AN IN VITRO TEST FOR PHOTOINDUCED TOXICITY OF BENZOTHIADIAZINE DIURETICS USING BACTERIOPHAGE LAMBDA

Abstract— The relative photoinduced toxicity of five benzothiadiazine diuretics was assessed with respect to their potentiality to inactivate bacteriophage lambda by exposure to near-UV light in a semi-aqueous solution of 40% N,N-dimethylformamide. The results showed the following order for the toxicity on a quantum yield basis: penflutizide > trichlormethiazide > methichlothiazide > benzylhydrochlorothiazide > hydrochlorothiazide. Since the bacteriophage was inactivated even when mixed with preirradiated solutions of the diuretics, some photoproducts are responsible for the photoinduced toxicity of the diuretics. Although a lowered pH affected the infectivity, it was a minor factor.     

Electroinitiated Anionic Polymerization of Vinyl Monomers

Abstract

Polarographic reduction and electrolytically initiated anionic polymerization of various monomers have been investigated with tetra-n-butylammonium perchlorate in dimethoxyethane.     

A Characterization of Right Coideals of Quotient Type and its Application to Classification of Poisson Boundaries

Let be a co-amenable compact quantum group. We show that a right coideal of is of quotient type if and only if it is the range of a conditional expectation preserving the Haar state and is globally invariant under the left action of the dual discrete quantum group. We apply this result to the theory of Poisson boundaries introduced by Izumi for discrete quantum groups and generalize a work of Izumi-Neshveyev-Tuset on SU _q (N) for co-amenable compact quantum groups with the commutative fusion rules. More precisely, we prove that the Poisson integral is an isomorphism between the Poisson boundary and the right coideal of quotient type by a maximal quantum subgroup of Kac type. In particular, the Poisson boundary and the quantum flag manifold are isomorphic for any q-deformed classical compact Lie group.     

Studies on segmented polyurethane—urea elastomers: Structure of segmented polyurethane—urea based on poly(tetramethylene glycol), 4,4'-diphenylmethane diisocyanate,and 4,4'-diaminodiphenylmethane

Structure studies on the segmented polyurethane-urea based on poly(tetramethylene glycol), 4,4'-diphenylmethane diisocyanate, and 4,4'-diaminodiphenylmethane have been made using wide- and small-angle x-ray diffraction. It was found that the hard segments have a well-defined crystal structure indexed by a monoclinic unit cell with dimensions a = 4.72 Å, b = 11.33 Å, c (chain axis) = 11.64 Å, and γ = 116.5°. Further, the hard segments have an anisotropic supermolecular structure, that is, a spherulitic crystalline texture. The microdomain structure depends on the molecular weight of the soft segments, with phase separation becoming distinct with an increase in the molecular weight of the soft segment. Based on the long period observed in small-angle x-ray patterns of heat-set specimens, the thickness of lamellae was estimated to be about 93 Å. This corresponds to an average hard segment sequence length of 8. On deformation, the hard segment orients preferably transverse to the stretch direction up to high elongations, and it shows a hysteresis of orientation. This phenomenon can be explained in terms of the anisotropic supermolecular structure. Further, deviation from ideal rubber elasticity observed in the stress-strain relationships of the segmented polyure-thane-urea elastomers might also be caused by the anisotropic structure.     

General description of orientation factors in terms of expansion of orientation distribution function in a series of spherical harmonics

A mathematical representation of orientation distribution of structural units within the bulk polymer is given in terms of an expansion of the distribution function in a series of spherical harmonics. Each coefficient of the expanded series is discussed in general relation to the orientation factors, average degrees of orientation distribution, defined by several different authors independently. Several optical techniques to evaluate the orientation factors, the second and fourth moments of orientation distribution of crystalline and noncrystalline structural units from optical dichroic quantities, are discussed. Some graphical representations of the state of orientation are proposed, and the estimation of orientation distribution from the orientation factors of different orders is discussed quantitatively.     

Studies of the polymerization of diallyl compounds. XXVIII. Copolymerization of monoallyl phthalate with allyl benzoate and diallyl phthalate

The bulk copolymerizations of monoallyl phthalate (MAP) with allyl benzoate (ABz) and diallyl phthalate (DAP) were conducted in the presence of benzoyl peroxide as an initiator at 70°C; copolymers containing allyl alcohol unit were obtained. The copolymer composition was reasonably interpreted in terms of polymerization kinetics, including the partial elimination of phthalic anhydride (PhA) from the MAP growing chain end in its propagation reaction with another monomer. Kinetics of the copolymerization of DAP with MAP were also discussed in detail, and the gel point was additionally evaluated. DAP–MAP copolymer was homogeneously reacted with zinc acetate to produce the polymer gel carrying ionic crosslinkages.     

Gel‐to‐Sol and Sol‐to‐Gel Transitions Utilizing the Interaction of α‐Cyclodextrin with Dodecyl Side Chains Attached to a Poly(acrylic acid) Backbone

Summary: By utilizing the interaction of α‐cyclodextrin (α‐CD) with dodecyl side chains in polymers of x mol‐% dodecyl‐modified poly(acrylic acid) (p(AA/C₁₂(x))), systems that undergo gel‐to‐sol and sol‐to‐gel transitions were successfully constructed. Rheological experiments indicated that addition of α‐CD to the hydrogel of p(AA/C₁₂(5)) caused a drastic decrease in the viscosity, while addition of oligo(α‐CD) to the solution of p(AA/C₁₂(2)) led to a remarkable increase in the viscosity.

Photographs for a gel‐to‐sol transition upon addition of α‐CD to 5.0 g · L⁻¹ p(AA/C₁₂(5)).     

Vibration testing based on impulse response excited by pulsed-laser ablation: Measurement of frequency response function with detection-free input

We have developed a non-contact vibration-measurement system that is based on impulse excitation by laser ablation (i.e. laser excitation) to measure the high-frequency-vibration characteristics of objects. The proposed method makes it possible to analyse the frequency response function just by measuring the output (acceleration response) of a test object excited by pulsed-laser ablation. This technique does not require detection of the input force. Firstly, using a rigid block, the pulsed-laser-ablation force is calibrated via Newton's second law. Secondly, an experiment is conducted in which an object whose natural frequency lies in the high-frequency domain is excited by pulsed-laser ablation. The complex frequency spectrum obtained by Fourier transform of the measured response is then divided by the estimated pulsed-laser-ablation force. Finally, because of the error involved in the trigger position of the response with respect to the impulse arrival time, the phase of the complex Fourier transform is modified by accounting for the response dead time. The result is the frequency response function of the object. The effectiveness of the proposed method is demonstrated by a vibration test of an aluminium block.