5,215 research outputs found

    Why diversify annual biomass production for energy – exemplified by green house gas emissions from the Danish IBUS bioethanol production concept

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    There is a need for integrating the biomass starting point into the energy manufacturing steps. It will secure that bioenergy is produced with limited use of non-renewable fossil fuel to secure that in the application of biomass a net emission reduction of green house gasses take place along the whole chain. Intercropping, defined as the cultivation of two or more species simultaneously on the same area of land, is an traditional practice still widespread in the tropics and common in developed countries before the ‘fossilization’ of agriculture. This cropping strategy is based on the manipulation of plant interactions in time and space to optimize resource use and productivity. It is regarded as the practical application of basic ecological principles such as diversity, competition and facilitation (Hauggaard-Nielsen et al., 2007). Cereal-legume annual intercropping show the possibility to increase input of leguminous symbiotic nitrogen (N) fixation into cropping systems reducing the need for fertilizer N applications (Jensen, 1996). Moreover, less need for pesticides are obtained due to improved competition towards weeds (Hauggaard-Nielsen et al., 2001) and less general damages on intercropped species by pest and disease organisms (Hauggaard-Nielsen et al., 2007). Intercropping is a more adaptive management practice as compared to the present arable crop rotations consisting mainly of sole crops. Perennials like clover-grass intercrops or mixtures are obviously more diversified than traditional annual crops. Clover-grass leys are important in many agroecosystems today due to quality as feed for livestock, a high dry matter production (10 t ha-1 yr-1 unfertilized, where 95% of the N accumulation is N2 fixed by clover (Jørgensen et al., 1999) providing a nitrogen-rich residue, which may significantly reduce fertilizer requirements for the succeeding crop when mineralized (Hauggaard-Nielsen et al., 1998). Furthermore, clover-grass lays can be harvested several times a year and processed to ethanol throughout the year. It is very much questioned whether bioethanol is a sustainable energy resource that can offer environmental and long-term economic advantages over fossil fuels, like gasoline or diesel. The aim of the present presentation is to debate the substitution of fossil fuels by crop biomass requiring the right selection of plant species according not only to chemical quality for efficient conversion but also to secure the development of ecologically benign farming system including biomass for energy

    Danish Sector Guide for Calculation of the Actual Energy Consumption

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    Nedbrydning af bentazon og phenoxysyrer i sandfiltre

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    Potential bioethanol and biogas production using lignocellulosic biomass from winter rye, oilseed rape and faba bean

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    To meet the increasing need for bioenergy several raw materials have to be considered for the production of e.g. bioethanol and biogas.In this study, three lignocellulosic raw materials were studied, i.e. (1) winter rye straw (Secale cereale L), (2) oilseed rape straw (Brassica napus L.) and (3) faba bean straw (Viciafaba L.). Their composition with regard to cellulose, hemicellulose, lignin, extractives and ash was evaluated, as well as their potential as raw materials for ethanol and biogas production. The materials were pretreated by wet oxidation using parameters previously found to be optimal for pretreatment of corn stover (195 1C, 15 min, 2 g l_1 Na2CO3 and 12 bar oxygen). It was shown that pretreatment was necessary for ethanol production from all raw materials and gave increased biogas yield from winter rye straw. Neither biogas productivity nor yield from oilseed rape straw or faba bean straw was significantly affected by pretreatment. Ethanol was produced by the yeast Saccharomyces cerevisiae during simultaneous enzymatic hydrolysis of the solid material after wet oxidation with yields of 66%, 70% and 52% of theoretical for winter rye, oilseed rape and faba bean straw, respectively. Methane was produced with yields of 0.36, 0.42 and 0.44 l g_1 volatile solids for winter rye, oilseed rape and faba bean straw, respectively, without pretreatment of the materials. However, biogas productivity was low and it took over 50 days to reach the final yield. It could be concluded that all three materials are possible raw materials for either biogas or ethanol production; however, improvement of biogas productivity or ethanol yield is necessary before an economical process can be achieved. 2007 Elsevier Ltd. All rights reserved

    En svensk konstskatt i fara

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    Svenska konstskatter i fara Tusentals verk försvunna i landets kommuner Skulpturer i skolkorridorer och tavlor på tjänstemannarum. Vår offentliga konst, finansierad av skattepengar, är ett museum dit ingen behöver lösa inträde. Men konst för miljarder riskerar att gå förlorad och antalet försvunna verk är alarmerande. Kontrollen över kommunernas konstsamlingar brister på flera punkter. Enligt vår enkätundersökning som skickats till samtliga 290 kommuner, är det mer än tredjedel av de 192 som svarade som inventerar sällan, och inte har sett över sin konstsamling på fem år eller mer. Elva kommuner vet inte ens när konsten senast setts över. Många vet heller inte hur mycket konst som saknas. Enligt vår undersökning slarvas en del bort, hamnar i förråd och glöms bort, eller stjäls. – Det är vårt gemensamma kulturarv, man ska vara rädd om det, säger Jan Dahlqvist, som är konstarkivarie i Göteborg. Ett intressant exempel är Stockholm som i dag saknar 6 700 verk av 32 000. – Jag vill inte bagatellisera det, men man måste sätta det i ett 120-årsperspektiv. Det mesta är inte stulet, en del har av olika skäl och kanske står på en vind eller i en källare, säger Monika Wallin som är konstantikvarie i Stockholm. I både staten och i Svenska kyrkan finns lagstadgade riktlinjer för hur konst och kulturföremål ska ses över och inventeras. För kommunerna saknas sådana och det är upp till varje kommun att ta hand om sin konst. Men i många kommuner brister det. Varför

    Differentially expressed genes for aggressive pecking behaviour in laying hens

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    BACKGROUND: Aggressive behaviour is an important aspect in the daily lives of animals living in groups. Aggressive animals have advantages, such as better access to food or territories, and they produce more offspring than low ranking animals. The social hierarchy in chickens is measured using the 'pecking order' concept, which counts the number of aggressive pecks given and received. To date, little is known about the underlying genetics of the 'pecking order'. RESULTS: A total of 60 hens from a high feather pecking selection line were divided into three groups: only receivers (R), only peckers (P) and mixed peckers and receivers (P&R). In comparing the R and P groups, we observed that there were 40 differentially expressed genes [false discovery rate (FDR) P < 0.10]. It was not fully clear how the 40 genes regulated aggressive behaviour; however, gene set analysis detected a number of GO identifiers, which were potentially involved in aggressive behavioural processes. These genes code for synaptosomes (GO:0019797), and proteins involved in the regulation of the excitatory postsynaptic membrane potential (GO:0060079), the regulation of the membrane potential (GO:0042391), and glutamate receptor binding (GO:0035254). CONCLUSION: In conclusion, our study provides new insights into which genes are involved in aggressive behaviours in chickens. Pecking and receiving hens exhibited different gene expression profiles in their brains. Following confirmation, the identification of differentially expressed genes may elucidate how the pecking order forms in laying hens at a molecular level
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