Mode Conversion of Guided Waves by Defects in Pipes

The corrosion of pipework is a major problem for the oil and gas and petro-chemical industries. Large facilities operate hundreds of kilometres of pipes which may carry corrosive substances. General wall-thinning and localised pitting corrosion can occur both from the inside and the outside of pipe walls. A high proportion of these pipes are insulated, so that even the external defects cannot be detected by conventional NDE techniques without the expense of removing of the insulation

The Lamb Wave Inspection of Chemical Plant Pipework

Corrosion in pipework is a major problem, particularly in the oil, gas, chemical and petro-chemical industries. Since a high proportion of industrial pipelines are insulated, this means that even external corrosion cannot readily be detected without the removal of the insulation, which in most cases is prohibitively expensive. There is therefore an urgent need for the development of a quick, reliable method for the detection of corrosion under insulation (CUI)

Field Application of a Subunit Vaccine against an Enteric Protozoan Disease

Background: Coccidiosis is a major global veterinary health problem in intensively reared chickens. It is caused by apicomplexan parasites of the genus Eimeria. Principal Findings: A subunit vaccine composed of purified antigens from the gametocytes of Eimeria maxima was used to stimulate the production and transfer of maternal antibodies between breeding hens and their hatchlings. The vaccine was injected into hens twice before they began laying eggs. Immunization had no adverse affects on egg laying or health of the hens and resulted in high antibody levels throughout the life of the hens. Progeny of immunized hens excreted significantly less oocysts of various species of Eimeria in their faeces than chicks from unvaccinated hens. Furthermore, the offspring of vaccinated hens developed stronger natural immunity to Eimeria, so that they were resistant to challenge infection even at 8 weeks of age, well after all maternal antibodies had left their circulation. Field trials were conducted in South Africa, Brazil and Thailand, involving at least 1 million progeny of vaccinated hens and at least 1 million positive control birds (raised on feed containing anticoccidial drugs or immunized with a live vaccine) in each country. Additionally, trials were carried out in Israel involving 60 million progeny of vaccinated hens and 112 million positive control birds. There were no significant differences in growth rate, feed conversion ratios or mortality in the offspring of vaccinated hens compared with the positive control chickens in any of these countries regardless of different management practices, different breeds of chickens or climate. Conclusions: These results demonstrate that a vaccine composed of antigens purified from the gametocytes of Eimeria can be used safely and effectively to prevent the deleterious effects of coccidiosis. It is the first subunit vaccine against any protozoan parasite to be successfully applied on a commercial scale. © 2008 Wallach et al

Diabetes status and post-load plasma glucose concentration in relation to site-specific cancer mortality: findings from the original Whitehall study

ObjectiveWhile several studies have reported on the relation of diabetes status with pancreatic cancer risk, the predictive value of this disorder for other malignancies is unclear. Methods: The Whitehall study, a 25year follow-up for mortality experience of 18,006 men with data on post-challenge blood glucose and self-reported diabetes, allowed us to address these issues. Results: There were 2158 cancer deaths at follow-up. Of the 15 cancer outcomes, diabetes status was positively associated with mortality from carcinoma of the pancreas and liver, while the relationship with lung cancer was inverse, after controlling for a range of potential covariates and mediators which included obesity and socioeconomic position. After excluding deaths occurring in the first 10years of follow-up to examine the effect of reverse causality, the magnitude of the relationships for carcinoma of the pancreas and lung was little altered, while for liver cancer it was markedly attenuated. Conclusions: In the present study, diabetes status was related to pancreatic, liver, and lung cancer risk. Cohorts with serially collected data on blood glucose and covariates are required to further examine this area

Evaluation of the Workplace Environment in the UK, and the Impact on Users’ Levels of Stimulation

The purpose of this study is to evaluate a number of recently completed workplaces in the UK. The first aim is to assess the impact of various aspects of the workplace environment on users’ levels of stimulation. The body of previous research undertaken into the workplace environment, identified the aspects to be investigated. Samples of employees from the sixteen businesses were surveyed to determine their perceptions of the workplaces. The results were entered into a regression analysis, and the most significant predictors of perceived stimulation identified. The data also revealed a dramatic reduction in staff arousal levels from mornings to afternoons. Thus, there is a second aim to determine whether changes to significant aspects of the workplace environment during the day can counteract the reduction in users’ stimulation. Two further workplaces were studied to enable changes to be made over a 12-week period. A sample of employees completed questionnaires, and semi-structured interviews revealed the reasons behind the results. It was found that provision of artwork, personal control of temperature and ventilation and regular breaks were the most significant contributions to increasing stimulation after lunch; while user choice of layout, and design and décor of workspaces and break areas, were the most significant aspects at design stage

The Inspection of Chemical Plant Pipework Using Lamb Waves: Defect Sensitivity and Field Experience

Corrosion and pitting defects in pipework are major problems in the oil, chemical and other industries. These defects can occur at the outer or inner surface of the pipe and can lead to a serious loss of pipe wall thickness. As a high proportion of industrial pipelines are insulated, this means that even external corrosion cannot readily be detected without the removal of the insulation, which in most cases is prohibitively expensive.</p

5D gravity and the discrepant G measurements

It is shown that 5D Kaluza-Klein theory stabilized by an external bulk scalar field may solve the discrepant laboratory G measurements. This is achieved by an effective coupling between gravitation and the geomagnetic field. Experimental considerations are also addressed.Comment: 13 pages, to be published in: Proceedings of the 18th Course of the School on Cosmology and Gravitation: The gravitational Constant. Generalized gravitational theories and experiments (30 April-10 May 2003, Erice). Ed. by G. T. Gillies, V. N. Melnikov and V. de Sabbata, (Kluwer), 13pp. (in print) (2003

Blood pressure and site-specific cancer mortality: evidence from the original Whitehall study

Studies relating blood pressure to cancer risk have some shortcomings and have revealed inconsistent findings. In 17498 middle-aged London-based government employees we related systolic and diastolic blood pressure recorded at baseline examination (1967-1970) to the risk of cancer mortality risk at 13 anatomical sites 25 years later. Following adjustment for potential confounding and mediating factors, inverse associations between blood pressure and mortality due to leukaemia and cancer of the pancreas (diastolic only) were seen. Blood pressure was also positively related to cancer of the liver and rectum (diastolic only). The statistically significant blood pressure-cancer associations seen in this large-scale prospective investigation offering high power were scarce and of sufficiently small magnitude as to be attributable to chance or confounding

QuantiFERON®-TB gold in-tube performance for diagnosing active tuberculosis in children and adults in a high burden setting.

To determine whether QuantiFERON®-TB Gold In-Tube (QFT) can contribute to the diagnosis of active tuberculosis (TB) in children in a high-burden setting and to assess the performance of QFT and tuberculin skin test (TST) in a prospective cohort of TB suspect children compared to adults with confirmed TB in Tanzania. Sensitivity and specificity of QFT and TST for diagnosing active TB as well as indeterminate QFT rates and IFN-γ levels were assessed in 211 TB suspect children in a Tanzanian district hospital and contrasted in 90 adults with confirmed pulmonary TB. Sensitivity of QFT and TST in children with confirmed TB was 19% (5/27) and 6% (2/31) respectively. In adults sensitivity of QFT and TST was 84% (73/87) and 85% (63/74). The QFT indeterminate rate in children and adults was 27% and 3%. Median levels of IFN-γ were lower in children than adults, particularly children <2 years and HIV infected. An indeterminate result was associated with age <2 years but not malnutrition or HIV status. Overall childhood mortality was 19% and associated with an indeterminate QFT result at baseline. QFT and TST showed poor performance and a surprisingly low sensitivity in children. In contrast the performance in Tanzanian adults was good and comparable to performance in high-income countries. Indeterminate results in children were associated with young age and increased mortality. Neither test can be recommended for diagnosing active TB in children with immature or impaired immunity in a high-burden setting

Cardiorespiratory fitness, fatness and the acute blood pressure response to exercise in adolescence

Objective: Exaggerated exercise blood pressure (BP) is associated with cardiovascular risk factors in adolescence. Cardiorespiratory fitness and adiposity (fatness) areindependent contributors to cardiovascular risk, but their interrelated associationswith exercise BP are unknown. This study aimed to determine the relationships between fitness, fatness, and the acute BP response to exercise in a large birth cohort ofadolescents.Methods: 2292 adolescents from the Avon Longitudinal Study of Parents andChildren (aged 17.8 ± 0.4 years, 38.5% male) completed a sub-maximal exercisestep test that allowed fitness (VO2 max) to be determined from workload and heart rateusing a validated equation. Exercise BP was measured immediately on test cessationand fatness calculated as the ratio of total fat mass to total body mass measured byDXA.Results: Post-exercise systolic BP decreased stepwise with tertile of fitness (146(18); 142 (17); 141 (16) mmHg) but increased with tertile of fatness (138 (15); 142(16); 149 (18) mmHg). In separate models, fitness and fatness were associated withpost-exercise systolic BP adjusted for sex, age, height, smoking, and socioeconomicstatus (standardized β: −1.80, 95%CI: −2.64, −0.95 mmHg/SD and 4.31, 95%CI:3.49, 5.13 mmHg/SD). However, when fitness and fatness were included in thesame model, only fatness remained associated with exercise BP (4.65, 95%CI: 3.69,5.61 mmHg/SD).Conclusion: Both fitness and fatness are associated with the acute BP response to exercise in adolescence. The fitness-exercise BP association was not independent of fatness, implying the cardiovascular protective effects of cardiorespiratory fitness mayonly be realized with more favorable body composition