1,172 research outputs found

    HÄllbart vÀxtskydd. Analys av olika strategier för att minska riskerna med kemiska vÀxtskyddsmedel

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    Risker som Ă€r förknippade med kemiska vĂ€xtskyddsmedel kan sammanfattas i fem omrĂ„den: risker för anvĂ€ndare, risker för rester i livsmedel samt i yt- och grundvatten och risker för natursystemet (t.ex. förlorad biodiversitet). De viktigaste fördelarna med vĂ€xtskyddsmedel Ă€r att de bidrar till skördeökningar och att de förbĂ€ttrar möjligheten till stabila skördenivĂ„er, oavsett Ă„rsmĂ„n. Det finns olika strategier för att hantera vĂ€xtskyddet i dagens jordbruk och beroende pĂ„ vilken strategi som vĂ€ljs förĂ€ndras riskerna som Ă€r förknippade med anvĂ€ndningen av vĂ€xtskyddsmedel. Syftet med MAT 21-projektet HĂ„llbart VĂ€xtskydd har varit att analysera den miljömĂ€ssiga hĂ„llbarheten i olika vĂ€xtskyddsstrategier med hjĂ€lp av konkreta exempel. Ambitionen Ă€r att ge vĂ€gledning om genomförandet av politiska miljömĂ„l, tolkning av miljöanalyser och utveckling av kvalitets- och miljöledningssystem i livsmedelsföretag. I projektet har en varierad vĂ€xtföljd setts som en viktig förebyggande Ă„tgĂ€rd för att minska riskerna med vĂ€xtskyddsmedel. En diversifierad vĂ€xtföljd bidrar till att reducera vissa typer av ogrĂ€s och till att minska trycket av mĂ„nga svampsjukdomar. Mekanisk ogrĂ€sreglering ger tillsammans med förebyggande Ă„tgĂ€rder möjligheter att minska anvĂ€ndningen av vĂ€xtskyddsmedel. Exempel pĂ„ tekniska lösningar som kan minska riskerna Ă€r bandsprutning i kombination med radrensning eller ny bredsprutningsteknik med lufttillsats vilket reducerar vindavdriften vid en applikation med vĂ€xtskyddsmedel. För att analysera riskerna som Ă€r förknippade med vĂ€xtskyddsmedel anvĂ€ndes modellen PRI-Farm som Ă€r en riskindikatormodell utvecklad av Kemikalieinspektionen. I modellen poĂ€ngsĂ€tts faktorer för fara och exponering vid applikation av vĂ€xtskyddsmedel. Farofaktorerna utrycker belastningen av de inneboende egenskaperna hos preparatens aktiva substans som persistens, bioackumulering och rörlighet. Exponeringsfaktorerna beaktar applikationsmetod, anvĂ€nd dos, markegenskaper och spruttidpunkt. Resultaten vĂ€gs samman i en poĂ€ngsumma (ett miljöriskindex), dĂ€r risk för transport till yt- och grundvatten vĂ€ger tungt. Även ett hĂ€lsoriskindex kan berĂ€knas, vilket inte gjorts i denna studie. Modellen kan inte anvĂ€ndas för att kvantifiera risker utan Ă€r i stĂ€llet ett verktyg för att kunna göra jĂ€mförande bedömningar mellan olika strategier för vĂ€xtskyddsinsatser, identifiera problemanvĂ€ndningar eller för att visa pĂ„ risktrender över tiden. För att analysera andra miljöeffekter (t.ex. klimatpĂ„verkan och energianvĂ€ndning) anvĂ€ndes metodiken för livscykelanalys (LCA). Detta Ă€r en metod som anvĂ€nds för att göra miljöbedömningar av produkter och tjĂ€nster. Man genomför berĂ€kningar för produktens potentiella bidrag till olika miljöeffekter, sĂ„som vĂ€xthuseffekt och försurning, och man summerar Ă€ven den förbrukning av viktiga resurser som produkten givit upphov till. Tanken Ă€r att dessa berĂ€kningar skall kunna ge information som kan leda till att man kan minska miljöpĂ„verkan frĂ„n en viss produkt pĂ„ ett effektivt sĂ€tt. Resultaten kan ocksĂ„ ge vĂ€gledning vid val mellan produkter som Ă€r likvĂ€rdiga i övrigt. I fallstudien av den allsidiga vĂ€xtodlingsgĂ„rden jĂ€mfördes ocksĂ„ nulĂ€get med ett scenario dĂ€r gĂ„rden lades om till ekologisk produktion. I detta alternativ anvĂ€ndes inga kemiska vĂ€xtskyddsmedel. OmlĂ€ggningen till ekologisk produktion pĂ„verkade Ă€ven andra miljöeffekter, förutom riskerna med vĂ€xtskyddsmedel. En negativ effekt av det ekologiska scenariot var att grödan kepalök fick utgĂ„ p.g.a. att risken bedömdes som för stor för ett stort skördebortfall utan tillgĂ„ng pĂ„ fungicider. PĂ„ grund av en lĂ€gre skördenivĂ„ i ekologisk produktion behövdes en betydligt större yta för att producera en given mĂ€ngd livsmedel. I en ekonomisk analys jĂ€mfördes nulĂ€get pĂ„ den allsidiga vĂ€xtodlingsgĂ„rden med ett ekologiskt scenario. Resultatet var likvĂ€rdigt för de tvĂ„ alternativen. För att ekologisk odling skall vara en ekonomiskt lyckad satsning pĂ„ gĂ„rdar i intensiva slĂ€ttbygder med odling av specialgrödor Ă€r det, med dagens nivĂ„ pĂ„ miljöstödet för ekologisk produktion, helt nödvĂ€ndigt att det finns ett bra merpris för produkterna. I en fallstudie av en allsidig vĂ€xtodlingsgĂ„rd jĂ€mfördes nulĂ€get med ett scenario dĂ€r olika strategier testades som minskade riskerna med vĂ€xtskyddsmedel utan att skördenivĂ„n Ă€ndrades nĂ€mnvĂ€rt. Detta scenario (kallat BĂ€sta Möjliga Teknik) innebar anvĂ€ndning av mekanisk och/eller termisk behandling som alternativ till konventionell bekĂ€mpning i vissa grödor samt medvetna val av vĂ€xtskyddsmedel som hade mindre dĂ„liga miljöegenskaper. Fallstudien visade pĂ„ flera olika möjligheter till att reducera riskerna i konventionell drift. Eftersom gĂ„rden i studien hade mĂ„nga radodlade specialgrödor bedömdes bandsprutning kombinerat med radrensning vara en intressant förbĂ€ttring. Att vĂ€sentligt reducera anvĂ€ndningen av fungicider i potatis och lök utan att Ă€ventyra skördenivĂ„n bedömdes som mycket svĂ„rt i konventionell drift, Ă€ven med bĂ€sta odlingsteknik. I fallstudien av den allsidiga vĂ€xtodlingsgĂ„rden jĂ€mfördes ocksĂ„ nulĂ€get med ett scenario dĂ€r gĂ„rden lades om till ekologisk produktion. Detta alternativ minskar riskerna med vĂ€xtskydds-medel radikalt men pĂ„verkar Ă€ven andra miljöeffekter. För mĂ„nga grödor minskade energianvĂ€ndning, liksom utslĂ€pp av vĂ€xthusgaser vid en övergĂ„ng till ekologisk odling. En negativ effekt av det ekologiska scenariot var att grödan kepalök fick utgĂ„ p g a att risken bedömdes som för stor för ett betydande skördebortfall utan tillgĂ„ng till fungicider. Ur miljö- och resurssynpunkt var den mest negativa effekten att det ekologiska scenariot krĂ€vde mycket större yta för att producera en given mĂ€ngd livsmedel. I en ekonomisk analys jĂ€mfördes nulĂ€get pĂ„ den allsidiga vĂ€xtodlingsgĂ„rden med ett ekologiskt scenario. Resultatet var likvĂ€rdigt för de tvĂ„ alternativen. För att ekologisk odling skall vara en ekonomiskt lyckad satsning pĂ„ gĂ„rdar i intensiva slĂ€ttbygder Ă€r det helt nödvĂ€ndigt att det finns ett bra merpris för produkterna. Studien visar att det finns flera olika strategier för att minska riskerna med anvĂ€ndningen av vĂ€xtskyddsmedel. En varierad vĂ€xtföljd Ă€r en grundlĂ€ggande förutsĂ€ttning i alla odlingssystem och inom detta omrĂ„de finns det mycket gammal kunskap som behöver vĂ€ckas till liv. Miljöanalyserna visar ocksĂ„ att mĂ„nga tekniska lösningar, som leder till minskat behov av vĂ€xtskyddsmedel, kan tillĂ€mpas utan att andra miljöeffekter pĂ„verkas nĂ€mnvĂ€rt. Att vĂ€lja bort vĂ€xtskyddsmedel som har mindre goda miljöeffekter Ă€r en strategi som förefaller ha stor potential för att minska riskerna. PRI-Farm kan bli ett viktigt beslutsstöd i lantbrukets arbete för bĂ€ttre produktval och sĂ€krare vĂ€xtskydd. Ekologisk produktion har goda förutsĂ€ttningar att bli en viktig strategi för minskade risker i de utökade vattenskyddsomrĂ„den som kommunerna nyligen har beslutat om. För att denna strategi skall bli lyckosam krĂ€vs att marknaden fortsĂ€tter att öka för ekologiska produkter i Sverige, sĂ„ att produkternas merpris tillsammans med samhĂ€llets stöd via miljöersĂ€ttningsprogram fortsĂ€tter att betala merkostnaden för denna produktionsform

    Comparison between interstitial laser thermotherapy and excision of an adenocarcinoma transplanted into rat liver.

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    The aim of this study was to compare interstitial laser thermotherapy with excision of a liver tumour. A dimethylhydrazine-induced adenocarcinoma was transplanted (implanted if not stated otherwise) into the left lateral lobe of the rat liver, and treatment was performed 8 days later. In the main experiment, rats were treated with resection of the tumour-bearing lobe or underwent interstitial laser thermotherapy, which was performed at a steady-state temperature of 46 degrees C for 30 min, 3 mm from the tumour margin. The incidence and extent of intraperitoneal spread was smaller after laser thermotherapy than after resection of the tumour-bearing lobe, with no difference in local control. Metastatic spread after resection of the median liver lobe was similar to that observed after sham procedures for thermotherapy or resection, suggesting that the advantage of thermotherapy was not due to a difference in surgical trauma. Additional studies showed that laser thermotherapy reduced intraperitoneal spread when treatment was suboptimal or in a tumour inoculation model and suggested that immunological mechanisms might be involved. It is concluded that interstitial laser thermotherapy reduces spread of liver tumour compared with resection

    Precipitation of Mn Oxides in Quaternary microbially induced sedimentary structures (MISS), Cape Vani Paleo-Hydrothermal Vent Field, Milos, Greece

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    Understanding microbial mediation in sediment-hosted Mn deposition has gained importance in low-temperature ore genesis research. Here we report Mn oxide ores dominated by todorokite, vernadite, hollandite, and manjiroite, which cement Quaternary microbially induced sedimentary structures (MISS) developed along bedding planes of shallow-marine to tidal-flat volcaniclastic sandstones/sandy tuffs, Cape Vani paleo-hydrothermal vent field, Milos, Greece. This work aims to decipher the link between biological Mn oxide formation, low-T hydrothermalism, and, growth and preservation of Mn-bearing MISS (MnMISS). Geobiological processes, identified by microtexture petrography, scanning and transmission electron microscopy, lipid biomarkers, bulk- and lipid-specific ή13Corganic composition, and field data, and, low-temperature hydrothermal venting of aqueous Mn2+ in sunlit shallow waters, cooperatively enabled microbially-mediated Mn (II) oxidation and biomineralization. The MnMISS biomarker content and ή13Corg signatures strongly resemble those of modern Mn-rich hydrothermal sediments, Milos coast. Biogenic and syngenetic Mn oxide precipitation established by electron paramagnetic resonance (EPR) spectroscopy and petrography, combined with hydrothermal fluid flow-induced pre-burial curing/diagenesis, may account for today’s crystalline Mn oxide resource. Our data suggests that MISS are not unique to cyanobacteria mats. Furthermore, microbial mats inhabited by aerobic methanotrophs may have contributed significantly to the formation of the MnMISS, thus widening the spectrum of environments responsible for marine Mn biometallogenesi

    Arsenic and high affinity phosphate uptake gene distribution in shallow submarine hydrothermal sediments

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    The toxicity of arsenic (As) towards life on Earth is apparent in the dense distribution of genes associated with As detoxification across the tree of life. The ability to defend against As is particularly vital for survival in As-rich shallow submarine hydrothermal ecosystems along the Hellenic Volcanic Arc (HVA), where life is exposed to hydrothermal fluids containing up to 3000 times more As than present in seawater. We propose that the removal of dissolved As and phosphorus (P) by sulfide and Fe(III)(oxyhydr)oxide minerals during sediment-seawater interaction, produces nutrient-deficient porewaters containing < 2.0 ppb P. The porewater arsenite-As(III) to arsenate-As(V) ratios, combined with sulfide concentration in the sediment and/or porewater, suggest a hydrothermally-induced seafloor redox gradient. This gradient overlaps with changing high affinity phosphate uptake gene abundance. High affinity phosphate uptake and As cycling genes are depleted in the sulfide-rich settings, relative to the more oxidizing habitats where mainly Fe(III)(oxyhydr)oxides are precipitated. In addition, a habitat-wide low As-respiring and As-oxidizing gene content relative to As resistance gene richness, suggests that As detoxification is prioritized over metabolic As cycling in the sediments. Collectively, the data point to redox control on Fe and S mineralization as a decisive factor in the regulation of high affinity phosphate uptake and As cycling gene content in shallow submarine hydrothermal ecosystems along the HVA

    A New Luminescence Assay for Autoantibodies to Mammalian Cell–Prepared Insulinoma-Associated Protein 2

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    OBJECTIVE—Insulinoma-associated protein 2 (IA-2) is a major autoantigen in type 1 diabetes, and IA-2 autoantibodies are routinely detected by a liquid-phase radioimmunoprecipitation assay. The present experiments were initiated to develop a new assay that does not require the use of radioisotopes or autoantigens prepared in bacteria or by in vitro transcription/translation

    Frizzled 7 and PIP₂ binding by syntenin PDZ₂ domain supports Frizzled 7 trafficking and signalling

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    PDZ domain-containing proteins work as intracellular scaffolds to control spatio-temporal aspects of cell signalling. This function is supported by the ability of their PDZ domains to bind other proteins such as receptors, but also phosphoinositide lipids important for membrane trafficking. Here we report a crystal structure of the syntenin PDZ tandem in complex with the carboxy-terminal fragment of Frizzled 7 and phosphatidylinositol 4,5-bisphosphate (PIP₂). The crystal structure reveals a tripartite interaction formed via the second PDZ domain of syntenin. Biophysical and biochemical experiments establish co-operative binding of the tripartite complex and identify residues crucial for membrane PIP₂-specific recognition. Experiments with cells support the importance of the syntenin–PIP₂ interaction for plasma membrane targeting of Frizzled 7 and c-jun phosphorylation. This study contributes to our understanding of the biology of PDZ proteins as key players in membrane compartmentalization and dynamics

    Coupling to short linear motifs creates versatile PME-1 activities in PP2A holoenzyme demethylation and inhibition

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    Protein phosphatase 2A (PP2A) holoenzymes target broad substrates by recognizing short motifs via regulatory subunits. PP2A methylesterase 1 (PME-1) is a cancer-promoting enzyme and undergoes methylesterase activation upon binding to the PP2A core enzyme. Here, we showed that PME-1 readily demethylates different families of PP2A holoenzymes and blocks substrate recognition in vitro. The high-resolution cryoelectron microscopy structure of a PP2A-B56 holoenzyme–PME-1 complex reveals that PME-1 disordered regions, including a substrate-mimicking motif, tether to the B56 regulatory subunit at remote sites. They occupy the holoenzyme substrate-binding groove and allow large structural shifts in both holoenzyme and PME-1 to enable multipartite contacts at structured cores to activate the methylesterase. B56 interface mutations selectively block PME-1 activity toward PP2A-B56 holoenzymes and affect the methylation of a fraction of total cellular PP2A. The B56 interface mutations allow us to uncover B56-specific PME-1 functions in p53 signaling. Our studies reveal multiple mechanisms of PME-1 in suppressing holoenzyme functions and versatile PME-1 activities derived from coupling substrate-mimicking motifs to dynamic structured cores

    Anthropogenic and climatic impacts on a coastal environment in the Baltic Sea over the last 1000 years

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    Coastal environments have experienced large ecological changes as a result of human activities over the last 100-200 years. To understand the severity and potential consequences of such changes, paleoenvironmental records provide important contextual information. The Baltic Sea coastal zone is naturally a vulnerable system and subject to significant human-induced impacts. To put the recent environmental degradation in the Baltic coastal zone into a long-term perspective, and to assess the natural and anthropogenic drivers of environmental change, we present sedimentary records covering the last 1000 years obtained from a coastal inlet (Gasfjarden) and a nearby lake (Lake Storsjon) in Sweden. We investigate the links between a pollen-based land cover reconstruction from Lake Storsjon and paleoenvironmental variables from Gasfjarden itself, including diatom assemblages, organic carbon (C) and nitrogen (N) contents, stable C and N isotopic ratios, and biogenic silica contents. The Lake Storsjon record shows that regional land use was characterized by small-scale agricultural activity between 900 and 1400 CE, which slightly intensified between 1400 and 1800 CE. Substantial expansion of cropland was observed between 1800 and 1950 CE, before afforestation between 1950 and 2010 CE. From the Gasfjarden record, prior to 1800 CE, relatively minor changes in the diatom and geochemical proxies were found. The onset of cultural eutrophication in Gasfjarden can be traced to the 1800s and intensified land use is identified as the main driver. Anthropogenic activities in the 20th century have caused unprecedented ecosystem changes in the coastal inlet, as reflected in the diatom composition and geochemical proxies. (c) 2018 Elsevier Ltd. All rights reserved.Peer reviewe

    The breakdown of the municipality as caring platform: lessons for co-design and co-learning in the age of platform capitalism

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    If municipalities were the caring platforms of the 19-20th century sharing economy, how does care manifest in civic structures of the current period? We consider how platforms - from the local initiatives of communities transforming neighbourhoods, to the city, in the form of the local authority - are involved, trusted and/or relied on in the design of shared services and amenities for the public good. We use contrasting cases of interaction between local government and civil society organisations in Sweden and the UK to explore trends in public service provision. We look at how care can manifest between state and citizens and at the roles that co-design and co-learning play in developing contextually sensitive opportunities for caring platforms. In this way, we seek to learn from platforms in transition about the importance of co-learning in political and structural contexts and make recommendations for the co-design of (digital) platforms to care with and for civil society

    The Hamburg/ESO R-process Enhanced Star survey (HERES). V. Detailed abundance analysis of the r-process enhanced star HE 2327-5642

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    We report on a detailed abundance analysis of the strongly r-process enhanced giant star, HE 2327-5642 ([Fe/H] = -2.78, [r/Fe] = +0.99). Determination of stellar parameters and element abundances was based on analysis of high-quality VLT/UVES spectra. The surface gravity was calculated from the NLTE ionization balance between Fe I and Fe II, and Ca I and Ca II. Accurate abundances for a total of 40 elements and for 23 neutron-capture elements beyond Sr and up to Th were determined. The heavy element abundance pattern of HE 2327-5642 is in excellent agreement with those previously derived for other strongly r-process enhanced stars. Elements in the range from Ba to Hf match the scaled Solar r-process pattern very well. No firm conclusion can be drawn with respect to a relationship between the fisrt neutron-capture peak elements, Sr to Pd, in HE 2327-5642 and the Solar r-process, due to the uncertainty of the latter. A clear distinction in Sr/Eu abundance ratios was found between the halo stars with different europium enhancement. The strongly r-process enhanced stars reveal a low Sr/Eu abundance ratio at [Sr/Eu] = -0.92+-0.13, while the stars with 0 < [Eu/Fe] < 1 and [Eu/Fe] < 0 have 0.36 dex and 0.93 dex larger Sr/Eu values, respectively. Radioactive dating for HE 2327-5642 with the observed thorium and rare-earth element abundance pairs results in an average age of 13.3 Gyr, when based on the high-entropy wind calculations, and 5.9 Gyr, when using the Solar r-residuals. HE 2327-5642 is suspected to be radial-velocity variable based on our high-resolution spectra, covering ~4.3 years.Comment: 16 pages, 12 figures, accepted to A&
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