Asset integrity case development for normally unattended offshore installations: Bayesian network modelling

This research proposes the initial stages of the application of Bayesian Networks in conducting quantitative risk assessment of the integrity of an offshore system. The main focus is the construction of a Bayesian network model that demonstrates the interactions of multiple offshore safety critical elements to analyse asset integrity. A NUI (Normally Unattended Installation) - Integrity Case will enable the user to determine the impact of deficiencies in asset integrity and demonstrate that integrity is being managed to ensure safe operations in situations whereby physical human to machine interaction is not occurring. The Integrity Case can be said to be dynamic as it shall be continually updated for an installation as the Quantitative Risk Analysis (QRA) data is recorded. This allows for the integrity of the various systems and components of an offshore installation to be continually monitored. The Bayesian network allows cause-effect relationships to be modelled through clear graphical representation. The model accommodates for continual updating of failure data

Emergency Caesarean Section: Influences on the Decision-to-Delivery Interval

RCOG/NICE guidelines recommend that, for fetal compromise in labour, delivery should be accomplished ideally within 30 minutes. In this study, we investigated the factors which affect the decision-to-delivery (DD) intervals for emergency caesareans. To achieve this, prospective data were collected for all grade 1 and 2 caesareans performed on a busy labour ward over 12 months. We found that the ratio of labouring women to midwives had a significant effect on the DD intervals, which were significantly prolonged when 1 : 1 care was not provided (P < 0.001). The observed effect resulted exclusively from a prolonged transfer time to theatre. General anesthesia use shortened the DD interval for grade 1 caesareans (P < 0.001) and was more likely to be used during the day shift (P < 0.009). We conclude that midwifery staffing levels and the form of anaesthesia employed influence on DD intervals for the most urgent caesarean sections

The Use of a Scoring System to Guide Thromboprophylaxis in a High-Risk Pregnant Population

Guidelines for thromboprophylaxis in pregnancy are usually based upon clinical observations and expert opinion. For optimal impact, their use must be attended by consistency in the advice given to women. In this observational study, we evaluated the performance of a scoring system, used as a guide for clinicians administering dalteparin to pregnant women at increased risk of venous thromboembolism. The work included 47 women treated with dalteparin prior to adoption of the scoring system and 58 women treated with dalteparin after its adoption. The indication for thromboprophylaxis was recorded in each case together with details of the regimen employed, obstetric, and haematological outcomes. The main outcome measure was to determine whether consistency improved after adoption of the scoring system. We also recorded the occurrence of any new venous thromboembolism, haemorrhage, the use of regional anaesthesia during labour, evidence of allergy, and thrombocytopenia. We found that use of the scoring system improved the consistency of advice and increased the mean duration of thromboprophylaxis. None of the subjects suffered venous thromboembolism after assessment using the scoring system. There was no increase in obstetric or anaesthetic morbidity when dalteparin was given antenatally period and no evidence of heparin-induced thrombocytopenia

Physical activity levels in locally advanced rectal cancer patients following neoadjuvant chemoradiotherapy and an exercise training programme before surgery: a pilot study

Background: The aim of this pilot study was to measure changes in physical activity level (PAL) variables, as well as sleep duration and efficiency in people with locally advanced rectal cancer (1) before and after neoadjuvant chemoradiotherapy (CRT) and (2) after participating in a pre-operative 6-week in-hospital exercise training programme, following neoadjuvant CRT prior to major surgery, compared to a usual care control group.Methods: We prospectively studied 39 consecutive participants (27 males). All participants completed standardised neoadjuvant CRT: 23 undertook a 6-week in-hospital exercise training programme following neoadjuvant CRT. These were compared to 16 contemporaneous non-randomised participants (usual care control group). All participants underwent a continuous 72-h period of PA monitoring by SenseWear biaxial accelerometer at baseline, immediately following neoadjuvant CRT (week 0), and at week 6 (following the exercise training programme).Results: Of 39 recruited participants, 23 out of 23 (exercise) and 10 out of 16 (usual care control) completed the study. In all participants (n = 33), there was a significant reduction from baseline (pre-CRT) to week 0 (post-CRT) in daily step count: median (IQR) 4966 (4435) vs. 3044 (3265); p &lt; 0.0001, active energy expenditure (EE) (kcal): 264 (471) vs. 154 (164); p = 0.003, and metabolic equivalent (MET) (1.3 (0.6) vs. 1.2 (0.3); p = 0.010). There was a significant improvement in sleep efficiency (%) between week 0 and week 6 in the exercise group compared to the usual care control group (80 (13) vs. 78 (15) compared to (69 ((24) vs. 76 (20); p = 0.022), as well as in sleep duration and lying down time (p &lt; 0.05) while those in active EE (kcal) (152 (154) vs. 434 (658) compared to (244 (198) vs. 392 (701) or in MET (1.3 (0.4) vs. 1.5 (0.5) compared to (1.1 (0.2) vs. 1.5 (0.5) were also of importance but did not reach statistical significance (p &gt; 0.05). An apparent improvement in daily step count and overall PAL in the exercise group was not statistically significant.Conclusions: PAL variables, daily step count, EE and MET significantly reduced following neoadjuvant CRT in all participants. A 6-week pre-operative in-hospital exercise training programme improved sleep efficiency, sleep duration and lying down time when compared to participants receiving usual care

The historical vanishing of the Blazhko effect of RR Lyr from GEOS and Kepler surveys

RR Lyr is one of the most studied variable stars. Its light curve has been regularly monitored since the discovery of the periodic variability in 1899. Analysis of all observed maxima allows us to identify two primary pulsation states defined as pulsation over a long (P0 longer than 0.56684 d) and a short (P0 shorter than 0.56682 d) primary pulsation period. These states alternate with intervals of 13-16 yr, and are well defined after 1943. The 40.8 d periodical modulations of the amplitude and the period (i.e. Blazhko effect) were noticed in 1916. We provide homogeneous determinations of the Blazhko period in the different primary pulsation states. The Blazhko period does not follow the variations of P0 and suddenly diminished from 40.8 d to around 39.0 d in 1975. The monitoring of these periodicities deserved and deserves a continuous and intensive observational effort. For this purpose we have built dedicated, transportable and autonomous small instruments, Very Tiny Telescopes (VTTs), to observe the times of maximum brightness of RR Lyr. As immediate results the VTTs recorded the last change of P0 state in mid-2009 and extended the time coverage of the Kepler observations, thus recording a maximum O-C amplitude of the Blazhko effect at the end of 2008, followed by the historically smallest O-C amplitude in late 2013. This decrease is still ongoing and VTT instruments are ready to monitor the expected increase in the next few years.Comment: 10 pages, 6 figures. Accepted for publication in MNRAS. Contents of appendix B may be requested to first autho

Lifespan cost analysis of alternatives to global sulphur emission limit with uncertainties

Following the updated global sulphur emission cap from 1 January 2020, shipowners are facing an increasing cost burden to comply with the new regulation in a tough shipping market. This research compares the lifespan costs of three main alternatives, all of which can satisfy the 2020 global sulphur emission regulation. A lifespan cost analysis model is built considering several cost items across the three alternatives, including the initial cost of investment, maintenance cost and fuel consumption cost. Two vessels with a capacity of 5000 and 10,000 TEUs are selected as case study vessels. The @risk software is utilized to conduct an uncertainty analysis with respect to the fuel price and the discount rate to test the three alternatives in different circumstances. The results indicate that the larger the vessel, the lower the discount rate, and the greater the price of Mixed Fuel Oil (a mixture of Very Low Sulphur Oil and Marine Gas Oil), the more attractive the scrubber option. Quantitatively, if the refining technology of low-sulphur fuel improves in the future and the price differential between Mixed Fuel Oil and Heavy Sulphur Fuel Oil decreases to $29 per ton for the 5000 TEU vessel or$27 per ton for the 10,000 TEU vessel, the fuel-switch alternative will be as competitive as the use of a scrubber in terms of the lifespan cost. Additionally, as the discount rate increases, the cost gap between the use of a scrubber and the other two alternatives gradually decreases

Benchmarking and Compliance in the UK Offshore Decommissioning Hazardous Waste Stream

The decommissioning sector of the United Kingdom offshore oil and gas industry is growing rapidly due to the number of ageing installations within United Kingdom waters. In line with current United Kingdom requirements, installations must be decontaminated from hazardous waste before any part can be reused or recycled. This hazardous waste must be handled, transported, and disposed of in a way that does not impact safety or the environment. This research project analyses the key issues associated with the handling of hazardous waste during the decommissioning of offshore installations with the United Kingdom Continental Shelf. A comprehensive literature review and analysis of decommissioning close-out reports was conducted to allow for the key issues to be identified. Expert judgements were sought and analysed using an analytical hierarchy process. This study emphases the need to improve the handling of hazardous materials during the decommissioning process. The clarity of legislative requirements, identification of hazardous materials and sharing of knowledge and experience are areas that require improvement to meet the increasingly stringent environmental and sustainability requirements

Total haemoglobin mass, but not haemoglobin concentration, is associated with preoperative cardiopulmonary exercise testing (CPET) derived oxygen consumption variables

BACKGROUND: Cardiopulmonary exercise testing (CPET) measures peak exertional oxygen consumption ( V˙O2peakV˙O2peak ) and that at the anaerobic threshold ( V˙O2V˙O2 at AT, i.e. the point at which anaerobic metabolism contributes substantially to overall metabolism). Lower values are associated with excess postoperative morbidity and mortality. A reduced haemoglobin concentration ([Hb]) results from a reduction in total haemoglobin mass (tHb-mass) or an increase in plasma volume. Thus, tHb-mass might be a more useful measure of oxygen-carrying capacity and might correlate better with CPET-derived fitness measures in preoperative patients than does circulating [Hb]. METHODS: Before major elective surgery, CPET was performed, and both tHb-mass (optimized carbon monoxide rebreathing method) and circulating [Hb] were determined. RESULTS: In 42 patients (83% male), [Hb] was unrelated to V˙O2V˙O2 at AT and V˙O2peakV˙O2peak (r=0.02, P=0.89 and r=0.04, P=0.80, respectively) and explained none of the variance in either measure. In contrast, tHb-mass was related to both (r=0.661, P<0.0001 and r=0.483, P=0.001 for V˙O2V˙O2 at AT and V˙O2peakV˙O2peak , respectively). The tHb-mass explained 44% of variance in V˙O2V˙O2 at AT (P<0.0001) and 23% in V˙O2peakV˙O2peak (P=0.001). CONCLUSIONS: In contrast to [Hb], tHb-mass is an important determinant of physical fitness before major elective surgery. Further studies should determine whether low tHb-mass is predictive of poor outcome and whether targeted increases in tHb-mass might thus improve outcome

Why do some women choose to freebirth in the UK? An interpretative phenomenological study

Background Freebirthing or unassisted birth is the active choice made by a woman to birth without a trained professional present, even where there is access to maternity provision. This is a radical childbirth choice, which has potential morbidity and mortality risks for mother and baby. While a number of studies have explored women’s freebirth experiences, there has been no research undertaken in the UK. The aim of this study was to explore and identify what influenced women’s decision to freebirth in a UK context. Methods An interpretive phenomenological approach was adopted. Advertisements were posted on freebirth websites, and ten women participated in the study by completing a narrative (n = 9) and/or taking part in an in-depth interview (n = 10). Data analysis was carried out using interpretative methods informed by Heidegger and Gadamer’s hermeneutic-phenomenological concepts. Results Three main themes emerged from the data. Contextualising herstory describes how the participants’ backgrounds (personal and/or childbirth related) influenced their decision making. Diverging paths of decision making provides more detailed insights into how and why women’s different backgrounds and experiences of childbirth and maternity care influenced their decision to freebirth. Converging path of decision making, outlines the commonalities in women’s narratives in terms of how they sought to validate their decision to freebirth, such as through self-directed research, enlisting the support of others and conceptualising risk. Conclusion The UK based midwifery philosophy of woman-centred care that tailors care to individual needs is not always carried out, leaving women to feel disillusioned, unsafe and opting out of any form of professionalised care for their births. Maternity services need to provide support for women who have experienced a previous traumatic birth. Midwives also need to help restore relationships with women, and co-create birth plans that enable women to be active agents in their birthing decisions even if they challenge normative practices. The fact that women choose to freebirth in order to create a calm, quiet birthing space that is free from clinical interruptions and that enhances the physiology of labour, should be a key consideration