87 research outputs found

    Analysis of the overall resource consumption of a Flemish dairy farm using Exergetic Life Cycle Assessment

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    To deal with environmental challenges such as pollution and resource depletion, the potential environmental impact of agricultural products is commonly evaluated using the Life Cycle Assessment (LCA) methodology. For livestock systems, emission-related impacts such as global warming have been frequently studied in this way. During the past decades, intensifi-cation of agricultural systems to improve yields coincided with an increased material and energy throughput. Therefore, we focus on resource consumption in this paper. We applied an exergy-based approach to quantify total resource use and to calculate resource efficien-cies, both at system level and at life cycle level. We have performed a case study of an in-tensive confinement-based dairy farm in Flanders to illustrate our approach

    Resource consumption assessment of Pangasius aquaculture in the Mekong delta, Vietnam

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    In light of full exploitation and overexploitation of marine fish stocks on a global scale, aquaculture has gained prominence to meet the increasing fish demand induced by population growth and rising incomes. Pangasius production in Vietnam is widely known as a success story in the aquaculture sector due to a tremendous expansion by volume and value in recent years. However, a growing concern has arisen about the environmental sustainability of this system, particularly in terms of resource extraction. We addressed this issue here by expressing all resources in one common unit: Joules of exergy. Exergy is defined as the amount of maximum useful energy obtained from a resource. Analysis using this metric was performed at process level through Exergy Analysis (EA; Table 1) and from a life cycle perspective via quantification of the Cumulative Exergy Extraction from the Natural Environment (CEENE; Figure 1), which was subdivided into seven resource categories. This allows one to identify hotspots over the life cycle stages, including feed production, juvenile production and fish cultivation. Results show that the largest contributors were the feed input (73% of the total CEENE) and the water renewal of the ponds (25%), mainly assigned to the farm phase (90%). Land (62%) and water (31%) account for the main share in the resource footprint, which is reasoned by the agricultural production of the crop-based feed ingredients and the high water exchange in pond farming, respectively. Improvements therefore should focus on lowering water input into the ponds and increasing the efficiency of the feed supply chain. The latter option represents a great challenge while the former could be feasible through the application of a recirculating aquaculture system (RAS). Further research is needed to explore whether RAS is a feasible sustainable alternative. Overall, Vietnamese farm and feed mill managers play a key role in improving the environmental performance of Pangasius products. Focus should not only lay on their own farming and processing, but also on the selection of their feed suppliers

    Shallow whole-genome sequencing of plasma cell-free DNA accurately differentiates small from non-small cell lung carcinoma

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    Background Accurate lung cancer classification is crucial to guide therapeutic decisions. However, histological subtyping by pathologists requires tumor tissue-a necessity that is often intrinsically associated with procedural difficulties. The analysis of circulating tumor DNA present in minimal-invasive blood samples, referred to as liquid biopsies, could therefore emerge as an attractive alternative. Methods Concerning adenocarcinoma, squamous cell carcinoma, and small cell carcinoma, our proof of concept study investigates the potential of liquid biopsy-derived copy number alterations, derived from single-end shallow whole-genome sequencing (coverage 0.1-0.5x), across 51 advanced stage lung cancer patients. Results Genomic abnormality testing reveals anomalies in 86.3% of the liquid biopsies (16/20 for adenocarcinoma, 13/16 for squamous cell, and 15/15 for small cell carcinoma). We demonstrate that copy number profiles from formalin-fixed paraffin-embedded tumor biopsies are well represented by their liquid equivalent. This is especially valid within the small cell carcinoma group, where paired profiles have an average Pearson correlation of 0.86 (95% CI 0.79-0.93). A predictive model trained with public data, derived from 843 tissue biopsies, shows that liquid biopsies exhibit multiple deviations that reflect histological classification. Most notably, distinguishing small from non-small cell lung cancer is characterized by an area under the curve of 0.98 during receiver operating characteristic analysis. Additionally, we investigated how deeper paired-end sequencing, which will eventually become feasible for routine diagnosis, empowers tumor read enrichment by insert size filtering: for all of the 29 resequenced liquid biopsies, the tumor fraction could be increased in silico, thereby "rescuing" three out of five cases with previously undetectable alterations. Conclusions Copy number profiling of cell-free DNA enables histological classification. Since shallow whole-genome sequencing is inexpensive and often fully operational at routine molecular laboratories, this finding has current diagnostic potential, especially for patients with lesions that are difficult to reach

    Reporter gene-expressing bone marrow-derived stromal cells are immune-tolerated following implantation in the central nervous system of syngeneic immunocompetent mice

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    <p>Abstract</p> <p>Background</p> <p>Cell transplantation is likely to become an important therapeutic tool for the treatment of various traumatic and ischemic injuries to the central nervous system (CNS). However, in many pre-clinical cell therapy studies, reporter gene-assisted imaging of cellular implants in the CNS and potential reporter gene and/or cell-based immunogenicity, still remain challenging research topics.</p> <p>Results</p> <p>In this study, we performed cell implantation experiments in the CNS of immunocompetent mice using autologous (syngeneic) luciferase-expressing bone marrow-derived stromal cells (BMSC-Luc) cultured from ROSA26-L-S-L-Luciferase transgenic mice, and BMSC-Luc genetically modified using a lentivirus encoding the enhanced green fluorescence protein (eGFP) and the puromycin resistance gene (Pac) (BMSC-Luc/eGFP/Pac). Both reporter gene-modified BMSC populations displayed high engraftment capacity in the CNS of immunocompetent mice, despite potential immunogenicity of introduced reporter proteins, as demonstrated by real-time bioluminescence imaging (BLI) and histological analysis at different time-points post-implantation. In contrast, both BMSC-Luc and BMSC-Luc/eGFP/Pac did not survive upon intramuscular cell implantation, as demonstrated by real-time BLI at different time-points post-implantation. In addition, ELISPOT analysis demonstrated the induction of IFN-γ-producing CD8+ T-cells upon intramuscular cell implantation, but not upon intracerebral cell implantation, indicating that BMSC-Luc and BMSC-Luc/eGFP/Pac are immune-tolerated in the CNS. However, in our experimental transplantation model, results also indicated that reporter gene-specific immune-reactive T-cell responses were not the main contributors to the immunological rejection of BMSC-Luc or BMSC-Luc/eGFP/Pac upon intramuscular cell implantation.</p> <p>Conclusion</p> <p>We here demonstrate that reporter gene-modified BMSC derived from ROSA26-L-S-L-Luciferase transgenic mice are immune-tolerated upon implantation in the CNS of syngeneic immunocompetent mice, providing a research model for studying survival and localisation of autologous BMSC implants in the CNS by real-time BLI and/or histological analysis in the absence of immunosuppressive therapy.</p

    Cost-effectiveness of stereotactic body radiation therapy versus video assisted thoracic surgery in medically operable stage I non-small cell lung cancer: A modeling study

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    Objectives: Stage I non-small cell lung cancer (NSCLC) can be treated with either Stereotactic Body Radiotherapy (SBRT) or Video Assisted Thoracic Surgery (VATS) resection. To support decision making, not only the impact on survival needs to be taken into account, but also on quality of life, costs and cost-effectiveness. Therefore, we performed a cost-effectiveness analysis comparing SBRT to VATS resection with respect to quality adjusted life years (QALY) lived and costs in operable stage I NSCLC. Materials and methods: Patient level and aggregate data from eight Dutch databases were used to estimate costs, health utilities, recurrence free and overall survival. Propensity score matching was used to minimize selection bias in these studies. A microsimulation model predicting lifetime outcomes after treatment in stage I NSCLC patients was used for the cost-effectiveness analysis. Model outcomes for the two treatments were overall survival, QALYs, and total costs. We used a Dutch health care perspective with 1.5 % discounting for health effects, and 4 % discounting for costs, using 2018 cost data. The impact of model parameter uncertainty was assessed with deterministic and probabilistic sensitivity analyses. Results: Patients receiving either VATS resection or SBRT were estimated to live 5.81 and 5.86 discounted QALYs, respectively. Average discounted lifetime costs in the VATS group were €29,269 versus €21,175 for SBRT. Difference in 90-day excess mortality between SBRT and VATS resection was the main driver for the difference in QALYs. SBRT was dominant in at least 74 % of the probabilistic simulations. Conclusion: Using a microsimulation model to combine available evidence on survival, costs, and health utilities in a cost-effectiveness analysis for stage I NSCLC led to the conclusion that SBRT dominates VATS resection in the majority of simulations
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