Stereoscopic dual-energy X-ray imaging for target materials identification

An experimental stereoscopic dual-energy X-ray imaging system is employed to extract the effective atomic number from a target layer of multiple layers of different materials. Further work investigated utilising stereoscopic parallax data to calculate layer thickness which, when combined with dual-energy data, enables the mass density of the target to be established. The research is part of an ongoing programme of work in collaboration with the UK Home Office to discriminate and identify substances in X-ray security screening applications. Initial work utilised a basis materials decomposition (BMD) technique to compute the characteristic angle, an indicator of atomic composition. The problem of overlapping materials masking a target was solved by further refinement of the BMD method, which can also be used determine mass density when layer thickness is known. The empirical investigation concentrated on computing the characteristic angle for different target materials in various overlapping arrangements. Also, the results from employing manually extracted parallax data to calculate the thickness of a target material are presented together with the resultant estimation of the targets' mass density.     

Modeling and simulation of mixed traffic on a prioritized shared medium

Network access systems (NAS) such as digital loop carriers (DLC) are increasingly utilizing a shared medium, such as Hybrid Fiber Coax (HFC) to provide point‐to‐multi‐point access from the public switched telephone network (PSTN) to the end user (consumer). New services, such as direct access to the packet switched network (PSN, WWW) have been added to DLC equipment in such a way as to provide for a prioritized set of services over a shared medium in an effort to take advantage of otherwise unused bandwidth. The introduction of such services requires the modeling and analysis of these network access systems. This becomes complex when considering the variability in different service type traffic characteristics. This work identifies a traffic engineering problem of prioritized circuit switched and packet switched (PSTN/PSN) traffic over the same shared medium as it may relate to “perceived” quality of service (QoS). Copyright © 2002 John Wiley & Sons, Ltd.     

The Bjornstad syndrome (sensorineural hearing loss and pili torti) disease gene maps to chromosome 2q34-36

We report that the Bjornstad syndrome gene maps to chromosome 2q34-36. The clinical association of sensorineural hearing loss with pili torti (broken, twisted hairs) was described >30 years ago by Bjornstad; subsequently, several small families have been studied. We evaluated a large kindred with Bjornstad syndrome in which eight members inherited pili torti and prelingual sensorineural hearing loss as autosomal recessive traits. A genomewide search using polymorphic loci demonstrated linkage between the disease gene segregating in this kindred and D2S434 (maximum two-point LOD score = 4.98 at theta = 0). Haplotype analysis of recombination events located the disease gene in a 3-cM region between loci D2S1371 and D2S163. We speculate that intermediate filament and intermediate filament-associated proteins are good candidate genes for causing Bjornstad syndrome.     

Lipopolysaccharide induces sickness behaviour in rats by a vagal mediated mechanism

A 52-year-old man was hospitalized for a right adrenal tumor which had been incidentally found by abdominal CT scan for examination of colon cancer. Laboratory and endocrine findings were within the normal limits except for increased urinary concentrations of noradrenaline and dopamine. Adrenal angiography revealed that the feeding artery of the tumor was the inferior suprarenal artery. Adrenal venous blood sampling studies detected no abnormalities in the concentrations of catecholamine, cortisol or aldosterone. Right adrenalectomy was performed and the tumor was histologically diagnosed as ganglioneuroma. Ganglioneuroma is a benign tumor originating from the sympathetic nerve ganglion. The adrenal origin of the tumor is relatively rare and 60 cases of adrenal ganglioneuroma including our case have been reported in Japan.     

Calcium antagonists and mortality risk in men and women with hypertension in the Framingham Heart Study

BACKGROUND: Several recent studies have suggested that calcium antagonist drugs, which are widely used for the treatment of hypertension, are associated with increased risk of cardiovascular disease. These studies have cast doubts on the long-term safety of calcium antagonists. OBJECTIVE: To examine the association of calcium antagonist use with mortality in subjects with hypertension followed up in the Framingham Heart Study. SUBJECTS AND METHODS: We stratified 3539 subjects (mean+/-SD age, 64+/-13 years) from the Framingham Heart Study who had hypertension at routine clinic examinations, according to the use of calcium antagonists and presence of coronary heart disease at the baseline examination. At each follow-up examination (every 2-4 years), subjects were reclassified with regard to the use of calcium antagonists. The end point of the study was all-cause mortality. Hazard ratios and 95% confidence intervals associated with the use of calcium antagonists were obtained using Cox proportional hazards regression models. RESULTS: There were 970 deaths during follow-up. Hazard ratios for mortality associated with the use of calcium antagonists were 0.93 (95% confidence interval, 0.72-1.21; P=.59) for subjects with hypertension without coronary heart disease, and 0.92 (95% confidence interval, 0.69-1.24; P=.58) for those with coronary heart disease at baseline. All models were adjusted for age, sex, current smoking, systolic and diastolic blood pressure, use of beta-blockers, and use of other antihypertensive medications. CONCLUSIONS: In this cohort of 3539 subjects with hypertension there were no differences in mortality among subjects with hypertension using a calcium antagonist compared with those who were not. Results were similar among subjects with hypertension with and without coronary heart disease. The results of ongoing long-term, randomized clinical trials will provide more definitive data on the safety of calcium antagonists.     

Factors influencing the selection of analgesia in spontaneously labouring nulliparous women at term

It is the purpose of this study to compare the prognostic value of the Herring classification (lateral pillar) with that of the Catterall classification. The material is constituted by 45 patients affected with Perthes' disease and reviewed an average of 24 years after onset. At follow-up the hips were divided into three classes based on joint congruency as suggested by Stulberg. The Catterall classification demonstrated overall a better predictive value for the Herring system. Instead, the most satisfactory reproducibility seems to be that of Herring: 80% as compared to 42% for the Catterall classification.