34 research outputs found
A Single-Lumen Central Venous Catheter for Continuous and Direct Intra-abdominal Pressure Measurement
Background: Abdominal compartment syndrome (ACS) is associated with high morbidity and mortality rates. Therefore, the need for a good diagnostic tool to predict intra-abdominal hypertension (IAH) and progression to ACS is paramount. Bladder pressure (BP) has been used for several years for intra-abdominal pressure (IAP) measurement but has the disadvantage that it is not a continuous measurement. In this study, a single-lumen central venous catheter (CVC) is placed through the abdominal wall into the abdominal cavity to continuously and directly monitor the intra-abdominal pressure (CDIAP). The aim of this study was to evaluate the use of CDIAP to measure BP as a representative of the true IAP. Methods: Both BP and CDIAP were prospectively recorded on a variety of surgical patients admitted to the intensive care unit (ICU) from March 2003 up to December 2004. At the end of the surgical procedure, the CVC was placed through the abdominal wall and connected to a pressure transducer. In addition, the BP was measured through the urine drainage port after clamping the catheter and filling the bladder with 50 ml of 0.9% saline. At least three paired measurements (BP and CDIAP) were performed for at least one day on the ICU in a standardized manner at preset time intervals on each patient. The paired measurements were compared using the Bland-Altman (B-A) method. Data are presented as mean ± standard deviation. Results: Over a period of 22 months (March 2003 until December 2004), 125 paired measurements of both BP and CDIAP were recorded on 25 patients. The mean age was 72.4 ± 6.6 years. Eighteen patients underwent central vascular surgery, and seven patients with peritonitis received laparotomy. The mean CDIAP was 11.4 ± 4.8 (range 2-30) mmHg, and the BP was 12.9 ± 5.3 (range 3-37) mmHg. The mean difference between CDIAP and BP was 1.6 ± 2.7 mmHg. There was an acceptable level of agreement (intraclass correlation 0.82) between IAP measured by BP and IAP measured via CDIAP. Conclusion: Continuous direct intra-abdominal pressure measurement proved that the BP measurement approach of Kron is representative of the IAP. CDIAP measurement is accurate and makes it easier for the nursing staff to be informed of the IAP
Helium identification with LHCb
The identification of helium nuclei at LHCb is achieved using a method based on measurements of ionisation losses in the silicon sensors and timing measurements in the Outer Tracker drift tubes. The background from photon conversions is reduced using the RICH detectors and an isolation requirement. The method is developed using pp collision data at √(s) = 13 TeV recorded by the LHCb experiment in the years 2016 to 2018, corresponding to an integrated luminosity of 5.5 fb-1. A total of around 105 helium and antihelium candidates are identified with negligible background contamination. The helium identification efficiency is estimated to be approximately 50% with a corresponding background rejection rate of up to O(10^12). These results demonstrate the feasibility of a rich programme of measurements of QCD and astrophysics interest involving light nuclei
Curvature-bias corrections using a pseudomass method
Momentum measurements for very high momentum charged particles, such as muons from electroweak vector boson decays, are particularly susceptible to charge-dependent curvature biases that arise from misalignments of tracking detectors. Low momentum charged particles used in alignment procedures have limited sensitivity to coherent displacements of such detectors, and therefore are unable to fully constrain these misalignments to the precision necessary for studies of electroweak physics. Additional approaches are therefore required to understand and correct for these effects. In this paper the curvature biases present at the LHCb detector are studied using the pseudomass method in proton-proton collision data recorded at centre of mass energy √(s)=13 TeV during 2016, 2017 and 2018. The biases are determined using Z→μ + μ - decays in intervals defined by the data-taking period, magnet polarity and muon direction. Correcting for these biases, which are typically at the 10-4 GeV-1 level, improves the Z→μ + μ - mass resolution by roughly 18% and eliminates several pathological trends in the kinematic-dependence of the mean dimuon invariant mass
Momentum scale calibration of the LHCb spectrometer
For accurate determination of particle masses accurate knowledge of the momentum scale of the detectors is crucial. The procedure used to calibrate the momentum scale of the LHCb spectrometer is described and illustrated using the performance obtained with an integrated luminosity of 1.6 fb-1 collected during 2016 in pp running. The procedure uses large samples of J/ψ → μ + μ - and B+ → J/ψ K + decays and leads to a relative accuracy of 3 × 10-4 on the momentum scale
Improving health outcomes for girls: reflections on the impact on body issues of a girl's only health and physical education intervention
Background: The issues surrounding girls' lack of participation in physical activity are many and varied, but\ud
generally relate to the broader social context of adolescent health in which the social relations of gender play a significant part in a lack of engagement with sports; with a lack of physical skills and confidence for\ud
equitable participation; friendship considerations; body image issues and a concern about bullying and\ud
harassment.\ud
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Objectives: This paper reports on data collected as part of a larger project researching the impact of a non-traditional physical education and health intervention designed to build girls connectedness to each other,\ud
their school and their community by engaging them in a girls' only negotiated physical activity program that\ud
was supported by a targeted health education curricula.\ud
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Underlying values and principles: Grade 8 girls in the State of Victoria, Australia have the lowest school\ud
connectedness data than any other cohort. Using youth participation principles and underpinned by strong\ud
educational guidelines an integrated health and physical education program was developed by a high school\ud
in Australia in an attempt to improve connectedness. It facilitated the exploration of a number of different\ud
lifestyle physical activities such as bellying dance, self-defense and yoga, to engage the girls with alternative\ud
physical activities that were potentially available in their community as well as discussion and activities on\ud
sexuality, body image and mental health.\ud
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Knowledge base/ Evidence base: Whilst evaluation of girls' only physical activity programs are not new,\ud
research into the impact of an integrated school-based health and physical education curricula are and have\ud
implications for future school based approaches.\ud
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Context of intervention/project/work: The project initially focused on adolescent girls at a small 7-12\ud
Secondary College in an isolated community approximately 200 kilometres from the Capital city of Victoria. A\ud
grant was awarded to a consortium of local/regional agencies to implement and extend the program over\ud
three years. Overwhelmingly the program was conducted by regional and local agencies in conjunction with\ud
the local secondary school. It is a partnerships model built on the notion of increasing participation and\ud
access for young women whilst building a sustainable program run in partnership with the school and local\ud
agencies and services. In 2009 the program was also run in a metropolitan secondary school that had a\ud
similar socia-economic background. This paper draws on data from both schools.\ud
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Methods: This paper reports on qualitative date collected on young women's perceptions of the program, its\ud
contribution to their health and wellbeing and the impact of the program on understandings of health related\ud
issues of relevance to young women. The data is drawn from focus group data collected from two high\ud
schools in the state of Victoria, Australia in 2007, 2008 and 2009. Sixty five girls' in grade 7, 8, 9 and 10\ud
participated in the pre and post program interviews.\ud
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Results and Conclusions: We argue that whilst the data indicates that a girls only program can have a\ud
pOSitive impact on aspect of connectedness such as relationships with their peers, reducing bullying\ud
behaviour, the data raises some important questions around the adequacy of school-based health education,\ud
and the sustainability of approaches designed to be delivered by outside agencies rather than classroom\ud
teachers. We argue that whilst single sex health and physical education programs may be necessary for girls\ud
to participate and engage fully, the current approach has little impact on traditional notions of gender and\ud
body issues.\ud
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Disclosure of Interest: Centre for Educational Futures and Innovation, Grant Research Support. Victorian Health Promotion Foundation, Grant Research Support