7 research outputs found

    Supply Chain Uncertainties of Small-Scale Coffee Husk-Biochar Production for Activated Carbon in Vietnam

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    Between 2014 and 2019, an innovative small-pyrolysis system (the PPV300) using agrowaste as feedstock was transferred and adapted from Switzerland to Vietnam by a United Nations Industrial Development Organization (UNIDO) project. The coffee husk resulting from the processing of coffee beans is usually disposed of in Vietnam or burned inefficiently to dry coffee beans. Small-scale pyrolysis of coffee husk using the PPV300 avoids smoke emissions and local air pollution while providing an energy source for coffee drying and biochar as a by-product. This paper investigates the uncertainties in the “coffee husk to activated carbon” supply chain in Vietnam and discusses the pros and cons of different supply chain setups using a framework derived by Chopra and Meindl (2013). According to the analysis, a number of actors (an intermediary without previous direct involvement in the coffee supply chain, a coffee processor, or a hybrid between farm and processor), each with advantages and disadvantages, would be suitable from a supply chain perspective to attain an efficient strategy that would keep the price of the biochar low. However, in order to be attractive for one activated carbon producer, several PPV300 systems are needed to reach a significant economy of scale. Sufficient husk sourcing and storage capacity is also needed. If the purpose is simply to produce biochar for activated carbon, processors and intermediaries could consider a simpler and cheaper design than the PPV300. In conclusion, supply chain uncertainties and economic viability can be optimized when the PPV300 is used by coffee processors or intermediaries, who are able to make use of the co-products generated (biochar, heat, and wood vinegar). In addition to its financial viability, all of the other co-benefits of this technology should be taken into consideration (reduced smoke and environmental pollution, avoided health costs, greenhouse gas savings, etc.) for a proper assessment of its economic attractiveness

    Brown fat does not cause cachexia in cancer patients: A large retrospective longitudinal FDG-PET/CT cohort study

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    BACKGROUND Brown adipose tissue (BAT) is a specialized form of adipose tissue, able to increase energy expenditure by heat generation in response to various stimuli. Recently, its pathological activation has been implicated in the pathogenesis of cancer cachexia. To establish a causal relationship, we retrospectively investigated the longitudinal changes in BAT and cancer in a large FDG-PET/CT cohort. METHODS We retrospectively analyzed 13 461 FDG-PET/CT examinations of n = 8 409 patients at our institution from the winter months of 2007-2015. We graded the activation strength of BAT based on the anatomical location of the most caudally activated BAT depot into three tiers, and the stage of the cancer into five general grades. We validated the cancer grading by an interreader analysis and correlation with histopathological stage. Ambient temperature data (seven-day average before the examination) was obtained from a meteorological station close to the hospital. Changes of BAT, cancer, body mass index (BMI) and temperature between the different examinations were examined with Spearman's test and a mixed linear model for correlation, and with a causal inference algorithm for causality. RESULTS We found n = 283 patients with at least two examinations and active BAT in at least one of them. There was no significant interaction between the changes in BAT activation, cancer burden or BMI. Temperature changes exhibited a strong negative correlation with BAT activity (ϱ = -0.57, p<0.00001). These results were confirmed with the mixed linear model. Causal inference revealed a link of Temperature ➜ BAT in all subjects and also of BMI ➜ BAT in subjects who had lost weight and increased cancer burden, but no role of cancer and no causal links of BAT ➜ BMI. CONCLUSIONS Our data did not confirm the hypothesis that BAT plays a major role in cancer-mediated weight loss. Temperature changes are the main driver of incidental BAT activity on FDG-PET scans

    In-depth analysis of interreader agreement and accuracy in categorical assessment of brown adipose tissue in (18)FDG-PET/CT

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    PURPOSE: To evaluate the interreader agreement of a three-tier craniocaudal grading system for brown fat activation and investigate the accuracy of the distinction between the three grades. MATERIALS AND METHODS: After IRB approval, 340 cases were retrospectively selected from patients undergoing (18)FDG-PET/CT between 2007 and 2015 at our institution, with 85 cases in each grade and 85 controls with no active brown fat. Three readers evaluated all cases independently. Furthermore standardized uptake values (SUV) measurements were performed by two readers in a subset of 53 cases. Agreement between the readers was assessed with Cohen's Kappa (k), the concordance correlation coefficient (CCC) and the intraclass correlation coefficient (ICC). Accuracy was assessed with Bland-Altman and receiver operating characteristics (ROC) analysis. A Bonferroni-corrected two-tailed p<0.016 was considered statistically significant. RESULTS: Agreement for BAT grade was excellent by all three metrics with k=0.83-0.89, CCC=0.83-0.89 and ICC=0.91-0.94. Bland-Altman analysis revealed only slight average over- or underestimation (-0.01-0.14) with the majority of disagreements within one grade. ROC analysis yielded slightly less accurate classification between higher vs. lower grades (Area under the ROC curves 0.78-0.84 vs. 0.88-0.92) but no significant differences between readers. Agreement was also excellent for the maximum SUV and the total brown fat volume (k=0.90 and 0.94, CCC=0.93 and 0.99, ICC=0.96 and 0.99), but Bland-Altman plots revealed a tendency to underestimate activity by one of the readers. CONCLUSION: Grading the activation of brown fat by assessment of the most caudally activated depots results in excellent interreader agreement, comparable to SUV measurements

    The transformation and outcome of traditional cassava starch processing in Guangxi, China

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    To improve the resource utilization, reduce the pollution generation, and increase the economic benefits of enterprises, a cleaner process to produce cassava starch was proposed based on potato starch processing, and it was applied to the transformation of a traditional cassava starch processing factory in the Guangxi Province in China. The transformation involves the implementation of several new techniques/facilities, including a rasper, horizontal centrifuge, and hydrocyclone. Based on the transformation, typical cassava starch factories in Guangxi were evaluated. The results show that, through the application of a series of cleaner techniques/facilities, the starch recovery rate increased to 84.5%. The water consumption, wastewater generation, and chemical oxygen demand generation decreased by 53.8%, 49.0%, and 20.7%, respectively. Based on the cleaner process, the wastewater can be treated to meet the national discharge standard by using common wastewater treatment technology

    Brown fat does not cause cachexia in cancer patients: A large retrospective longitudinal FDG-PET/CT cohort study

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    Background Brown adipose tissue (BAT) is a specialized form of adipose tissue, able to increase energy expenditure by heat generation in response to various stimuli. Recently, its pathological activation has been implicated in the pathogenesis of cancer cachexia. To establish a causal relationship, we retrospectively investigated the longitudinal changes in BAT and cancer in a large FDG-PET/CT cohort. Methods We retrospectively analyzed 13 461 FDG-PET/CT examinations of n = 8 409 patients at our institution from the winter months of 2007–2015. We graded the activation strength of BAT based on the anatomical location of the most caudally activated BAT depot into three tiers, and the stage of the cancer into five general grades. We validated the cancer grading by an interreader analysis and correlation with histopathological stage. Ambient temperature data (seven-day average before the examination) was obtained from a meteorological station close to the hospital. Changes of BAT, cancer, body mass index (BMI) and temperature between the different examinations were examined with Spearman’s test and a mixed linear model for correlation, and with a causal inference algorithm for causality. Results We found n = 283 patients with at least two examinations and active BAT in at least one of them. There was no significant interaction between the changes in BAT activation, cancer burden or BMI. Temperature changes exhibited a strong negative correlation with BAT activity (ϱ = -0.57, p<0.00001). These results were confirmed with the mixed linear model. Causal inference revealed a link of Temperature ➜ BAT in all subjects and also of BMI ➜ BAT in subjects who had lost weight and increased cancer burden, but no role of cancer and no causal links of BAT ➜ BMI. Conclusions Our data did not confirm the hypothesis that BAT plays a major role in cancer-mediated weight loss. Temperature changes are the main driver of incidental BAT activity on FDG-PET scans. © 2020 Public Library of ScienceISSN:1932-620
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