Stratification and filamentation mechanism for a multicharged plasma of a Z-pinch

The thermal-ionizational instability that gives rise to axial and azimuthal inhomogeneities in the electron temperature and electron density in the form of striations and filaments in a multicharged plasma of a Z-pinch is studied in the linear approximation. The theoretical results on the rate at which the inhomogeneities grow and their characteristic spatial dimension agree with the experimental data.     

Correction of venous congestion in abdominal organs under antiorthostatic conditions

The effect of a diuretic on the ultrasound pattern of venous congestion in abdominal organs in a healthy subject staying in an antiorthostatic position (AOP, 15°) for 12 h was studied. After furosemide administration, the circulating plasma volume (CPV), total water content of the body, and extracellular fluid volume decreased more than without the treatment. Overall hypohydration of the body prevented the dilation of hepatic veins typical of an AOP while not affecting noticeably the venous congestion in the portal vein system. In addition, the administration of the diuretic prevented the activation of bile secretion and an increased gastric juice secretion under antiorthostatic conditions. Thus, it was demonstrated that pharmacological hypohydration, by decreasing the CPV and the blood pressure in the inferior vena cava, unloads hepatic veins and prevents enhanced secretion in organs of the digestive system under the conditions of gravitational redistribution of body fluids.     

Syndesmorion gen. nov.—A coenobial alga of Chlorococcalean affinity from the continental Permian-Triassic deposits of Dalongkou section, Xinjiang Province, China

Abundant algal remains, represented by at least five different types of coenobia, have been recovered from continental sediments of the upper lower Guodikeng Formation, from the North Limb of Dalongkou Anticline, Xinjiang Province, China. Some of these forms have been recognized in assemblages from lower Triassic sediments of Poland, Germany, and Australia. The preservation of the Chinese material shows that all these planar, coenobial morphotypes belong to one natural species within the Order Chlorococcales. They are assigned to the genus Syndesmorion gen. nov., type species S. stellatum (Fija?kowska) comb. nov. Algal remains, described as Bijugum by Wood and Turnau in 2001, from the Devonian of Poland are planer and have comparable elongate coenobia but lack star-shaped and reticulate coenobia of Syndesmorion gen. nov. and so the genera are maintained separately.     

The triboluminescent spectra of the blood of gamma-irradiated rats

Triboluminescence (TL) of rat blood 3 h after whole-body single exposure to gamma-radiation (0.25, 1, 3, and 5 Gy) exhibited positive coefficient of correlation r = 0.99 (at a wave length of 412 nm) with radiation dose. The effect of ionizing radiation on the animal body caused changes in blood TL within the fixed areas of the spectral range, whose fluctuation parameters were conditioned by specifically significant radiobiological changes and nonspecific adaptive reactions.     

Excitation of the isomeric states of silver isotope nuclei in the plasma produced by a subrelativistic picosecond laser pulse

Arrangement and results of experiments on the excitation of the (E _m = 93.125 keV, J ^p = 7/2⁺, T _1/2 = 44.3 s) and (E _m = 88.034 keV, J ^p = 7/2⁺, T _1/2 = 39.6 s) isomeric states of Ag¹⁰⁷ and Ag¹⁰⁹ nuclei under the action of X-ray emission in a hot (T _e ∼0.5 keV) dense plasma produced by a laser pulse with the energy ∼9 J, intensity ∼1.2 × 10¹⁸ W/cm², and duration 0.82 ps on the SOKOL-P facility are described. The experimentally determined half-life of the isomeric states agrees satisfactorily with the half-life of the Ag^107m and Ag^109m isomers, and their number N _m ∼ 6.9 × 10⁴ agrees with the qualitative estimate N _m ∼ 2.8 × 10⁴, obtained within the refined model of the physical processes in laser plasma.     

Fossil wood Sequoioxylon dimyense sp. nov. (Cupressaceae) from the upper cretaceous of Zeya-Bureya basin, Russian Far East

A new species Sequoioxylon dimyense (Cupressaceae) is described from the Middle Maastrichtian (Upper Cretaceous) deposits of the Zeya-Bureya basin (Russian Far East) based on the fossil wood anatomy. The new species is characterized by combination of anatomical wood characters of the modern representatives of the subfamily Sequoioideae.     

Analysis of possible causes of activation of gastric and the pancreatic excretory and incretory function after completion of space flight at the international space station

A comparative analysis of the excretory and incretory activity of the stomach and pancreas in astronauts soon after completion of space flights of various durations was performed. An increase in the fasting activity of gastric and pancreatic enzymes and hormones (insulin and C-peptide) in blood, reflecting the increased excretory and incretory activity of organs of the gastroduodenal region developing in microgravity, was demonstrated. The absence of subjects infected with Helicobacter pylori in the space flight crew excluded the involvement of this microorganism in the mechanism underlying the increase in the gastric secretory activity. The absence of correlation between the increase in the secretory activity of organs of the gastroduodenal region and the duration of the space flight allowed us to rule out the hypokinetic mechanism, which is associated with the duration of exposure to microgravity. It was concluded that the main mechanism underlying the changes in the functional state of the digestive system in space flight may be determined by the rearrangement of the venous hemodynamics of organs of the abdominal cavity, unrelated to the duration of exposure to microgravity. It was shown that, after completion of space flights and in ground-based experiments simulating the hemodynamic rearrangement occurring in microgravity, the increase in the basal excretory activity of gastroduodenal organs was not caused by gastrin secretion and occurred simultaneously with an increase in the secretion of insulin, which is considered as a putative hormonal component of the hemodynamic mechanism.     

Low levels of taurine introgression in the current Brazilian Nelore and Gir indicine cattle populations

Background

Nelore and Gir are the two most important indicine cattle breeds for production of beef and milk in Brazil. Historical records state that these breeds were introduced in Brazil from the Indian subcontinent, crossed to local taurine cattle in order to quickly increase the population size, and then backcrossed to the original breeds to recover indicine adaptive and productive traits. Previous investigations based on sparse DNA markers detected taurine admixture in these breeds. High-density genome-wide analyses can provide high-resolution information on the genetic composition of current Nelore and Gir populations, estimate more precisely the levels and nature of taurine introgression, and shed light on their history and the strategies that were used to expand these breeds.

Results

We used the high-density Illumina BovineHD BeadChip with more than 777 K single nucleotide polymorphisms (SNPs) that were reduced to 697 115 after quality control filtering to investigate the structure of Nelore and Gir populations and seven other worldwide populations for comparison. Multidimensional scaling and model-based ancestry estimation clearly separated the indicine, European taurine and African taurine ancestries. The average level of taurine introgression in the autosomal genome of Nelore and Gir breeds was less than 1% but was 9% for the Brahman breed. Analyses based on the mitochondrial SNPs present in the Illumina BovineHD BeadChip did not clearly differentiate taurine and indicine haplotype groupings.

Conclusions

The low level of taurine ancestry observed for both Nelore and Gir breeds confirms the historical records of crossbreeding and supports a strong directional selection against taurine haplotypes via backcrossing. Random sampling in production herds across the country and subsequent genotyping would be useful for a more complete view of the admixture levels in the commercial Nelore and Gir populations.

Electronic supplementary material

The online version of this article (doi:10.1186/s12711-015-0109-5) contains supplementary material, which is available to authorized users.     

Isolation and characteristics of mitochondrial DNA from Acremonium chrysogenum

Circular mDNAs 26.85 and 26.94 kb in length were isolated from two isogenic strains of A. chrysogenum producing cephalosporin C. The strains differed in antibiotic production capacity. Restriction analysis of the mDNAs was performed with using 6 endonucleases. Comparison of the restriction data revealed identity of mDNAs. A restriction map of the mDNAs was constructed. It is useful as a basis for further studies with molecular cloning.     

Evaluating the amino acid CF3-bicyclopentylglycine as a new label for solid-state 19 F-NMR structure analysis of membrane-bound peptides.

The conformation, alignment and dynamic behavior of membrane-bound peptides is readily accessible by solid-state (19)F-NMR spectroscopy, but it has been difficult to incorporate suitable (19)F-labelled amino acids into synthetic peptides. To avoid the drawbacks of previously used labels, we have rationally designed and synthesized a novel amino acid that suits all theoretical and practical requirements for peptide synthesis and subsequent (19)F-NMR structure analysis [Mikhailiuk et. al, Angew. Chem. 2006, 118, 5787-5789]. The enantiomerically pure L-form of 3-(trifluoromethyl)bicyclopent-[1.1.1]-1-ylglycine (CF(3)-Bpg) carries a CF(3) group that is rigidly attached to the peptide backbone and does not racemize during peptide synthesis. It could be demonstrated for several different peptides that their biological activity is usually not affected by a single label, nor the conformation, as monitored by circular dichroism. Here, we carry out a more detailed structure analysis to evaluate the potential and reliability of CF(3)-Bpg for solid-state NMR, using the well-known alpha-helical antimicrobial peptide PGLa as a test case. We have collected several orientational constraints from the anisotropic (19)F--(19)F dipolar couplings of CF(3)-Bpg in various positions of PGLa embedded in lipid bilayers. These resulting structural parameters are then compared with those previously determined from 4-CF(3)-phenylglycine and 3,3,3-d(3)-alanine labels on the same peptide. The analysis confirms that CF(3)-Bpg does not perturb the alpha-helical conformation of PGLa. Likewise, the helix alignment is shown to follow the established concentration-dependent pattern in realigning from a surface-bound S-state to an obliquely tilted T-state. Hence, the advantages of CF(3)-Bpg over all previously used (19)F-labeled side chains are evident, as they combine ease of chemical incorporation and peptide purification with high NMR sensitivity and absent background signals, allowing a straightforward analysis of the dipolar splittings with no need for chemical shift referencing without any ambiguity in the sign of the couplings.