Lowest Singlet Exciton in Pentacene: Modern Calculations versus Classic Experiments

Based on simple model calculations, the expected magnitude of the field‐induced shift observable in electroabsorption is estimated for three alternative assignments proposed in the literature for the lowest singlet excitation of the pentacene crystal (pure Frenkel exciton, pure charge‐transfer exciton, or a mixture of both). The results are compared with the corresponding experimental value, which is also known from the literature. The latter turns out to be compatible only with the mixed parentage of the pertinent state, which contains the charge‐transfer contribution in the range from 25 to 70 %. The conclusion is discussed in the context of the present controversies concerning the existing experimental and theoretical evidence on this subject.     

Surface plasmon resonance imaging biosensors for aromatase based on a potent inhibitor and a specific antibody: Sensor development and application for biological material

Aromatase (ARO) is an enzyme with potential diagnostic significance. Aberrant expression of aromatase in tissues is associated with a number of pathological conditions, including tumor of the breast, ovary, testes, liver, adrenal cortex and uterus, as well as endometriosis. Two methods for the highly selective determination of ARO concentration in human tissues by using of two different biosensors co-operating with the surface plasmon resonance imaging technique (SPRI) have been developed. One of the developed biosensors contains immobilised rabbit polyclonal antibody specific for aromatase (Y-ARO), while the other contains immobilized ARO inhibitor-exemestane (E-ARO). Both biosensors specifically bound ARO from analyzed samples. The analytically useful dynamic response range of both biosensors is between 0.3 and 5.0 ng mL^?1. The detection limit (3S.D.) of both biosensors is 90 pg mL^?1. Standard deviation of both biosensors is 1%. Recoveries of ARO spikes are between 97 and 108% for both biosensors under model conditions and for real samples. Albumin and alkaline phosphatase are tolerated for both biosensors up to 10,000 fold excess.      

Analytical methods for determination of benzodiazepines. A short review

Benzodiazepines (BDZs) are generally commonly used as anxiolytic and/or hypnotic drugs as a ligand of the GABA_A-benzodiazepine receptor. Moreover, some of benzodiazepines are widely used as an anti-depressive and sedative drugs, and also as anti-epileptic drugs and in some cases can be useful as an adjunct treatment in refractory epilepsies or anti-alcoholic therapy. High-performance liquid chromatography (HPLC) methods, thin-layer chromatography (TLC) methods, gas chromatography (GC) methods, capillary electrophoresis (CE) methods and some of spectrophotometric and spectrofluorometric methods were developed and have been extensively applied to the analysis of number of benzodiazepine derivative drugs (BDZs) providing reliable and accurate results. The available chemical methods for the determination of BDZs in biological materials and pharmaceutical formulations are reviewed in this work.      

Spectroscopic analysis of pindolol irradiated in the solid state

Pindolol ((2RS)-(1-(1H-indol-4-iloxy)-3- [(1-metyloetylo)amino]-2-propanol) in substantia was exposed to ionising radiation emitted by high energy electrons from an accelerator, in the standard sterilisation dose of 25 kGy and in higher doses from the range 50–400 kGy. The effects of irradiation were checked by spectrometric methods (UV, MS, FT-IR, EPR) and hyphenated methods (HPLC-MS) and the results were referred to those obtained for non-irradiated sample. EPR results indicated the presence of free radicals in irradiated samples, in the amount of 1.36 × 10¹⁶ spin g^?1 for 25 kGy and 3.70×10¹⁶ spin g^?1 for 400 kGy. The loss of pindolol content determined by HPLC was 1.34% after irradiation with 400 kGy, while the radiolytic yield of the total radiolysis for this dose of irradiation was 2.69×10⁷ mol J^?1. By means of HPLC-MS it was possible to separate and identify one product of radiolytic decomposition, which probably is 2-((R)-3-(1H-indol-4-yloxy)-2-hydroxypropylamino)propan-1-ol formed upon oxidation. In the range of sterilisation doses (25–50 kGy), pindolol was found to show high radiochemical stability and would probably be safely sterilised by the standard dose of 25 kGy.      

Disentangling steric and electronic factors in monomeric bis(2‐bromo‐4‐chloro‐6‐{[(2‐hydroxyethyl)imino]methyl}phenolato‐κ2N,O)copper(II)

The title compound, [Cu(C₉H₈BrClNO₂)₂], is a square‐planar complex. The potentially tridentate dibasic 2‐bromo‐4‐chloro‐6‐{[(2‐hydroxyethyl)imino]methyl}phenolate ligand coordinates in a trans‐bis fashion to the Cu^II centre via the imine N and phenolate O atoms. The Cu^II atom lies on the centre of inversion of the molecule. The potentially coordinating hydroxyethyl group remains protonated and uncoordinated, taking part in intermolecular hydrogen bonds with vicinal groups, leading to the formation of a two‐dimensional hydrogen‐bond network with sheets parallel to the (10) plane. Substituent effects on the crystal packing and coordination modes of the ligand are discussed.     

A one-particle potential integrable on a family of quadrics

It is shown that one particle in the potential ( - ∑ _k-1 ⁿ q _k ⁿ /a _k )^-1 is completely integrable and n independent rational integrals in involution are found. The restriction of this system to any quadric ∑ _k=1 ⁿ q _k ² /(a _k - z)=1 is integrable too. The system is separable in generalized elliptic coordinates. Supported in part by the Polish Ministry of Science, Technology and Higher Education, Project MR-1-7.     

Synthesis and ESI-MS Complexation Studies of New Macrocyclic Bisamides Containing Binaphthyl Unit

Eight new chiral macrocyclic bisamides, containing binaphthyl and some other aromatic (phenyl or naphthyl) subunits, are obtained in racemic form. Preliminary results concerning their ability for complexation of alkali metal cations, using ESI-MS technique, are presented.     

Gaussian fluctuations of characters of symmetric groups and of Young diagrams

We study asymptotics of reducible representations of the symmetric groups S _q for large q. We decompose such a representation as a sum of irreducible components (or, alternatively, Young diagrams) and we ask what is the character of a randomly chosen component (or, what is the shape of a randomly chosen Young diagram). Our main result is that for a large class of representations the fluctuations of characters (and fluctuations of the shape of the Young diagrams) are asymptotically Gaussian; in this way we generalize Kerov's central limit theorem. The considered class consists of representations for which the characters almost factorize and this class includes, for example, the left-regular representation (Plancherel measure), irreducible representations and tensor representations. This class is also closed under induction, restriction, outer product and tensor product of representations. Our main tool in the proof is the method of genus expansion, well known from the random matrix theory.     

A FORMALISM FOR SOME CLASS OF FORCING NOTIONS

We introduce a class of forcing notions, called forcing notions of type S, which contains among other Sacks forcing, Prikry-Silver forcing and their iterations and products with countable supports. We construct and investigate some formalism suitable for this forcing notions, which allows all standard tricks for iterations or products with countable supports of Sacks forcing. On the other hand it does not involve internal combinatorial structure of conditions of iterations or products. We prove that the class of forcing notions of type S is closed under products and certain iterations with countable supports.     

Topological Censorship for Kaluza–Klein Space-Times

The standard topological censorship theorems require asymptotic hypotheses which are too restrictive for several situations of interest. In this paper we prove a version of topological censorship under significantly weaker conditions, compatible, e.g., with solutions with Kaluza–Klein asymptotic behavior. In particular we prove simple connectedness of the quotient of the domain of outer communications by the group of symmetries for models which are asymptotically flat, or asymptotically anti-de Sitter, in a Kaluza–Klein sense. This allows one, e.g., to define the twist potentials needed for the reduction of the field equations in uniqueness theorems. Finally, the methods used to prove the above are used to show that weakly trapped compact surfaces cannot be seen from Scri. Gregory J. Galloway was supported in part by NSF Grant DMS-0708048.