Operational Research: methods and applications

This is the final version. Available on open access from Taylor & Francis via the DOI in this recordThroughout its history, Operational Research has evolved to include methods, models and algorithms that have been applied to a wide range of contexts. This encyclopedic article consists of two main sections: methods and applications. The first summarises the up-to-date knowledge and provides an overview of the state-of-the-art methods and key developments in the various subdomains of the field. The second offers a wide-ranging list of areas where Operational Research has been applied. The article is meant to be read in a nonlinear fashion and used as a point of reference by a diverse pool of readers: academics, researchers, students, and practitioners. The entries within the methods and applications sections are presented in alphabetical order. The authors dedicate this paper to the 2023 Turkey/Syria earthquake victims. We sincerely hope that advances in OR will play a role towards minimising the pain and suffering caused by this and future catastrophes

Antioxidant and cytotoxic activities of<i style=""> Caesalpinia pulcherrima </i>wood

198-200Antioxidant and cytotoxic activities of the methanolic and aqueous extracts of Caesalpinia pulcherrima wood were studied in in vitro models. Both extracts exhibited strong antioxidant activity, as evidenced by the low IC50 values in both 1,1-diphenyl-2-picryl hydrazyl (DPPH), nitric oxide and superoxide scavenging methods; the values were found to be less or comparable to those of gallic acid, the standard used. To determine the cytotoxic activity, extracts were tested for toxic effects to brine shrimp larvae. In this assay, the methanolic extract had little effect, but aqueous extract was relatively toxic. The antioxidant and cytotoxic activities may be attributed to the total phenolic content in the wood

Postgraduate career intentions of medical students and recent graduates in Malawi: a qualitative interview study.

BACKGROUND: In 2004, the Malawian Ministry of Health declared a human resource crisis and launched a six year Emergency Human Resources Programme. This included salary supplements for key health workers and a tripling of doctors in training. By 2010, the number of medical graduates had doubled and significantly more doctors were working in rural district hospitals. Yet there has been little research into the views of this next generation of doctors in Malawi, who are crucial to the continuing success of the programme. The aim of this study was to explore the factors influencing the career plans of medical students and recent graduates with regard to four policy-relevant aspects: emigration outside Malawi; working at district level; private sector employment and postgraduate specialisation. METHODS: Twelve semi-structured interviews were conducted with fourth year medical students and first year graduates, recruited through purposive and snowball sampling. Key informant interviews were also carried out with medical school faculty. Recordings were transcribed and analysed using a framework approach. RESULTS: Opportunities for postgraduate training emerged as the most important factor in participants' career choices, with specialisation seen as vital to career progression. All participants intended to work in Malawi in the long term, after a period of time outside the country. For nearly all participants, this was in the pursuit of postgraduate study rather than higher salaries. In general, medical students and young doctors were enthusiastic about working at district level, although this is curtailed by their desire for specialist training and frustration with resource shortages. There is currently little intention to move into the private sector. CONCLUSIONS: Future resourcing of postgraduate training opportunities is crucial to preventing emigration as graduate numbers increase. The lesser importance put on salary by younger doctors may be an indicator of the success of salary supplements. In order to retain doctors at district levels for longer, consideration should be given to the introduction of general practice/family medicine as a specialty. Returning specialists should be encouraged to engage with younger colleagues as role models and mentors

Phytochemical profile, antioxidant, cytotoxic and anti-inflammatory activities of stem bark extract and fractions of Ailanthus excelsa Roxb.: In vitro, in vivo and in silico approaches

This study aimed to assess the phytochemical composition, in vitro antioxidant, cytotoxicity, and in vivo anti-inflammatory activities of the methanolic extract of Ailanthus excelsa (Simaroubaceae) stem bark and its fractions. Quantitative phytochemical analysis revealed that methanolic extract and all fractions contained a high level of flavonoids (20.40–22.91 mg/g QE), phenolics (1.72–7.41 mg/g GAE), saponins (33.28–51.87 mg/g DE), and alkaloids (0.21–0.33 mg/g AE). The antioxidant potential was evaluated in vitro using a range of assays, i.e., DPPH•, ABTS radical scavenging ability, and total antioxidant capacity. The chloroform and ethyl acetate fractions showed stronger antioxidant activity than the methanol extract. In vitro cytotoxic activity was investigated in three human tumor cell lines (A-549, MCF7 and HepG2) using the SRB assay. In addition, the in vivo anti-inflammatory effect was assessed by carrageenan-induced paw edema in rats. The chloroform fraction showed a more pronounced effect by effectively controlling the growth with the lowest GI50 and TGI concentrations. The human lung cancer cell line (A-549) was found to be more sensitive to the chloroform fraction. Furthermore, the chloroform fraction exhibited significant anti-inflammatory activity at a dose of 200 mg/kg in the latter phase of inflammation. Besides, methanol extract and ethyl acetate fraction revealed a significant cytotoxic and anti-inflammatory effects. The chloroform fraction of stem bark showed a strong anti-inflammatory effect in experimental animals and significant COX-2 inhibitory potential in the in vitro experiments. GC-MS analysis of chloroform fraction identified the phytochemicals like caftaric acid, 3,4-dihydroxy phenylacetic acid, arachidonic acid, cinnamic acid, 3-hydroxyphenylvaleric acid, caffeic acid, hexadeconoic acid, and oleanolic acid. The in-silico results suggest that identified compounds have better affinity towards the selected targets, viz. the BAX protein (PDB ID: 1F16), p53-binding protein Mdm-2 (PDB ID: 1YCR), and topoisomerase II (PDB ID: 1QZR). Amongst all, caftaric acid exhibited the best binding affinity for all three targets. Thus, it can be concluded that caftaric acid in combination with other phenolic compounds, might be responsible for the studied activity. Additional in vivo and in vitro studies are required to establish their exact molecular mechanisms and consider them as lead molecules in developing of valuable drugs for treating oxidative stress-induced disorders, cancers, and inflammations