Electric and magnetic fields of the closed depolarization front in the anisotropic myocardium

On the basis of the bidomain model of anisotropic myocardium, mathematical relationships for calculating the characteristics of the extracellular electric and magnetic fields outside a closed or open depolarization front were derived on the assumption that the generator and fields are axially symmetric with respect to the longitudinal direction of the fibres making up the excitable tissue. The spatial configuration of the fields was determined and quantitative estimates were obtained for the electric potential and magnetic induction caused solely by the macroscopic anisotropy of the myocardium tissue as a volume conductor.     

Green fluorescent protein (GFP) as a marker during pollen development

The transient expression of three mutant forms of green fluorescent protein (GFP) genes, GFP4, GFP5ER, and GFP4S65C, under several constitutive and pollenspecific promoters throughout pollen development in Nicotianatabacum, thaliana and Antirrhinummajus is described. Immature pollen of tobacco, Arabidopsis and snapdragon, isolated at different developmental stages, were bombarded with plasmids containing the GFP and cultured in vitro for several days until maturity. The expression of GFP was monitored every day during in vitro maturation, germination and pollination, as well as after in situ pollination. The expression pattern of each construct was compared in parallel experiments to that of ßglucuronidase (GUS) constructs expressed by the same promoters. The results show that the expression level of all three GFP mutant forms was dependent on the strength of the promoter used. The strongest promoter was the DC3 promoter, and no notable differences in the intensity and brightness of all three versions of GFP were observed. GFPexpressing pollen from tobacco and snapdragon developed in vitro for several days until maturity and germinated in vitro as well as on the surface of stigmata, strongly suggesting that all three GFPs are not toxic for the development of functional pollen. Furthermore, stably transformed tobacco plants expressing GFP under the control of the strong pollenexpressed DC3 and LAT52 promoters were not impaired in reproductive function, confirming that GFP can be used as a nondestructive marker for plant reproductive biology and development.     

An elementary bioelectrical generator of the anisotropic homogeneous myocardium and its extracellular field

On the basis of the bidomain model that takes into account the electric anisotropy of body tissues, analytical relationships were developed for calculating the characteristics of electric and magnetic fields produced by an elementary (dipole) bioelectric generator that arises in the electrogenic excitable tissue of the myocardium. The errors in the identification of intensity and location of the bioelectric generator in the myocardium were estimated from the measurements of its external fields (noninvasive identification of the excited region) using approximate methods based on isotropic models of the physical medium.     

Genetic Diversity Between Japanese and Chinese Threeline Grunt (<Emphasis Type="Italic">Parapristipoma trilineatum</Emphasis>) Examined by Microsatellite DNA Markers

Threeline grunt (Parapristipoma trilineatum) distributes around the southwestern coast of Japan and the east coast of China. The Chinese P. trilineatum was imported by Japan as an aquacultural seed because of its rapid growth compared with that of the Japanese P. trilineatum. The Japanese P. trilineatum differs from the Chinese P. trilineatum in some quantitative traits, and it has been suggested that these two P. trilineatum populations are genetically different. In order to identify the population structures around Japan and China, 5 local populations of the Japanese P. trilineatum and 2 local populations of the Chinese P. trilineatum were analyzed using 4 microsatellite DNA markers. Significant differences were detected between Japanese and Chinese P. trilineatum and among samples of Chinese P. trilineatum; however, among the samples of Japanese P. trilineatum, no significant differences were detected. These results suggest that care must be taken to prevent the escape of the Chinese P. trilineatum from culture cages around the Japanese coast, in order to preserve the genetically different population structures of Japanese and Chinese P. trilineatum.     

Interactions between larvae of the hoverfly <Emphasis Type="Italic">Eristalinus sepulchralis</Emphasis> and microorganisms in the hydrothermal springs of the Uzon caldera,Kamchatka

The physicochemical and microbial characteristics of some medium-temperature hydrotherms of Kamchatka Peninsula (Uzon caldera), habitats of the hoverfly Eristalinus sepulchralis larvae, were studied. In these hydrothermal vents, the larvae were found to use various prokaryotic and eukaryotic microorganisms as a nutrient substrate. The rates of chemo-and photosynthetic activity of the suspended microbial communities inhabiting the hydrotherms and supporting the existence of larvae were measured. By light and electron microscopy, exo-and endosymbiotic prokaryotic microorganisms were revealed in the digestive and respiratory systems of larvae.     

Comparative analysis of algal biodiversity in the rivers of Israel

Comparative analysis of algal communities in the rivers of Israel was completed to highlight the influence of environmental variables on biodiversity. The study revealed that 671 species of algae and cyanobacteria belonging to nine taxonomic divisions were present during 2002–2009 in the Yarqon, Alexander, Hadera, Qishon, Oren, Lower and Upper Jordan, and Zin rivers. The species richness of each river was evaluated by taxonomic structural comparison, geobotanical, hierarchical cluster analysis, and the degree of relatedness for different levels of taxonomic resolution. The analysis revealed close similarity of the Upper Jordan and Oren rivers. The average taxonomic distinctness index showed that the Yarqon, Oren, Upper Jordan, and Qishon communities were partly degraded due to permanent environmental disturbances. The variation in taxonomic distinctness index showed that the Alexander, Yarqon and Hadera communities were formed not only due to anthropogenic factors but also through long-term climatic impact. The most abundant indicator species inhabit low streaming and standing alkaline waters of medium salinity and low to medium organic pollution. The statistical approaches allowed discrimination between climatic and anthropogenic factors that impact upon the riverine biodiversity in semi-arid environments. Analysis shows the influence of anthropogenic factors was strongly modulated by climatic impacts causing a marked decease of species richness from north to south.     

Changes in the lungs in the early period of closed trauma of the thorax in rats

In experiments on rats it has been demonstrated that in the acute period of uninjured parts of the lungs periodic changes of protein, lipid and glucose concentrations developed. In uninjured parts of the lungs one can observe more concentration of lipids and in injured parts-more glucose. The changes of substrates, concentrations in the lungs are due to not only the changes of venous blood excess in the lungs, but are connected with metabolic changes in the cells of the injured and uninjured parts of the lungs. The metabolic changes in the lungs in the acute period of chest trauma influence the creation of such indices of gas exchange as PaCO2 and PACO2.     

Algal communities of the Hadera River (Israel) under dramatic niche changes

The Hadera River is the most polluted among the Mediterranean coastal rivers of Israel due to abundant E. coli, high concentrations of heavy metals and nutrients, and high temperatures. In 2003–2008 we found 191 species of algae and cyanobacteria belonging to seven taxonomic divisions. The upper reaches were dominated by cyanobacteria and exhibited levels of toxic pollution. Downstream, the ecological niches of algal communities dramatically changed: upper stream diversity first increased and then decreased due to the influx of rainwater in the tidal zone during winter. On one hand, seasonal dynamics show that in winter, inorganic contamination was reduced because of dilution by the influx of rainwater, but, on the other hand, organic pollution increased from agriculture. Down the river, diversity increases and the community composition undergoes considerable change. In summer, algal blooms indicate a reduction of stress and aid in the river’s self-purification. The WESI indices and RPI show steady year-round stressful conditions for algal photosynthesis with increasing instability in the river. Perpetuation of the current situation would disturb the self-purification capacity of the river ecosystem through destruction of biotic components. Statistical analysis (CCA) reveals the impact of wastewater as the most important stress factor for the Hadera River ecosystem, which is an exceptionally strong example of self-purification.     

Synthesis and structures of bimetallic silicon-containing imido alkylidene complexes of molybdenum Me2Si[CHMo(NAr)(ORF3)2]2 and PhVinSi[CHMo(NAr)(ORF3)2]2

Bimetallic alkylidene complexes of molybdenum (R_F3O)₂(ArN)MoCH-SiMe₂-CHMo(NAr)(OR_F3)₂ (1) and (R_F3O)₂(ArN)MoCH-SiPhVin-CHMo(NAr)(OR_F3)₂ (2) (Ar = 2,6-C₆H₃; R_F3 = CMe₂CF₃) have been prepared by the reactions of vinyl silicon reagents Me₂Si(CHCH₂)₂ and PhSi(CHCH₂)₃ with known alkylidene compound PhMe₂C-CHMo(NAr)(OR_F3)₂. Complexes 1 and 2 were structurally characterized. Ring opening metathesis polymerization (ROMP) of cyclooctene using compounds 1 and 2 as initiators led to the formation of high molecular weight polyoctenamers with predominant trans-units content in the case of 1 and predominant cis-units content in the case of 2.