Does conversion to conservation tillage really increase soil organic carbon stocks in organic arable farming?

Aggravation of weather extremes increases awareness of climate change consequences. Mitigation options are in demand which aim to reduce the atmospheric concentration of greenhouse gases. Amongst others, conversion from ploughing to conservation tillage is argued to increase soil organic carbon (SOC) stocks. Yet, main findings of reviews and meta-analyses comparing SOC stocks between tillage systems show different results: from a significant increase of SOC stocks to the question if there is any effect at all. Reasons are a sampling bias as in many campaigns only topsoil layers are assessed and horizons thickness is not considered adequately, different methods for SOC and bulk density determination, and the comparison of SOC stocks based on equivalent soil masses instead of equal sampling depths. In order to address these limitations, we initiated the SOCORT consortium (Soil Organic Carbon in Organic Reduced Tillage) – an international network of nine agronomical long-term trials. All trials represent common mixed organic farming systems of the respective region with organic fertilisation and crop rotations including leys. Climatic conditions are similar, but age and soil texture vary (7 to 21 years and sandy to clayey soils). A common sampling campaign was consequently elaborated to answer the question if the combination of conservation tillage and organic farming can really increase SOC stocks. Undisturbed soil cores were taken with driving hammer probes (8 cm in diameter) to a maximum depth of 100 cm. Each core was divided in the increments 0-30, 30-50, 50-70, 70-100 cm. The topsoil layer (0-30 cm) was further divided into the different tillage depths of the respective trial. All samples were analysed in the same laboratory for bulk density, organic carbon content, pH and texture. We compiled the yields for each trial to assess carbon inputs. The SOCORT consortium in combination with the common sampling campaign will entangle the driving factors of carbon sequestration through reduced tillage and add important knowledge on carbon dynamics in agro-ecosystems

Heparan Sulfate Proteoglycans Mediate the Angiogenic Activity of the Vascular Endothelial Growth Factor Receptor-2 Agonist Gremlin.

OBJECTIVE: Heparan sulfate proteoglycans (HSPGs) modulate the interaction of proangiogenic heparin-binding vascular endothelial growth factors (VEGFs) with signaling VEGF receptor-2 (VEGFR2) and neuropilin coreceptors in endothelial cells (ECs). The bone morphogenic protein antagonist gremlin is a proangiogenic ligand of VEGFR2, distinct from canonical VEGFs. Here we investigated the role of HSPGs in VEGFR2 interaction, signaling, and proangiogenic capacity of gremlin in ECs. METHODS AND RESULTS: Surface plasmon resonance demonstrated that gremlin binds heparin and heparan sulfate, but not other glycosaminoglycans, via N-, 2-O, and 6-O-sulfated groups of the polysaccharide. Accordingly, gremlin binds HSPGs of the EC surface and extracellular matrix. Gremlin/HSPG interaction is prevented by free heparin and heparan sulfate digestion or undersulfation following EC treatment with heparinase II or sodium chlorate. However, at variance with canonical heparin-binding VEGFs, gremlin does not interact with neuropilin-1 coreceptor. On the other hand, HSPGs mediate VEGFR2 engagement and autophosphorylation, extracellular signaling-regulated kinase(1/2) and p38 mitogen-activated protein kinase activation, and consequent proangiogenic responses of ECs to gremlin. On this basis, we evaluated the gremlin-antagonist activity of a panel of chemically sulfated derivatives of the Escherichia coli K5 polysaccharide. The results demonstrate that the highly N,O-sulfated derivative K5-N,OS(H) binds gremlin with high potency, thus inhibiting VEGFR2 interaction and angiogenic activity in vitro and in vivo. CONCLUSIONS: HSPGs act as functional gremlin coreceptors in ECs, affecting its productive interaction with VEGFR2 and angiogenic activity. This has allowed the identification of the biotechnological K5-N,OS(H) as a novel angiostatic gremlin antagonist

Desempenho de clones de Eucalyptus no oeste do Estado do Paraná.

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Caracterização da qualidade comercial da soja colhida na safra 2011-2012 no Estado do Paraná e Mato Grosso do Sul.

A soja tem se consolidado como um dos principais produtos de exportação do Brasil e uma das principais commodities do mundo. A produção brasileira atingiu 75 milhões de toneladas na safra 2010/11. A qualidade da soja colhida e comercializada é fundamental para garantir mercados interno e externo, por isto a necessidade de se conhecer os detalhes que afetam a qualidade da soja colhida a cada safra é vital. O objetivo deste trabalho foi de caracterizar a qualidade comercial da soja colhida na safra 2011/2012, no estado do Paraná e do Mato Grosso do Sul, considerando a classificação comercial, o teor de óleo e proteína, e a presença de fungos contaminantes. Amostras de soja colhidas nestas regiões foram coletadas de diversos pontos representados por coleta direto do produtor no momento da colheita, bem como na recepção de unidades armazenadoras de grãos. Após acondicionadas, as mesmas foram encaminhadas a Embrapa Soja, onde foi realizada a classificação comercial, determinação do teor de óleo, de proteína, e da sanidade pela presença de fungos contaminantes. Os resultados mostraram que houve amostras com teor de impurezas, grãos esverdeados e grãos avariados acima dos limites tolerados pela legislação brasileira. O teor de óleo e proteína não sofreram alterações significativas nestas amostras em função dos defeitos de campo. A presença de fungos importantes como Aspergilus sp e Fusarium sp encontrados nas amostras, demonstraram um grau de contaminação da soja a campo

Molecular Interaction Studies of HIV-1 Matrix Protein p17 and Heparin: IDENTIFICATION OF THE HEPARIN-BINDING MOTIF OF p17 AS A TARGET FOR THE DEVELOPMENT OF MULTITARGET ANTAGONISTS

Once released by HIV cells, p17 binds heparan sulfate proteoglycans (HSPGs) and CXCR1 on leukocytes causing their dysfunction. By exploiting an approach integrating computational modeling, site-directed mutagenesis of p17, chemical desulfation of heparin, and surface plasmon resonance, we characterized the interaction of p17 with heparin, a HSPG structural analog, and CXCR1. p17 binds to heparin with an affinity (Kd 190 nM) that is similar to those of other heparin-binding viral proteins. Two stretches of basic amino acids (basic motifs) are present in p17 N and C termini. Neutralization (Arg3Ala substitution) of the N-terminal, but not of the C-terminal basic motif, causes the loss of p17 heparin-binding capacity. The N-terminal heparin-binding motif of p17 partially overlaps the CXCR1-binding domain. Accordingly, its neutralization prevents also p17 binding to the chemochine receptor. Competition experiments demonstrated that free heparin and heparan sulfate (HS), but not selectively 2-O-, 6-O-, and N-O desulfated heparins, prevent p17 binding to substrate-immobilized heparin, indicating that the sulfate groups of the glycosaminoglycan mediate p17 interaction. Evaluation of the p17 antagonist activity of a panel of biotechnological heparins derived by chemical sulfation of the Escherichia coli K5 polysaccharide revealed that the highlyN,O-sulfated derivative prevents the binding of p17 to both heparin and CXCR1, thus inhibiting p17-driven chemotactic migration of human monocytes with an efficiency that is higher than those of heparin and HS. Here, we characterized at a molecular level the interaction of p17 with its cellular receptors, laying the basis for the development of heparin-mimicking p17 antagonists

Placing the law: The socio‐spatial impact of legal norms beyond mere compliance

This paper explores the complex ways in which a legal norm can influence a socio-spatial context. More precisely, the paper aims to contribute to the theoretical investigation of the nexus between law and space in the field of legal geography by proposing an analytical framework for the study of the spatial operativity of law beyond compliance. To do so, this work relies on the concepts of nomotropism (namely, "acting in light of the rule") and effectiveness-as-operativity. They imply that (1) any legal norm that has a causal relation with an action can be deemed effective regardless of whether such action conforms with or transgresses such norm, and (2) the impact of a norm is not confined to mere compliance. The paper then articulates the analytical framework derived by these theoretical insights with reference to different kinds of norms (law in actu and law in intellectu; law in books and law in practice). The relevance of the resulting theoretical structure for the investigation of complex socio-spatial phenomena is finally exemplified through the analysis of a conflictual process for the establishment of a Muslim place of worship in Italy