Isorepresentations of the Lie-Isotopic SU(2) Algebra with Applications to Nuclear Physics and to Local Realism

In this note, we study the nonlinear-nonlocal-noncanonical, axiom-preserving isotopies/Q-operator deformations SÛ_Q(2) of the SU(2) spin-isospin symmetry. We prove the local isomorphism SÛ_Q(2)SU(2), construct and classify the isorepresentations of SÛ_Q(2), identify the emerging generalizations of Pauli matrices, and show their lack of unitary equivalence to the conventional representations. The theory is applied for the reconstruction of the exact SU(2)-isospin symmetry in nuclear physics with equal p and n masses in isospaces. We also prove that Bell's inequality and the von Neumann theorem are inapplicable under isotopies, thus permitting the isotopic completion/Q-operator deformation of quantum mechanics studied in this note which is considerably along the celebrated argument by Einstein, Podolsky and Rosen.     

Enhanced transfection efficiency of multicomponent lipoplexes in the regime of optimal membrane charge density

Recently, membrane charge density of lipid membranes, sigma M, has been recognized as a universal parameter that controls the transfection efficiency of complexes made of binary cationic liposomes and DNA (binary lipoplexes). Three distinct regimes, most likely related to interactions between complexes and cells, have also been identified. The purpose of this work was to investigate the transfection efficiency behavior of multicomponent lipoplexes in the regime of optimal membrane charge density (1< sigma M < 2 x 10 (-2) e/A (2)) and compare their performance with that of binary lipoplexes usually employed for gene delivery purposes. We found remarkable differences in transfection efficiency due to lipid composition, with maximum in efficiency being obtained when multicomponent lipoplexes were used to transfect NIH 3T3 cells, while binary lipoplexes were definitely less efficient. These findings suggested that multicomponent systems are especially promising lipoplex candidates. With the aim of providing new insights into the mechanism of transfection, we investigated the structural evolution of lipoplexes when interacting with anionic (cellular) lipids by means of synchrotron small-angle X-ray diffraction (SAXD), while the extent of DNA release upon interaction with anionic lipids was measured by electrophoresis on agarose gels. Interestingly, a clear trend was found that the transfection activity increased with the number of lipid components. These results highlight the compositional properties of carrier lipid/cellular lipid mixtures as decisive factors for transfection and suggest a strategy for the rational design of superior cationic lipid carriers.     

Stereoselective dioxirane hydroxylations and the synthesis of tripod boronic acid esters

Methyl(trifluoromethyl)dioxirane (TFDO, 1b), a powerful yet selective oxidant, was employed to achieve in high yield the direct stereoselective hydroxylation at tert-CH of cis,cis-1,3,5-trimethylcyclohexane (4), yielding triol 7 bearing all-axial disposition of the three OH groups. Similarly, TFDO oxidation of 1,3- and of 1,4-dimethylcyclohexane gave the corresponding Z-diols 5 and 6, respectively. Triol 7 was a convenient starting material to synthesize a novel borate—that is, 1-bora-2,8,9-trioxa-3,5,7-trimethyladamantane (8)—having a peculiar cage-shaped ‘tripod’ structure. From triol 7, novel tripod arylboronic Brönsted-assisted Lewis acids (BLA) could be obtained, as exemplified by 10a and 10b.     

Dimerisation of urea in water solution: a quantum mechanical investigation

The effect of water solvation on the structure and stability of cyclic dimers of urea has been investigated with the aid of density functional theory at the B3LYP/6-311++G** level. Several hydration models have been discussed. Specific solvent effects have been simulated through single and multiple water-urea interactions involving all the hydration sites of urea. The bulk solvent effects have been estimated through polarised continuum models. Under all the hydration patterns cyclic dimers continue to be stable structures although the solvent weakens the urea-urea interaction. Single and multiple specific urea-water interactions are competitive with urea dimerisation. The anticooperative nature of the two intermolecular interactions is largely due to the changes on sigma- and pi-electron density of urea caused by hydrogen bonding with water. The stability of the dimer is however, lost within a few ps when the hydrated dimer is described by a quantum mechanical molecular dynamics approach (ADMP). The cyclic dimer evolves towards structures where urea molecules are linked not more directly but through water molecules which have a bridge function.     

In Vitro Monitoring of Live Cardiomyocytes Dynamics by a Scanning Near Field Optical Microscope Setup

We describe an original scanning near field optical microscope setup developed to examine rhythmically beating cardiac myocytes fully immersed in culture media. Scans could be halted at any point to record localized contraction profiles. Contractions could be detected with high sub nanometric vertical sensitivity and changed shape dramatically within adjacent sub micron-sized areas. We believe that the spatial dependency of contractions arises because of system’s ability to resolve the dynamic behavior of individual sub membrane actin bundles. Our results, combining imaging and real time recording in localized areas, reveal a new, non-invasive method for studying sub micron morphological activity in live biological samples.This paper was originally presented at the 5th International Conference on NEAR FIELD OPTICS and RELATED TECHNLOGIES (NFO-5), which was held on December 6–10, 1998 at Coganoi Bay Hotel, Shirahama, Japan, in cooperation with the Japan Society of Applied Physics and Mombusho Grant-in Aid for Scientific Research on Priority Areas “Near-Field Nano-optics” Projects, sponsored by Japan Society for the Promotion of Science.     

Stability-Indicating Liquid Chromatography–Spectrophotometric UV Method for the Simultaneous Determination of Marbofloxacin,Dexamethasone and Clotrimazole in a Liquid Pharmaceutical Dosage Form

A novel, simple and reliable reversed-phase liquid chromatography (LC)–spectrophotometric UV stability-indicating method was developed and validated for the simultaneous assay of marbofloxacin, clotrimazole and dexamethasone acetate in the presence of their impurities and degradation products in a pharmaceutical formulation for veterinary use. A C18 (75 × 4.6 mm, 4 µm) column was used with an acetonitrile–ammonium acetate mixture as mobile phase delivered with gradient elution. A diode-array detection was used in the 200–400 nm range and the detection wavelength was set at 260 nm. Validation carried out on the pharmaceutical dosage form, according to Veterinary International Conference on Harmonization guidelines, demonstrated excellent specificity, linearity, precision, accuracy and robustness. Excellent specificity with respect to vehicle and degradation products obtained after forced degradation (i.e., oxidation, acid, alkaline and thermal degradation) was demonstrated. As for linearity, the LC–UV assay method is applicable in the 0.180–0.420 mg mL⁻¹ concentration range for marbofloxacin (r ² = 0.99), 0.060–0.140 mg mL⁻¹ for dexamethasone acetate (r ² = 0.97) and 0.600–1.400 mg mL⁻¹ for clotrimazole (r ² = 0.98). Very good repeatability (RSD < 0.8 %) and inter-day precision (RSD < 2.5 %) were observed for all analytes. Accuracy was in the 93–104 %, 98–111 % and 99–108 % confidence interval (95 %) for marbofloxacin, dexamethasone acetate and clotrimazole, respectively. The variations (±20 %) of mobile phase flow rate and pH, and oven column temperature did not exhibit an impact on the analyte content accuracy, demonstrating the robustness of the method. The LC–UV method here developed and validated may be used routinely for quality control.

     

Stability-Indicating Liquid Chromatography–Spectrophotometric UV Method for the Simultaneous Determination of Marbofloxacin,Dexamethasone and Clotrimazole in a Liquid Pharmaceutical Dosage Form

A novel, simple and reliable reversed-phase liquid chromatography (LC)–spectrophotometric UV stability-indicating method was developed and validated for the simultaneous assay of marbofloxacin, clotrimazole and dexamethasone acetate in the presence of their impurities and degradation products in a pharmaceutical formulation for veterinary use. A C18 (75 × 4.6 mm, 4 µm) column was used with an acetonitrile–ammonium acetate mixture as mobile phase delivered with gradient elution. A diode-array detection was used in the 200–400 nm range and the detection wavelength was set at 260 nm. Validation carried out on the pharmaceutical dosage form, according to Veterinary International Conference on Harmonization guidelines, demonstrated excellent specificity, linearity, precision, accuracy and robustness. Excellent specificity with respect to vehicle and degradation products obtained after forced degradation (i.e., oxidation, acid, alkaline and thermal degradation) was demonstrated. As for linearity, the LC–UV assay method is applicable in the 0.180–0.420 mg mL^?1 concentration range for marbofloxacin (r ² = 0.99), 0.060–0.140 mg mL^?1 for dexamethasone acetate (r ² = 0.97) and 0.600–1.400 mg mL^?1 for clotrimazole (r ² = 0.98). Very good repeatability (RSD < 0.8 %) and inter-day precision (RSD < 2.5 %) were observed for all analytes. Accuracy was in the 93–104 %, 98–111 % and 99–108 % confidence interval (95 %) for marbofloxacin, dexamethasone acetate and clotrimazole, respectively. The variations (±20 %) of mobile phase flow rate and pH, and oven column temperature did not exhibit an impact on the analyte content accuracy, demonstrating the robustness of the method. The LC–UV method here developed and validated may be used routinely for quality control.     

New Problematic Aspects of Current String Theories and Their Invariant Resolution

We identify new, rather serious, physical and mathematical inconsistencies of the current formulation of noncanonical or nonunitary string theories due to the lack of invariant units necessary for consistent measurements, lack of preservation in time of Hermiticity-observability, and other shortcomings. We propose three novel reformulations of string theories for matter of progressively increasing complexity via the novel iso-, geno-, and hyper-mathematics of hadronic mechanics, which resolve the current inconsistencies, while offering new intriguing possibilities, such as: an axiomatically consistent and invariant inclusion of gravity, the reduction of macroscopic irreversibility to the most primitive level of vibrations of the universal substratum (ether), or the treatment of multi-valued, irreducible, biological structures. We then identify three corresponding classical formulations of string theories for antimatter via the novel anti-isomorphic isodual mathematics. We finally outline the intriguing features of the emerging new cosmologies (including biological structures, as it should be for all cosmologies), such as: universal invariance (rather than covariance) under a symmetry isomorphic to the Poincaré group and its isodual; equal distributions of matter and antimatter in the universe (as a limit case); continuous creation; no need for the missing mass; significantly reduced dimensions; possibility of experimental identification of antimatter in the universe; identically null total characteristics of time, energy, linear and angular momentum, charge, etc.; and other intriguing features.