Stepwise basis set selection

Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/146410/1/jcc25363.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/146410/2/jcc25363_am.pd

South African surgical registrar perceptions of the research project component of training: Hope for the future?

Background. The Health Professions Council of South Africa requires that a research project be submitted and passed before registration as a specialist.Objective. To describe surgical registrars’ perceptions of the compulsory research project.Method. Ethics clearance was received before commencing the study. A questionnaire was developed to collect feedback from surgical registrars throughout South Africa (SA). Completed questionnaires underwent descriptive analysis using MS Excel. Fisher’s exact test and the χ2 test were used to compare perceptions of the research-experienced and research-naive groups.Results. All medical schools in SA were sampled, and 51.5% (124/241) of surgical registrars completed the questionnaire. Challenges facing registrars included insufficient time (109/124), inadequate training in the research process (40/124), inadequate supervision (31/124), inadequate financial resources (25/124) and lack of research continuity (11/124). Of the registrars sampled, 67.7% (84/124) believed research to be a valuable component of training. An overwhelming percentage (93.5%, 116/124) proposed a dedicated research block of time as a potential solution to overcoming the challenges encountered. Further proposals included attending a course in research methodology (79/124), supervision by a faculty member with an MMed or higher postgraduate degree (73/124), and greater research exposure as an undergraduate (56/124). No statistically significant differences were found between the perceptions of the researchexperienced and research-naive groups.Conclusions. Challenges facing surgical registrars in their efforts to complete their research projects were identified and solutions to these problems proposed. It is heartening that respondents have suggested solutions to the problems they encounter, and view research as an important component of their careers

Systematic investigation of the influence of electronic substituents on dinuclear gold( i ) amidinates: synthesis, characterisation and photoluminescence studies

Dinuclear gold(I) compounds are of great interest due to their aurophilic interactions that influence their photophysical properties. Herein, we showcase that gold–gold interactions can be influenced by tuning the electronic properties of the ligands. Therefore, various para substituted (R) N,N′-bis(2,6-dimethylphenyl)formamidinate ligands (pRXylForm; Xyl = 2,6-dimethylphenyl and Form = formamidinate) were treated with Au(tht)Cl (tht = tetrahydrothiophene) to give via salt metathesis the corresponding gold(I) compounds [pRXylForm$_2$Au$_2$] (R = –OMe, –Me, –Ph, –H, –SMe, and –CO$_2$Me). All complexes showed intense luminescence properties at low temperatures. Alignment with the Hammett parameter σ$_p$ revealed the trends in the $^1$H and $^{13}$C NMR spectra. These results showed the influence of the donor–acceptor abilities of different substituents on the ligand system which were confirmed with calculated orbital energies. Photophysical investigations showed their lifetimes in the millisecond range indicating phosphorescence processes and revealed a redshift with the decreasing donor ability of the substituents in the solid state

ICT INVESTMENT EFFECTIVENESS IN THE SOUTH AFRICAN POST OFFICE: RECONSIDERING THE APPROACHES OF THE PAST 20 YEARS

Organisations have invested and continue to invest considerable resources in Information and Communication Technology (ICT). Much of this investment is made on the basis of guarantee than an expected return will occur. This study presents the results of an empirical study of the impact of ICT investment on performance at the South African Post office (SAPO). Six years of historical data, from 2005 to 2010, were obtained from the Chief Information Officer (CIO) of the SAPO and analysed. This included appropriate IT data and financial data from the organisation’s financial statements and balance sheet. ICT investments were tested against financial performance indicators such as return on ICT investment, operating leverage, turnover growth, net profit, organisational risk, IT cost efficiency ratio and IT efficiency ratio. Within the period studied, it was observed that ICT investments at SAPO were negatively correlated with most of the financial indicators such as return on ICT investment, operating leverage, turn-over growth, net profit, organisational risk and IT efficiency ratio. This study therefore suggests that ICT investments at SAPO for the mentioned period did not have desirable impact on financial performance of the organisation. In order to realise tangible financial benefits of the ICT investments at SAPO, the research results suggest that a longer period needs to be considered, and should also include like non-technological determinants such as competence and experience levels of IT personnel, alignment of IT strategy with business strategy and business process re-engineering to suit new systems needs to be considered too prior to making any investments in ICT

Bright Luminescence in Three Phases—A Combined Synthetic, Spectroscopic and Theoretical Approach

Combining phase-dependent photoluminescence (PL) measurements and quantum chemical calculations is a powerful approach to help understand the influence of the molecular surroundings on the PL properties. Herein, a phosphine functionalized amidinate was used to synthesize a recently presented bimetallic gold complex, featuring an unusual charge separation. The latter was subsequently used as metalloligand to yield heterotetrametallic complexes with an Au-M-M-Au “molecular wire” arrangement (M=Cu, Ag, Au) featuring metallophilic interactions. All compounds show bright phosphorescence in the solid state, also at ambient temperature. The effect of the molecular environment on the PL was studied in detail for these tetrametallic complexes by comparative measurements in solution, in the solid state and in the gas phase and contrasted to time-dependent density functional theory computations

Books

Oral cancer Oral Cancer: Epidemiology, Etiology and Pathology. Ed. by Colin Smith, Jens Pindborg and W. H. Binnie. Pp. ix + 106. Illustrated. R183,30. USA: Hemisphere. 1990.HPV and cervical cancer Human Papillomavirus and Cervical Cancer. Ed. by N. Munoz, F. X. Bosch and O. M. Jensen. Pp. xii + 155. Illustrated. France: International Agency for Research on Cancer. 1989.Child health Child Health in a Multicultural Society. Ed. by John Black. Pp. 75. Illustrated. £7 (including postage). London: BMJ. 1989. (Available also from Libriger Book Distributors).Merck manual of geriatics Merck Manual of Geriatrics. Ed. by William B. Abrams The Andrew J. Fletcher. Pp. xxii + 1267. Illustrated. RI4,50. and I: Merck. 1990. USALiver disease Progress in Liver Diseases. Vol 9. Ed. by Hans Popper and Fenton Schaffner. Pp. xv + 750. Illustrated. RllO. England: Harcourt Brace Jovanovich. 1990.Clinical dietetics and nutrition Clinical Dietetics and Nutrition. 3rd ed. Ed. by F. P. Antia. Pp. xvi +438. Illustrated. Oxford: Oxford University Press. 1989.Atlas of human anatomy Wolf-Heidegger's Atlas of Human Anatomy. Ed. by H. F. Frick, B. Kummer and R. V. Putz. pp. viii + 599. £(j(J. Basel: Karger. 1990.Health system decentralisation Health System Decentralization. Ed. by A. Mills, J. P. Vaughan, D. L. Smith and I. Tabibzadcll. pp. 151. Illustrated. SFr. 26. Geneva: World Health Organisation. 1990.Handbook of occupational medicine Handbook of Occupational Medicine. Ed. by Robert J. McCunney. Pp. xxiii + 510. Illustrated. Boston: Little, Brown. 1988.Leukaemia Leukaemia. 5th ed. Ed. by Edward S. Henderson and T. Andrew Lister. Pp. vii + 821. Illustrated. RHO. Kent: Harcoun Brace Jovanovich. 1990

Palpable pediatric thyroid abnormalities – diagnostic pitfalls necessitate a high index of clinical suspicion: a case report

A 12-year-old girl presented with a 4 year history of an enlarged, firm thyroid gland. On exam, her thyroid was firm and fixed and an enlarged cervical lymph node was palpable as well. Though a thyroid ultrasound prior to referral was read as thyroiditis, clinical suspicion for thyroid carcinoma mandated continued investigation. The diagnosis of papillary thyroid cancer was established and her workup revealed lymph node metastases as well as a tremendous burden of pulmonary metastases. Pediatric thyroid cancer is extremely rare, but often presents with aggressive disease. Palpable thyroid abnormalities in an individual under 20-years-old should be viewed with suspicion and should be thoroughly investigated to rule out malignancy even in the face of negative diagnostic procedures. Though pediatric papillary thyroid cancer often presents with loco-regional and even distant metastatic disease, mortality rates in follow-up for as long as 20 years are very favorable

Scattering length of the ground state Mg+Mg collision

We have constructed the X 1SIGMAg+ potential for the collision between two ground state Mg atoms and analyzed the effect of uncertainties in the shape of the potential on scattering properties at ultra-cold temperatures. This potential reproduces the experimental term values to 0.2 inverse cm and has a scattering length of +1.4(5) nm where the error is prodominantly due to the uncertainty in the dissociation energy and the C6 dispersion coefficient. A positive sign of the scattering length suggests that a Bose-Einstein condensate of ground state Mg atoms is stable.Comment: 15 pages, 3 figures, Submitted Phys. Rev.

Evolution of electronic and ionic structure of Mg-clusters with the growth cluster size

The optimized structure and electronic properties of neutral and singly charged magnesium clusters have been investigated using ab initio theoretical methods based on density-functional theory and systematic post-Hartree-Fock many-body perturbation theory accounting for all electrons in the system. We have systematically calculated the optimized geometries of neutral and singly charged magnesium clusters consisting of up to 21 atoms, electronic shell closures, binding energies per atom, ionization potentials and the gap between the highest occupied and the lowest unoccupied molecular orbitals. We have investigated the transition to the hcp structure and metallic evolution of the magnesium clusters, as well as the stability of linear chains and rings of magnesium atoms. The results obtained are compared with the available experimental data and the results of other theoretical works.Comment: 30 pages, 10 figures, 3 table