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The physical mechanisms governing flame anchoring have been examined in an effort to extend the range and maneuverability of compact, low-drag, air-breathing engines. Experiments were performed burning premixed methane and air in a planar dump combustor using reacting-flow particle image velocimetry as the primary diagnostic. Instantaneous two-dimensional images and vector fields were studied to determine changes in the fluid-chemical interactions of the shear layer as flame anchorability became more robust. Conditional averages of combustion products directed toward incoming reactants were evaluated to establish the connection to self-sustained combustion. A lean mixture of methane-air was used as a baseline, and the equivalence ratio and near-field counterflow were varied to affect anchorability. Dilatation was calculated as a marker for heat release and three-dimensionality. Operating points exhibiting a strong flux of products into reactants via a single coherent structure positioned downstream of the step were found to be most stable for flame anchoring. However, a counterflow level equal to 6.2 % of the primary stream by mass was found to match the characteristics of a single coherent structure while maintaining multiple structures in the mixing zone, effectively increasing heat release rates at a lower equivalence ratio. [ABSTRACT FROM AUTHOR]

The article presents abstracts on medical topics which include the audit of local atrial fibrillation prophylaxis and treatment guidelines and the difference between epidural and paravertebral analgesia for pneumonectomy.

Late malignancies have been discussed as a potential risk for growth factor mobilized donors of hematopoietic stem cells. Little is known about the incidence and potential risk factors. This single center retrospective cohort study evaluated all HLA-identical sibling pairs with hematopoietic stem cell transplantation (HSCT) for a hematological malignancy, treated from 1974 to 2001 at the University Hospital of Basel. Three hundred eighteen pairs were identified, 291 donors (92%) could be contacted. Median observation time was 13.8 years (range 5-32 years). Sixteen (5%) donors had developed a total of 18 tumors, 17 recipients a secondary tumor. According to the age- and sex-adapted cancer incidence, 3.3 tumors in male and 6.8 in female donors were expected, 3 (relative risk (RR): 0.91, 95% confidence interval: 0.19-2.66) and 4 (RR: 0.58, 95% confidence interval: 0.16-1.48), respectively, were found in donors between 0 and 49 years. Between 50 and 69 years, 4.5 tumors in males and 4.8 in females were expected, 5 (RR: 1.11, 95% confidence interval: 0.36-2.59) and 6 (RR: 1.23, 95% confidence interval: 0.45-2.67), respectively, were observed. Tumors do occur in donors of hematopoietic stem cells at least at the rate as expected in a normal population; whether incidence exceeds expected rates needs to be determined in larger international cohorts. [ABSTRACT FROM AUTHOR]

We report a new method of estimating the completeness of cancer registration, in which the proportions of unregistered patients are derived from the time distributions of three probabilities, each of which can be directly estimated from the registry's own data - the probabilities of survival, of registration of the cancer during the patient's life, and of the mention of cancer on the death certificate of a cancer patient who dies. This method allows completeness to be assessed routinely by factors such as age, sex, geographical area and tumour type. [ABSTRACT FROM AUTHOR]