From Regional to National Clouds: TV Coverage in the Czech Republic

Media, and particularly TV media, have a great impact on the general public. In recent years, spatial patterns of information and the relevance of intangible geographies have become increasingly important. Gatekeeping plays a critical role in the selection of information that is transformed into media. Therefore, gatekeeping, through national media, also co-forms the generation of mental maps. In this paper, correspondence analysis (a statistical method) combined with cloud lines (a new visual analytics technique) is used to analyze how individual major regional events in one of the post-communist countries, the Czech Republic, penetrate into the media on a national scale. Although national news should minimize distortions about regions, this assumption has not been verified by our research. Impressions presented by the media of selected regions that were markedly influenced by one or several events in those regions demonstrate that gatekeepers, especially news reporters, functioned as a filter by selecting only a few specific, and in many cases, unusual events for dissemination.     

Intermediate dosimetric quantities.

The transfer of energy from ionizing radiation to matter involves a series of steps. In wide ranges of their energy spectra photons and neutrons transfer energy to an irradiated medium almost exclusively by the production of charged particles which ionize and thereby produce electrons that can ionize in turn. The examination of these processes leads to a series of intermediate quantities. One of these is kerma, which has long been employed as a measure of the energy imparted in the first of the interactions. It depends only on the fluence of uncharged particles and is therefore--unlike absorbed dose and electron fluence--insensitive to local differences of receptor geometry and composition. An analogous quantity for charged-particle fields, cema (converted energy per unit mass), is defined, which quantifies the energy imparted in terms of the interactions of charged particles, disregarding energy dissipation by secondary electrons. Cema can be expressed as an integral over the fluence of ions times their stopping power. However, complications arise when the charged particles are electrons, and when their fluence cannot be separated from that of the secondaries. The resulting difficulty can be circumvented by the definition of reduced cema. This quantity corresponds largely to the concept employed in the cavity theory of Spencer and Attix. In reduced cema not all secondary electrons but all electrons below a chosen cutoff energy, delta, are considered to be absorbed locally. When the cutoff energy is reduced, cema approaches absorbed dose and thereby becomes sensitive to highly local differences in geometry or composition. With larger values of delta, reduced cema is a useful parameter to specify the dose-generating potential of a charged-particle field 'free in air' or in vacuo. It is nearly equal to the mean absorbed dose in a sphere with radius equal to the range of electrons of energy delta. Reduced cema is a function of the fluence at the specified location at and above the chosen cutoff energy. Its definition requires a modification of restricted linear collision stopping power, L delta, and it is recommended that the definition of L delta be so changed.     

Early prostaglandin E synthesis is an obligatory event in the induction of cell proliferation in mouse epidermis in vivo by the phorbol ester TPA

Following the topical application of the phorbol ester TPA to mouse skin $\text{in vivo}$ a rapid increase of the prostaglandin E content after 10 and 60 minutes was observed. Pretreatment of mouse skin with indomethacin abolished the first PGE peak as well as the cellular proliferation induced by TPA. Both effects could not be prevented when indomethacin was applied 30 to 60 minutes after TPA treatment, suggesting that the early increase in epidermal PGE is an obligatory event in the course of the induction of epidermal cell proliferation by TPA. A small increase of epidermal PGE was also seen after treatment with the TPA-analogue “Ti₈”, whereas 4-O-methyl-TPA was inactive in this respect. “Ti₈”-induced epidermal cell proliferation could be partially inhibited by indomethacin, whereas 4-O-methyl-TPA-induced cell proliferation was insensitive to the drug.     

Transdermal enhancement through rat skin of luciferase plasmid DNA loaded in elastic nanovesicles

Transdermal absorption of luciferase plasmid (pLuc) was enhanced by loading in elastic cationic liposomes and niosomes and the application of iontophoresis or the stratum corneum (SC) stripping method. Cationic liposomes (DPPC/Chol/DDAB at a 1:1:1 molar ratio) and niosomes (Tween61/Chol/DDAB at a 1:1:0.5 molar ratio) were prepared by the freeze-dried empty liposomes method. The elastic vesicles were prepared by hydrating the lipid or surfactant film by 25% of ethanol instead of distilled water. Gel electrophoresis of all nanovesicles showed the 100% pLuc entrapment efficiency. All nanovesicles loaded with pLuc showed larger vesicular sizes than the nonloaded vesicles of about 1.4 times for liposomes and 1.7 times for niosomes. The nanovesicles loaded with pLuc demonstrated less positive zeta potential than the nonloaded vesicles. The pLuc loaded in elastic vesicles kept at 4 ± 2 and 27 ± 2°C for 8 weeks gave the remaining pLuc of about 70 and 60% for liposomes and 85 and 73% for niosomes, respectively. For nonelastic vesicles kept at 4 ± 2°C, 56 and 61% of the remaining pLuc were observed for liposomes and niosomes, respectively, while at 27 ± 2°C, all pLuc were degraded. The deformability indices of the elastic liposomes and niosomes loaded with the pLuc were 16.64 ± 2.92 and 20.72 ± 0.82, whereas the nonelastic vesicles gave 9.35 ± 0.09 and 10.08 ± 0.12, respectively. Transdermal absorption through rat skin pretreated with SC stripping or treated with iontophoresis of pLuc loaded in nanovesicles by vertical Franz diffusion cells was investigated at 37°C. The cells were stopped and the skin and the receiving solution were withdrawn at 1, 3, and 6 hours and the pLuc contents in the stripped SC, whole skin (viable epidermis and dermis; VED), and the receiving solution were assayed by the modified gel electrophoresis and gel documentation. Without the SC stripping technique or iontophoresis, the pLuc loaded and nonloaded in nonelastic cationic liposomes or niosomes were not found in SC, VED, and receiving solution. The fluxes in the whole skin of pLuc loaded in nonelastic liposomes and niosomes with SC stripping and iontophoresis at 6 hours gave 2.73 ± 0.46 and 3.83 ± 0.73, and 7.01 ± 1.22 and 9.60 ± 1.31 g/cm²/h, respectively, while pLuc loaded in elastic liposomes and niosomes without the SC stripping and iontophoresis at 6 hours showed 2.79 ± 0.09 and 2.84 ± 0.04 g/cm²/h, respectively. The pLuc loaded in elastic niosomes or in nonelastic niosomes with iontophoresis was found in the receiving solution with a higher amount than that loaded in elastic liposomes or nonelastic liposomes with iontophoresis. The fluxes in the receiving solution of pLuc loaded in nonelastic liposomes and niosomes with iontophoresis at 6 hours were 6.71 ± 0.31 and 8.82 ± 0.28 g/cm²/h, respectively. For elastic liposomes and niosomes, the fluxes of the loaded pLuc in the receiving solution were the same, at about 1.9 g/cm²/h. Although pLuc loaded in nonelastic niosomes with iontophoresis gave the highest delivery of the plasmid in VED and receiving solution, a more promising applicable approach for gene delivery has been suggested to be the elastic niosomal systems, since no equipment is required.     

Chemical Synthesis and Cloning of a Gene Coding for Bacillus Subjilis Hbsu Protein

Abstract

A gene coding for Bacillus subtilis non-specifically DNA-binding HBsu protein has been chemically synthesized and cloned. The gene was designed to permit expression of the encoded protein in several ways.