Characterization of proteins in latex of the opium poppy (Papaver somniferum) using two-dimensional gel electrophoresis and microsequencing

The opium poppy (Papaver somniferum) belongs to the group of latex-containing plants. Latex is the milky-like fluid within laticifer cells. In this study, poppy latex was analyzed with respect to ultrastructure, alkaloid, and protein content. The main goal of this project was the examination of the proteins by two-dimensional gel electrophoresis. In a proteomics approach, we investigated two main fractions of the latex, namely the cytosolic serum and the sedimented fraction containing the alkaloid-accumulating vesicles. Of the serum, representing the protein-rich part of the latex, 75 spots were analyzed by internal peptide microsequencing, followed by a database searching. For 69 proteins a function could be assigned due to homology to known proteins, whereas six spots could not be identified. Furthermore, codeinone reductase, a representative of the specific enzyme system in morphine biosynthesis, could be detected within the cytosolic serum fraction. In the vesicle-containing pellet, 23 protein spots were analyzed. An attempt was also made to separate the vesicle pellet by density centrifugation, followed by investigation of the alkaloid content, ultrastructure, and protein pattern. This study describes the first database of soluble proteins present in the latex of P. somniferum     

A thermodynamic surface model for caesium sorption on bentonite

Caesium sorption on Wyoming bentonite MX-80 has been studied in solutions of NaCl, KCl, MgCl₂, CaCl₂, NaNO₃ and Ca (NO₃)₂ of concentrations varying between 0.025 and 1 mol/L, as well as in a weakly saline (I=0.004 ml/L) and a strongly saline (I=0.46 mol/L) natural groundwater. These experiments have been used to derive a thermodynamic model for the interaction of caesium with the bentonite surface in accordance with a surface chemical model, including acid/base reactions developed recently for montmorillonite. The sorption behaviour of caesium on bentonite can be described, within the experimental and model uncertainties, in terms of a one-site ion exchange model. The ion exchange constant obtained for the reaction NaX+Cs⁺CsX+Na⁺ (where X represents the ion exchange sites on montmorillonite) is log₁₀K⁰_ex=1.6. Impurities in the bentonite, influencing the concentrations of competing cations, such as Na⁺, K⁺, Mg²⁺ and Ca²⁺, have a crucial impact on the sorption of caesium. This impact can be adequately quantified with the present model. The model predictions compare well with sorption data published in the open literature on both Wyoming bentonite MX-80 and other types of bentonite. Distribution coefficients from the literature obtained from both batch and diffusion experiments and varying over four orders of magnitude are reproduced and explained successfully by the model.     

β-Lactam Derivatives as Enzyme Inhibitors: Peptidic Derivatives of (<Emphasis Type="Italic">RS</Emphasis>)-2-Oxo-4-phenylazetidine-1-alkanoic Acids

Summary. 4-Phenylazetidine-2-one was transformed into 4-phenylazetidine-1-alkanoic acids, which were reacted in the presence of diphenylphosphoroazidate with amino acid esters and dipeptide esters yielding β-lactam peptides with different spacers between the lactam ring and the peptide moiety. All structures were established by elementary analyses, HPLC, optical rotation, and spectroscopic data and all new compounds were tested as inhibitors of PPE using standard procedures. Four compounds exhibited a weak activity compared with the standard inhibitor trifluoroacetyl-l-val-l-tyr-l-val.     

On the choice of γ for singly-implicit RK or Rosenbrock methods

Following the slogan a picture is better than thousand data, for restricted Padé approximations with one realm-fold pole atz=1/ of orderm, we plot the error constants, the maximal error for negative realz as functions of, as well as the regions ofA- resp.A(0)-stability.     

Chemical and environmental sampling: quality through accreditation, certification and industrial standards

Executive summary In the CEN/STAR Trends Analysis workshop on Sampling, initiated by request of the Nordic Innovation Centre, specially invited experts provided presentations on demands about regulation concerning sampling quality, sampling standard developments, quality assurance systems and practical experience from different sampling situations and cases. The workshop arrived at recommendations on the importance of proper sampling for environmental and product control purposes, especially to support European regulations, trade agreements and monitoring of environment. Sampling is an integrated part of the whole measurement process and should therefore be especially considered from the viewpoint of the end-user of the results. There is a need for raising quality control issues in sampling and for the establishment of a more uniformly co-ordinated European quality system for sampling. With the standard methods available, there are in principle two different ways of achieving third party assessment of the sampling protocols and procedures: accreditation of sampling organisations based upon international, national, or in-house standards and methods, and certification of individual samplers’ competences for sampling. Several activities or efforts as well as research and standardisation needs for raising the quality issues in sampling were identified and presented in a paper by the workshop.All the presentations and Workshop Proceedings are electronically available on the Nordic Innovation Centre's web site at and more specifically at     

Simultaneous quantitative and qualitative analysis of aliskiren,enalapril and its active metabolite enalaprilat in undiluted human urine utilizing LC‐ESI‐MS/MS

The benefit–risk ratio of combined blocking by the direct renin inhibitor aliskiren and an angiotensin‐converting enzyme inhibitor (e.g. enalapril) on the renin–angiotensin–aldosterone system is discussed. No method was available for simultaneous determination of both drugs in urine. A novel sensitive method for simultaneous quantification in undiluted human urine was developed which enables systematic pharmacokinetic investigations, especially in poorly investigated populations like children. Matrix effects were clearly reduced by applying solid‐phase extraction followed by a chromatographic separation on Xselect^TM C₁₈ CSH columns. Mobile phase consisted of methanol and water, both acidified with formic acid. Under gradient conditions and a flow rate of 0.4 mL/min the column effluent was monitored by tandem mass spectrometry with electrospray ionization. Calibration curves were constructed in the range of 9.4–9600 ng/mL regarding aliskiren, 11.6–12000 ng/mL for enalapril and 8.8–9000 ng/mL for enalaprilat. All curves were analyzed utilizing 1/x²‐weighted quadratic squared regression. Intra‐run and inter‐run precision were 3.2–5.8% and 6.1–10.3% for aliskiren, 2.4–6.1% and 3.9–7.9% for enalapril as well as 3.1–9.4% and 4.7–12.7% regarding enalaprilat. Selectivity, accuracy and stability results comply with current international bioanalysis guidelines. The fully validated method was successfully applied to a pharmacokinetic investigation in healthy volunteers. Copyright © 2014 John Wiley & Sons, Ltd.     

D = 5 Einstein-Maxwell-Chern-Simons black holes

Five-dimensional Einstein-Maxwell-Chern-Simons theory with a Chern-Simons coefficient lambda = 1 has supersymmetric black holes with a vanishing horizon angular velocity but finite angular momentum. Here supersymmetry is associated with a borderline between stability and instability, since for lambda > 1 a rotational instability arises, where counterrotating black holes appear, whose horizon rotates in the opposite sense to the angular momentum. For lambda > 2 black holes are no longer uniquely characterized by their global charges, and rotating black holes with vanishing angular momentum appear.     

Numerical Studies of the Influence of the Porosity on Macroscopic Elastic Properties of Carbon/Carbon Composites

Material parameter identification of the carbon/carbon composites was provided using numerical implementation of semi-analytical methods and FE-calculations. The distribution of the fibers and pores obtained from microstructural studies is used as input for homogenization schemes for the determination of the effective elastic constants. The predictions are compared to experimental results. (© 2010 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim)     

Thermal diffusion behavior of nonionic surfactants in water

We studied the thermal diffusion behavior of hexaethylene glycol monododecyl ether (C12E6) in water by means of thermal diffusion forced Rayleigh scattering (TDFRS) and determined Soret coefficients, thermal diffusion coefficients, and diffusion constants at different temperatures and concentrations. At low surfactant concentrations, the measured Soret coefficient is positive, which implies that surfactant micelles move toward the cold region in a temperature gradient. For C12E6/water at a high surfactant concentration of w1 = 90 wt % and a temperature of T = 25 degrees C, however, a negative Soret coefficient S(T) was observed. Because the concentration part of the TDFRS diffraction signal for binary systems is expected to consist of a single mode, we were surprised to find a second, slow mode for C12E6/water system in a certain temperature and concentration range. To clarify the origin of this second mode, we investigated also, tetraethylene glycol monohexyl ether (C6E4), tetraethylene glycol monooctyl ether (C8E4), pentaethylene glycol monododecyl ether (C12E5), and octaethylene glycol monohexadecyl ether (C16E8) and compared the results with the previous results for octaethylene glycol monodecyl ether (C10E8). Except for C6E4 and C10E8, a second slow mode was observed in all systems usually for state points close to the phase boundary. The diffusion coefficient and Soret coefficient derived from the fast mode can be identified as the typical mutual diffusion and Soret coefficients of the micellar solutions and compare well with the independently determined diffusion coefficients in a dynamic light scattering experiment. Experiments with added salt show that the slow mode is suppressed by the addition of w(NaCl) = 0.02 mol/L sodium chloride. This suggests that the slow mode is related to the small amount of absorbing ionic dye, less than 10(-5) by weight, which is added in TDFRS experiments to create a temperature grating. The origin of the slow mode of the TDFRS signal will be tentatively interpreted in terms of a ternary mixture of neutral micelles, dye-charged micelles, and water.