Teratology information services in Europe and their contribution to the prevention of congenital anomalies

OBJECTIVES: To inform on Teratology Information Services (TIS) in Europe, their history, function and activity in preventing congenital malformations. CONCLUSIONS: Clinical teratology tries to identify human teratogens. TIS play an important role in public health by providing counsel on known reproductive risks and conducting specific research. This has led to a reduction in unnecessary fears of pregnant women and pregnancy terminations, as well as to better, more appropriate drug selection to treat acute or chronic disease. In addition, TIS units also conduct prospective studies and inform the public and physicians of the possible effects of environmental agents on the developing embryo and fetus.     

Lowest energy electronic transition in aqueous Cl(-) salts: Cl(-) → (H2O)6 charge transfer transition

We use UV resonance Raman spectroscopy to probe the lowest energy allowed electronic transitions of aqueous solutions containing Cl(-) salts. We show that the waters hydrating the Cl(-) are involved in charge transfer transitions that transfer electron density from Cl(-) to the water molecules. These charge transfer transitions cause significant change in the H-O-H bond angle in the excited state, which results in a strong enhancement of the preresonance Raman intensity of the water bending modes. Our work gives the first insight into the lowest allowed electronic transition of hydrated Cl(-).     

What's Wrong with These Observables?

An imprecise measurement of a dynamical variable (such as a spin component) does not, in general, give the value of another dynamical variable (such as a spin component along a slightly different direction). The result of the measurement cannot be interpreted as the value of any observable that has a classical analogue.     

Emergence of local realism in fuzzy observations of correlated quantum systems

A pair of spin-j particles, prepared in a singlet state, move away from each other and are examined by two distant observers. If the latter are able to discriminate between the2j+1 values of a component ofJ, there are pairs of observables whose correlation strongly violates Bell's inequality, for arbitrarily large j. However, if neighboring values are lumped together because of limited instrumental resolution, the observable correlations tend to those predicted by classical mechanics.Dedicated to Professor Henry Margenau, on the occasion of his 90th birthday.     

Laser excited luminescence spectra of zirconia

Luminescence spectra of ivory zirconia (Zr0₂) excited by an argon-ion laser (19,436–21,839 cm^?1) reveal a complex pattern consisting of both sharp and diffuse peaks in the 16,000–19,000 cm^?1 region. The intensity behavior of these features depends markedly on the excitation frequency. The sharp luminescence peaks of the 18,140–18,600 cm^?1 region are attributed to phonon-mediated de-excitation of excited states of the impuriity-doped ZrO₂ lattice. The more diffuse luminescence bands of the 17,700–18,000cm^?1 region may be associated with the electron traps observed in glow experiments and/or with higher-order phonon processes.     

A two model receptor system of the alpha1D adrenergic receptor to describe interactions with epinephrine and BMY7378

In this study, we have developed a two receptor model system to describe the R and R states of G-protein coupled receptors, specifically the alpha(1D) adrenergic receptor. The two models interact with agonist (epinephrine) and antagonist (BMY7378) differently. The active model has increased interactions with epinephrine. The inactive model has increased interactions with BMY7378. We also explored the protonation state of the ligands. When the most basic amine was protonated, we found increased hydrogen bonding and increased aromatic interactions. Protonated epinephrine hydrogen bonds with Asp176 and has aromatic residues Trp172, Trp235, Trp361, and Phe388 within 3 Angstroms. Protonated BMY7378 hydrogen bonds with Trp172 and Lys236 and has aromatic residues Trp172, Trp254, Phe364, Phe384, and Phe388 within 3 Angstroms. We conclude that the two model system is required to represent the two states of the receptor and that protonation of the ligand is also critical.     

Applications of asymmetric hydrosilylations mediated by catalytic (DTBM-SEGPHOS)CuH

[reaction: see text] Several aryl ketone precursors useful in the synthesis of known physiologically active compounds have been reduced to the corresponding nonracemic alcohols. The previously reported combination of a catalytic quantity of (R)-(-)-DTBM-SEGPHOS-ligated CuH and stoichiometric PMHS is shown to be very effective in these asymmetric hydrosilylations.     

Slow motion lineshapes

A slow motion expansion about the characteristic features of the powder spectrum is presented. Analytic expressions for the lineshape function, modulated by slow rotational diffusion, are derived. It is shown that the slow motion limit is characterized by harmonic oscillator equations of motion, and the resulting spectrum is determined by harmonic oscillator eigenvalues. The essential features of the lineshape show up naturally, and in particular the axial lineshape diverges like τ^1/4 while there is only a weak motional correction to the logarithmic divergence of the non-axial lineshape. The dynamic frequency shifts converge to their static limits like τ^-1/2 for all cases.