15 research outputs found

    Nomogram for predicting the probability of the positive outcome of prostate biopsies among Ghanaian men

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    Introduction and objectives: Several existing models have been developed to predict positive prostate biopsy among men undergoing evaluation for prostate cancer (PCa). However, most of these models have come from industrialized countries. We therefore, developed a prostate disease nomogram model to provide a basis for predicting a prostate biopsy outcome by correlating clinical indicators and diagnostic parameters among Ghanaian men.Subjects and methods: The study was a hospital-based cross-sectional prospective one which was under- taken at the Department of Surgery (Urology Unit) Komfo Anokye Teaching Hospital (KATH) from December, 2014 to March, 2016. In all a total of 241 patients suspected of having a prostate disorder due based on an abnormal digital rectal examination (DRE) findings and, or elevated prostate specific antigen (PSA) level underwent Trans-Rectal Ultrasonography (TRUS) guided biopsy of the prostate. Stepwise logistic regression was used to determine the independent predictors of a positive initial biopsy. Age, prostatespecific antigen (PSA), digital rectal examination (DRE) status, prostate specific antigen density (PSAD), history of alcohol consumption and history of smoking findings were included in the analysis. Two nomogram models were developed that were based on these independent predictors to estimate the probability of a positive initial prostate biopsy. Receiver-operating characteristic curves (ROC) were used to assess the accuracy of using the nomograms and PSA and PSAD levels for predicting positive a prostate biopsy outcome. Results: Prostate cancer was diagnosed in 63 out of 241 patients (26.1%). Benign prostatic hyperplasia was diagnosed in 172 (71.4%) of patients and the remaining 6 patients (2.48%) had chronic inflammation. Significantly elevated levels of PSA and PSAD were observed among patients with PCa compared to patients without PCa (p < 0.05). Furthermore, it was observed that age, DRE, PSA, PSAD, history of smoking, and history of alcohol consumption were significantly independent predictors (p < 0.05) of prostate cancer. The area under the receiver operating characteristic curve (AUC) of nomogram I and II were 87.3 and 84.8 respectively which were greater than that of total PSA (AUC = 75.8) and PSAD (AUC = 77.8) alone for predicting a positive initial prostate biopsy. Conclusion: We conclude that, nomograms offer a better and accurate assessment for predicting a positive outcome of prostate biopsies than the use of traditional tools of PSA, DRE and PSAD alone

    Resilient Strategies and Sustainability in Agri-Food Supply Chains in the Face of High-Risk Events

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    [EN] Agri-food supply chains (AFSCs) are very vulnerable to high risks such as pandemics, causing economic and social impacts mainly on the most vulnerable population. Thus, it is a priority to implement resilient strategies that enable AFSCs to resist, respond and adapt to new market challenges. At the same time, implementing resilient strategies impact on the social, economic and environmental dimensions of sustainability. The objective of this paper is twofold: analyze resilient strategies on AFSCs in the literature and identify how these resilient strategies applied in the face of high risks affect the achievement of sustainability dimensions. The analysis of the articles is carried out in three points: consequences faced by agri-food supply chains due to high risks, strategies applicable in AFSCs, and relationship between resilient strategies and the achievement of sustainability dimensions.Authors of this publication acknowledge the contribution of the Project 691249, RUC-APS "Enhancing and implementing Knowledge based ICT solutions within high Risk and Uncertain Conditions for Agriculture Production Systems" (www.ruc-aps.eu), funded by the European Union under their funding scheme H2020-MSCA-RISE-2015.Zavala-Alcívar, A.; Verdecho Sáez, MJ.; Alfaro Saiz, JJ. (2020). Resilient Strategies and Sustainability in Agri-Food Supply Chains in the Face of High-Risk Events. IFIP Advances in Information and Communication Technology. 598:560-570. https://doi.org/10.1007/978-3-030-62412-5_46S560570598Gray, R.: Agriculture, transportation, and the COVID-19 crisis. Can. J. Agric. 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    Higher dose corticosteroids in patients admitted to hospital with COVID-19 who are hypoxic but not requiring ventilatory support (RECOVERY): a randomised, controlled, open-label, platform trial

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    BACKGROUND: Low-dose corticosteroids have been shown to reduce mortality for patients with COVID-19 requiring oxygen or ventilatory support (non-invasive mechanical ventilation, invasive mechanical ventilation, or extracorporeal membrane oxygenation). We evaluated the use of a higher dose of corticosteroids in this patient group. METHODS: This randomised, controlled, open-label platform trial (Randomised Evaluation of COVID-19 Therapy [RECOVERY]) is assessing multiple possible treatments in patients hospitalised for COVID-19. Eligible and consenting adult patients with clinical evidence of hypoxia (ie, receiving oxygen or with oxygen saturation <92% on room air) were randomly allocated (1:1) to either usual care with higher dose corticosteroids (dexamethasone 20 mg once daily for 5 days followed by 10 mg dexamethasone once daily for 5 days or until discharge if sooner) or usual standard of care alone (which included dexamethasone 6 mg once daily for 10 days or until discharge if sooner). The primary outcome was 28-day mortality among all randomised participants. On May 11, 2022, the independent data monitoring committee recommended stopping recruitment of patients receiving no oxygen or simple oxygen only due to safety concerns. We report the results for these participants only. Recruitment of patients receiving ventilatory support is ongoing. The RECOVERY trial is registered with ISRCTN (50189673) and ClinicalTrials.gov (NCT04381936). FINDINGS: Between May 25, 2021, and May 13, 2022, 1272 patients with COVID-19 and hypoxia receiving no oxygen (eight [1%]) or simple oxygen only (1264 [99%]) were randomly allocated to receive usual care plus higher dose corticosteroids (659 patients) versus usual care alone (613 patients, of whom 87% received low-dose corticosteroids during the follow-up period). Of those randomly assigned, 745 (59%) were in Asia, 512 (40%) in the UK, and 15 (1%) in Africa. 248 (19%) had diabetes and 769 (60%) were male. Overall, 123 (19%) of 659 patients allocated to higher dose corticosteroids versus 75 (12%) of 613 patients allocated to usual care died within 28 days (rate ratio 1·59 [95% CI 1·20–2·10]; p=0·0012). There was also an excess of pneumonia reported to be due to non-COVID infection (64 cases [10%] vs 37 cases [6%]; absolute difference 3·7% [95% CI 0·7–6·6]) and an increase in hyperglycaemia requiring increased insulin dose (142 [22%] vs 87 [14%]; absolute difference 7·4% [95% CI 3·2–11·5]). INTERPRETATION: In patients hospitalised for COVID-19 with clinical hypoxia who required either no oxygen or simple oxygen only, higher dose corticosteroids significantly increased the risk of death compared with usual care, which included low-dose corticosteroids. The RECOVERY trial continues to assess the effects of higher dose corticosteroids in patients hospitalised with COVID-19 who require non-invasive ventilation, invasive mechanical ventilation, or extracorporeal membrane oxygenation. FUNDING: UK Research and Innovation (Medical Research Council), National Institute of Health and Care Research, and Wellcome Trust

    A systems thinking approach to understand the drivers of change in backyard poultry farming system

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    Abstract CONTEXT Drivers of change in farming systems are not static, they evolve. Yet, there is an underlying assumption in the literature that drivers of change are static. OBJECTIVE This paper seeks to understand how drivers of change in Ghana's backyard poultry farming system evolve within a calendar year and examine how different production strategies contribute to the incomes of farm households. METHODS A system dynamics model, comprising production, financial, consumption, and epidemiological modules, was developed, validated, and simulated for a 52-week period using a weekly timestep. RESULTS AND CONCLUSIONS Results of the loops that matter analysis showed that from the onset of the poultry production, disease prevention at different growth stages of the chicken (especially for day-old chicks) via vaccination is a critical driver of change that has a high but short-lived dominance. Beyond the grower stage, the changes in the unit price of eggs have a relatively higher and longer influence on production dynamics than changes in the unit price of poultry meat. Moreover, the results suggest that a focus only on meat production is the most profitable strategy compared to production strategies that focus only on egg production or a mix of egg and meat production. SIGNIFICANCE The findings of this paper extend the literature on drivers of change in the farming system by stressing the need to assess how these drivers evolve. The application of the loops that matter analysis in system dynamics modelling provides a framework for analysing the evolution of drivers of change in farming system

    Identifying the precursors of vulnerability in agricultural value chains: A system dynamics approach

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    Conventional approaches for assessing supply chain vulnerability do not capture endogenous disruptions emanating from chain actors’ decisions that might increase value chain vulnerability. These approaches adopt a reactive analytical explanation of vulnerability, rather than one that considers issues of feedback effects. To address this issue, this paper adopts a system dynamics modelling approach to identify the precursors of vulnerabilities in Ghana’s cocoa value chain. The paper assesses the vulnerability levels of the cocoa value chain by adjusting the baseline values of several key parameters that can be influenced by chain actors. Results of the sensitivity analyses indicate that the precursors of vulnerability situated upstream of the cocoa value chain have varying impacts on chain vulnerability, but the same magnitude of effect on the vulnerability levels of chain actors. However, precursors of vulnerability that are situated midstream of the cocoa value chain have an unequal magnitude of effect on the vulnerability levels of chain actors. Results suggest that policies governing cocoa trading can become countervailing factors that obstruct the government’s call for upgrading along the cocoa value chain. The system dynamics model presented here enables a proactive assessment of vulnerability which can facilitate collaborative planning among stakeholders in the value chain

    Ex-ante impact of on-farm diversification and forward integration on agricultural value chain resilience: A system dynamics approach

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    Objective This paper examines the ex-ante impacts of on-farm diversification and forward integration strategies on agricultural value chain resilience, with an empirical focus on Ghana’s cocoa value chain. Method System dynamics modelling was used to explore five scenarios involving variable-input on-farm diversification pursued by cocoa farmers in Ghana and the simultaneous adoption of forward integration strategies by Ghana and Cote d’Ivoire. Results and Conclusions An adaptive strategy involving the simultaneous pursuit of variable-input on-farm diversification and a cooperative forward integration strategy by both Ghana and Cote d’Ivoire was found to result in the highest level of resilience. Under such an adaptive strategy, in-country processors will be the most impacted when the level of safety stocks are below 25% of the average stock level during the period of losses in raw material production. Significance The findings suggest that a policy direction that supports on-farm diversification and in-country processing enhances the aggregate resilience of the cocoa value chain, irrespective of the forward integration strategy adopted by Cote d’Ivoire
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