The effects of PH, Ionic concentration and ionic species of dissolution media on the release rates of quinidine gluconate sustained release dosage forms

The dissolution profiles of some extended release quinidine gluconate products were shown to be dependent on several dissolution medium variables. It was shown that, for a quinidine gluconate wax matrix tablet, the dissolution rate has an unexpected inverse relationship to the solubility as a function of pH. The dissolution rate is also affected by the concentration of chloride ion present in the dissolution medium apparently due to the inhibition of disintegration. It was found that the nature of the anion (inorganic vs. organic) of the dissolution buffer plays a significant role in the release of the drug. Salts of inorganic acids used as part of the buffer system lower the rate of release of quinidine gluconate from wax matrix tablets through an inhibition of disintegration. On the other hand, buffer salts of organic acids do not have any appreciable effect on the disintegration or dissolution of these tablets. Since the concentration of chloride ion in both gastric and intestinal juices is approximately 0.1M, this suggests that the use of a dissolution medium containing chloride ion represents the more appropriate approach when an in-vivo/in-vitro correlation is desired. For all the quinidine gluconate controlled release formulations studied, mechanisms of release are of at least two different types. This makes the selection of a single dissolution medium for in-vivo/in-vitro correlations either improbable or impossible.     

Fibrosarcoma of the orbit (author's transl)

During a period of 8 months a capsulated orbital tumour--not adherent the orbital walls or the bulbus--developed in a 21-year-old female patient. The tumour was exstirpated in toto. The histological findings show a fibrosarcoma with poorly differentiated cells, giant cells and numerous mitoses. The comparatively small incidence of the tumour as well as the prognosis quoad vitam are discussed.     

On the theory of the ising model of the macromolecular solution

The partition function of a macromolecular binary solution is transposed in the partition function in Ising's model. On the basis of this model the macrocanonical function is explained by the presence of the interaction forces, in the one-dimensional as well as in the two-dimensional cases. The chemical potential of the macromolecular solution is calculated in both cases and compared with the results obtained by Flory and Huggins.     

Single-molecule assays of calmodulin target binding detected with a calmodulin energy-transfer construct

We have detected single-molecule binding interactions of a target peptide with the calcium-signaling protein calmodulin (CaM) immobilized in an agarose gel, and we have demonstrated the application of a single-molecule binding assay to measure the binding strength of CaM with the CaM-binding domain of calmodulin-dependent protein kinase II (CaMKII). The results demonstrate the potential for ultrasensitive assays of CaM-target interactions and the measurement of a picomolar dissociation constant. To detect single-molecule protein interactions, single-molecule assays require that the analyte molecule be confined to the focal spot of the objective for the time scale of the measurement. We demonstrate the deleterious effect of surface immobilization on CaM. As an alternative to surface immobilization, we have constructed a CaM/maltose binding protein fusion protein, which renders CaM translationally immobile in a low weight percent agarose gel. The target binding functionality of CaM assayed in agarose gels is in good agreement with solution assays. The utility of the construct for detecting interactions with CaM targets was demonstrated in a single-molecule assay of binding interactions of MBP-CaM with the CaMKII CaM-binding domain peptide. A value of 103 +/- 35 pM for the dissociation constant of this interaction was determined by simple counting of fluorescent molecules.     

Design and characterization of polypropylene matrix/glass fibers composite materials

In this article, polymer composites based on polypropylene (PP) matrix reinforced with short glass fibers type E (GF‐type E) were obtained. However, to ensure good interfacial adhesion and stress transfer across the interface, the influence of the chemical functionalization of the phases was analyzed. The better interfacial adhesion is assured by the use of maleic anhydride grafted PP and amino‐functionalized GF. The obtained composite materials were tested from the point of view of composition, morphology, and mechanical properties. It can conclude that the chemical functionalization of the two phases is beneficial from the point of view of compatibility of the phases and consequently higher mechanical properties are obtained. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42163.     

Investigation of Structural, Magnetic and Magnetotransport Properties of Electrodeposited Co–TiO2 Nanocomposite Films

Nanocomposite Co?CTiO₂ thin films were prepared by simultaneous electrodeposition of Co and TiO₂ on a Cu substrate from a solution based on Co sulfate in which TiO₂ nanoparticles were suspended by stirring. We investigated the influence of the TiO₂ nanoparticles concentration in the bath on the morphology, composition, magnetic and magnetotransport properties of the films. The Co?CTiO₂ thin films were characterized by using scanning electron microscopy, X-ray photoelectron spectroscopy and X-ray diffraction analyses, and their magnetic properties were evaluated by using an induction type device with data acquisition system and a torque magnetometer. The current in-plane transport properties of the films have been investigated. The results showed that the films were composed of a Co metal matrix containing embedded TiO₂ nanoparticles and cobalt hydroxide which is formed simultaneously with cobalt metal deposition. The amount of TiO₂ in the film increases with the rising concentration of TiO₂ nanoparticles in the plating bath. This complex structure favored the increase of the magnetoresistance. The Co?CTiO₂ nanocomposite films (containing about 1.3 at.% Ti) exhibit a giant magnetoresistance contribution of 47.6 %. From the magnetic measurements, we have found that the saturation magnetization, the magnetic susceptibility, and the effective magnetic anisotropy constant decrease with the increasing content of TiO₂ in the thin layer. The easy magnetization axis direction changes from in-plane to almost perpendicular-to-plane, with increasing TiO₂ nanoparticles content in the film. The existence of a giant magnetoresistance effect in Co?CTiO₂ is very promising for potential applications in spintronics.     

A behavioral change-based approach to energy efficiency in a manufacturing plant

In the realm of industrial energy efficiency studies, very little research has been done to understand the barriers and opportunities to influence behavior of production workers and the corresponding energy-saving potentials. This paper analyzes a case study of Volvo Construction Equipment AB in Braås, Sweden (VCE Braås), that has reduced its relative idle electricity use by more than 10 percentage points during 2013–2016 by implementing a strategy of changing everyday behavior of production workers. The results based on interviews with actors involved in the energy efficiency project showed that a concrete goal, the employment of a fulltime operational leader who earlier worked as a production worker at VCE Braås, and the involvement of both the leadership and employees in project management were key to the success of the project.