48 research outputs found

    Carbon balance of a rain-fed maize field

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    This thesis analyses micrometeorological measurements carried out from June 2004 until October 2006 in the framework of the INTERREG IIIa Project Nr. 3c.10 ”Impacts of climate change on vegetation in the Upper Rhine Valley”. The study addresses the exchange processes of carbon, water and energy of a rain-fed field under maize-fallow rotation. Measurements with an ultrasonic anemometer-thermometer, an open-path CO2/H2O infra-red gas analyser and of the meteorological drivers such as photosynthetic photon flux density (PPFD), temperature and precipitation give insight in the interaction between atmosphere, soil and vegetation. Energy balance considerations show similar patterns of the energy flux densities for vegetation periods and bare field conditions. Energy balance closure is 80 % and 52 %, respectively. A closer look shows a clear diurnal pattern with bad closure during nighttime and an increasing closure fraction during daytime, in fact resulting in an overshooting in late afternoon. Evapotranspiration shows a clear seasonal pattern with maximum values of ~3.5 mm d-1 reached in mid-July. The total water need for the three subsequent years is 321, 397, and 422 mm per kg kernels (yield). The water use efficiency shows a strong relationship with PPFD and the amount of biomass. The focus of the study is on carbon balance. During the three subsequent vegetation periods 930, 785, and 841 g C m-2 are sequestered, respectively. The yield is 455, 417, and 340 g C m-2. About 40 % of the biomass remaining on the field at harvest are decomposed during the dormant season. The resulting numbers for the carbon balance show a ”yearly” sink of this agroecosystem of ~250 g C m-2. Besides unlimited photosynthetic active radiation the combination of the optimal temperature range with the needed precipitation amount corresponding to the need of the actual growth stage are essential for optimal maize growth

    Heterotrophic and rhizospheric respiration in coniferous forest soils along a latitudinal gradient

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    Publisher Copyright: © 2022Northern forest soils are a major carbon (C) reservoir of global importance. To estimate how the C balance in these soils will change, the roles of tree roots and soil microbes in C balance should first be decoupled. This study determined how the activity of heterotrophs and tree roots together with root-associated microbes in the rhizosphere varies in coniferous forest soils in boreal, hemiboreal, and temperate climates along a latitudinal gradient using a trenching approach. We created experimental plots without living tree roots, measured soil respiration (CO2 efflux) from these and from unmanipulated plots using the chamber technique, and partitioned the efflux into root-rhizosphere (RR) and heterotrophic (RH) respiration. The share of RR in ecosystem gross primary production (GPP) decreased from north to south in the Scots pine (Pinus sylvestris L.) and the Norway spruce (Picea abies (L.) Karst.) forests, with the exception of a mixed site, where the share of RR in GPP varied strongly between the years. RR per ground area and per root biomass were mainly independent of climate within the gradient. RH per ground area increased from north to south with temperature, while RH per soil C did not change with temperature. Soil moisture did not significantly affect the respiration components in the northernmost site, whereas soil moisture was positively connected with RH and negatively with RR in other Scots pine sites and positively connected with RR in pure Norway spruce stands. The dynamic ecosystem model LPJ-GUESS was able to capture the seasonal dynamics of RH and RR at the sites, but overall accuracy varied markedly between the sites, as the model underestimated RH in the southern site and RR elsewhere. Our study provides knowledge about the nature of soil respiration components. The valuable insights can be used in more accurate land-ecosystem modelling of forest ecosystems.Peer reviewe

    Antimicrobial use for selected diseases in cats in Switzerland.

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    BACKGROUND Antibiotic use in human and veterinary medicine is considered a main driver of antimicrobial resistance. Although guidelines to promote appropriate use of antimicrobials in veterinary patients have been developed, antibiotic overprescription is assumed to be a common problem. The goal of this study was to investigate antimicrobial use in cats in Switzerland with acute upper respiratory tract disease (aURTD), feline lower urinary tract disease (FLUTD) and abscesses, and to assess compliance of prescription with consensus guidelines. A total of 776 cases (aURTD, n = 227; FLUTD, n = 333; abscesses, n = 216) presented to two university hospitals and 14 private veterinary practices in Switzerland during 2016 were retrospectively evaluated. Clinical history, diagnostic work-up and antimicrobial prescription (class, dosage, duration) were assessed. RESULTS A total of 77% (aURTD), 60% (FLUTD) and 96% (abscesses) of the cases received antibiotic therapy; 13-24% received combination or serial therapy. The cats were treated for a median of 7 (abscesses) and 10 days (aURTD, FLUTD). Treatments with potentiated aminopenicillins (40-64%), third generation cephalosporins (25-28%), aminopenicillins (12-24%) and fluoroquinolones (3-13%) were most common. Prescriptions were judged in complete accordance with consensus guidelines in 22% (aURTD), 24% (FLUTD) and 17% (abscesses) of the cases. Antibiotics were prescribed although not indicated in 34% (aURTD), 14% (FLUTD) and 29% (abscesses) of the cases. The presence of lethargy, anorexia or fever in cats with aURTD, and the detection of bacteriuria in cats with FLUTD were significantly associated with antibiotic therapy. Although diagnostic work-up was significantly more common (aURTD: university hospitals, 58%; private practices, 1%; FLUTD: university hospitals, 92%; private practices, 27%) and the use of critically important antibiotics significantly less common at the university hospitals (aURTD, 10%; FLUTD, 14%) compared to private practices (aURTD, 38%; FLUTD, 54%), the frequency of antibiotic treatment was not different between the university hospitals and private practices. CONCLUSIONS Our results indicate that overprescription of antibiotics in cats in Switzerland is common and accordance with guidelines is poor. The study highlights the need to promote antimicrobial stewardship in small animal medicine

    Mitochondria-rough-ER contacts in the liver regulate systemic lipid homeostasis

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    Contacts between organelles create microdomains that play major roles in regulating key intracellular activities and signaling pathways, but whether they also regulate systemic functions remains unknown. Here, we report the ultrastructural organization and dynamics of the inter-organellar contact established by sheets of curved rough endoplasmic reticulum closely wrapped around the mitochondria (wrappER). To elucidate the in vivo function of this contact, mouse liver fractions enriched in wrappER-associated mitochondria are analyzed by transcriptomics, proteomics, and lipidomics. The biochemical signature of the wrappER points to a role in the biogenesis of very-low-density lipoproteins (VLDL). Altering wrappER-mitochondria contacts curtails VLDL secretion and increases hepatic fatty acids, lipid droplets, and neutral lipid content. Conversely, acute liver-specific ablation of Mttp, the most upstream regulator of VLDL biogenesis, recapitulates this hepatic dyslipidemia phenotype and promotes remodeling of the wrappER-mitochondria contact. The discovery that liver wrappER-mitochondria contacts participate in VLDL biology suggests an involvement of inter-organelle contacts in systemic lipid homeostasis.Fil: Anastasia, Irene. Laval University; CanadĂĄ. Brain Research Center; CanadĂĄFil: Ilacqua, NicolĂČ. Laval University; CanadĂĄ. Brain Research Center; CanadĂĄFil: Raimondi, Andrea. San Raffaele Scientific Institute; ItaliaFil: Lemieux, Philippe. Brain Research Center; CanadĂĄFil: Ghandehari-Alavijeh, Rana. Brain Research Center; CanadĂĄFil: Faure, Guilhem. Broad Institute of MIT and Harvard; Estados Unidos. National Center For Biotechnology Information; Estados UnidosFil: Mekhedov, Sergei L.. National Center For Biotechnology Information ; Estados UnidosFil: Williams, Kevin J.. University of California at Los Angeles. School of Medicine; Estados UnidosFil: Caicci, Federico. UniversitĂ  di Padova; ItaliaFil: Valle, Giorgio. UniversitĂ  di Padova; ItaliaFil: Giacomello, Marta. UniversitĂ  di Padova; ItaliaFil: Quiroga, Ariel Dario. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Centro CientĂ­fico TecnolĂłgico Conicet - Rosario. Instituto de FisiologĂ­a Experimental. Universidad Nacional de Rosario. Facultad de Ciencias BioquĂ­micas y FarmacĂ©uticas. Instituto de FisiologĂ­a Experimental; Argentina. University of Alberta; CanadĂĄFil: Lehner, Richard. University of Alberta; CanadĂĄFil: Miksis, Michael J.. Northwestern University; Estados UnidosFil: Toth, Katalin. University of Ottawa; CanadĂĄFil: de Aguiar Vallim, Thomas Q.. University of California at Los Angeles. School of Medicine; Estados UnidosFil: Koonin, Eugene V.. National Center For Biotechnology Information ; Estados UnidosFil: Scorrano, Luca. UniversitĂ  di Padova; ItaliaFil: Pellegrini, Luca. Laval University; Canad

    Effects of drought and meteorological forcing on carbon and water fluxes in Nordic forests during the dry summer of 2018

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    The Nordic region was subjected to severe drought in 2018 with a particularly long-lasting and large soil water deficit in Denmark, Southern Sweden and Estonia. Here, we analyse the impact of the drought on carbon and water fluxes in 11 forest ecosystems of different composition: spruce, pine, mixed and deciduous. We assess the impact of drought on fluxes by estimating the difference (anomaly) between year 2018 and a reference year without drought. Unexpectedly, the evaporation was only slightly reduced during 2018 compared to the reference year at two sites while it increased or was nearly unchanged at all other sites. This occurred under a 40 to 60% reduction in mean surface conductance and the concurrent increase in evaporative demand due to the warm and dry weather. The anomaly in the net ecosystem productivity (NEP) was 93% explained by a multilinear regression with the anomaly in heterotrophic respiration and the relative precipitation deficit as independent variables. Most of the variation (77%) was explained by the heterotrophic component. Six out of 11 forests reduced their annual NEP with more than 50 g C m(-2)yr(-1)during 2018 as compared to the reference year. The NEP anomaly ranged between -389 and +74 g C m(-2)yr(-1)with a median value of -59 g C m(-2)yr(-1). This article is part of the theme issue 'Impacts of the 2018 severe drought and heatwave in Europe: from site to continental scale'.Peer reviewe

    Dolls/puppets as soulmates – biographical traces of dolls/puppets in art, literature, work and performance

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    https://dedo.ub.uni-siegen.deDie vorliegende vierte Ausgabe der Zeitschrift denkste: puppe / just a bit of: doll (de:do), ein multidisziplinĂ€res Online-Journal fĂŒr Mensch-Puppen-Diskurse, greift den Themenschwerpunkt Puppen als Seelenverwandte – biographische Spuren von Puppen in Kunst, Literatur, Werk und Darstellung auf. Es geht um die Frage nach Wirkungen frĂŒher Puppenerfahrungen in der spĂ€teren kĂŒnstlerischen Arbeit und damit nach den möglichen (biographischen) Wurzeln und ZusammenhĂ€ngen von Puppenmotiv und Puppen-Narrativen im kĂŒnstlerisch-literarischen Werk. PuppenbezĂŒge in Werk- und Schaffensprozessen können frĂŒhe Erfahrungen biographischer BrĂŒche und Verletzungen transformieren bzw. sie kĂŒnstlerisch produktiv integrieren, sie können aber auch Ausdruck fĂŒr KontinuitĂ€t und Intensivierung frĂŒher PrĂ€gungen und Vorlieben sein. In den vorliegenden BeitrĂ€gen geht es um puppenbezogene kĂŒnstlerische Ausdrucksformen, die als BeitrĂ€ge hier formal unterschiedlich aufbereitet werden: als wissenschaftsbasierter Text, Selbstbericht, Miszelle, Rezension, Interview und: Kunstwerk. Untersucht und thematisiert werden Puppen-Sammlungen, die Herstellung besonderer Puppen, literarische Puppentexte, Inszenierungen und Bilder. Außerdem wurden weitere BeitrĂ€ge einbezogen, die Puppen als Varianten „kĂŒnstlicher Menschen“ in unterschiedlichsten ThemenbezĂŒgen behandeln. In vielen BeitrĂ€gen deutet sich an, dass die AffinitĂ€t zum „PhĂ€nomen Puppe“ in seinen verschiedenen kĂŒnstlerischen Umsetzungsformen auf biographisch geprĂ€gte Spuren verweist: als Ausdrucks- und Darstellungsmittel steht die Puppe somit auch fĂŒr etwas Besonderes der Menschen, die sich kĂŒnstlerisch auf sie beziehen und mit ihr interagieren und „spielen“.This fourth issue of denkste: puppe / just a bit of: doll (de:do), a multidisciplinary online journal for human-doll discourses, takes up the thematic focus on dolls/puppets as soulmates – biographical traces of dolls/puppets in art, literature, work and performance. It is about the impact of early doll experiences in later artistic work and thus about the possible (biographical) roots and connections of doll motifs and doll narratives in artistic-literary work. Doll/puppet references in work and creative processes can transform early experiences of biographical breaks and harm or integrate them in an artistically productive way, but they can also be an expression of continuity and intensification of early experience and preferences. The present contributions deal with doll/puppet-related artistic forms of expression, which are formally presented in different ways: as science-based text, self-report, miscellaneous, review, interview and: work of art. Doll/puppet collections, the making of particular puppets, literary puppet texts, performances and images are examined and addressed. In addition, further contributions were included, which deal with dolls as variants of "artificial humans" in the most diverse thematic contexts. Most of the contributions indicate that the affinity to the “phenomenon of the doll” in its various artistic forms of realization refers to biographically shaped traces: as a means of expression and representation the doll thus also stands for something special about the human beings who refer to it artistically and interact and "play" with it

    The fingerprint of the summer 2018 drought in Europe on ground-based atmospheric CO2 measurements

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    During the summer of 2018, a widespread drought developed over Northern and Central Europe. The increase in temperature and the reduction of soil moisture have influenced carbon dioxide (CO2) exchange between the atmosphere and terrestrial ecosystems in various ways, such as a reduction of photosynthesis, changes in ecosystem respiration, or allowing more frequent fires. In this study, we characterize the resulting perturbation of the atmospheric CO2 seasonal cycles. 2018 has a good coverage of European regions affected by drought, allowing the investigation of how ecosystem flux anomalies impacted spatial CO2 gradients between stations. This density of stations is unprecedented compared to previous drought events in 2003 and 2015, particularly thanks to the deployment of the Integrated Carbon Observation System (ICOS) network of atmospheric greenhouse gas monitoring stations in recent years. Seasonal CO2 cycles from 48 European stations were available for 2017 and 2018.The UK sites were funded by the UK Department of Business, Energy and Industrial Strategy (formerly the Department of Energy and Climate Change) through contracts TRN1028/06/2015 and TRN1537/06/2018. The stations at the ClimaDat Network in Spain have received funding from the ‘la Caixa’ Foundation, under agreement 2010-002624

    Observation of gravitational waves from the coalescence of a 2.5−4.5 M⊙ compact object and a neutron star

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