Electrical impedance of ethylene-carbon monoxide/propylene-carbon monoxide (<Emphasis Type="Italic">EPEC</Emphasis>-<Emphasis Type="Italic">69</Emphasis>) thermoplastic polyketone

Electrical impedance technique was employed to investigate the electrical properties of ethylene-carbon monoxide/propylene-carbon monoxide terpolymer (EPEC-69). The measurements were performed in the frequency range 0.1–10⁵ Hz and in the temperature range 30–110 °C. The results reveal that the dielectric constant, loss factor, modulus, and ac conductivity are dependent of frequency and temperature. A Debye relaxation peak was detected in the plot of Z″ versus frequency where the activation energy was determined and found to be 1.26 eV. When the surface phenomenon effects were separated using the imaginary part of the complex admittance a second dielectric dispersion was observed in the low frequency region. Two models were proposed from the impedance measurements depending on temperature range.     

Evolution of chromosomal abnormalities in sequential cytogenetic studies of ataxia telangiectasia

Sequential cytogenetic studies of four patients with ataxia telangiectasia showed the progressive development of lymphocyte clones, each marked with a rearranged chromosome 14. Initial studies had shown random chromosomal breaks and rearrangements. Later studies in all patients showed nonrandom rearrangement of chromosome 14 with a breakpoint at 14q12 and with the distal segment translocated to either chromosome 14 or 7. The proportion of circulating lymphocytes carrying the marker tended to increase with time, accounting for the majority of the lymphocytes eventually in one case. The marked lymphocyte clones evolved further, as a result of loss of the small centric portions of the rearranged chromosome 14 (14pter leads to 14q12). Perhaps the abnormal clones in ataxia telangiectasia escape immunologic surveillance and flourish in an immunologically impaired environment. Subsequent to the loss of the centric portion of the rearranged chromosome 14, the cells may acquire additional capabilities that enhance malignant transformation.     

Mechanism of CO and O3 sensing on WO3 surfaces: First principle study

The microscopic mechanism of O₃ and CO sensing on WO₃ surfaces is clarified by a first principle study. It is shown that ozone reduces to O₂ on the (0 0 1) surface of WO₃ decreasing in such a way the number of oxygen vacancies and the conductivity (since oxygen vacancies act as donors in WO₃). The mechanism of CO sensing is just the opposite: the CO molecule is oxidized to CO₂ on the WO₃ surface increasing the number of oxygen vacancies and the conductivity. The reaction enthalpy for the reduction process of O₃ is found to be −2.54 eV in local density approximation (LDA) and −2.86 in generalized gradient approximation (GGA). The corresponding values for CO are −1.73 eV (LDA) and −1.52 eV (GGA). The adsorptions of O₃ and CO without reduction or oxidation are also calculated but the related energies are much smaller.     

Novel instantly-dispersible nanocarrier powder system (IDNPs) for intranasal delivery of dapoxetine hydrochloride: in-vitro optimization,ex-vivo permeation studies,and in-vivo evaluation

Dapoxetine (D) suffers from poor oral bioavailability (42%) due to extensive metabolism in the liver. The aim of this study was to enhance the bioavailability of D via preparing instantly-dispersible nanocarrier powder system (IDNPs) for intranasal delivery of D. IDNPs were prepared using the thin film hydration technique, followed by freeze-drying to obtain easily reconstituted powder providing rapid and ready method of administration. The produced nanocarrier systems were evaluated for drug content, entrapment efficiency percentage, particle size, polydispersity index, zeta potential, and drug payload. The optimized nanocarrier system was morphologically evaluated via transmission electron microscopy and the optimized freeze-dried IDNPs were evaluated for ex-vivo permeation and in-vivo pharmacokinetic studies in rabbits following intranasal and oral administration. The relative bioavailability of D after intranasal administration of freeze-dried IDNPs was about 235.41% compared to its corresponding oral nanocarrier formulation. The enhanced D permeation and improved bioavailability suggest that IDNPs could be a promising model for intranasal delivery of drugs suffering from hepatic first pass effect.     

Solidification of metallic alloys under magnetic fields

The present paper is aimed at showing how solidification of metallic alloys can be influenced by AC or DC magnetic fields through various types of effects. The application of AC magnetic fields leads to the generation of either fluid flows or vibration. It has been shown both numerically and experimentally that the electromagnetically-driven flows created by travelling or rotating magnetic fields promoted segregations and influenced their distribution. The flow may also promote the CET thanks to its effects on both the temperature and solute fields as well as the possible fragmentation mechanism. As far as DC magnetic fields are concerned, it was known that they usually exert a damping of the bulk fluid flows. However, it has been shown recently that for some alloys high intensity magnetic field interacts with the small thermoelectric current to create significant electromagnetic forces which are responsible for strong liquid metal flows both in the bulk and in the mushy zone. Orientation changes as well as possible modifications of thermodynamic properties were also observed.     

Dirac-fock total energies, ionization energies, and orbital energies for uranium ions U I to U XCII

Listed here are the orbital energies, total energies, and ionization energies for ground-state configurations of uranium ions U I to U XCII. These values have been computed with the relativistic Dirac-Fock code due to Desclaux. The ground-state electronic configuration for each ion is determined by comparing the total energies of neighboring configurations and selecting the one with the minimum value. The ionization energies are obtained by building differences between the total energies of the respective ions with and without the valence electron. The term values of the uranium ions have been assigned through comparison with the term values of ionized atoms with the same configuration and the same number of electrons as given in the tables of Moore. The tables presented here should find application in the calculation of opacities in uranium plasmas.     

Assessment of the bioactive lipid profiles of oil extracted from Tunisian table olive cultivars (Barouni,Besbassi, and Marsaline cvs.)

Bioactive compounds are components extracted from biological matrices that may offer physiological health benefits and have nutritive value. The present study characterized bioactive lipid components such as fatty acids, phytosterols, policosanol, and triterpenes from table olives. The table olives were processed according to the green Spanish-style method. The obtained results indicate that phytosterol fraction constitutes the major portion of the total unsaponifiable matter. The analysis of phytosterols showed the presence of 11 compounds, β-sitosterol the predominant one. The policosanol composition indicated that hexacosanol, tetracosanol, octacosanol, and docosanol were the main compounds, accounting for over 85% of total policosanols. Pentacyclic triterpenes (cycloartenol and 24-methylene cycloartenol) were found at a higher level (over 85%) compared to tetracyclic triterpenes (β-amyrin, δ-amyrin). These findings reveal that processed table olives contain an interesting amount of various bioactive compounds compared to marine and other floral biological matrices. Thus, processed table olives represent an interesting natural functional food that presents high stability and bioavailability of their natural bioactive ingredients. Practical Applications: Nowadays, with health food gaining popularity among consumers, the demand for natural bioactive compounds and functional food is expanding considerably all over the world. This study focuses on analyzing bioactive lipid components from processed table olives. Fruits were processed according to the green Spanish-style method. The salt content of the brine was adjusted to the minimum sodium chloride value required by the Codex Alimentarius Comission, which is 5%, taking into consideration people suffering from hypertension. This concentration is considered the minimum amount of salt necessary to exhibit antibacterial activities. Considering the results obtained, processed table olives present one of the most valuable potential resources for bioactive lipid compounds and have a considerable ability to preserve the stability of their lipid components. Thus, the food industry in Mediterranean countries can promote processed table olives as conventional functional food with no need for any enrichment or fortification.