamino)-xanthene]-N-diphenyl amine having bis-triphenylamine substituent showed the largest NLO response among all analogues dyes. [ABSTRACT FROM AUTHOR]

[Display omitted] • Only four of the binary complexes formed between CH4 and CF4, on the one hand, and NH3, H2O, HF, PH3, H2S and HCl on the other, may be described as tetrel-bonded. • The interaction energies and the geometrical and spectroscopic properties are found to correlate with one another. • All complexes studies have extremely low binding energies. The binary complexes of ammonia, water, hydrogen fluoride, phosphine, hydrogen sulphide and hydrogen chloride, as electron donors, with methane and tetrafluoromethane, as electron acceptors, have been studied by means of ab initio molecular orbital theory. The properties of interest are the molecular structures, interaction energies and vibrational spectra of the complexes, and the interactions of the molecular orbitals which result in the formation of the complexes. The adducts were found to fall into a number of structural types, including tetrel-bonded, hydrogen-bonded, halogen-bonded, pnicogen-bonded and chalcogen-bonded, depending on the particular combination of electron donor and acceptor. The complexes, irrespective of the type of interaction, were found to be uniformly very weakly bound. The results have been rationalized in terms of the properties of the donors and, together with the conclusions of previous studies involving methyl fluoride, difluoromethane and fluoroform, with the extent of fluorine substitution in the parent molecule, methane. [ABSTRACT FROM AUTHOR]

A density functional theory study was performed on the [3+2] cycloaddition (32CA) reaction of 1 H -phosphorinium-3-olate and 1-methylphosphorinium-3-olate with methyl acrylate. The thermodynamic and kinetic parameters were analysed by considering the regio- and stereoisomeric pathways in gas phase and solvents. The geometries indicate that the transition states are slightly more advanced and asynchronous in ethanol. Electron localisation function topological analysis of the bonding changes along the most favourable reaction pathway associated with the 32CA reaction of 1 H -phosphorinium-3-olate with methyl acrylate indicates that the reaction takes place through a two-stage one-step mechanism. Non-covalent interactions analysis of TS6x-H reveals the existence of weak hydrogen bonding explaining the regioselectivity found in this low-polar zw-type 32CA reaction. On comparing these theoretical findings with the nitrogen analogues of the 32CA reactions, it is found that the regioselectivity is affected and the pathways are kinetically and thermodynamically enhanced. Therefore, a priori , the phosphorus cycloadducts could be synthesised. [ABSTRACT FROM AUTHOR]

Effective adsorption of pyridine (Py)- a major pollutant present in various industrial wastewaters onto silica derived from de-oiled mustard cake (DOMC ) was evaluated. Fourier transform infrared spectroscopy (FT-IR) and SEM were used to characterized the adsorbent. The paper describes data on the chemical composition of the DOMC, kinetics and equilibrium adsorption of Py as well as the effect of different operational parameters (temperature, pH, ionic strength and effect of urea) on the effective removal of Py from its aqueous solution. Adsorption data were modeled with the Freundlich, Langmuir, Redlich–Peterson (R–P) and Temkin isotherm. The adsorption data are found suitable for the studied models quite reasonably. However, the results describe the best representation of the Langmuir isotherm model (non-linear R 2 = 0.99). The adsorption process followed Lagergren first order kinetics. The experimental findings were complemented using density functional theory (DFT) to have more understanding at atomistic level. The possible adsorption interactions were discussed. The effects of process parameters such as pH, urea and ionic strength on the adsorption suggested that the adsorption of Py was attributed to hydrogen bonding; however, hydrophobic interactions and charge transfer interactions are also believed to be responsible for the observed adsorption in the present case. The experimental data were subsentiated by employing a silica model based on DFT. Experimental and theoretical modeling of the adsorption phenomenon suggest hydrogen bonding to be a dominant force for Py adsorption onto silica. [ABSTRACT FROM AUTHOR]

Highlights: [•] The 1,3-dipolar cycloaddition of pyrazinium-3-olates are studied theoretically. [•] The level of theory used is B3LYP/6-31G(d). [•] Parr functions were used to have a better understanding of the reaction mechanism. [•] The findings will be helpful for future synthesis of the reported compounds. [Copyright &y& Elsevier]

Highlights: [•] The structural parameters and energetics of some monomeric silanetellones are reported for the first time. [•] Silanetellones are viable molecules; their lowest vibrational frequency is >100cm−1. [•] Silanetellones are stable; their HOMO–LUMO gaps are large enough (2.10–4.52eV). [•] Electrophilicity (ω) of silanetellones are higher than their nucleophilicity (N). [•] These findings can help the experimental community in their hunt for novel silanetellones. [Copyright &y& Elsevier]

H(2-n)X(n)A=Te (X=H, F, Cl and Br; A=C, Si and Ge; n=0-2), the novel heavy congeners of formaldehyde, have been studied in the gas phase using MP2/def2-TVZP and BP86/def2-TVZP methods. Emphasis has been laid on the bond strengths and the standard heats of formation (ΔHf°) of the mentioned telluro-ketones to reveal their thermodynamic stabilities and further assist in their isolations. The bond strengths have been evaluated in terms of the σ-bond energy, π-bond energy and the bond dissociation enthalpy, D°, using isodesmic reaction schemes. The methodology employed has satisfactorily reproduced the bond strengths and the ΔHf° of formaldehyde and silanone. The findings from this work indicate that the D° of the F2A=Te (A=C, Si and Ge) molecules are comparable to that of H2C=O and thus their respective stabilities are expected to be equivalent to that of formaldehyde. Besides, the fluorinated telluro-ketones are predicted to possess a unique thermodynamic stability since they have the most exothermic ΔHf° in their respective series while the H2A=Te ketones have the most endothermic ΔHf°. In addition, the silanetellones are found to be thermodynamically more stable than their corresponding telluroformaldehyde and germanetellone analogs. Since reported data for H(2-n)X(n)A=Te (X=H, F, Cl and Br; A=C, Si and Ge; n=0-2) is non-existent in terms of the thermodynamic data, the findings of this work should supplement the literature with reliable information. [ABSTRACT FROM AUTHOR]

Abstract: The excited-state intramolecular proton transfer (ESIPT) fluorescence of the synthesised 2-(1,3-benzothiazol-2-yl)-5-(N,N- diethylamino)phenol (1) was studied using spectroscopic and theoretical methods. The changes in the electronic transition, energy levels, and orbital diagrams were investigated using the ab initio molecular orbital computation [B3LYP/6-31G(d)]. Compound (1) is fluorescent; it shows a single absorption and dual emission in solvents of different polarities. Experimental absorption and emission wavelengths are in good agreement with those predicted using the Time-Dependent Density Functional Theory [TD-B3LYP/6-31G(d)]. The photophysical properties of compound (1) are compared with benzoxazole and benzimidazole analogues. [Copyright &y& Elsevier]

Abstract: Ab initio calculations, at the second order level of Møller–Plesset perturbation theory and with Dunning’s augmented correlation-consistent polarised valence triple-zeta basis set, have been carried out on two series of molecular complexes. One set consists of the common bases ammonia, water, phosphine and hydrogen sulphide and the electron-acceptor halogens difluorine, dichlorine and dibromine, and the other comprises the interhalogens bromine fluoride, chlorine fluoride and bromine chloride as electron acceptors, with the same set of four bases. The interaction energies, molecular structures, vibrational spectra and charge distribution properties of the complexes have been computed, and the adducts have been characterised as halogen-bonded complexes. The trends in the values of these properties correlate with systematic changes in the base and the halogen species. The computed physical data are in quite good agreement with such experimental results as are available, while the anomalous features of some of the properties of the complexes with phosphine have been rationalised. [ABSTRACT FROM AUTHOR]

Abstract: We report the results of computational studies performed on the lowest doublet and quartet states of GaO4. Using density functional theory (DFT) and coupled cluster approach with 6-311+G(2df) basis set, the Cs end-on bonded superoxo complex proposed earlier for GaO4, from matrix experiments and computational studies, is thermodynamically unstable with respect to GaO4(2A′)→OGaO(2Πg) + O2() reaction. A kite-like C2v ground state geometry has been computed for GaO4. The energies of the low-lying states, harmonic vibrational frequencies and isotopic frequency ratios are reported for the GaO4 molecule. The adiabatic electron affinity of GaO4 is computed to be 3.74eV and 3.81eV at the B3LYP and CCSD(T)//B3LYP levels, respectively. [ABSTRACT FROM AUTHOR]

Abstract: The trans and gauche rotamers of 1,2-dihalogenodisilanes (XSiH2SiH2X; X=F, Cl, Br and I) have been studied in the gas phase using theoretical methods. The transition state arising from the trans-gauche isomerisation has also been modelled. The methods used are second order Møller-Plesset theory (MP2) and density functional theory (DFT). The basis set used is 6-311 ++G(d,p) for all atoms except that 6-311G(d,p) has been used for iodine atom only. B3LYP is the functional used for the DFT method and G2/MP2 and CCSD(T) computations have also carried out using the MP2 optimised structures. All the computations have been done using Gaussian 03W. All the structures have been fully optimised and the optimised geometries, dipole moments, moment of inertia and energies are reported. Energies of the optimised structures have been used to obtain the energy difference between the trans and gauche rotamers and the barrier of rotation. The optimised structures have been used for computations of vibrational frequencies and these frequencies are reported with appropriate assignments. It is found that the trans conformers are preferred and both the energy difference and rotational barrier increase as the size of the halogen increases. These observations have been interpreted in terms of steric or electrostatic repulsion and antiperiplanar hyperconjugation supported with NBO analysis. The findings from this work have also been compared with the analogous 1,2-dihalogenoethanes. Some of the predicted parameters compare satisfactorily with those reported in literature. The theoretical rate constant for the trans rotamer-transition state isomerisation is reported for the first time for this type of interconversion. The literature for these compounds is limited in terms of conformational investigations and therefore the data from this work should serve as a useful set for reference. [ABSTRACT FROM AUTHOR]

Leather is a unique material unmatched in properties by synthetics. Leather making is an environmentally challenged process. Tanning is the key process that renders stability to the skin matrix against microbial degradation, heat, sweat etc. Chromium(III) has been used widely in tanning for the excellent properties that it renders to the leather along with simplicity of operation. The reported toxicity of chromium compounds coupled with poor uptake of chromium during tanning process has challenged the continued use of this process. Problems associated with tanning have been classified as avoidable, controllable and unavoidable. Technological developments in avoidance and control of pollution in leather processing have come forth. There are both in-plant and end-of-pipe treatment solutions. This paper surveys the development of technologies that have rendered the tanning process eco-sustainable. A call for further understanding of the chemistry of tanning and need for cross-fertilization of ideas is made for enabling the greening of the tanning industry. [Copyright &y& Elsevier]

This study presents the first report of an ultrasound-assisted derivatization reaction between a carboxylic acid of etodolac (ETO) and a chiral derivatization reagent, (1 R )-(−)-menthyl chloroformate ( R -MCF). Fifty μL of deproteinated mouse serum containing ETO enantiomers was derivatized with 125 μL of 200 mM R -MCF and 17 μL of pyridine (a catalyst), with the reaction facilitated by ultrasonic radiation for 13 min, which were the optimal conditions as determined by response surface methodology. After quenching the reaction by adding an aqueous L-proline solution, the mixture was subjected to salting-out assisted liquid–liquid extraction (SA-LLE), which provided phase separation for sample concentration as well as cleanup. The ETO diastereomers were separated on a Phenomenex Gemini C 18 column (150 × 4.6 mm, 5 μm) under a simple gradient elution of a mobile phase containing a mixture of methanol: acetonitrile (10:1, V/V) and 10 mM acetic acid at a flow rate of 1.0 mL min −1 , followed by fluorescence detection with excitation and fluorescence emission wavelengths of 235 nm and 345 nm, respectively. The developed method was validated for specificity, sensitivity, linearity, accuracy, precision, stability, and matrix effect. A good linearity in the range of 0.5–50.0 μg mL −1 for each ETO enantiomer with r 2 > 0.998 and acceptable values for the intra-day and inter-day accuracy and precision as well as negligible matrix effects supported the suitability and reliability of the method. Finally, this method was used to analyze real samples taken from mice treated with (±)-ETO. [ABSTRACT FROM AUTHOR]

Abstract: Quantum mechanical methods have been employed to investigate the structural and spectroscopic properties of the novel trisilylsilylcyanide and trigermylgermylcyanide isolated molecules, in C3v symmetry, in the gas phase. The levels of theory used are DFT and MP2, the functional employed for the DFT method is B3LYP and the basis set used for all atoms is 6-311G(d,p). En route, the structures of these compounds have been analysed using the natural bond orbital approach. The latter confirms the presence of all single bonds and the only triple bond, namely, the Cn both of these molecules. Substituting silicon and germanium for carbon in the parent molecule, trimethylmethylcyanide, leave the bond length Cinvariant. Both the ab initio methods used perform satisfactorily when the predicted parameters from the two methods are compared. All the normal modes of vibrations were assigned to one of the 11 types of motion namely X–C stretch, X–X stretch, C, X–H stretch, X–X–C bend, X–X–X bend, X–C–X–H bend, XH3 rock, XH3 def and XH3 twist (X=Si or Ge). An interesting outcome of this work is that the HOMO–LUMO energy gap decreases from trimethylmethylcyanide to trigermylgermylcyanide. Since these compounds have not yet been synthesised, we have successfully compared the predicted parameters with related molecules for which results have been published in the literature. [Copyright &y& Elsevier]

Abstract: Theoretical methods have been employed to investigate the structural, spectroscopic and energetic properties of difluoro(germylthio)phosphine in the C s symmetry in the gas phase. The levels of theory used are MP2 and DFT/B3LYP and the basis set used for all atoms is 6-311G(d,p). The computed structural parameters, namely, bond lengths and bond angles and spectroscopic parameters, namely, infrared frequencies, Raman activities and NMR chemical shifts have been compared with experimental data reported in literature. The structure of this compound has been analysed using natural bond orbital approach. Both the ab initio methods perform satisfactorily when the predicted and experimental parameters are compared. We have extended this study, using the same methods and basis set, to the selenium analogue, namely, difluoro(germylseleno)phosphine for which literature is elusive. The MP2/6-311G(d,p) geometrical parameters for difluoro(germylseleno)phosphine are: r(P–Se)=2.270, r(Ge-Se)=2.386, r(P–F)=1.604, r(Ge–H)=1.530Å, ∠(Ge–Se–P)=91.4, ∠(F–P–F)=96.7, ∠(Se–P–F)=99.9 and ∠(Se–Ge–H)=109.5°. Apart from these, we have also studied the energetic parameters for their synthesis. The results indicate that formation of the sulphur-containing compound is favoured thermodynamically. [Copyright &y& Elsevier]

The rhenium(V) complexes [ReCl 3 ( t -BuNC)(L)(PPh 3 )] ( 1 – 3 ) were isolated by the reaction of trans -[Re III Cl 3 ( t -BuNC)(PPh 3 ) 2 ] ( t -BuNC = tert -butyl isocyanide) with the ligands H 2 L (H 2 L = aniline ( 1 ), o -phenylenediamine ( 2 ), anthranilic acid ( 3 )). In all these complexes the dianionic ligands L are coordinated monodentately as the imide. However, unexpectedly, with 2-aminophenol the complexes [Re V Cl 2 ( t -BuNC)(L)(PPh 3 ) 2 ](ReO 4 ) ( 4 ) and the novel [Re III Cl 2 ( t -BuNC)(ibq)(PPh 3 ) 2 ] ( 5 ) (ibq − = 2-iminobenzoquinonate, the two-electron oxidized form of HL − ) were identified as the products. These complexes were characterized by single crystal X-ray crystallography, 1 H NMR spectrometry, IR and electronic spectroscopy, and cyclic voltammetry. To complement the experimental data, density functional theory (DFT) and time-dependent DFT methods were used to have a deeper understanding into the molecular parameters and infrared and electronic spectra of these complexes. [ABSTRACT FROM AUTHOR]

The reaction of the rhenium(V) complex cis-[ReO2I(PPh3)2] with 2-aminothiophenol (H2atp), benzene-1,2-dithiol (H2tdt) and 2-hydroxybenzenethiol (H2otp) led to the formation of the rhenium(III) complexes [Re(Hatp)(ibsq)2]·OPPh3, [Re(sbsq)3]·OPPh3 and [Re(obsq)3]·OPPh3 (ibsq=2-iminothiobenzosemiquinonate, sbsq=1,2-dithiobenzosemiquinonate, obsq=2-hydroxothiobenzosemiquinonate) respectively. These paramagnetic complexes were characterized by single crystal X-ray crystallography, 1H NMR spectrometry, IR and electronic spectroscopy, and cyclic voltammetry. To complement the experimental data, density functional theory (DFT) and time-dependent DFT were successfully used to investigate the structural, molecular, infrared and electronic spectra of these three complexes. [ABSTRACT FROM AUTHOR]