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The thermal decomposition of 2-H-heptafluoropropane, CF3CHFCF3, at low pressure, heavily diluted in argon, has been studied over the temperature range 600−2000 °C using photoelectron spectroscopy. Comparison of the results obtained has been made with results of recent electronic structure calculations of possible decomposition pathways and results of a shock tube study. The most favored reaction thermodynamically, to produce CF3CFCF2+ HF, is found to be the main decomposition reaction at lower temperatures, 600−900 °C. At higher temperatures, 900−1200 °C, the decomposition reaction to give C2F4+ CF3H was found to become important. No evidence for CF3CHFCF3→ CF3CHF + CF3, a reaction expected to be important from a shock tube study, performed at much higher pressures, or for CF3CHFCF3→ CF3CF + CF3H was obtained, although for the latter reaction it is likely that CF3CF converts into C2F4under the conditions used before photoionization, in the ionization region of the photoelectron spectrometer. At higher temperatures C3F6decomposes to C2F4+ CF2, and C2F4decomposes to CF2. Ab initio calculations have been performed of the adiabatic and vertical ionization energies of possible primary pyrolysis products to assist assignment of the photoelectron spectra recorded for heated flowing gas samples. A comparison is made between the threshold photoelectron spectrum and the photoelectron spectrum of CF3CFCF2

In 2015, the second cycle of the CONCORD programme established global surveillance of cancer survival as a metric of the effectiveness of health systems and to inform global policy on cancer control. CONCORD-3 updates the worldwide surveillance of cancer survival to 2014.

Renal cell carcinoma (RCC) is a common malignancy following kidney transplantation. We describe RCC risk and examine RCC risk factors among US kidney recipients (1987–2010). The Transplant Cancer Match Study links the US transplant registry with 15 cancer registries. Standardized incidence ratios (SIRs) were used to compare RCC risk (overall and for clear cell [ccRCC] and papillary subtypes) to the general population. Associations with risk factors were assessed using Cox models. We identified 683 RCCs among 116 208 kidney recipients. RCC risk was substantially elevated compared with the general population (SIR 5.68, 95% confidence interval 5.27–6.13), especially for papillary RCC (SIR 13.3 versus 3.98 for ccRCC). Among kidney recipients, RCC risk was significantly elevated for blacks compared to whites (hazard ratio [HR] 1.50) and lower in females than males (HR 0.56). RCC risk increased with prolonged dialysis preceding transplantation (p-trend < 0.0001). Risk was variably associated for RCC subtypes with some medical conditions that were indications for transplantation: ccRCC risk was reduced with polycystic kidney disease (HR 0.54), and papillary RCC was increased with hypertensive nephrosclerosis (HR 2.02) and vascular diseases (HR 1.86). In conclusion, kidney recipients experience substantially elevated risk of RCC, especially for papillary RCC, and multiple factors contribute to these cancers.

US transplant centers are required to report cancers in transplant recipients to the transplant network. The accuracy and completeness of these data, collected in the Scientific Registry of Transplant Recipients (SRTR), are unknown. We compared diagnoses in the SRTR and 15 linked cancer registries for colorectal, liver, lung, breast, prostate and kidney cancers; melanoma; and non-Hodgkin lymphoma (NHL). Among 187 384 transplants, 9323 cancers were documented in the SRTR or cancer registries. Only 36.8% of cancers were in both, with 47.5% and 15.7% of cases additionally documented solely in cancer registries or the SRTR, respectively. Agreement between the SRTR and cancer registries varied (kappa = 0.28 for liver cancer and kappa = 0.52–0.66 for lung, prostate, kidney, colorectum, and breast cancers). Upon evaluation, some NHLs documented only in cancer registries were identified in the SRTR as another type of posttransplant lymphoproliferative disorder. Some SRTR-only cases were explained by miscoding (colorectal cancer instead of anal cancer, metastases as lung or liver cancers) or missed matches with cancer registries, partly due to recipients’ outmigration from catchment areas. Estimated sensitivity for identifying cancer was 52.5% for the SRTR and 84.3% for cancer registries. In conclusion, SRTR cancer data are substantially incomplete, limiting their usefulness for surveillance and research.

Global bifurcations of a perturbed planar-pendulum model for nonconservative systems capable of oscillation and rotation are analysed. The motions correspond to stable and unstable limit cycles following a saddle-node bifurcation. The parameter space may be divided into six regions of topologically distinct behavior. The model is applied to the phenomenon of flat-plate autorotation. Using experimental data, the model parameters are empirically fitted physical quantities. Predictions of angular velocity and the critical values of flow velocity and inertia for the onset of autorotation are in good agreement with the experimental observations of previous investigators. Copyright 1994, 1999 Academic Press

A system for the in-line measurement of puff-by-puff levels of carbon monoxide on a Filtrona 300 smoking machine during routine smoking of cigarette for tar and nicotine yields has been developed. The technique involves the introduction of a transducer into the suction line behind the Cambridge filter. This transducer comprises an electrochemical cell bridged by a pair of solenoid valves which are under the control of the cotton gate smoking terminator. These valves are actuated, other than at the butt mark, by an additional inductive timing switch on the crankshaft. Results using this technique compare well with results from existing off-Iine techniques such as gas-solid chromatography

This paper describes the observed dynamical behavior of a cantilevered pipe conveying fluid, an autonomous nonconservative (circulatory) dynamical system, limit-cycle motions of which, upon loss of stability via a Hopf bifurcation, interact with nonlinear motion-limiting constraints. This system was found to become chaotic at sufficiently high flow rates. Motions of the system, sensed by an optical tracking system, were analyzed by Fast Fourier Transform, autocorrelation, Poincare´ map, and delay embedding techniques, and the fractal dimension of the system, dc, was calculated. Values of dc = 1.03, 1.53, and 3.20 were obtained in the period-1, “fuzzy” period-2 and chaotic regimes of oscillation of the system. Based on these calculations, a four-dimensional analytical model was constructed, which was found to capture the essential dynamical features of observed behavior quite well.

In dataflow architectures, each dataflow node (i.e., operation) is typically executed on a single physical node. We are concerned with distributed data-intensive systems, in which each base (i.e., persistent) set of data has been declustered over many physical nodes to achieve load balancing. Because of large base set size, each operation is executed where the base set resides, and intermediate results are transferred between physical nodes. In such systems, each dataflow node is typically executed on many physical nodes. Furthermore, because computations are data-dependent, we cannot know until run time which subset of the physical nodes containing a particular base set will be involved in a given dataflow node. This uncertainty affects program loading, task activation and termination, and data transfer among the nodes.In this paper we focus on the problem of how a dataflow node in such an environment knows when it has received data from all the physical nodes from which it is ever going to receive. We call this the dataflow control problem. The interesting part of the problem is trying to achieve correctness efficiently. We propose three solutions to this problem, and compare them quantitatively by the metrics of total message traffic, message system throughput and data transfer response time.

In dataflow architectures, each dataflow operation is typically executed on a single physical node. We are concerned with distributed data-intensive systems, in which each base (i.e., persistent) set of data has been declustered over many physical nodes to achieve load balancing. Because of large base set size, each operation is executed where the base set resides, and intermediate results are transferred between physical nodes. In such systems, each dataflow operation is typically executed on many physical nodes. Furthermore, because computations are data-dependent, we cannot know until run time which subset of the physical nodes containing a particular base set will be involved in a given dataflow operation. This uncertainty creates several problems.We examine the problems of efficient program loading, dataflow—operation activation and termination, control of data transfer among dataflow operations, and transaction commit and abort in a distributed data-intensive system. We show how these problems are interrelated, and we present a unified set of mechanisms for efficiently solving them. For some of the problems, we present several solutions and compare them quantitatively.

J Proc. Instn Civ. An inverse method kinematic flow of Engrs Wat., Marit. modelling based on measured currents &Energy. 1994, 106, Sept., 249-258 G. J. M. Copeland, MA(Cantab),MSc, PhD m The development flowand dispersion of models for sea outfall design is reviewed briefly inorder to point out the rift between fieldmeasurements and the modelling process. Conventional models are unable to make use of measurements made within the model area except for calibration, while new remote sensing equipment is able to gather large quantities of current data located in a regular grid...

Pneumothorax is a very unusual presenting complication of a perforated abdominal viscus. We present two such cases. The importance of close scrutiny of chest radiographs taken for abdominal disease is stressed.