7 research outputs found
Performance of Equilibrium Zeolite in Water-Based Mud at Elevated Temperature Conditions
This study looks at the performance of nano equilibrium zeolite treated drilling fluids at high temperatures conditions, and their potential as alternatives for oil-based muds (OBM). Mud samples for this study were prepared and aged with the equilibrium zeolite nanoparticles concentrations of 0.0 g, 0.5 g, 1.0 g and 1.5 g. Tests were performed to determine the rheological, filtration control properties, the pH and consequently the thermal stability of the study mud samples over a temperature range of 120 掳F to 360 掳F. One sample without the equilibrium zeolite served as a control for the study. From the results obtained, all the nano samples had their rheological properties not exhibiting much significant variation with temperature, thus they were more thermally stable, with the optimum nanoparticle concentration being 1.5 g. It was also hypothesized that the nano equilibrium zeolite behaved as thinners, since they were able to reduce the shear stresses, yield points, plastic viscosities and gel strengths of the mud samples as temperature was varied incrementally. It was therefore concluded that the optimum concentration of aged equilibrium zeolite has the potential to act as a thermal stability additive for Water Based Mud systems (WBMs)
Prognostic model to predict postoperative acute kidney injury in patients undergoing major gastrointestinal surgery based on a national prospective observational cohort study.
Background: Acute illness, existing co-morbidities and surgical stress response can all contribute to postoperative acute kidney injury (AKI) in patients undergoing major gastrointestinal surgery. The aim of this study was prospectively to develop a pragmatic prognostic model to stratify patients according to risk of developing AKI after major gastrointestinal surgery. Methods: This prospective multicentre cohort study included consecutive adults undergoing elective or emergency gastrointestinal resection, liver resection or stoma reversal in 2-week blocks over a continuous 3-month period. The primary outcome was the rate of AKI within 7 days of surgery. Bootstrap stability was used to select clinically plausible risk factors into the model. Internal model validation was carried out by bootstrap validation. Results: A total of 4544 patients were included across 173 centres in the UK and Ireland. The overall rate of AKI was 14路2 per cent (646 of 4544) and the 30-day mortality rate was 1路8 per cent (84 of 4544). Stage 1 AKI was significantly associated with 30-day mortality (unadjusted odds ratio 7路61, 95 per cent c.i. 4路49 to 12路90; P < 0路001), with increasing odds of death with each AKI stage. Six variables were selected for inclusion in the prognostic model: age, sex, ASA grade, preoperative estimated glomerular filtration rate, planned open surgery and preoperative use of either an angiotensin-converting enzyme inhibitor or an angiotensin receptor blocker. Internal validation demonstrated good model discrimination (c-statistic 0路65). Discussion: Following major gastrointestinal surgery, AKI occurred in one in seven patients. This preoperative prognostic model identified patients at high risk of postoperative AKI. Validation in an independent data set is required to ensure generalizability
Exploring Factors That Facilitate Acculturation Strategies and Academic Success of West African Immigrant Youth in Urban Schools
Immigrant students in U.S. educational system experience challenges learning to adapt and integrate into new educational environments. Little is known, however, about factors that facilitate acculturation strategies of immigrant youth from West Africa and how they affect their academic success and challenges faced. Considering the current political discourse over the influence of immigration in U.S. schools, 20 immigrant youth from Ghana and Nigeria were recruited and interviewed in the metropolitan area of New York City. Analyses of semi-structured interviews revealed that teacher, parent, and peer support; social and electronic media; and extracurricular activities emerged as the factors that helped acculturation strategies and academic success. Challenging factors were dealing with sociocultural differences; discrimination, stress, and social integration; and language differences. The article discusses the implications of these findings for teachers to understand acculturation strategies to help West African immigrant youth to adapt, acculturate, and integrate into new school environments
Adaptation of the Wound Healing Questionnaire universal-reporter outcome measure for use in global surgery trials (TALON-1 study): mixed-methods study and Rasch analysis
BackgroundThe Bluebelle Wound Healing Questionnaire (WHQ) is a universal-reporter outcome measure developed in the UK for remote detection of surgical-site infection after abdominal surgery. This study aimed to explore cross-cultural equivalence, acceptability, and content validity of the WHQ for use across low- and middle-income countries, and to make recommendations for its adaptation.MethodsThis was a mixed-methods study within a trial (SWAT) embedded in an international randomized trial, conducted according to best practice guidelines, and co-produced with community and patient partners (TALON-1). Structured interviews and focus groups were used to gather data regarding cross-cultural, cross-contextual equivalence of the individual items and scale, and conduct a translatability assessment. Translation was completed into five languages in accordance with Mapi recommendations. Next, data from a prospective cohort (SWAT) were interpreted using Rasch analysis to explore scaling and measurement properties of the WHQ. Finally, qualitative and quantitative data were triangulated using a modified, exploratory, instrumental design model.ResultsIn the qualitative phase, 10 structured interviews and six focus groups took place with a total of 47 investigators across six countries. Themes related to comprehension, response mapping, retrieval, and judgement were identified with rich cross-cultural insights. In the quantitative phase, an exploratory Rasch model was fitted to data from 537 patients (369 excluding extremes). Owing to the number of extreme (floor) values, the overall level of power was low. The single WHQ scale satisfied tests of unidimensionality, indicating validity of the ordinal total WHQ score. There was significant overall model misfit of five items (5, 9, 14, 15, 16) and local dependency in 11 item pairs. The person separation index was estimated as 0.48 suggesting weak discrimination between classes, whereas Cronbach's 伪 was high at 0.86. Triangulation of qualitative data with the Rasch analysis supported recommendations for cross-cultural adaptation of the WHQ items 1 (redness), 3 (clear fluid), 7 (deep wound opening), 10 (pain), 11 (fever), 15 (antibiotics), 16 (debridement), 18 (drainage), and 19 (reoperation). Changes to three item response categories (1, not at all; 2, a little; 3, a lot) were adopted for symptom items 1 to 10, and two categories (0, no; 1, yes) for item 11 (fever).ConclusionThis study made recommendations for cross-cultural adaptation of the WHQ for use in global surgical research and practice, using co-produced mixed-methods data from three continents. Translations are now available for implementation into remote wound assessment pathways