Mental representations of important real-life decisions

Two studies investigated how decision makers characterize alternatives in important real-life decisions, which they themselves had made (to leave a partner, to choose an education and to choose a home). First, the participants indicated a very high degree of involvement in the decisions studied and about half of the participants gave maximum involvement ratings for the partner decision. Second, the results showed that concepts that are essential in most decision theories, such as, consequence, probability and value were important characteristics of the decisions. Third, emotion, positive and negative affect were also important characteristics. Fourth, value and emotion were uncorrelated. Fifth, the patterns of characteristics of decisions made in the past did not differ markedly from the characteristics given to future decisions. Principal component analyses were performed on the ratings of applicability of the different characteristics across participants for each decision situation. Three factors were extracted. There was one factor for positive affect/emotions and another factor for negative affect/emotions verified in oblique solutions. Thus, different scales are needed to represent emotion/affect components (and not bipolar scales) in real-life important decisions. The third factor represented the way in which a decision was represented (moving pictures dialogue etc.). An analysis restricted to the participants who rated 100% involvement showed an additional fourth factor with “what others would think”, “similar situations”, “values” and “money” as the most prominent characteristics. This points to the importance of controlling for participant involvement in studies of human decision making to enable generalizations to real-life decisions.     

Enantiospecific synthesis of isomers of AES, a new environmentally friendly chelating agent

Three four-step enantiospecific syntheses of different diastereomers of AES, a new biodegradable chelating agent, are described. The stereocenters in each of the isomers are accessible from l- and d-malic and aspartic acids.     

ABSORPTION SPECTRAL SHIFTS OF CAROTENOIDS RELATED TO MEDIUM POLARIZABILITY

Abstract–Solvent induced absorption spectral shifts of the electronic transition from ground 1 A_g state to the excited 1B_u state in carotenoids have been studied. It is shown that the shift depends only on dispersion interactions in non-polar solvents. In polar media there is just a small extra contribution to the red-shift, due to other forms of interactions. The spectral shifts are well described by the theory, which expresses the shift relative to the gas phase value, as a function of solvent polarizability. The main conclusion is that the dominating mechanism behind the large red-shifted absorbance of carotenoids in the proteinacous environment, in vivo, is the mutual polarizability interactions between the carotenoids and the surrounding medium. The solution-phase values of the dipole moments of the lA_g to 1B_u transitions and the differences of isotropic polarizability between 1B_u and lA_g states of carotenoids in non-polar solvents are calculated and found to be around 13 D and 360 ų respectively. From the great overlap of absorption spectra between carotenoids in quinoline and carotenoids in vivo in purple bacterial antenna complexes, it can be expected that the carotenoids are surrounded by several aromatic amino acids in vivo. Comparisons have been done between the exicted states in carotenoids and in linear conjugated polyenes.     

The effect of water or salt solution on thin hydrophobic films

Hydrophobic films of polystyrene synthesized in bulk (PS) and by emulsion polymerization in the presence of the cationic surfactant cetyltrimethylammonium bromide (PS-CTAB) or the anionic surfactant sodium dodecyl sulfate (PS-SDS) were characterized by means of ellipsometry, contact angle measurements, and atomic force microscopy. Thin (approximately 65 nm) and thick (approximately 300 nm) films were spin-coated on hydrophilic silicon wafers. PS films presented scarcely tiny holes, while PS-CTAB and PS-SDS films presented holes and protuberances. The former were attributed to dewetting effects and the latter to surfactant clusters. The films were exposed to water or to a 0.1 mol/L NaCl solution for 24 h. Ex situ measurements evidenced strong topographic alterations after the exposure to the fluid. A model based on the diffusion of water (or electrolyte) molecules to the polymer/silcon dioxide interface through holes or defects on the film edges was proposed to explain the appearance of wrinkles and protuberances. In situ ellipsometric measurements were performed and compared with simulations, which considered either a water layer between a polymer and a silcon dioxide layer or an air layer between a polymer and water (medium). In the case of thin PS films, the ellipsometric angles evidenced a very thin (0.5-1.0 nm) air layer between water and the PS films. Upon increasing the PS film thickness, no air layer could be observed by ellipsometry. Regardless of the thickness, the ellipsometric data obtained for PS-CTAB and PS-SDS films did not indicate the presence of an air layer between them and the aqueous media. The dramatic changes in the topography of PS, PS-CTAB, and PS-SDS after immersion in salt solution were explained with proposed models. From a practical point of view, this study is particularly relevant because many hydrophobic polymers are used as substrates for biomedical purposes, where the physiological ionic strength is 0.15 mol/L NaCl.     

Trace analysis of heavy metals in high purity materials by helium-3 activation analysis

A method is described to determine traces of V, Fe, Ni, Zn, Nb and Mo in high purity matrices of niobium, tantalum and tungsten by non-destructive 14 MeV³He activation analysis. The influence of nuclear and γ-ray interferences in the determination of these elements is discussed.     

Unidirectional Littelmann Paths for Crystals of Type A and Rank 2

Algebras and Representation Theory - For the Kashiwara crystal of a highest weight representation of an affine Lie algebra of type A and rank e, with highest weight Λ, there is a labeling by...     

Phage-display selection of a human single-chain fv antibody highly specific for melanoma and breast cancer cells using a chemoenzymatically synthesized G(M3)-carbohydrate antigen

Overexpression of the cell-surface glycosphingolipid G(M3) is associated with a number of different cancers, including those of the skin, colon, breast, and lung. Antibodies against the G(M3) epitope have potential application as therapeutic agents in the treatment of these cancers. We describe the chemoenzymatic synthesis of two G(M3)-derived reagents and their use in the panning of a phage-displayed human single-chain Fv (scFv) antibody library derived from the blood of cancer patients. Three scFv-phage clones, GM3A6, GM3A8, and GM3A15, were selected for recombinant expression and were characterized using BIAcore and flow cytometry. BIAcore measurements using the purified, soluble scFvs yielded dissociation constants (K(d)) ranging from 4.2 x 10(-7) to 2.1 x 10(-5) M. Flow cytometry was used to evaluate the ability of each scFv to discriminate between normal human cells (human dermal fibroblast, HDFa), melanoma cells (HMV-1, M21, and C-8161), and breast cancer cells (BCM-1, BCM-2, and BMS). GM3A6 displayed cross-reactivity with normal cells, as well as tumor cells, and GM3A15 possessed little or no binding activity toward any of the cell lines tested. However, GM3A8 bound to five of the six tumor cell lines and showed no measurable reactivity against the HDFa cells. Hence, we have demonstrated that a synthetic G(M3) panning reagent can be used to isolate a fully human scFv that is highly specific for native G(M3) on the surface of tumor cells. The result is a significant step toward effective immunotherapies for the treatment of cancer.     

Über Struktur und Aktivität der den H2O2-Zerfall katalysierenden Cu2+-Komplexe. V. Vergleich der katalytischen Aktivität der Cu2+-Komplexe isomerer β-Hydroxythiophen-Derivate. Mettallionen und H2O2, 9. Mitteilung

The catalytic properties in H₂O₂ decomposition of the Cu²⁺-chelates of 2- Acetyl-3-hydroxy-thiophene (I) and 3-Acetyl-4-hydroxy-thiophene (II) have been investigated. Evidence is given that the catalytic activity of the chelates is a function of the respective bond orders of the α, β (I) and β, β′ (II) thiophene bonds of the chelate ring.     

Enhancement of the catalytic activity of [Cu2(TS)(OH)2(OAc)] using superconductor cuprate sample

A superconducting sample (Nd_0.1Y_0.9Ba₂Cu₃O_7-δ) has been tried as a catalyst for H₂O₂ decomposition. All parameters affecting the reaction rate (concentration of H₂O₂, weight of catalyst, temperature and pH) were studied and the optimum conditions were evaluated. A mixture of the superconducting cuprate with [Cu₂(TS)(OH)(OAc)] using different percentages of the sample has been prepared and tried kinetically under the same mentioned conditions. An attempt was made to increase the activity of the complex. The data show that the cuprate sample alone was found to be almost inactive when compared with that of the mixture. The catalytic mechanism in the absence and presence of the complex was suggested.     

Unbounded derivations and invariant states

Let be a von Neumann algebra with a cyclic and separating vector . Let =i[H, ·] be the spatial derivation implemented by a selfadjoint operatorH, such thatH=0. Let be the modular operator associated with the pair (, ). We prove the equivalence of the following three conditions:1)H is essential selfadjoint onD(), andH commutes strongly with .2) The restriction ofH toD() is essential selfadjoint onD(^1/2) equipped with the inner product(|)_#=(|)+(^1/2|^1/2), , D(^1/2).3) exp (itH) exp (–itH)= for anyt.We show by an example, that the first part of 1),H is essential selfadjoint onD(), does not imply 3). This disproves a conjecture due to Bratteli and Robinson [3].Part of this work was done while O.B. was a member of Zentrum für interdisziplinäre Forschung der Universität Bielefeld