168 research outputs found

    Experimental investigation of hydrodynamic slug mitigation potential of an intermittent absorber

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    The need to handle hydrodynamic slugs in a more efficient way becomes important as oil and gas activities shift deep offshore. This study describes the use of a vessel coupled to the pipeline-riser system upstream of the first stage separator for hydrodynamic slug attenuation. The experiments were carried out in a 2″ pipeline-riser system which comprises of a 40 m long horizontal pipe connected to a 11 m high vertical riser followed by a 3 m horizontal topside section. Air and water were used as experimental fluids. Bifurcation maps and slug attenuation index (SAI) have been used to quantify increase in oil production and the slug attenuation potential of this concept. The device was observed to reduce the pressure fluctuations characterising hydrodynamic slug flow up to 22%. The device also provides additional benefits of stabilising the flow at higher valve opening (choke setting) and lower pressure compared to traditional choking. This in practice translates to increase in oil production. Special case of hydrodynamic slugs which exhibit overchoking induced slugging (OIS) was also observed to be relatively attenuated by the introduction of the absorber

    Socio-Economic, Demand and Supply-Driven Determinants of Health Care Expenditures in Sub-Sahara Africa

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    This study examined the real determinants of health care expenditure in Sub-Sahara Africa. Considering the determining factors from socio-economic, demand and supply sides, data for the study were sourced from World Health Organization and World Development indicators published by World Bank. The study employed Westerlund Error-correction Based Panel Cointegration test to examine the relationship between the determining factors of health expenditure and the health expenditure itself. Findings from the study confirmed that there are long-term co-movements between the determining factors of health expenditure and health expenditure itself. Also, the study revealed that all variables from socio-economic, demand and supply sides have significant impacts on health expenditure in both short and long- run. In addition, most variables in the demand and supply sides have negative and significant impacts on health expenditure while all variables from socio-economic side have positive and significant impacts on health expenditure in both short and long-run in the selected Sub-Sahara African countries. Keywords: Health Expenditure, Socio-economic Side, Demand Side, Supply Side, Panel Unit Root test, Error Correction Based Panel Cointegration. DOI: 10.7176/RHSS/10-10-07 Publication date:May 31st 202

    Attenuating severe slug flow at large valve opening for increased oil production without feedback control signal

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    In the co-current flow of gas-liquid mixtures through pipeline-riser system, severe slugging is frequently encountered and manifests insignificant fluctuation of flow and pressure. This can pose serious threat to production facilities. The most common method for its mitigation is by choking which unfortunately could negatively affect production. The objective of this study therefore is to develop a technique that can help stabilise the system and maximise production simultaneously. In this paper, a new general method for multiphase flow system stability analysis was proposed based on a new passive attenuation method – the intermittent absorber. A series of experiments were carried out in a 4″ pipeline-riser system which is 55m long with horizontal pipe inclined at 2° connected to 10.5m high catenary riser followed by 3m horizontal topside section. Air and water were used as experimental fluids. Numerical studies were also conducted on a 4″ pipeline-riser system to proof the concept. The results showed that the intermittent absorber possess potential for flow at larger valve opening and lower pressure. For the case studied, up to 9% reduction in the riser base pressure was reported which practically implies increased oil production

    The niche of One Health approaches in Lassa fever surveillance and control

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    Lassa fever (LF), a zoonotic illness, represents a public health burden in West African countries where the Lassa virus (LASV) circulates among rodents. Human exposure hinges significantly on LASV ecology, which is in turn shaped by various parameters such as weather seasonality and even virus and rodent-host genetics. Furthermore, human behaviour, despite playing a key role in the zoonotic nature of the disease, critically affects either the spread or control of human-to-human transmission. Previous estimations on LF burden date from the 80s and it is unclear how the population expansion and the improvement on diagnostics and surveillance methods have affected such predictions. Although recent data have contributed to the awareness of epidemics, the real impact of LF in West African communities will only be possible with the intensification of interdisciplinary efforts in research and public health approaches. This review discusses the causes and consequences of LF from a One Health perspective, and how the application of this concept can improve the surveillance and control of this disease in West Africa

    Medicines management at home during the COVID-19 pandemic: a qualitative study exploring the UK patient/carer perspective

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    OBJECTIVES: To explore home medicine practices and safety for people shielding and/or over the age of 70 during the COVID-19 pandemic and to create guidance, from the patient/carer perspective, for enabling safe medicine practices for this population. METHODS: Semi-structured interviews were carried out with 50 UK participants who were shielding and/or over the age of 70 and who used medicines for a long-term condition, using telephone or video conferencing. Participants were recruited through personal/professional networks and through patient/carer organisations. Participants were asked about their experiences of managing medicines during the pandemic and how this differed from previous practices. Data were analysed using inductive thematic analysis. KEY FINDINGS: Patients' and their families' experiences of managing medicines safely during the pandemic varied greatly. Analysis suggests that this was based on the patient's own agency, the functioning of their medicines system pre-pandemic and their relationships with family, friends, community networks and pharmacy staff. Medicine safety issues reported included omitted doses and less-effective formulations being used. Participants also described experiencing high levels of anxiety related to obtaining medicines, monitoring medicines and feeling at risk of contracting COVID-19 while accessing healthcare services for medicine-related issues. Effects of the pandemic on medicines adherence were reported to be positive by some and negative by others. CONCLUSIONS: Pharmacy staff have a key role to play by establishing good relationships with patients and their families, working with prescribers to ensure medicines systems are as joined up as possible, and signposting to community networks that can help with medicines collection

    Six-year changes in body mass index and cardiorespiratory fitness of English schoolchildren from an affluent area

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    We compared values of body mass index (BMI) and cardiorespiratory fitness (20 m shuttle-run test) of n=157 boys and n=150 girls aged 10-11 measured in 2014 with measures from 2008 and 1998. Boys' fitness was lower (d=0.68) in 2014 than 2008, despite a small (d=0.37) decline in BMI. Girl's BMI changed trivially (d=0.08) but cardiorespiratory fitness was lower (d=0.47) in 2014 than 2008. This study suggests fitness is declining at 0.95% per year, which exceeds the 0.8% rate of decline we reported between 1998 and 2008 and is double the global average of 0.43%. Declines in fitness were independent of changes in BMI suggesting continued reductions in English children's habitual physical activity levels

    Exploring the barriers to, and importance of, participant diversity in early-phase clinical trials: an interview-based qualitative study of professionals and patient and public representatives

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    Objectives To explore the importance of, and barriers to achieving, diversity in early-phase clinical trials. Design Qualitative interviews analysed using thematic analysis. Setting and participants Five professionals (clinical researchers and methodologists) and three patient and public representatives (those with experience of early-phase clinical trials and/or those from ethnic minority backgrounds) were interviewed between June and August 2022. Participants were identified via their institutional web page, existing contacts or social media (eg, X, formerly known as Twitter). Results Professionals viewed that diversity is not currently considered in all early-phase clinical trials but felt that it should always be taken into account. Such trials are primarily undertaken at a small number of centres, thus limiting the populations they can access. Referrals from clinicians based in the community may increase diversity; however, those referred are often not from underserved groups. Referrals may be hindered by the extra resources required to approach and recruit underserved groups and participants often having to undertake ‘self-driven’ referrals. Patient and public representatives stated that diversity is important in research staff and that potential participants should be informed of the need for diversity. Those from underserved groups may require clarification regarding the potential harms of a treatment, even if these are unknown. Education may improve awareness and perception of early-phase clinical trials. We provide 14 recommendations to improve diversity in early-phase clinical trials. Conclusions Diversity should be considered in all early-phase trials. Consideration is required regarding the extent of diversity and how it is addressed. The increased resources needed to recruit those from underserved groups may warrant funders to increase the funds to support the recruitment of such participants. The potential harms and societal benefits of the research should be presented to potential participants in a balanced but accurate way to increase transparency

    Quantification of the Relative Age Effect in Three Indices of Physical Performance

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    The relative age effect (RAE) describes the relationship between an individual's birth month and their level of attainment in sports. There is a clustering of birth dates just after the cutoff used for selection in age-grouped sports, and it is hypothesized that such relatively older sportspeople may enjoy maturational and physical advantages over their younger peers. There is, however, little empirical evidence of any such advantage. This study investigated whether schoolchildren's physical performance differed according to which quarter of the school year they were born in. Mass, stature, body mass index, cardiorespiratory fitness, strength, and power were measured in 10 to 16 year olds (n = 8,550, 53% male). We expressed test performance as ageand sex-specific z-scores based on reference data with age rounded down to the nearest whole year and also as units normalized for body mass. We then compared these values between yearly birth quarters. There were no significant main effects for differences in anthropometric measures in either sex. Girls born in the first quarter of the school year were significantly stronger than those born at other times when handgrip was expressed as a zscore. As z-scores, all measures were significantly higher in boys born in either the first or second yearly quarters. Relative to body mass, cardiorespiratory fitness was higher in boys born in the first quarter and power was higher in those born in the second quarter. The RAE does not appear to significantly affect girls' performance test scores when they are expressed as z-score or relative to body mass. Boys born in the first and second quarters of the year had a significant physical advantage over their relatively younger peers. These findings have practical bearing if coaches use fitness tests for talent identification and team selection. Categorizing test performance based on rounded down values of whole-year age may disadvantage children born later in the selection year. These relatively younger children may be less to gain selection for teams or training programmes. © 2013 National Strength and Conditioning Association

    Physical activity and breast cancer survival

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    Physical activity improves quality of life after a breast cancer diagnosis, and a beneficial effect on survival would be particularly welcome. Four observational studies have now reported decreased total mortality among physically active women with breast cancer; the two largest have also reported decreased breast cancer specific mortality. The estrogen pathway and the insulin pathway are two potential mechanisms by which physical activity could affect breast cancer survival. Randomized trials are ongoing but trials of lifestyle factors are notoriously challenging to perform. Women with breast cancer have little to lose and may possibly gain from moderate exercise
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