Homogeneous Gold Catalysis through Relativistic Effects: Addition of Water to Propyne

In the catalytic addition of water to propyne the Au(III) catalyst is not stable under non-relativistic conditions and dissociates into a Au(I) compound and Cl2. This implies that one link in the chain of events in the catalytic cycle is broken and relativity may well be seen as the reason why Au(III) compounds are effective catalysts.Comment: 12 pages, 3 figures, 1 tabl

Job Stress among Female Residents during Postgraduate Training at a University Hospital in Karachi, Pakistan

Background: Postgraduate medical training is a stressful experience for both male and female doctors but previous studies have shown that stress might be more prevalent amongst female residents. Since women make up 70-80% of medical graduates in Pakistan we conducted this study to determine the prevalence of stress among female residents during postgraduate training and identify the most common stressors. Methodology: All female residents enrolled in postgraduate training programmes at the Aga Khan University meeting the inclusion criteria were recruited and informed written consent was obtained. Job Stress Inventory (JSI) was used to identify symptoms and sources of job stress. A cut-off value of \u3e25 was used to indicate job stress. Results: A total of 154 female residents met the inclusion criteria. The response rate of the survey was 77%. Sixty one residents scored 26 or more on the JSI, indicating the presence of job stress. The three most common causes cited for job stress were, lack of control, environmental factors and workplace politics. Conclusion: Our study indicates a high prevalence of stress among female residents, independent of the marital status, number of children, the chosen specialty or the level of training. We suggest that programme directors and supervising faculty acknowledge the need for change in the training programmes refraining from favoritism and the need for politics towards constructive feedback based on merit and hard work and allow the residents to have more control over their working environment

Are non-diabetic women with abnormal glucose screening test at increased risk of pre-eclampsia, macrosomia and caesarian birth?

To determine, in non-diabetic women, the relationship of abnormal glucose screening test, with the incidence of pre-eclampsia, macrosomia and caesarian delivery, from 1988-92, 5646 consecutive women attending antenatal clinic were screened with a glucose challenge test (GCT) on their first visit (usually at 16-20 weeks); those with risk factors i.e., history of unexplained perinatal loss, macrosomia or family member with diabetes and an initial abnormal screening test were rescreened at 28-32 weeks, In 482 cases the GCT was abnormal (plasma glucose value was \u3e140 mg% 2 hours after 75g glucose challenge). Of these, 292 had one or more abnormal critical values at a 75g -3 hour oral glucose tolerance test (GTT) and they were treated to maintain euglycaemia. The rest (n=190) had no evidence of glucose intolerance with no abnormal values at the GTT. The subjects were divided into 3 groups based on GCT values; A, randomly selected subjects with a normal GCT (n=1000); B, those with abnormal GCT but normal GTT (n=190); and C, those with abnormal GTT (n=292). The variables studied were age, gravidity, parity, gestational age at delivery, pre-eclampsia, birth-weight and mode of delivery. The incidence of pre-eclampsia and caesarian birth varied, being the lowest in Group A (3.9% and 11.9% respectively) and then rising through group B (6.3% and 16.3% respectively) to the highest in Group C (12.6% and 26.0% respectively; test of linear trend, p\u3c0.05). For macrosomia, the incidence increased from Group A to B but there was a drop in Group C. The incidence of macrosomia was significantly higher for Group B as compared to A or C (9.5% and 3.3%,

The Potential Value of EGFR and P53 Immunostaining in Tumors of the Urinary Bladder

The expression of EGFR and p53 has not been adequately studied as a prognostic tool in urinary bladder tumors. We analyzed 74 bladder cancer samples from Egypt for EGFR and p53 expression using immunohistochemistry. The tumors were of different histological types, grades and clinical stages, and with established lymph node status. Almost 61% of the tumors showed positive membranous EGFR expression and 74.3% had positive nuclear staining of p53. Analysis of correlation of the IHC staining with clinical variables showed a significant correlation only between EGFR expression and histological type (p=0.002, ANOVA), in that the expression was higher in squamous cell carcinomas than in other histological types. There were no significant correlations between p53 or EGFR with the other clinicopathological variables, including age, sex, staging, grading, and lymph node status. Further studies are needed to determine if EGFR and p53 might be used as prognostic tools in bladder cancer

Role of the dielectric constant of ferroelectric ceramic in enhancing the ionic conductivity of a polymer electrolyte composite

The dispersal of high dielectric constant ferroelectric ceramic material Ba(0.7)Sr(0.3)TiO(3) (Tc~30 C) and Ba(0.88)Sr(0.12)TiO(3) (Tc~90 C) in an ion conducting polymer electrolyte (PEO:NH4I) is reported to result in an increase in the room temperature ionic conductivity by two orders of magnitude. The conductivity enhancememt "peaks" as we approach the dielectric phase transition of the dispersed ferroelectric material where the dielectric constant changes from ~ 2000 to 4000. This establishes the role of dielectric constant of the dispersoid in enhancing the ionic conductivity of the polymeric composites.Comment: 10 pages, 2 figure