Biordered superconductivity and strong pseudogap state

Interrelation between the two-particle and mean-field problems is used to describe the strong pseudogap and superconducting states in cuprates. We present strong pseudogap state as off-diagonal short-range order (ODSRO) originating from quasi-stationary states of the pair of repulsing particles with large total momentum (K - pair). Phase transition from the ODSRO state into the off-diagonal long-range ordered (ODLRO) superconducting state is associated with Bose-Einstein condensation of the K - pairs. A checkerboard spatial order observable in the superconducting state in the cuprates is explained by a rise of the K - pair density wave. A competition between the ODSRO and ODLRO states leads to the phase diagram typical of the cuprates. Biordered superconducting state of coexisting condensates of Cooper pairs with zero momentum and K - pairs explains some properties of the cuprates observed below Tc: Drude optical conductivity, unconventional isotope effect and two-gap quasiparticle spectrum with essentially different energy scales.Comment: 11 pages, 4 fugure

Renewable resources as energy-efficient sources

This article provides the information about the concept of renewable resources as energy-efficient sources, its classification, methods of using, including the most innovative which are realized nowadays. The study offers a comprehensive description of all types of renewable energetic resources, exciting at this moment

"Pair" Fermi contour and repulsion-induced superconductivity in cuprates

The pairing of charge carriers with large pair momentum is considered in connection with high-temperature superconductivity of cuprate compounds. The possibility of pairing arises due to some essential features of quasi-two-dimensional electronic structure of cuprates: (i) The Fermi contour with strong nesting features; (ii) The presence of extended saddle point near the Fermi level; (iii) The existence of some ordered state (for example, antiferromagnetic) close to the superconducting one as a reason for an appearing of "pair" Fermi contour resulting from carrier redistribution in momentum space. In an extended vicinity of the saddle point, momentum space has hyperbolic (pseudoeuclidean) metrics, therefore, the principal values of two-dimensional reciprocal reduced effective mass tensor have unlike signs. Rearrangement of holes in momentum space results in a rise of "pair" Fermi contour which may be defined as zero-energy line for relative motion of the pair. The superconducting gap arises just on this line. Pair Fermi contour formation inside the region of momentum space with hyperbolic metrics results in not only superconducting pairing but in a rise of quasi-stationary state in the relative motion of the pair. Such a state has rather small decay and may be related to the pseudogap regime of underdoped cuprates. It is concluded that the pairing in cuprates may be due to screened Coulomb repulsion. In this case, the superconducting energy gap in hole-doped cuprates exists in the region of hole concentration which is bounded both above and below. The superconducting state with positive condensation energy exists in more narrow range of doping level inside this region. Such hole concentration dependence correlates with typical phase diagram of cuprates.Comment: 23 pages, 11 figures. Submitted to Phys. Rev.

Влияние методов экстракорпоральной детоксикации на уровни заменимых аминокислот в плазме крови у пациентов с сепсисом (Представлено членом-корреспондентом Н.С. Сердюченко)

Some disadvantages of the extracorporeal blood purification (EBP) methods as reducing plasma levels of different important metabolites are described. Disorders of amino acid metabolism in sepsis are manifested into microcirculation interruptions, a decreased immune response and an increased mortality. The aim of the study is to investigate the EBP influence on the levels of nonessential amino acids in the blood plasma of patients with sepsis. 28 patients diagnosed with “sepsis” were selected. Standard treatment protocols of plasma filtration, hemofiltration and hemadsorption with various sorbents were used. A significant decrease in the levels of asparagine, phosphoethanolamine, proline; α-aminobutyric acid showed a significant increase in these levels in patients who underwent “Proteasosorb” sorbent hemadsorption. A significant decrease in the levels of ornithine, aspartic acid, 3-methylhistidine, 1-methylhistidine in patients treated with hemofiltration was found. The EBP methods significantly influence the amino acid metabolism.Недостатком методов экстракорпорального очищения крови (ЭОК) описывается возможное снижение концентрации в плазме крови ряда важных метаболитов. Нарушения обмена аминокислот при сепсисе проявляются расстройствами микроциркуляции, снижением иммунного ответа и увеличением смертности. Цель исследования - изучить влияние ЭОК на динамику уровней заменимых аминокислот в плазме крови у пациентов с сепсисом. Материалы и методы: отобраны 28 пациентов с диагнозом «сепсис», к которым применялись методы гемосорбции с различными сорбентами, плазмафильтрации, гемофильтрации. Результаты. У пациентов после гемосорбции сорбентом «Протеазосорб» установлено достоверное снижение уровней аспарагина, фосфоэтаноламина, пролина; α-аминомасляная кислота продемонстрировала достоверное повышение. У пациентов после гемофильтрации установлено достоверное снижение уровней в плазме орнитина, аспарагиновой кислоты, 3-метилгистидина, 1-метилгистидина. Выводы. Методы ЭОК оказывают значимое влияние на концентрации в плазме некоторых аминокислот

The protein encoded by the germ plasm RNA Germes associates with dynein light chains and functions in Xenopus germline development

Germ plasm plays a prominent role in germline formation in a large number of animal taxons. We previously identified a novel maternal RNA named Germes associated with Xenopus germ plasm. In the present work, we addressed possible involvement of Germes protein in germ plasm function. Expression in oocytes followed by confocal microscopy revealed that the EGFP fused to Germes, in contrast to the free EGFP, co-localized with the germ plasm. Overexpression of intact Germes and Germes lacking both leucine zipper motifs (Germes Delta LZs) resulted in a statistically significant reduction of the number of primordial germ cells (PGCs). Furthermore, the Germes Delta LZs mutant inhibited PGC migration and produced abnormalities in germ plasm intra-cellular distribution at tailbud stages. To begin unraveling biochemical interactions of Germes during embryogenesis, we searched for Germes partners using yeast two-hybrid (YTH) system. Two closely related sequences were identified, encoding Xenopus dynein light chains dlc8a and dlc8b. Tagged versions of Germes and dlc8s co-localize in VERO cells upon transient expression and can be co-immunoprecipitated after injection of the corresponding RNAs in Xenopus embryos, indicating that their interactions occur in vivo. We conclude that Germes is involved in organization and functioning of germ plasm in Xenopus, probably through interaction with motor complexes