Resection of a chest chondrosarcoma invading the spine and the aorta

A 34-year-old man presented with a large chondrosarcoma of the chest invading six ribs and the vertebral bodies of five adjacent thoracic vertebrae. En bloc resection of the tumor with six ribs, the anterior part of five vertebral bodies, and the thoracic aorta was performed through a thoracotomy and a paravertebral incision.     

Evaluation of patient dose for mammography in Pernambuco, Brazil

The aim of this study is to evaluate the incident air kerma (INAK) and the mean glandular dose (MGD) during mammography in Recife, North-east Brazil. The study was performed in three institutions: a private clinic (A), a public hospital (B) and a private hospital (C). The incident air kerma to mammography procedures were estimated using a standard breast phantom and the patient MGD, evaluated in the units B and C, was performed using the calibration of output method. This method involves the recording of the patient exposure parameters (kVp, mAs, filter) and the measurement of these parameters of the incident air kerma using a calibrated ionisation chamber. The results obtained showed that INAK for the standard breast phantom, in the institutions A, B and C, were 18.2, 9.4 and 8.5 mGy, respectively. The results of patient MGD values ranged from 0.23 to 7.46 mGy per film, and the MGD values per woman were between 8.23 and 40.6 mGy for the C institution and between 1.50 and 18.78 mGy for the B institution.     

The performance of commercial photodiodes for dosimetry in mammography

This paper reports the results of an investigation carried out to determine the suitability of using a commercially available photodiode for dosimetry in mammography thereby providing a low cost dosemeter with a direct reading of the radiation dose. A mammographic X-ray generator (Siemens Mammomat 1000) with tube potential in the 23-30 kV range and a constant potential X-ray generator (Pantak) with a W/Mo anode/filter combination were used in this study. The results showed that the photodiode response is highly linear within mammographic dose ranges and that the energy dependence was <3% at tube potentials of 25-30 kV. Good agreement was observed between the incident air kerma measured with both the photodiode and the ionization chamber. These results show the viability of using the photodiode as a dosemeter system in mammography.     

Volvulus of the sigmoid colon

The clinical presentation and treatment of 31 consecutive patients with sigmoid volvulus are reviewed. Nearly half of these patients had a history of mental illness and one-third of all patients were chronically constipated. The main clinical features of abdominal pain and gross abdominal distension had been present for an average of 8 days before presentation of the patient to hospital. The clinical diagnosis of sigmoid volvulus was not difficult but the presence of non-viable bowel was more difficult to establish. A silent abdomen was the most valuable indication of the presence of gangrenous bowel. Conservative measures, including sigmoidoscopy and therapeutic barium enema, successfully reduced the volvulus in half of the cases so treated. In those patients undergoing surgery the procedure associated with the lowest mortality was sigmoid resection with end-to-end anastomosis. The overall mortality was 35%.     

Efficient finite element formulation for geothermal heating systems. Part II: transient

This paper presents an extension to the work presented in Part I of this series of two articles to the transient case. Emphasis is placed on the development of a new model for heat flow in a double U‐shape vertical borehole heat exchanger and its thermodynamic interactions with surrounding soil mass. The discretization of the spatial‐temporal domain of the heat pipe model is done by the use of the space–time finite element technique in conjunction with the Petrov–Galerkin method and the finite difference method. The paper shows that the proposed model and the choice of the discretization technique, in addition to the utilization of a sequential numerical algorithm for solving the resulting system of non‐linear equations, have contributed in reducing significantly the required number of finite elements necessary for describing geothermal heating systems. Details of the mathematical derivations and comparison to experimental data are presented. Copyright © 2006 John Wiley & Sons, Ltd.     

Analysis of aflatoxin M1 in milk and yogurt and AFM1 reduction by lactic acid bacteria used in Lebanese industry

In this study a screening survey was undertaken to determine the presence and levels of aflatoxin M1 (AFM1) in locally produced dairy products. For this purpose, a total of 138 dairy samples (milk and yogurt) were analyzed to quantify AFM1 levels in these products. Results obtained showed that AFM1 was found in 40.62% and 32.81% of milk and yogurt samples respectively. The range of contamination levels varied between lower and higher than European regulation limit. Lactic acid bacteria (Lactobacillus bulgaricus and Streptococcus thermophilus) used in the Lebanese traditional industry were screened for their ability to reduce the level of AFM1. Due to the lack in data on the natural occurrence of AFM1 in Lebanese dairy products, the aim of this work was to report some information and to state these products according to EC regulations