107 research outputs found
Soft OR and practice : the contribution of the founders of Operation Research
This paper explores the work of some 43 founders of operations research. In particular, it considers the links between soft operations research (OR) and these founders. Several of the founders were direct influencers of the soft OR proponents, whereas others related to the context, process, and content of soft OR. Coupled with the deductive and inductive reasoning approaches of soft OR, it is argued that soft OR is a legitimate branch of OR. The paper also focuses on the embeddedness of the founders, and the soft OR proponents, in practice and argues that, for academics, engagement with practice has been and will continue to be an important driver for the health and development of operations research
Establishing a bioconversion process for the production of succinic acid using industrial feedstocks.
Masters Degree. University of KwaZulu-Natal, Durban.One of the leading challenges of the current global situation is the decline of non-renewable, fossil fuels. Due to this rapid depletion, there is a shift towards replacing petrochemical products with equivalent, ideally superior bio-based substitutes. The bio-chemical of interest that was studied in this work is bio-succinic acid which is considered a platform chemical. Bio-based procedures have the attractive advantage of potentially obtaining a high-value product from an underutilised product/waste stream. In this dissertation, the industry that was focused on was the sugar sector, this vital industry is under pressure it is therefore crucial that alternative revenue avenues are identified.
A literature study highlighted the importance of succinic acid, detailed both the upstream and downstream literature methods and addressed the impact that biochemical processes could have within South Africa. Small scale flask studies were conducted using succinate-producing microorganisms, on synthetic C5 and C6 sugar medias, namely xylose and glucose. The results from these studies showed that L. paracasei and C. glutamicum were the top performing strains on the C6 sugar (glucose) media and as a result these strains were then grown on C6 industrial material, namely sugarcane juice and molasses. These flask studies concluded that C. glutamicum grown on molasses was the superior combination, with a succinic acid concentration of 18.81 ± 0.75 g.L-1 and a productivity of 0.67 ± 0.07 g.L-1.hr-1 being achieved. The process was then successfully scaled up to 30L reactors where a succinic acid concentration of 28.89 ± 3.57 g.L-1 was reached, which was higher than the âidealâ glucose reactor run. Downstream processing of the harvested broth was conducted using the precipitation method. Process development was performed, and the final method resulted in a final succinic acid recovery of 54.47 ± 14.02 % and 58.20 ± 2.24 % for the glucose and molasses-based medias respectively. In conclusion, molasses has the potential as an alternative carbon source in the production of succinic acid. The biochemicals sector is still a novel concept within South Africa, and as this platform gains more traction such studies show the âvalueâ of industryâs waste/by-product streams, especially for the sugar industry
The relationship of milk expression pattern and lactation outcomes after very premature birth: A cohort study
Introduction: Mothers of very premature infants often have difficulties expressing breastmilk, which can cause distress and potential negative impact on infant health. Clinical recommendations on breastmilk expression are extrapolated from term infantsâ breastfeeding patterns. This studyâs objective was to analyse the association of expressing pattern with lactation outcomes after very premature birth. Methods: 132 participants were recruited after birth between 23+0 and 31+6 weeksâ gestation. Participants recorded the milk expressed in several 24-hour periods in the three weeks after birth. Results: Expressing frequency was positively associated with 24-hour milk yield, with an adjusted 30.5g increase per expressing session on day four (95% CI 15.7 to 45.3) and 94.4g on day 21 (95% CI 62.7 to 126.2). Expressing â„8 times per day was associated with higher adjusted milk yield than expressing <6 times (on day four, 146.8g, 95% CI 47.4 to 246.1), but not in comparison to expressing 6â7 times (on day four, 82.1g, 95% CI â25.9 to 190.1). Participants with six months or more prior breastmilk feeding experience had a higher adjusted milk yield than others (on day four, 204.3g, 95% CI 125.2 to 283.3). Night-time (2300â0700 hours) expressing sessions were not associated with increased milk yield after adjustment for time since the prior session. On average, participants who had a longest gap between expressions of less than six hours achieved the UK target of 750g breastmilk, whereas those with a longer gap did not. Conclusion: Expressing frequency was an important determinant of milk yield. Clinical recommendations to express â„8 times per day were supported but for some, 6â7 times was sufficient. This was particularly likely for those with six months or more of prior breastmilk feeding experience. A need to express during the night-time hours appeared to be related to minimising the gap between expressions rather than an inherent value of night-time expression
Cultivating a Resilient Response to Stress through Mindfulness and Cognitive Re-appraisal: A Pilot Randomised Control Trial
The capacity for human service professionals to replenish resilience is important to their health and psychological wellbeing. The current study evaluated a brief Mindful Awareness and Resilience Skills Training (MARST) program designed to enhance mindfulness and positive re-appraisal as psychological mechanisms for increasing resilience, decreasing psychological distress and perceived stress. This program was informed by the Mindful-Cognitive Model of Cultivating Resilience. A sample of 46 human service professionals were randomly allocated to a MARST group or control group. Short term and follow-up training effects were examined using MANOVA. At post-training, the MARST group reported significantly higher levels of resilience, mindfulness and positive re-appraisal compared to the control group. At one-month follow-up, the MARST group reported significantly higher levels of resilience, mindfulness, and positive re-appraisal, and significantly lower levels of perceived stress and psychological distress relative to the control group. The findings provide preliminary support for the efficacy of the MARST program to increase resilience and decrease levels of psychological distress and perceived stress among human services professionals
Repurposing literacy: the uses of Richard Hoggart for creative education
After 50 years, what are the implications of Uses of Literacy for educational modernisation, in the light of subsequent changes from 'read only' literacy to 'read-write' uses of multimedia? This chapter argues that a broad extension of popular literacy via consumer-created digital content offers not only emancipationist potential in line with Hoggart's own project, but also economic benefits via the dynamics of creative innovation. Multimedia 'popular entertainments' pose a challenge to formal education, but not in the way that Hoggart feared. Instead of producing 'tamed helots,' commercial culture may be outpacing formal schooling in promoting creative digital literacy via entrepreneurial and distributed learning. It may indeed be that those in need of a creative make-over are not teenagers but teachers
Re-imagining the data collection and analysis research process by proposing a rapid qualitative data collection and analytic roadmap applied to the dynamic context of precision medicine
Our implementation science study focuses on implementing a new way of practice and offers methodological specificity about how to rapidly investigate an individually tailored precision medicine intervention. A qualitative study advancing a new methodology for speedily identifying barriers and enablers to implementation in the context of childhood cancer. Data were collected through rapid ethnography, coded using the Consolidated Framework for Implementation Research, and analysed by Sentiment Analysis. Thirty-eight data collection events occurred during 14 multidisciplinary tumour board meetings, 14 curation meetings, and 10 informal conversations. Sentiment Analysis distilled Consolidated Framework for Implementation Research codes to reveal key barriers and enablers to implementation. A traffic light labelling system has been used to present levels of positivity and negativity (green for strong enablers and red for strong barriers), highlighting levels of concern regarding implementation. Within the intervention design characteristics, âAdaptabilityâ was the strongest enabler and âDesign quality and safetyâ the strongest barrier. Among the contextual factors: âNetworks and communicationâ were the strongest enabler, and âAvailable resourcesâ were the strongest barrier. Overall, there was a higher percentage of negative sentiment towards intervention design characteristics and contextual factors than positive sentiment, while more concerns were raised about intervention design factors than contextual factors. This study offers a rapid qualitative data collection and analytic methodological roadmap for establishing barriers and enablers to a paediatric precision medicine intervention
The Association of Persistent Symptoms of Depression and Anxiety with Recurrent Acute Coronary Syndrome Events: A Prospective Observational Study
The purpose of this study was to examine the role of persistent symptoms of depression and anxiety in a second acute coronary syndrome (ACS) event. Data presented in this study were from an RCT study. A follow-up for 24 months after baseline to detect a second ACS event among 1162 patients from five hospitals. Hierarchal Cox regression analyses were used. The results showed that persistent depression only (HR 2.27; 95% CI: 1.35â3.81; p = 0.002), and comorbid persistent depression and anxiety (HR 2.03; 95% CI: 1.03â3.98; p = 0.040) were the significant predictors of a second ACS event. Secondary education level compared to primary educational level (HR 0.63; 95% CI: 0.43â0.93; p = 0.020) and college or more education level compared to primary educational level (HR 0.47; 95% CI: 0.27â0.84; p = 0.011) were the only demographic variables that were significant predictors of a second event. The study reveals that attention must be paid by healthcare providers to assess and manage persistent depression; particularly when it is co-morbid with anxiety
A Genetic Animal Model of Alcoholism for Screening Medications to Treat Addiction
The purpose of this review is to present up-to-date pharmacological, genetic, and behavioral findings from the alcohol-preferring P rat and summarize similar past work. Behaviorally, the focus will be on how the P rat meets criteria put forth for a valid animal model of alcoholism with a highlight on its use as an animal model of polysubstance abuse, including alcohol, nicotine, and psychostimulants. Pharmacologically and genetically, the focus will be on the neurotransmitter and neuropeptide systems that have received the most attention: cholinergic, dopaminergic, GABAergic, glutamatergic, serotonergic, noradrenergic, corticotrophin releasing hormone, opioid, and neuropeptide Y. Herein, we sought to place the P rat's behavioral and neurochemical phenotypes, and to some extent its genotype, in the context of the clinical literature. After reviewing the findings thus far, this chapter discusses future directions for expanding the use of this genetic animal model of alcoholism to identify molecular targets for treating drug addiction in general
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Effect of Hydrocortisone on Mortality and Organ Support in Patients With Severe COVID-19: The REMAP-CAP COVID-19 Corticosteroid Domain Randomized Clinical Trial.
Importance: Evidence regarding corticosteroid use for severe coronavirus disease 2019 (COVID-19) is limited. Objective: To determine whether hydrocortisone improves outcome for patients with severe COVID-19. Design, Setting, and Participants: An ongoing adaptive platform trial testing multiple interventions within multiple therapeutic domains, for example, antiviral agents, corticosteroids, or immunoglobulin. Between March 9 and June 17, 2020, 614 adult patients with suspected or confirmed COVID-19 were enrolled and randomized within at least 1 domain following admission to an intensive care unit (ICU) for respiratory or cardiovascular organ support at 121 sites in 8 countries. Of these, 403 were randomized to open-label interventions within the corticosteroid domain. The domain was halted after results from another trial were released. Follow-up ended August 12, 2020. Interventions: The corticosteroid domain randomized participants to a fixed 7-day course of intravenous hydrocortisone (50 mg or 100 mg every 6 hours) (nâ=â143), a shock-dependent course (50 mg every 6 hours when shock was clinically evident) (nâ=â152), or no hydrocortisone (nâ=â108). Main Outcomes and Measures: The primary end point was organ support-free days (days alive and free of ICU-based respiratory or cardiovascular support) within 21 days, where patients who died were assigned -1 day. The primary analysis was a bayesian cumulative logistic model that included all patients enrolled with severe COVID-19, adjusting for age, sex, site, region, time, assignment to interventions within other domains, and domain and intervention eligibility. Superiority was defined as the posterior probability of an odds ratio greater than 1 (threshold for trial conclusion of superiority >99%). Results: After excluding 19 participants who withdrew consent, there were 384 patients (mean age, 60 years; 29% female) randomized to the fixed-dose (nâ=â137), shock-dependent (nâ=â146), and no (nâ=â101) hydrocortisone groups; 379 (99%) completed the study and were included in the analysis. The mean age for the 3 groups ranged between 59.5 and 60.4 years; most patients were male (range, 70.6%-71.5%); mean body mass index ranged between 29.7 and 30.9; and patients receiving mechanical ventilation ranged between 50.0% and 63.5%. For the fixed-dose, shock-dependent, and no hydrocortisone groups, respectively, the median organ support-free days were 0 (IQR, -1 to 15), 0 (IQR, -1 to 13), and 0 (-1 to 11) days (composed of 30%, 26%, and 33% mortality rates and 11.5, 9.5, and 6 median organ support-free days among survivors). The median adjusted odds ratio and bayesian probability of superiority were 1.43 (95% credible interval, 0.91-2.27) and 93% for fixed-dose hydrocortisone, respectively, and were 1.22 (95% credible interval, 0.76-1.94) and 80% for shock-dependent hydrocortisone compared with no hydrocortisone. Serious adverse events were reported in 4 (3%), 5 (3%), and 1 (1%) patients in the fixed-dose, shock-dependent, and no hydrocortisone groups, respectively. Conclusions and Relevance: Among patients with severe COVID-19, treatment with a 7-day fixed-dose course of hydrocortisone or shock-dependent dosing of hydrocortisone, compared with no hydrocortisone, resulted in 93% and 80% probabilities of superiority with regard to the odds of improvement in organ support-free days within 21 days. However, the trial was stopped early and no treatment strategy met prespecified criteria for statistical superiority, precluding definitive conclusions. Trial Registration: ClinicalTrials.gov Identifier: NCT02735707
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