HOPF BIFURCATION ANALYSIS FOR SIMPLE THIRD-ORDER QUADRATIC SYSTEMS

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A chlorophyll-deficient, highly reflective soybean mutant: radiative forcing and yield gaps

Sunlight absorbed at the Earth’s surface is re-emitted as longwave radiation. Increasing atmospheric concentrations of CO2 and other greenhouse gases trap an increasing fraction of such heat, leading to global climate change. Here we show that when a chlorophyll (Chl)-deficient soybean mutant is grown in the field, the fraction of solar-irradiance which is reflected, rather than absorbed, is consistently higher than in commercial varieties. But, while the effect on radiative forcing during the crop cycle at the scale of the individual experimental plot was found to be large (−4.1± 0.6 W m−2 ), global substitution of the current varieties with this genotype would cause a small increase in global surface albedo, resulting in a global shortwave radiative forcing of −0.003 W m−2 , corresponding to 4.4 Gt CO2eq. At present, this offsetting effect would come at the expense of reductions to yields, probably associated with different dynamic of photosynthetic response in the Chl-deficient mutant. The idea of reducing surface-driven radiative forcing by means of Chl-deficient crops therefore requires that novel high-yielding and high-albedo crops are made available soon.publishedVersio

Fate of soil organic carbon and polycyclic aromatic hydrocarbons in a vineyard soil treated with biochar

The effect of biochar addition on the levels of black carbon (BC) and polcyclic aromatic hydrocarbons (PAHs) in a vineyard soil in central Italy was investigated within a two year period. Hydropyrolysis (HyPy) was used to determine the contents of BC (BCHyPy) in the amended and control soils while the hydrocarbon composition of the semi-labile (non-BCHyPy) fraction released by HyPy was determined by gas chromatography-mass spectrometry, together with the solvent-extractable PAHs. The concentrations of these three polycyclic aromatic carbon reservoirs, changed and impacted differently on the soil organic carbon over the period of the trial. The addition of biochar (33 ton dry biochar ha-1) gave rise to a sharp increase in soil organic carbon which could be accounted for by an increase of BCHyPy. Over time, the concentration of BCHyPy decreased significantly from 36 to 23 mg g-1, and as a carbon percentage from 79% to 61%. No clear time trends were observed for the non-BCHyPy PAHs varying from 39 to 34 µg g-1 in treated soils, not significantly different from control soils. However, the concentrations of extractable PAHs increased markedly in the amended soils, and decreased with time from 153 to 78 ng g-1 remaining always higher than those in untreated soil. The extent of the BCHyPy loss was more compatible with physical rather than chemical processes

Immunoglobulin heavy-chain fluorescence in situ hybridization-chromogenic in situhybridization DNA probe split signal in the clonality assessment oflymphoproliferative processes on cytological samples.

BACKGROUND: The human immunoglobulin heavy-chain (IGH) locus at chromosome 14q32 is frequently involved in different translocations of non-Hodgkin lymphoma (NHL), and the detection of any breakage involving the IGH locus should identify a B-cell NHL. The split-signal IGH fluorescence in situ hybridization-chromogenic in situ hybridization (FISH-CISH) DNA probe is a mixture of 2 fluorochrome-labeled DNAs: a green one that binds the telomeric segment and a red one that binds the centromeric segment, both on the IGH breakpoint. In the current study, the authors tested the capability of the IGH FISH-CISH DNA probe to detect IGH translocations and diagnose B-cell lymphoproliferative processes on cytological samples. METHODS: Fifty cytological specimens from cases of lymphoproliferative processes were tested using the split-signal IGH FISH-CISH DNA probe and the results were compared with light-chain assessment by flow cytometry AQ2 (FC), IGH status was tested by polymerase chain reaction (PCR), and clinicohistological data. RESULTS: The signal score produced comparable results on FISH and CISH analysis and detected 29 positive, 15 negative, and 6 inadequate cases; there were 29 true-positive cases (66%), 9 true-negative cases (20%), 6 false-negative cases (14%), and no false-positive cases (0%). Comparing the sensitivity of the IGH FISH-CISH DNA split probe with FC and PCR, the highest sensitivity was obtained by FC, followed by FISH-CISH and PCR. CONCLUSIONS: The split-signal IGH FISH-CISH DNA probe is effective in detecting any translocation involving the IGH locus. This probe can be used on different samples from different B-cell lymphoproliferative processes, although it is not useful for classifying specific entities

Biochar standardization and legislation harmonization

It is a relatively new concept to use biochar as soil amendment and for climate change mitigation. For this reason, the national and supranational legislation in the EU is not yet adequately prepared to regulate both the production and the application of biochar. Driven by this “regulatory gap”, voluntary biochar quality standards have been formed in Europe with the European Biochar Certificate, in the UK with the Biochar Quality Mandate and in the USA with the IBI Standard which is intended to be used internationally. In parallel to this, biochar producers and biochar users in a number of EU countries were partly successful in fitting the new biochar product into the existing national legislation for fertilisers, soil improvers and composts. The intended revision of the EC Regulation 2003/2003 on fertilisers offers the opportunity to regulate the use of biochar at the EU level. This publication summarizes the efforts on biochar standardization which have been carried out by voluntary products standards and illustrates existing legislation in EU member states, which apply to the production and use of biochar. It describes existing and planned EU regulations, which impact biochar applications and it develops recommendations on the harmonization of biochar legislation in the EU.  First published online: 24 Jan 201

Diet-induced early-stage atherosclerosis in baboons: lipoproteins, atherogenesis, and arterial compliance

Background The purpose of this study was to determine if dietary manipulation can reliably induce early-stage atherosclerosis and clinically relevant changes in vascular function in an established, well-characterized nonhuman primate model. Methods We fed 112 baboons a high cholesterol, high fat challenge diet for two years. We assayed circulating biomarkers of cardiovascular disease (CVD) risk, at 0, 7, and 104 weeks into the challenge; assessed arterial compliance noninvasively at 104 weeks; and measured atherosclerotic lesions in three major arteries at necropsy. Results We observed evidence of atherosclerosis in all but one baboon fed the two-year challenge diet. CVD risk biomarkers, the prevalence, size, and complexity of arterial lesions, plus consequent arterial stiffness, were increased in comparison to dietary control animals. Conclusions Feeding baboons a high cholesterol, high fat diet for two years reliably induces atherosclerosis, with risk factor profiles, arterial lesions, and changes in vascular function also seen in humans

Sustainability, certification, and regulation of biochar

Biochar has a relatively long half-life in soil and can fundamentally alter soil properties, processes, and ecosystem services. The prospect of global-scale biochar application to soils highlights the importance of a sophisticated and rigorous certification procedure. The objective of this work was to discuss the concept of integrating biochar properties with environmental and socioeconomic factors, in a sustainable biochar certification procedure that optimizes complementarity and compatibility between these factors over relevant time periods. Biochar effects and behavior should also be modelled at temporal scales similar to its expected functional lifetime in soils. Finally, when existing soil data are insufficient, soil sampling and analysis procedures need to be described as part of a biochar certification procedure.O “biochar” tem um tempo de meia-vida no solo relativamente longo e pode alterar substancialmente as propriedades, processos e funções do solo. A perspectiva da aplicação de “biochar” aos solos, em escala global, evidencia a importância de se lhe atribuir um processo de certificação sofisticado e rigoroso. O objetivo deste trabalho foi discutir o conceito da integração das propriedades do “biochar” com os fatores ambientais e socioeconômicos relevantes do local de aplicação selecionado, como parte de um procedimento de certificação sustentável que otimize a complementaridade e a compatibilidade entre esses fatores, em períodos de tempo relevantes. Os efeitos e o comportamento do “biochar” devem, também, ser modelados em escalas temporais similares às de seu tempo de vida funcional nos solos do local selecionado. Finalmente, onde os dados existentes sobre as características do solo forem insuficientes, procedimentos de amostragem e análise do solo devem ser descritos como parte do procedimento de certificação do “biochar”.publishe

Reductions in soil surface albedo as a function of biochar application rate: implications for global radiative forcing

Biochar can be defined as pyrolysed (charred) biomass produced for application to soils with the aim of mitigating global climate change while improving soil functions. Sustainable biochar application to soils has been estimated to reduce global greenhouse gas emissions by 71–130 Pg CO2-Ce over 100 years, indicating an important potential to mitigate climate change. However, these estimates ignored changes in soil surface reflection by the application of dark-coloured biochar. Through a laboratory experiment we show a strong tendency for soil surface albedo to decrease as a power decay function with increasing biochar application rate, depending on soil moisture content, biochar application method and land use. Surface application of biochar resulted in strong reductions in soil surface albedo even at relatively low application rates. As a first assessment of the implications for climate change mitigation of these biochar–albedo relationships, we applied a first order global energy balance model to compare negative radiative forcings (from avoided CO2 emissions) with positive radiative forcings (from reduced soil surface albedos). For a global-scale biochar application equivalent to 120 t ha−1, we obtained reductions in negative radiative forcings of 5 and 11% for croplands and 11 and 23% for grasslands, when incorporating biochar into the topsoil or applying it to the soil surface, respectively. For a lower global biochar application rate (equivalent to 10 t ha−1), these reductions amounted to 13 and 44% for croplands and 28 and 94% for grasslands. Thus, our findings revealed the importance of including changes in soil surface albedo in studies assessing the net climate change mitigation potential of biochar, and we discuss the urgent need for field studies and more detailed spatiotemporal modelling.We thank L Montanarella (Joint Research Centre) for making this study possible, W Mehl for help with the spectroscopy work and P Drahota for the mineralogy analyses. We thank the Portuguese Fundação para a Ciência e a Tecnologia (FCT) for providing F G A Verheijen with a postdoctoral grant (SFRH/BPD/74108/2010), and further want to acknowledge the financial support of the Czech Science Foundation (under grant No. GA 526/09/1762), and the Marie Curie CIG grant (No. GA 526/09/1762). We thank two anonymous reviewers for strengthening the letter.publishe

Recarga artificial en Bajos Submeridionales

Se presenta la experiencia en desarrollo en un sector de Bajos Submeridionales próximo a Tostado, para monitorear los efectos de la recarga artificial de acuíferos. El objetivo del estudio es mejorar la disponibilidad de agua en calidad y cantidad para uso ganadero y evaluar una obra de recarga a partir de un pozo doble propósito recarga – bombeo para mejorar su eficiencia, y difundir estas prácticas.El área piloto se ubica en un paleocauce arenoso del río Salado. En el mismo se han realizado numerosos estudios geoeléctricos, de infiltración, sedimentológicos, químicos recuperación de niveles, de suelos y de recarga. Además se dispone de una estación meteorológica automática, caudalímetro y freatímetros. Se realizó un análisis de eventos de recarga y su efecto sobre el sistema natural y en la obra. Se concluye que ha resultado exitosa y puede ser transferida a otros ambientes de paleocauces del chaco-santafesino.This work describes an artificial recharge experience of groundwater as source for animal beverage, de veloped on a livestock demonstrative unit, placed in Bajos Submeridionales, Santa Fe province, Argentina. The aim of this study is to improve quality and quantity of water for livestock use, analyze a recharge-pumping well efficiency, and finally to spread this practice in the region. The study area is located in a antique sandy channel of the Salado river, where have been conducted geoelectric studies, sedimentologic, soil and water analysis, pumping and recharge, and infiltration tests. Additionally, it counts with metheorological on-line data from an automatic station, flowmeter, and water-level measurements from digital and analogical devises. An analysis of a recharge event has been conducted in order to assess environmental changes and response of facilities. This successful experience suggests that these kinds of facilities could be applied in similar environments of chaco-santafesino region.Universidad Nacional de La Plat