31 research outputs found
Acquisition and Processing of Cerebral Blood Flow Data with a M;ultichannel Analyser and Microcomputer
The method of the determination of cerebral blood flow in dogs with radio-isotopes to evaluate ethrane as a new anaesthetic agent is described, as well as the use of a multichannel analyser and the programmes developed for the analysis of data in a conversational mode. Preliminary results of the use of the computer programme are presented
Comparación de distintas estrategias para la predicción de muerte a corto plazo en el paciente anciano infectado
Objective. The aim of this study was to determine the utility of a post hoc lactate added to SIRS and qSOFA score to predict 30-day mortality in older non-severely dependent patients attended for infection in the Emergency Department (ED).
Methods. We performed an analytical, observational, prospective cohort study including patients of 75 years of age or older, without severe functional dependence, attended for an infectious disease in 69 Spanish ED for 2-day three seasonal periods. Demographic, clinical and analytical data were collected. The primary outcome was 30-day mortality after the index event.
Results. We included 739 patients with a mean age of 84.9 (SD 6.0) years; 375 (50.7%) were women. Ninety-one (12.3%) died within 30 days. The AUC was 0.637 (IC 95% 0.587-0.688; p= 2 and 0.698 (IC 95% 0.635- 0.761; p= 2. Comparing receiver operating characteristic (ROC) there was a better accuracy of qSOFA vs SIRS (p=0.041). Both scales improve the prognosis accuracy with lactate inclusion. The AUC was 0.705 (IC95% 0.652-0.758; p<0.001) for SIRS plus lactate and 0.755 (IC95% 0.696-0.814; p<0.001) for qSOFA plus lactate, showing a trend to statistical significance for the second strategy (p=0.0727). Charlson index not added prognosis accuracy to SIRS (p=0.2269) or qSOFA (p=0.2573).
Conclusions. Lactate added to SIRS and qSOFA score improve the accuracy of SIRS and qSOFA to predict short-term mortality in older non-severely dependent patients attended for infection. There is not effect in adding Charlson index
Clinical Evaluation of a New Non-depolarising Muscle Relaxant
Certain pharmacological effects of a new non-depolarising muscle relaxant, AH 8165 (Glaxo), were studied in 50 patients. The adequate dose for muscle relaxation onset of action, duration of effect and reversibility with cholinesterase agents, were established. Changes in blood pressure, heart rate, intra-ocular pressure, blood gases and acid-base values were measured. In comparison with pancuronium bromide, the onset of action was much more rapid, but the duration of effect was the same. Reversal with anticholinesterase agents was good, and no residual hypoventilation could be detected postoperatively
THE IMPORTANCE OF THE CHANGING DEMOGRAPHIC PROFILE ON THE SUCCESS OF POST GRADUATE ACCOUNTING STUDENTS
A study was undertaken to determine which variables in the demographic profile of students at the University of South Africa (UNISA) influence academic performance in their first attempt at obtaining the Certificate in the Theory of Accountancy. An inferential research study on secondary data was performed to determine which of certain predictor variables, of the demographic profile, namely ‘age group’, ‘assessment language’, ‘previous institution’, ‘race’, ‘gender’ and ‘occupation’, can influence academic performance. ‘Gender’ and ‘occupation’, not having a statistically significant relationship with the outcome variable, were excluded from the multivariable analysis performed. The findings revealed that students younger than 25 years of age, who are assessed in their home language and complete their undergraduate studies at an institution other than the University of South Africa, have a greater chance of success. The odds for success of African, coloured and Indian students are however lower than those of white students. The research indicated a decline of 8% in the number of successful students from 2007 to 2009, which pose a tough challenge for the institution, which could possibly be addressed by support programmes and providing financial support students that are not at risk as indicated in the study
Molecular modelling of tantalum penta-halides during hydrolysis and oxidation reactions
The transition metals tantalum (Ta) and niobium (Nb), which are usually found together in nature, have similar chemical and physical properties, making their separation challenging. There are various methods available for the separation of these two metals, including reduction, fluorination, chlorination and solvent extraction (SX) (Ayanda and Adekola, 2011). In a recent study investigating the suitability of SX for the separation of Ta and Nb, it was shown that speciation data would be required to help explain the distribution data obtained. Since traditional speciation techniques cannot be readily applied for Ta and Nb, it was decided to determine the suitability of molecular modelling for this purpose. To investigate the suitability of modelling for this application a case study was selected where it was hypothesised that when TaF5 is dissolved in water, it could react stepwise with water to finally form tantalum penta-hydroxide (Ta(OH)5) and other oxyfluoride species including TaOF3. Due to the fact that literature on TaF5 reactions with water is limited, TaCl5 and its reactions was used to develop the model (method). As part of the model development and verification, DFT was used to calculate the energy needed for these reactions, comparing different functionals and basis sets. The validated model was then applied to TaF5 as a case study. From the results it was confirmed that the reaction of TaX5 (X = Cl or F) with water to form Ta(OH)5 and Ta2O5 is an endothermic reaction, while the formation of Ta(H2O)F5 and TaF4OH was exothermi
Molecular modelling of tantalum fluoride in sulphuric acid medium: a DFT study
During the solvent extraction (SX) experiments of tantalum (Ta) and niobium (Nb), the aqueous phase consisted of tantalum- and niobium penta-fluoride (Ta(Nb)F5), water (H2O) and sulphuric acid (H2SO4), which was contacted with an organic phase. In this study the aqueous phase used during SX was modelled by studying the interactions and resulting reactions of specifically TaF5 when it is contacted with H2O and H2SO4. Different functional and basis set combinations within density functional theory (DFT) were investigated. From previous modelling it was seen that by increasing the number of water molecules, the reaction energy decreased due to molecule stabilisation (hydrogen bonding) and subsequently a 1:1:10 metal:acid:water ratio were used.
Results showed that the deprotonation of H2SO4 was exothermic, leading to the formation of HSO4−. Furthermore, from the various reactions and geometries between TaF5, H2SO4 and H2O investigated, it was observed that only four species would be available in the aqueous phase during solvent extraction, namely TaF5·H2O in water or diluted acid medium, TaF4·HSO4 in a concentrated H2SO4 medium and TaF4OH or TaF3OH·HSO4 if the aqueous phase was aged. From the results obtained a reaction mechanism that might occur during SX of TaF5 was predicte
Experience with the Bjork-Shiley Prosthetic Valve
Gratifying results were obtained with the Bjork-Shiley prosthesis in this series of 63 patients. The surgical mortality of the entire series was 7,9%. Late morbidity was negligible. Of 8 patients who had right-sided valvular replacement, 1 died on the operating table, and the 7 surviving patients did extremely well, with no late morbidity. We believe this to be a satisfactory prosthesis which can effectively be used for right-sided valvular replacement
Automated detection of neutralizing SARS-CoV-2 antibodies in minutes using a competitive chemiluminescence immunoassay.
The SARS-CoV-2 pandemic has shown the importance of rapid and comprehensive diagnostic tools. While there are numerous rapid antigen tests available, rapid serological assays for the detection of neutralizing antibodies are and will be needed to determine not only the amount of antibodies formed after infection or vaccination but also their neutralizing potential, preventing the cell entry of SARS-CoV-2. Current active-virus neutralization assays require biosafety level 3 facilities, while virus-free surrogate assays are more versatile in applications, but still take typically several hours until results are available. To overcome these disadvantages, we developed a competitive chemiluminescence immunoassay that enables the detection of neutralizing SARS-CoV-2 antibodies within 7 min. The neutralizing antibodies bind to the viral receptor binding domain (RBD) and inhibit the binding to the human angiotensin-converting enzyme 2 (ACE2) receptor. This competitive binding inhibition test was characterized with a set of 80 samples, which could all be classified correctly. The assay results favorably compare to those obtained with a more time-intensive ELISA-based neutralization test and a commercial surrogate neutralization assay. Our test could further be used to detect individuals with a high total IgG antibody titer, but only a low neutralizing titer, as well as for monitoring neutralizing antibodies after vaccinations. This effective performance in SARS-CoV-2 seromonitoring delineates the potential for the test to be adapted to other diseases in the future