52 research outputs found

    Eco-Efficiency of Forage Production in Northern Germany

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    A 2-year field experiment was conducted at two sites in Schleswig-Holstein, northern Germany, to quantify and evaluate the carbon footprint of arable forage cropping systems (continuous silage maize, maize-wheat-grass rotation, perennial ryegrass ley) as affected by N fertilizer type and N amount. Total greenhouse gas emission showed a linear increase with N application, with mineral N supply resulting in a higher slope. Product carbon footprint ranged between -66 and 119 kg CO2eq/(GJ NEL) and revealed a quadratic or linear response to fertilizer N input, depending on the cropping system. At N input required for achieving maximum energy yield, perennial ryegrass caused lower emission per product unit than continuous maize or the maize-wheat-grass rotation. The data indicate potential for sustainable intensification when crop management options are adopted to increase resource use efficiency

    Lachgasemission und Nitratauswaschung verschiedener Futterproduktionssysteme in AbhÀngigkeit von der Vornutzung

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    Intensified agriculture is often associated with nitrous oxide (N2O) emissions and nitrate (NO3) leaching losses into groundwater due to high application rates of N-fertilizer, increasing maize cultivation and ploughing up permanent grassland. N2O is an important anthropogenic greenhouse gas and agriculture is one of the main polluters. NO3 leaching endangers groundwater quality. In a field experiment on the organically managed farm “Lindhof” in Northern Germany three different forage production systems (1. crop rotation, 2. continuous silage maize 3. permanent grassland) were established parallelly after a) ploughing up permanent grassland and b) longtime arable use. N2O emissions were measured weekly over the two-year experimental period. Soil water samples were taken over the leaching season (Oct-Mar) once a week and analysed for N-content. The production systems “crop rotation” and “continuous maize” showed significant higher amounts of N2O emissions and NO3 leaching than the newly established or resown grassland. In the system “crop rotation”, maize after grass-clover had the highest emissions, because of high N-mineralization of clover residues, both during and after growing season. Long-term cropping history and manure application had no significant effects, but on plots established on former grassland, emissions and leaching tended to be higher

    Yield Progress in Forage Maize in NW Europe—Breeding Progress or Climate Change Effects?

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    Yield increases in forage maize (Zea mays L.) in NW Europe over time are well documented. The driving causes for these, however, remain unclear as there is little information available regarding the role of plant traits triggering this yield progress. Ten different hybrids from the same maturity group, which have typically been cultivated in Northwest Germany from 1970 to recent and are thus representing breeding progress over four decades, were selected for a 2-year field study in northern Germany. Traits that were investigated included leaf area index, leaf architecture, photosynthesis, radiation use efficiency, root mass, root length density, and turnover. Based on a mixed model analysis with these traits as co-variates, parameters related to leaf characteristics, in particular the number and length of leaves, the radiation use efficiency, and the leaf orientation, were identified as most influential on the yield progress (0.13 tons ha-1 year-1). In contrast to our hypothesis, root biomass only increased negligibly in newer hybrids compared to older ones, confirming the ‘functional equilibrium’ theory for high input production systems. Due to an abundance of nutrients and water in such high input systems, there is no incentive for breeders to select for carbon partitioning toward the rooting system. Breeding evidence to increase forage quality were also negligible, with no change in cob starch concentration, forage digestibility, nor NDF content and NDF digestibility. The observed increase in yield over the last four decades is due to a combination of increased temperature sums (~240 GDD within 40 years), and a higher radiation interception and radiation use efficiency. This higher radiation interception was driven by an increased leaf area index, with a higher number of leaves (16 instead of 14 leaves within 40 years) and longer leaves of newer compared to older hybrids. Future selection and adaptation of maize hybrids to changing environmental conditions are likely to be the key for high productivity and quality and for the economic viability of maize growing and expansion in Northern Europe

    Differential regulation of interleukin-6 expression in human fibroblasts by tumor necrosis factor-α and lymphotoxin

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    AbstractThe treatment of human diploid fibroblasts with tumor necrosis factor (TNP)-α and with lymphotoxin (LT) is associated with induction of interleuk-in-6 (IL-6) transcripts with TNF-α being 10-fold more potent than LT. Here we report on the TNF-α/LT-induced signaling mechanisms responsible for the regulation of IL-6 gene expression in these cells. Run-on assays demonstrated that both TNF-α and LT increase IL-6 mRNA levels by transcriptional activation of this gene. Stability studies of IL-6 transcripts in fibroblasts showed that TNF-α delayed IL-6 mRNA decay but not LT. The induction of IL-6 transcripts by TNF-α and LT was not inhibited by the isoquinoline sulfonamide derivative H7. Similarly, depletion of protein kinase C (PKC) by 12-O-tetradecanoyl-phorbol 13-acetate (TPA) did not change the ability of TNF-α and LT to induce IL-6 transcripts, demonstrating that stimulation by these agents may not be mediated by activation of PKC. Stimulation of IL-6 transcripts in fibroblasts did also not require new protein synthesis as exposure to the protein synthesis inhibitor cycloheximide (CHX) enhanced accumulation of IL-6 mRNA in the presence or absence of TNF-α or LT

    N-Umsatz, Spurengasemissionen und ProduktivitÀt von Fruchtfolgen zur Biogasproduktion in einer Kalkmarsch Schleswig-Holsteins

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    Aufgrund des bisher wenig untersuchten Agrarlandschaftsraumes als auch neuartiger BiogasgĂ€rreste ist der Effekt der Biogasnutzung auf den Stoffhaushalt von Marschstandorten schwer zu quantifizieren. Auf einem noch nicht entkalkten Marschstandort Nordfries-lands, Schleswig-Holstein, wurden in einem Parzellenversuch mehrjĂ€hrige Untersuchungen zur N-DĂŒngewirksamkeit und Spurengasemissionen (N2O, NH3) bei DĂŒngung mit MineraldĂŒnger (KAS) und BiogasgĂ€rresten durchgefĂŒhrt. Die N-DĂŒnger wurden zur Produktion von Silomais, Weidelgras und GPS-Weizen als Biogassubstrat genutzt. Biogas-gĂ€rreste wurden mit SchleppschlĂ€uchen ausgebracht. Bei Verwendung des MineraldĂŒngers erzielten Maismonokultur, Ackergras sowie eine Fruchtfolge (Mais-Weizen-Welsches Weidelgras) etwa gleich hohe ErtrĂ€ge (ca. 30 t TM ha 1 2a-1). Bei Weizen und Ackergras fĂŒhrte die DĂŒngung mit BiogasgĂ€rresten zu deutlich reduzierten ErtrĂ€gen. NH3-Emissionen lagen aufgrund hoher Windgeschwin- digkeiten höher als in anderen Regionen Schleswig-Holsteins, wobei Ackergras bei weitem die höchsten (80 kg N ha-1 2a-1) und Maismonokultur die geringsten (20 kg N ha-1 2a-1) kumulierten Verluste aufwies. Ohne signifikante Unterschiede zwischen den N-DĂŒngern lagen kumulierte N2O-Emissionen mit 1–5 kg N ha-1 a-1 trotz betrĂ€chtlicher N-Aufwand-mengen und des tonreichen Bodens relativ niedrig

    Assessing nitrous oxide emissions and productivity of cropping systems for biogas production using digestate and mineral fertilisation in a coastal marsh site

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    Significant greenhouse gas emissions during substrate cultivation reduces the potential environmental benefits of biogas production. This study investigates the productivity of different cropping systems and their environmental impact in terms of nitrous oxide (N2O) emissions under the environmental conditions of the coastal marsh regions (Northern Germany) with heavy clay soils, in a 2-year field trial (April 2009-March 2011). Treatments included four cropping systems (perennial ryegrass (Lolium perenne, PR) ley, continuous maize (Zea mays), a rotation (CR1) of spring wheat (Triticum aestivum), Italian ryegrass (Lolium multiflorum, IR) and maize, and a rotation (CR2) of maize, winter wheat and IR; two sources of N (nitrogen) fertilizers (calcium ammonium nitrate, and biogas residue (BR)), and three levels of N fertilizer applications (control, moderate, high). Nitrous oxide emissions were determined for the unfertilized and highly fertilized cropping systems comprising PR ley, CR1 and CR2. Cumulative annual N2O emissions varied across the treatments, ranging from 0.82 to 3.4 kg N2O-N ha−1 year−1. Under high N fertilizer applications, PR ley incurred higher N2O-N losses compared to other tested cropping systems, and IR cover crop caused relatively high N2O-N emissions in a short vegetation period. The study observed wide range of yield-scaled emissions (0.00–5.60 kg N2O-N (Mg DM)−1) for different crops, emphasizing the variability in N2O emissions linked to cropping systems. The N2O-N emission factors for the three cropping systems were found to be low to moderate for all treatments, ranging from 0.03% to 0.53% compared to IPCC default Tier 1 N2O-N EFs. The lower emissions in the study were associated with prolonged high soil moisture conditions (water filled pore space >70%.), indicated by its negative correlation with N2O-N fluxes. Low dry matter and N yield of PR and of the wheat-IR sequence after BR application compared to other crops indicated a low N use efficiency. The estimation of N2O-N emissions based on N surplus was not promising specifically for the coastal study site where high groundwater level and organic matter in the soils were the predominant drivers for N2O-N emissions

    N-Umsatz und Spurengasemissionen typischer Biomassefruchtfolgen zur Biogaserzeugung in Norddeutschland

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    Im Rahmen des Verbundprojektes Biogas-Expert an der CAU-Kiel wurden an zwei Standorten Schleswig-Holsteins veschiedene Fruchtfolgen zur Bereitstellung von Biogassubstraten unter Verwendung von BiogasgĂŒllen als N-DĂŒnger durchgefĂŒhrt. Maismonokultur wies die höchsten TrockenmasseertrĂ€ge auf, wobei keine signifikanten Unterschiede in den ErtrĂ€gen zwischen BiogasgĂ€rresten, organischen N-DĂŒngern und mineralischen DĂŒngern ermittelt wurden. WĂ€hrend in Bezug auf die N-DĂŒngeform bei N2O- und Nitratauswaschungsverlusten kein Einfluss der N-Form auf die Höhe der Verluste festgestellt wurde, war die DĂŒngung mit BiogasgĂŒllen mit signifikant erhöhten NH3-Verlusten verknĂŒpft. Eine abschließende Bewertung der Produktionssysteme ist erst durch Analyse der experimentellen Ergebnisse mit einem Systemmodell möglich

    Development and validation of explainable machine learning models for risk of mortality in transcatheter aortic valve implantation: TAVI risk machine scores.

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    AIMS Identification of high-risk patients and individualized decision support based on objective criteria for rapid discharge after transcatheter aortic valve implantation (TAVI) are key requirements in the context of contemporary TAVI treatment. This study aimed to predict 30-day mortality following TAVI based on machine learning (ML) using data from the German Aortic Valve Registry. METHODS AND RESULTS Mortality risk was determined using a random forest ML model that was condensed in the newly developed TAVI Risk Machine (TRIM) scores, designed to represent clinically meaningful risk modelling before (TRIMpre) and in particular after (TRIMpost) TAVI. Algorithm was trained and cross-validated on data of 22 283 patients (729 died within 30 days post-TAVI) and generalisation was examined on data of 5864 patients (146 died). TRIMpost demonstrated significantly better performance than traditional scores [C-statistics value, 0.79; 95% confidence interval (CI)] [0.74; 0.83] compared to Society of Thoracic Surgeons (STS) with C-statistics value 0.69; 95%-CI [0.65; 0.74]). An abridged (aTRIMpost) score comprising 25 features (calculated using a web interface) exhibited significantly higher performance than traditional scores (C-statistics value, 0.74; 95%-CI [0.70; 0.78]). Validation on external data of 6693 patients (205 died within 30 days post-TAVI) of the Swiss TAVI Registry confirmed significantly better performance for the TRIMpost (C-statistics value 0.75, 95%-CI [0.72; 0.79]) compared to STS (C-statistics value 0.67, CI [0.63; 0.70]). CONCLUSION TRIM scores demonstrate good performance for risk estimation before and after TAVI. Together with clinical judgement, they may support standardised and objective decision-making before and after TAVI

    Whole exome resequencing reveals recessive mutations in TRAP1 in individuals with CAKUT and VACTERL association

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    Congenital abnormalities of the kidney and urinary tract (CAKUT) account for approximately half of children with chronic kidney disease and they are the most frequent cause of end-stage renal disease in children in the US. However, its genetic etiology remains mostly elusive. VACTERL association is a rare disorder that involves congenital abnormalities in multiple organs including the kidney and urinary tract in up to 60% of the cases. By homozygosity mapping and whole exome resequencing combined with high-throughput mutation analysis by array-based multiplex PCR and next-generation sequencing, we identified recessive mutations in the gene TNF receptor-associated protein 1 (TRAP1) in two families with isolated CAKUT and three families with VACTERL association. TRAP1 is a heat shock protein 90-related mitochondrial chaperone possibly involved in antiapoptotic and endoplasmic reticulum-stress signaling. Trap1 is expressed in renal epithelia of developing mouse kidney E13.5 and in the kidney of adult rats, most prominently in proximal tubules and in thick medullary ascending limbs of Henle’s loop. Thus, we identified mutations in TRAP1 as highly likely causing CAKUT or CAKUT in VACTERL association
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