The Egyptian Cardiothoracic Surgeon (ECTS - E-Journal)
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Work and family trajectories: Changes across cohorts born in the first half of the 20th century
No full textThis paper deals with the relationship between family formation and employment in older cohorts of the English population born between 1916 and 1957. Based on retrospective life history data of the English Longitudinal Study of Ageing (ELSA) and using sequence and cluster analyses, we explore three dimensions in particular: employment, marital status, and having children, and the extent to which individuals’ life course trajectories on these three dimensions vary across cohorts, gender, and level of education. While the majority of men followed a trajectory of marriage and family formation with a (relatively) continuous career, the family-work trajectories of women varied noticeably from one cohort to the next, including increased labour market participation combined with fewer and shorter breaks from work to care for children. While the current perception is that the so-called ‘baby boomer’ generation born soon after World War Two was path-breaking in terms of life course innovations, our findings are not compatible with the assumption of a single cohort being particularly pioneering
Systemic glucocorticoid therapy and adrenal insufficiency in adults: a systematic review
No full textOwner Project Capabilities for Infrastructure Development:A Review and Development of the Strong Owner Concept
No full textResearch on the management of major projects is one of the main themes of Peter Morris work. We address this theme in the context of transportation infrastructure projects and focus in particular on the contribution of the strong owner to project performance. After defining the strong owner concept, we will suggest that the theoretical literature on dynamic capabilities can be the source of deeper insight into the strong owner and will thereby develop the concept of owner project capabilities. The paper will then present a framework generated from a review of the existing literature complemented by pilot empirical research which provides the basis for a research agenda on the role of the owner of the infrastructure assets in achieving high performance on transportation infrastructure projects. In discussion, the paper suggests that the framework developed is applicable to a wider variety of major projects and programmes
Bacterial Diversity in the Hyperalkaline Allas Springs (Cyprus), a Natural Analogue for Cementitious Radioactive Waste Repository
No full textThe biogeochemical gradients that will develop across the interface between a highly alkaline cementitious geological disposal facility for intermediate level radioactive waste and the geosphere are poorly understood. In addition, there is a paucity of information about the microorganisms that may populate these environments and their role in biomineralization, gas consumption and generation, metal cycling, and on radionuclide speciation and solubility. In this study, we investigated the phylogenetic diversity of indigenous microbial communities and their potential for alkaline metal reduction in samples collected from a natural analogue for cementitious radioactive waste repositories, the hyperalkaline Allas Springs (pH up to 11.9), Troodos Mountains, Cyprus. The site is situated within an ophiolitic complex of ultrabasic rocks that are undergoing active low-temperature serpentinization, which results in hyperalkaline conditions. 16S rRNA cloning and sequencing showed that phylogenetically diverse microbial communities exist in this natural high pH environment, including Hydrogenophaga species. This indicates that alkali-tolerant hydrogen-oxidizing microorganisms could potentially colonize an alkaline geological repository, which is predicted to be rich in molecular H2, as a result of processes including steel corrosion and cellulose biodegradation within the wastes. Moreover, microbial metal reduction was confirmed at alkaline pH in this study by enrichment microcosms and by pure cultures of bacterial isolates affiliated to the Paenibacillus and Alkaliphilus genera. Overall, these data show that a diverse range of microbiological processes can occur in high pH environments, consistent with those expected during the geodisposal of intermediate level waste. Many of these, including gas metabolism and metal reduction, have clear implications for the long-term geological disposal of radioactive waste
The CATFISH study protocol:an evaluation of a water fluoridation scheme
No full textBACKGROUND: Tooth decay is the commonest disease of childhood. We have known for over 90 years that fluoride can prevent tooth decay; it is present in nearly all toothpastes and can be provided in mouthwashes, gels and varnishes. The oldest method of applying fluoride is via the water supply at a concentration of 1 part per million. The two most important reviews of water fluoridation in the United Kingdom (the York Review and MRC Report on water fluoridation and health) concluded that whilst there was evidence to suggest water fluoridation provided a benefit in caries reduction, there was a need to improve the evidence base in several areas.METHODS/DESIGN: This study will use a natural experiment to assess the incidence of caries in two geographical areas, one in which the water supply is returned to being fluoridated following a discontinuation of fluoridation and one that continues to have a non-fluoridated water supply. The oral health of two discrete study populations will be evaluated - those born 9 months after the water fluoridation was introduced, and those who were in their 1st year of school after the introduction of fluoridated water. Both populations will be followed prospectively for 5 years using a census approach in the exposed group along with matched numbers recruitment in a non-exposed control. Parents of the younger cohort will complete questionnaires every 6 months with child clinical examination at ages 3 and 5, whilst the older cohort will have clinical examinations only, at approximately 5, 7 and 11 years old.DISCUSSION: This project provides a unique opportunity to conduct a high quality evaluation of the reintroduction of a water fluoridation scheme, which satisfies the inclusion criteria stipulated by the York systematic review and can address the design issues identified in the MRC report. The research will make a major contribution to the understanding of the costs and effects of water fluoridation in the UK in the 21st Century. Its findings will help inform UK policy on this important public health intervention and may have a significant impact on public health policy in other developed countries. There is currently true equipoise in relation to the effectiveness of water fluoridation in contemporary populations and while the biological plausibility is well established, there is a need to examine impact on the changing epidemiological status of dental decay.</p
New mechanism of load introduction into concrete-filled steel tubular column
No full textThis paper presents the results of new load-introduction tests and numerical simulations to investigate the mechanism of load introduction from shear connections to concrete-filled steel tubular (CFST) columns, and the effectiveness of changing different construction details. The results of the tests have confirmed the authors’ recently proposed new load introduction mechanism, obtained from an extensive numerical study. In the new load introduction mechanism, the connection load is introduced to the concrete core via the column length above and within the connection or the cap plate on top of the column. There is no limit to the load introduction length above the connection. Below the connection, there is transfer of forces from the steel tube to the concrete core, but the total force in the column remains unchanged. This load introduction mechanism is different from that assumed in the various current design codes, including Eurocode 4 and AISC Specification. This study has an important implication on CFST column design: using shear connectors below the connection is ineffective in increasing CFST column strength
How bad can a good enough parent be?
No full textAlmost everyone accepts that parents must provide a good enough upbringing in order to retain custodial rights over children, but little has been said about how that level should be set. In this paper, I examine ways of specifying a good enough upbringing. I argue that the two dominant ways of setting this level, the Best Interests and Abuse and Neglect Views, are mistaken. I defend the Dual Comparative View, which holds that an upbringing is good enough when shortfalls from the best alternative upbringing in terms of the child's interests are no more significant than the parents' interest
Customised aberration-controlling contact lenses for keratoconus: the story so far
No full textPurpose: Technological advances have led to the design of customised, aberration-controlling soft contact lenses for keratoconic patients. These lenses are designed to reduce the magnitudes of higher-order aberrations induced through corneal apical protrusion, such as coma, trefoil and spherical aberration. This presentation reviews the limitations of such customised soft contact lens corrections. Methods: Mathematical computations were used to model the magnitude of superfluous aberrations induced through typical ‘on-eye’ rotations or translations of customised soft lenses, specifically designed for patients with mild, moderate and severe keratoconus. Results: The tolerances for on-eye lens displacements were found to be very restrictive. For optimal optical performance, lens rotations should be minimised to less than 8 degrees for patients with mild to moderate keratoconus, yet ideally less than 4 degrees for patients with severe keratoconus. Equally, vertical lens displacements ought to be minimised to 0.10 mm, or less. Conclusions: Compared to conventional, flat-fitting rigid gas-permeable (RGP) contact lenses, customised soft lenses may offer keratoconic patients improved comfort and a reduced risk of developing RGP lens-induced apical scarring. However, the typical on-eye movements of customised soft lenses are likely to hinder their optimal optical performance, thereby limiting their use to patients with early to mild keratoconus only
Raman Spectroscopy of Highly Pressurized Graphene Membranes
No full textRaman spectroscopy is an ideal tool for characterization of strained graphene. Biaxial strain, in particular, allows for more reliable calculation of the Gruneisen parameters than uniaxial strain. However, the application of biaxial strain is rather difficult to achieve experimentally, so all previous studies reported on graphene subjected to relatively small biaxial strains (0.1-1%), in contrast to uniaxial strain above 10%. Here we report a simple fabrication technique to produce pressurized and stable graphene membranes that can support differential pressures up to 14 bar, corresponding to a reversible strain up to ~2%. We find that the Grüneisen parameters remain constant even for the largest strains achieved, in agreement with theoretical predictions. However, for strains above 1%, a distinctive broadening of both the G and 2D peaks was observed for biaxial strain. We attribute this to nanoscale variations of strain in the membrane within an area comparable with the laser spot size