160 research outputs found

    Life cycle assessment of synthetic natural gas production from different CO2 sources: A cradle⇂to-gate study

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    Fuel production from hydrogen and carbon dioxide is considered an attractive solution as long‐term storage of electric energy and as temporary storage of carbon dioxide. A large variety of CO2 sources are suitable for Carbon Capture Utilization (CCU), and the process energy intensity depends on the separation technology and, ultimately, on the CO2 concentration in the flue gas. Since the carbon capture process emits more CO2 than the expected demand for CO2 utilization, the most sustainable CO2 sources must be selected. This work aimed at modeling a Power‐to‐Gas (PtG) plant and assessing the most suitable carbon sources from a Life Cycle Assessment (LCA) perspective. The PtG plant was supplied by electricity from a 2030 scenario for Italian electricity generation. The plant impacts were assessed using data from the ecoinvent database version 3.5, for different CO2 sources (e.g., air, cement, iron, and steel plants). A detailed discussion on how to handle multi‐functionality was also carried out. The results showed that capturing CO2 from hydrogen production plants and integrated pulp and paper mills led to the lowest impacts concerning all investigated indicators. The choice of how to handle multi‐functional activities had a crucial impact on the assessment

    Evaluation of adoption potential of modern technologies in potato value chain by smallholder farmers in Kenya: Nyandarua County pilot case study.

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    In Kenya, smallholder potato farmers endeavor to increase their production through various approaches, most commonly by expanding areas under production and repeatedly planting potato on the same site, with the latter resulting in build-up of diseases. Compounded with limited access to options to improve productivity, these farmers yield less than 10 t ha, much below realistic yields of 20 to 30 t ha. In an attempt to address these constraints, a study in the framework of the pilot project Potato Initiative Africa lead by International Potato Center (CIP) evaluated modern interventions to improve yields and reduce harvest and post-harvest losses along the production chain

    Are dormancy management and physiological age the achilles' heel of aeroponic minituber production in seed potato value chains in SSA?

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    Scarcity of good quality seed is major obstacle to expanded potato (Solanum tuberosum L.) production in sub-saharan Africa (SSA). Constraints in availability and supply of seed potato are partly attributable to challenges in production of pre-basic which is an intermediary step necessary in production of seed tubers in the seed potato value chain. Aeroponic minutuber production is a relatively recent technology that has the potential to break the seed potato bottleneck in many SSA countries due to several advantages that it holds especially those related to high multiplication rates; typically (1:50-100) that arise from sequential harvesting. There are, however, a number of potential challenges which, if not addressed, can contribute to non attainment of the projected increases in seed availability and not only mess up the 3 generation (3G) revolution strategy of boosting seed tuber production in SSA but also jeopardize the adoption of the technology. Besides problems associated with failure of electricity supply and management of nutrition, the Achilles‘ heel of aeroponic minituber production is probably the large variation in physiological age of resulting tubers due to sequential harvesting that takes place over several months during the production cycle. In the absence of cold storage facilities which are few and beyond the reach of many pre-basic seed potato growers in many SSA countries, harvested minitubers can either be at dormant, apical dominance, multiple sprouting or senile stage when they are required for planting with significant impacts on subsequent yields. This paper discusses the problems associated with physiological age in seed tuber systems based on aeroponic minitubers and proposes some approaches that may overcome these challenges to ensure that the promise of aeroponic minituber production is realized. The proposed approaches include the strategic application of dormancy inhibiting and dormancy promoting substances at various stages of aeroponic minituber production combined with the use of low cost storage systems such as the diffused light storage technology depending on the dormancy period of the variety (ies) being grown

    Genome-wide mapping of Quantitative Trait Loci for fatness, fat cell characteristics and fat metabolism in three porcine F2 crosses

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    <p>Abstract</p> <p>Background</p> <p>QTL affecting fat deposition related performance traits have been considered in several studies and mapped on numerous porcine chromosomes. However, activity of specific enzymes, protein content and cell structure in fat tissue probably depend on a smaller number of genes than traits related to fat content in carcass. Thus, in this work traits related to metabolic and cytological features of back fat tissue and fat related performance traits were investigated in a genome-wide QTL analysis. QTL similarities and differences were examined between three F<sub>2 </sub>crosses, and between male and female animals.</p> <p>Methods</p> <p>A total of 966 F<sub>2 </sub>animals originating from crosses between Meishan (M), Pietrain (P) and European wild boar (W) were analysed for traits related to fat performance (11), enzymatic activity (9) and number and volume of fat cells (20). Per cross, 216 (M × P), 169 (W × P) and 195 (W × M) genome-wide distributed marker loci were genotyped. QTL mapping was performed separately for each cross in steps of 1 cM and steps were reduced when the distance between loci was shorter. The additive and dominant components of QTL positions were detected stepwise by using a multiple position model.</p> <p>Results</p> <p>A total of 147 genome-wide significant QTL (76 at P < 0.05 and 71 at P < 0.01) were detected for the three crosses. Most of the QTL were identified on SSC1 (between 76-78 and 87-90 cM), SSC7 (predominantly in the MHC region) and SSCX (in the vicinity of the gene <it>CAPN6</it>). Additional genome-wide significant QTL were found on SSC8, 12, 13, 14, 16, and 18. In many cases, the QTL are mainly additive and differ between F<sub>2 </sub>crosses. Many of the QTL profiles possess multiple peaks especially in regions with a high marker density. Sex specific analyses, performed for example on SSC6, SSC7 and SSCX, show that for some traits the positions differ between male and female animals. For the selected traits, the additive and dominant components that were analysed for QTL positions on different chromosomes, explain in combination up to 23% of the total trait variance.</p> <p>Conclusions</p> <p>Our results reveal specific and partly new QTL positions across genetically diverse pig crosses. For some of the traits associated with specific enzymes, protein content and cell structure in fat tissue, it is the first time that they are included in a QTL analysis. They provide large-scale information to analyse causative genes and useful data for the pig industry.</p
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