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Two-color optical measurements of thermodiffusion in ternary mixtures frequently suffer from ill-conditioned contrast factor matrices, whose inversion leads to very large experimental errors. In this contribution, we show how the error amplification can be avoided in situations where a priori knowledge about the directions of the eigenvectors of the diffusion matrix is available. We present optical beam deflection experiments on solutions of the polymer polystyrene of Mw = 4880 g/mol in a mixed solvent of toluene and cyclohexane. In this system, the two diffusion eigenvalues differ by almost one order of magnitude. The large eigenvalue can be attributed to the interdiffusion of the two solvents and the small one to the polymer diffusion relative to the mixed solvent. The pre-selection of the eigenvectors renders the method stable against fluctuations of the experimental parameters. Both the diffusion and the Soret coefficients attributed to the two modes agree very well with the respective values of corresponding binary mixtures. [ABSTRACT FROM AUTHOR]

We have determined nonisothermal diffusive transport coefficients of a succinonitrile-(d)camphor mixture with a composition of c = 0.239 wt.-frac. (d)camphor at a temperature of 318.2 K, which is close to the eutectic point. The employed experimental techniques are optical beam deflection in a Soret cell and photon correlation spectroscopy. The diffusion coefficient is D = (1.43 ± 0.04) × 10−10 m2 s−1, the thermodiffusion coefficient is DT = (2.00 ± 0.06) × 10−12 m2 s−1 K−1, and the Soret coefficient is ST = (1.40 ± 0.02) × 10−2 K−1. Camphor migrates toward the lower and succinonitrile migrates toward the higher temperatures. While the diffusion coefficient is in good agreement with the literature, the Soret coefficient has been determined for the first time. Our analysis shows that a significant concentration shift can be established in the liquid mixture in the presence of a temperature gradient. The mixture has a negative separation ratio, which leads to convective instabilities if heated from above. [ABSTRACT FROM AUTHOR]

This work presents first on ground measurements of DCMIX 4 project ternary nanofluid Fullerene, 1,2,3,4-tetrahydronaphtalene and Toluene. Transport properties have been measured by Thermogravitational, Optical Digital Interferometry and Optical Beam Deflection techniques for concentration analysed in DCMIX 4 project, which refers to 0.0007 – 0.60 – 0.3993 and other fullerene concentrations around this value. Various thermophysical and optical properties which are necessary to determine thermodiffusion coefficients have been also measured.

Globally identifying mitigation options for the emission of reactive N gases from agricultural soils is a research priority. We investigated the effect of urea size and placement depth on sources and emissions of N gases from a Cambisol cropped to spring wheat (Triticum aestivum L.). In Exp. 1, wheat received either prilled urea (PU) mixed within the soil, urea super granule (USG; diam. 10.1 mm) point-placed at a soil-depth of 7.5 cm, or no N fertilizer. In Exp. 2, wheat received either USG (diam. 10.2 mm) point-placed at 2.5-, 5.0-, and 7.5-cm soil depths, or no N fertilizer. In both experiments, maximum peaks for nitrous oxide ([N.sub.2]O) fluxes and nitrification were delayed by 2 to 3 wk in the USG compared with the PU-treatment. The added [.sup.15]N-urea lost as [.sup.15]-[N.sub.2]O over 116 d was only 0.01% for both PU and USG treatments in Exp. 1. This loss for USGs was higher in Exp. 2 (0.02-0.15%) raeasured over 70 d, mainly related to higher moisture-induced denitrification. Temporal [N.sub.2]O fluxes were significantly related to changes in soil [NO.sub.3.sup.-]-N, water-filled pore space and [NH.sub.4.sup.+]-N ([R.sup.2] = 0.50, P < 0.05). However, the previous predictive model of Khalil et al. (2006) could best estimate its cumulative fluxes over time. The relative losses of ammonia (0.07-1.17%) and nitrogen oxides (0.19-1.54%) measured in Exp. 2 over 43 d decreased with increasing depths of USG placement. The USG point-placed at the 5.0- and 7.5-cm depths decreased the pooled gaseous N losses by 35 and 77%, respectively, over the shallower placement. The [.sup.15]N results imply that soil N could be the major source of [N.sub.2]O emissions (79-97%). Field studies are suggested to validate our findings that the deeper placement of USG can decrease N emissions under arable cropping. Abbreviations: DAE days after fertilization; [N.sub.2]O, nitrous oxide; PU, prilled urea; USG, urea super granule; WFPS, water-filled pore space.

Nitrification inhibitors (NIs) delay the oxidation of ammonium by soil microorganisms, maintaining a higher proportion of applied nitrogen (N) in the soil by preventing nitrate-N loss from leaching and gaseous N losses from nitrification and denitrification. Thus, a large number of studies have shown N fertilizers with NIs are more environmentally friendly. In contrast, there are only a limited number of studies about effects of the N fertilizers added with NIs on arable crop yields and the conclusions are also divergent. This study presents a meta-analysis of recent research in Germany investigating the effects of NIs on the yields of different agricultural crops (winter wheat, winter barley, winter rapeseed, potato, grain and silage maize) compared to conventional N fertilization without NIs at a given N rate. Crop yields with and without NIs at a reduced number of N fertilizer applications were also compared. Nitrogen fertilizers with NIs did not significantly influence the yields of all investigated crops. For a given N application rate, the number of fertilizer applications could be reduced by at least one without any significant effect on yield when fertilizers with NIs were used. By contrast, the crude protein content of winter wheat was decreased significantly when the number of applications of NI fertilizers was less than that of non-NI-containing fertilizers. These findings may suggest that the key advantages to using N fertilizers with NIs are helping to protect the environment due to reduced N losses and reducing labor costs due to saving at least one fertilizer application, all while maintaining the yields of the investigated crops. [ABSTRACT FROM AUTHOR]

Globally identifying mitigation options for the emission of reactive N gases from agricultural soils is a research priority. We investigated the effect of urea size and placement depth on sources and emissions of N gases from a Cambisol cropped to spring wheat ( Triticum aestivum L.). In Exp. 1, wheat received either prilled urea (PU) mixed within the soil, urea super granule (USG; diam. 10.1 mm) point-placed at a soil-depth of 7.5 cm, or no N fertilizer. In Exp. 2, wheat received either USG (diam. 10.2 mm) point-placed at 2.5-, 5.0-, and 7.5- cm soil depths, or no N fertilizer. In both experiments, maximum peaks for nitrous oxide (N2O) fluxes and nitrification were delayed by 2 to 3 wk in the USG compared with the PU treatment. The added 15N-urea lost as 15N-N2O over 116 d was only 0.01% for both PU and USG treatments in Exp. 1. This loss for USGs was higher in Exp. 2 (0.02-0.15%) measured over 70 d, mainly related to higher moisture-induced denitrification. Temporal N2O fluxes were significantly related to changes in soil NO3-N, water-filled pore space and NH4+-N (R² = 0.50, P< 0.05). However, the previous predictive model of Khalil etal. (2006) could best estimate its cumulative fluxes over time. The relative losses of ammonia (0.07-1.17%) and nitrogen oxides (0.19-1.54%) measured in Exp. 2 over 43 d decreased with increasing depths of USG placement. The USG point-placed at the 5.0- and 7.5-cm depths decreased the pooled gaseous N losses by 35 and 77%, respectively, over the shallower placement. The 15N results imply that soil N could be the major source of N2O emissions (79-97%). Field studies are suggested to validate our findings that the deeper placement of USG can decrease N emissions under arabic cropping. [ABSTRACT FROM AUTHOR]

The article offers information on the interlaboratory comparison (ILC) program which aims at continuously reviewing the reproducibility of lab test results, to ensure quality assurance for laboratories offering fertilizer analysis and to validate and revise analytical methods. It mentions information on the magnesium calcium carbonate fertilizer.

Objectives: Translation, adaptation, and validation of the German version of the SARC-F for community-dwelling older adults in Germany., Design: Cross-sectional., Setting and Participants: 117 community-dwelling outpatients with a mean age of 79.1 ± 5.2 years were included in the study; 94 (80.4%) of them were female. Sixty-three (53.8%) had a positive SARC-F score of ≥4 points. According to the definition of sarcopenia from the European Working Group on Sarcopenia in Older People (EWGSOP2), 8 patients (6.8%) were identified as sarcopenic and 57 (48.7%) as probable sarcopenic., Methods: According to EWGSOP2, probable sarcopenia was defined for patients with reduced hand grip strength (women: <16.0 kg; men: <27.0 kg) and/or impaired chair-rise time (both genders: >15 seconds). Patients with additional low skeletal muscle index were classified as sarcopenic (women: <5.5 kg/m 2 ; men: <7.0 kg/m 2 ). Translation and cultural adaption was composed of 7 different steps that were in general based on the guidelines put forward by the World Health Organization. Validation include test-retest and the inter-rater reliability (intraclass correlation coefficient) as well as internal consistency (Cronbach alpha). Furthermore, sensitivity, specificity, positive predictive value, and negative predictive value of the SARC-F were calculated. Receiver-operating characteristic analysis was performed to calculate the area under the curve., Results: The translated and culturally adapted version of the SARC-F for the German language has shown excellent inter-rater reliability and good test-retest reliability. The internal consistency is acceptable. Sensitivity (63%) and specificity (47%) for sarcopenia is low. For detecting patients with probable sarcopenia, the SARC-F in the German version has shown 75% sensitivity and 67% specificity., Conclusions and Implications: Because of a low sensitivity for detecting sarcopenia but an acceptable sensitivity for identifying probable sarcopenia, the German version of the SARC-F is a suitable tool for case finding of probable sarcopenia., (Copyright © 2019 AMDA – The Society for Post-Acute and Long-Term Care Medicine. Published by Elsevier Inc. All rights reserved.)

Imprecision studies, interference testing and multicentre method comparisons using patient samples were carried out with of a new point-of-care test for D-dimer (CARDIAC D-Dimer). The CV of the within-series and the day-to-day imprecision with blood samples and control materials were between 7% and 13%. Compared with Tina-quant D-Dimer, CARDIAC D-Dimer showed a good correlation and accuracy (n=353; r=0.91; y=1.06x-0.03), compared with STA LIATEST D-Dimer some poorer accuracy (n=304; r=0.91; y=1.12x-0.03). No interference was detected for different hematocrit values (16% to 51%) and in investigations with hemoglobin (up to 0.13 mmol/l), biotin (up to 30 microg/l), bilirubin (up to 340 micromol/l), intralipid (up to 31.1 mmol/l) and rheumatic factor (up to 79 IU/ml). Overdosing or underdosing by 10 microl did not affect the test result. The diagnostic sensitivity of CARDIAC D-Dimer for the detection of acute venous thromboembolic diseases was 100% in our study. With CARDIAC D-Dimer reliable quantitative D-dimer results can be easily obtained. Because of the good analytical and clinical agreement with Tina-quant D-Dimer, it should be suitable for ruling out venous thromboembolic diseases.