Decision support for the selection of reference sites using 137Cs as a soil erosion tracer

The classical approach of using 137Cs as a soil erosion tracer is based on the comparison between stable reference sites and sites affected by soil redistribution processes; it enables the derivation of soil erosion and deposition rates. The method is associated with potentially large sources of uncertainty with major parts of this uncertainty being associated with the selection of the reference sites. We propose a decision support tool to Check the Suitability of reference Sites (CheSS). Commonly, the variation among 137Cs inventories of spatial replicate reference samples is taken as the sole criterion to decide on the suitability of a reference inventory. Here we propose an extension of this procedure using a repeated sampling approach, in which the reference sites are resampled after a certain time period. Suitable reference sites are expected to present no significant temporal variation in their decay-corrected 137Cs depth profiles. Possible causes of variation are assessed by a decision tree. More specifically, the decision tree tests for (i) uncertainty connected to small-scale variability in 137Cs due to its heterogeneous initial fallout (such as in areas affected by the Chernobyl fallout), (ii) signs of erosion or deposition processes and (iii) artefacts due to the collection, preparation and measurement of the samples; (iv) finally, if none of the above can be assigned, this variation might be attributed to "turbation" processes (e.g. bioturbation, cryoturbation and mechanical turbation, such as avalanches or rockfalls). CheSS was exemplarily applied in one Swiss alpine valley where the apparent temporal variability called into question the suitability of the selected reference sites. In general we suggest the application of CheSS as a first step towards a comprehensible approach to test for the suitability of reference sites

Surface Emissions Modulate Indoor SVOC Concentrations through Volatility-Dependent Partitioning.

Measurements by semivolatile thermal desorption aerosol gas chromatography (SV-TAG) were used to investigate how semivolatile organic compounds (SVOCs) partition among indoor reservoirs in (1) a manufactured test house under controlled conditions (HOMEChem campaign) and (2) a single-family residence when vacant (H2 campaign). Data for phthalate diesters and siloxanes suggest that volatility-dependent partitioning processes modulate airborne SVOC concentrations through interactions with surface-laden condensed-phase reservoirs. Airborne concentrations of SVOCs with vapor pressures in the range of C13 to C23 alkanes were observed to be correlated with indoor air temperature. Observed temperature dependencies were quantitatively similar to theoretical predictions that assumed a surface-air boundary layer with equilibrium partitioning maintained at the air-surface interface. Airborne concentrations of SVOCs with vapor pressures corresponding to C25 to C31 alkanes correlated with airborne particle mass concentration. For SVOCs with higher vapor pressures, which are expected to be predominantly gaseous, correlations with particle mass concentration were weak or nonexistent. During primary particle emission events, enhanced gas-phase emissions from condensed-phase reservoirs partitioned to airborne particles, contributing substantially to organic particulate matter. An emission event related to oven-usage was inferred to deposit siloxanes in condensed-phase reservoirs throughout the house, leading to the possibility of reemission during subsequent periods with high particle loading

Relación entre eficiencia de uso del nitrógeno y calidad industrial en variedades argentinas de Trigo Pan (Triticum Aestivum L.) con distinta composición de gluten

El uso eficiente del nitrógeno en los cultivos permite minimizar los riesgos ambientales y maximizar los ingresos de los productores. Esto se puede lograr ajustando el manejo de la fertilización y utilizando la variabilidad genética existente. Además de su efecto sobre el rendimiento, el N ejerce un importante efecto sobre la calidad de los granos de trigo. Esto último también es influenciado por la composición proteica del gluten y el ambiente. El objetivo del presente trabajo fue estudiar la relación entre la eficiencia de captura de N y su partición entre grano y rastrojo con atributos de calidad industrial en variedades argentinas de trigo pan de distinto ciclo y con diferente composición alélica de gliadinas y gluteninas. Los ensayos se realizaron durante la campaña 2011/12 en Azul, Buenos Aires (Argentina) incluyendo 27 variedades argentinas de trigo pan de distinto ciclo. Los tratamientos fueron testigo (T) y fertilizado (F) con aplicación repartida de urea para alcanzar 210 kg N/ha. Se determinaron rendimiento y sus componentes, se calcularon parámetros de eficiencia de uso de N y se realizaron mediciones de parámetros alveográficos, volumen de sedimentación, contenido de proteínas y de gluten húmedo en grano y contenido de N en rastrojo. El patrón proteico de cada variedad se identificó mediante geles de poliacrilamida. El genotipo resultó la principal fuente de variación para las eficiencias de recuperación de N total, en grano y en rastrojo. El índice de cosecha de N disminuyó de 0,81 en los tratamientos testigo a 0,73 en los fertilizados en promedio, existiendo interacción variedad*tratamiento. El contenido de proteínas en los granos y la extensibilidad de las masas fueron altamente dependientes del nivel de N en tanto que la fuerza panadera lo fue del genotipo. La capacidad de particionar N a grano explicó la relación existente entre extensibilidad y eficiencia de recuperación de N. La valoración de alelos de gluteninas de alto peso molecular no coincidió estrictamente con el Grupo de Calidad de la variedad evidenciando la influencia de otras fracciones proteicas y su interacción con el ambiente. La expresión del potencial genético atribuido a la composición alélica del gluten podría estar regulada en parte por atributos de eficiencia de uso de N.The efficient use of nitrogen in crops can minimize environmental risks and maximize returns to farmers. This can be achieved by adjusting the fertilization management and/or using the genetic variability. In addition to its effect on yield, N has a significant effect on the quality of wheat grains. The latter is also influenced by the gluten protein composition and the environment. The aim of this work was to study the relationship between N recovery efficiency and its partitioning between grain and stover with industrial quality attributes in Argentinean bread wheat varieties of different cycle and with different allelic composition of gliadins and glutenins. In the current work, field trials of 27 Argentinean bread wheat varieties of different cycle were carried out during 2011/12 season, in Azul, Province of Buenos Aires, Argentina. The fertilizer treatments were: control treatment (T) and fertilized treatment (F) with split application of urea at variable rates to reach 210 kg N/ha. The following characteristics were determined: grain yield and its components, parameters of N use efficiency, alveographic parameters, sedimentation volume, protein content, wet gluten content and N stover content. The protein pattern of each variety was identified by polyacrylamide gels. The genotype was the main source of variation for total recovery efficiency, grain recovery efficiency and stover recovery efficiency. The N harvest index decreased from 0.81 in control to 0.73 in fertilized treatments on average, and variety*treatment interaction was significant. The protein content in grains and the dough extensibility were highly dependent on the level of N while the baking strength it was of the genotype. The ability to partition N to grain explained the relationship between the extensibility and the N recovery efficiency. The assessment of high molecular weight glutenin alleles was not strictly coincided with Quality Group of the variety showing the influence of other protein fractions and their interaction with the environment. The expression of the genetic potential attributed to the allelic composition of gluten may be regulated in part by N use efficiency attributes.Gerencia de Comunicación e Imagen InstitucionalFil: Lerner, Silvia E. Universidad Nacional del Centro de la Provincia de Buenos Aires. Facultad de Agronomía. Departamento de Producción Vegetal, Cereales y Oleaginosas, Laboratorio de Valoración de Calidad Industrial de Trigo; ArgentinaFil: Arata, A.F. Universidad Nacional del Centro de la Provincia de Buenos Aires. Facultad de Agronomía. Departamento de Producción Vegetal, Cereales y Oleaginosas, Laboratorio de Valoración de Calidad Industrial de Trigo; ArgentinaFil: Arrigoni, A.C. Universidad Nacional del Centro de la Provincia de Buenos Aires. Facultad de Agronomía. Departamento de Producción Vegetal, Cereales y Oleaginosas, Laboratorio de Valoración de Calidad Industrial de Trigo; Argentin

Do bilinguals have different concepts? The case of shape and material in Japanese L2 users of English

An experiment investigated whether Japanese speakers’ categorisation of objects and substances as shape or material is influenced by acquiring English, based on Imai and Gentner (1997). Subjects were presented with an item such as a cork pyramid and asked to choose between two other items that matched it for shape (plastic pyramid) or for material (piece of cork). The hypotheses were that for simple objects the number of shape-based categorisations would increase according to experience of English and that the preference for shape and material-based categorisations of Japanese speakers of English would differ from mono¬lingual speakers of both languages. Subjects were 18 adult Japanese users of English who had lived in English-speaking countries between 6 months and 3 years (short-stay group), and 18 who had lived in English-speaking countries for 3 years or more (long-stay group). Both groups achieved above criterion on an English vocabulary test. Results were: both groups preferred material responses for simple objects and substances but not for complex objects, in line with Japanese mono¬linguals, but the long-stay group showed more shape preference than the short-stay group and also were less different from Americans. These effects of acquiring a second language on categorisation have implications for conceptual representation and methodology

Synthesis of a new chiral bis-arsine ligand based on natural carbohydrates

Transition-metal-catalyzed asymmetric allylic substitutions have become one of the most powerful tools for asymmetric C−C bond formation.1 Chiral diphosphine ligands have been some of the largest classes of ligands used in asymmetric substitutions. Trost developed the chiral ligand, which played a crucial role in the improvement of Pdcatalyzed asymmetric substitutions.2 Based on the Trost modular ligand (TML) system 3 a family of ligands has been prepared. We recently reported the synthesis and application of the novel chiral bis-arsine ligand 2 derived from TML.http://blucherproceedings.com.br/articles/details/2323Fil: Parajón Puenzoa, Sol C. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Departamento de Química Orgánica; Argentina.Fil: Parajón Puenzoa, Sol C. Universidad Nacional de Córdoba. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones en Físico-química de Córdoba; Argentina.Fil: Parajón Puenzoa, Sol C. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina.Fil: Parajón Puenzoa, Sol C. Universidad de Buenos Aires. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro de Investigaciones en Hidratos de Carbonos; Argentina.Fil: Arata Badano, Joaquín. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Departamento de Química Orgánica; Argentina.Fil: Arata Badano, Joaquín. Universidad Nacional de Córdoba. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones en Físico-química de Córdoba; Argentina.Fil: Lopez Vidal, Martin G. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Departamento de Química Orgánica; Argentina.Fil: Lopez Vidal, Martin G. Universidad Nacional de Córdoba. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones en Físico-química de Córdoba; Argentina.Fil: Varela, Oscar. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina.Fil: Varela, Oscar. Universidad de Buenos Aires. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro de Investigaciones en Hidratos de Carbonos; Argentina.Fil: Martín, Sandra E. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Departamento de Química Orgánica; Argentina.Fil: Martín, Sandra E. Universidad Nacional de Córdoba. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones en Físico-química de Córdoba; Argentina.Química Orgánic

Surface deoxidation mechanism during vacuum heat treatment of stainless steels AISI 304 and 446

A process of removal of surface oxides from stainless steels AISI 304 and 446 that involves reduction by residual carbon, followed by the formation and desorption of carbon monoxide, is studied by investigation of thermal desorption with quadrupole mass spectrometry (QMS) and secondary ion mass spectrometry (SIMS). Carbon monoxide desorption is studied as a function of time and temperature by QMS, and carbon diffusion due to heat treatment is studied with SIMS—twice as much carbon monoxide desorbs from AISI 304 overall and desorption sets in at 900 °C as opposed to 1100 °C for AISI 446. In samples heated to 900 °C, carbon shows surface enrichment in AISI 304 but depletion in AISI 446

MAXI GSC observations of a spectral state transition in the black hole candidate XTE J1752-223

We present the first results on the black hole candidate XTE J1752-223 from the Gas Slit Camera (GSC) on-board the Monitor of All-sky X-ray Image (MAXI) on the International Space Station. Including the onset of the outburst reported by the Proportional Counter Array on-board the Rossi X-ray Timing Explorer on 2009 October 23, the MAXI/GSC has been monitoring this source approximately 10 times per day with a high sensitivity in the 2-20 keV band. XTE J1752-223 was initially in the low/hard state during the first 3 months. An anti-correlated behavior between the 2-4 keV and 4-20 keV bands were observed around January 20, 2010, indicating that the source exhibited the spectral transition to the high/soft state. A transient radio jet may have been ejected when the source was in the intermediate state where the spectrum was roughly explained by a power-law with a photon index of 2.5-3.0. The unusually long period in the initial low/hard state implies a slow variation in the mass accretion rate, and the dramatic soft X-ray increase may be explained by a sudden appearance of the accretion disk component with a relatively low innermost temperature (0.4-0.7 keV). Such a low temperature might suggest that the maximum accretion rate was just above the critical gas evaporation rate required for the state transition.Comment: Publication of Astronomical Society of Japan Vol.62, No.5 (2010) [in print

Bright X-ray flares from the BL Lac object Mrk 421, detected with MAXI in 2010 January and February

Strong X-ray flares from the blazar Mrk 421 were detected in 2010 January and February through the 7 month monitoring with the MAXI GSC. The maximum 2 -- 10 keV flux in the January and February flares was measured as 120 +- 10 mCrab and 164 +- 17 mCrab respectively; the latter is the highest among those reported from the object. A comparison of the MAXI and Swift BAT data suggests a convex X-ray spectrum with an approximated photon index of about 2. This spectrum is consistent with a picture that MAXI is observing near the synchrotron peak frequency. The source exhibited a spectral variation during these flares, slightly different from those in the previous observations, in which the positive correlation between the flux and hardness was widely reported. By equating the halving decay timescale in the January flare, $t_{\rm d} \sim 2.5 \times 10^{4}$ s, to the synchrotron cooling time, the magnetic field was evaluated as B = 0.045 G $(\delta/10)^{-1/3}$, where $\delta$ is the jet beaming factor. Assuming that the light crossing time of the emission region is shorter than the doubling rise time, $t_{\rm r} \lesssim 2 \times 10^{4}$ s, the region size was roughly estimated as $R < 6 \times 10^{15}$ cm $(\delta/10)$. These are consistent with the values previously reported. For the February flare, the rise time, $t_{\rm r} < 1.3 \times 10^{5}$ s, gives a loose upper limit on the size as $R < 4 \times 10^{16}$ cm $(\delta/10)$, although the longer decay time $t_{\rm d} \sim 1.4 \times 10^{5}$ s, indicates B = 0.015 G $(\delta/10)^{-1/3}$, which is weaker than the previous results. This could be reconciled by invoking a scenario that this flare is a superposition of unresolved events with a shorter timescale.Comment: 14 pages, 4 figures, accepted for PASJ (Vol. 62 No. 6