Energy Transfer into Period-Tripled States in Coupled Electromechanical Modes at Internal Resonance

Efficient energy transfer often occurs between oscillation modes in a resonator when they are tuned to internal resonance. We design the eigenfrequencies of two vibrational modes of an electromechanical resonator to be close to a ratio of 3:1 and demonstrate that the energy supplied to the upper mode can be controllably transferred to the lower mode. With the lower mode vibrating with a period tripled that of the upper mode, the discrete time-translation symmetry imposed by the periodic drive is broken. The lower mode settles into one of three stable period-tripled states with different phases. This channel for energy transfer from the upper mode can be turned on or off without changing system parameters. When the upper mode itself becomes multistable under strong resonant or parametric drive, additional sets of coexisting period-tripled states emerge in the lower mode. In the latter case, we measure a total of 6 coexisting vibration states with identical amplitude but phases differing by $\pi$/3. Excitation of coexisting states with three different phases could open new opportunities in designing mechanical memory based on ternary logic. Coupled resonators with period-tripled states can also be used to model complex interacting systems with spin equals one

Provision of economic security by creating innovation network of transnational cluster initiatives

The article is devoted to the study of perspectives of creating innovational network of transnational cluster initiatives for provision of economic security of modern economic systems. The authors determine the notion of transnational cluster initiatives and allocate their peculiar features as compared to traditional clusters. The authors analyze statistical information about economic security of developed and developing countries of the world and build a model of economic security of modern economic system before and after creation of innovational network of transnational cluster initiatives. The advantage of forming transnational clusters for national economy consists in expansion of international innovational and technological cooperation and use of world practice of commercialization of technologies which covers the whole innovational cycle – from fundamental research to realization of final products in the world market, including marketing of science-intensive goods and services.peer-reviewe

The Concentration of Zn, Fe, Mn, Cu and Se in Fiber Fractions of Legumes in Indonesia

This study was carried out to evaluate concentration of micro minerals (Zn, Fe, Mn, Cu and Se) of forages and their distribution in fiber fraction (neutral detergent fiber/NDF and acid detergent fiber/ADF) in West Sumatra during dry and rainy seasons. Four species of common legume namely Leucaena leucocephala, Centrocema pubescens, Calopogonium mucunoides and Acacia mangium were collected at native pasture during rainy and dry seasons. The results showed that micro minerals concentration of forages and their distribution in fiber fraction varied among species and season. In general, concentration of micro minerals was slightly higher in rainy season compared to dry season either in legumes forages. Data on legume forages showed that 75% of legumes were deficient in Zn and Mn, 62.5 % deficient in Cu and 50 % deficient in Se. There was no species of legume deficient in Fe. Distribution of micro minerals in NDF and ADF were also significantly affected by species and season and depends on the kinds of element measured. Generally, micro minerals were associated in fiber fractions and it yield much higher during dry season compared to rainy season. Iron (Fe) and selenium (Se) in forages were the highest elements associated in NDF and ADF, while the lowest was found in Copper (Cu). (Animal Production 12(2): 105-110 (2010

Efficiency and mechanism of antitumor activity of cardiolipin-like lipid/thymidine kinase gene HSV-tk lipoplexes in the presence of gancyclovir

The herpes simplex virus thymidine kinase/gancyclovir (HSV-tk/GCV) system is studied as cytotoxic lipoplex based on cardiolipin-like dicationic lipid CDL-I. It is proposed to be used as nonviral gene transfer system in cancer gene therapy protocols. An efficient transfection of MCF7 and HEC293 cell lines with this lipoplex was earlier demonstrated. Non-viral system based on the CDL-I/HSV-tk lipoplex and ganciclovir treatment causes efficiently death of tumor cells with an involvement of apoptosis key stages. It was proved that depolarization of mitochondrial membrane and increased level of NF-kB transcription factor take place as a response to CDL-I/HSV-tk lipoplex action followed by gancyclovir treatment. It suggests an early involvement of apoptosis mitochondrial way to an action of this certain «suicide» system, delivered using dicationic lipid

Transcriptomic changes triggered by ouabain in rat cerebellum granule cells: Role of α3- and α1-Na+,K+-ATPase-mediated signaling

It was shown previously that inhibition of the ubiquitous α1 isoform of Na+,K+-ATPase by ouabain sharply affects gene expression profile via elevation of intracellular [Na+]i/[K+]i ratio. Unlike other cells, neurons are abundant in the α3 isoform of Na+,K+-ATPase, whose affinity in rodents to ouabain is 104-fold higher compared to the α1 isoform. With these sharp differences in mind, we compared transcriptomic changes in rat cerebellum granule cells triggered by inhibition of α1- and α3-Na+,K+-ATPase isoforms. Inhibition of α1- and α3-Na+,K+-ATPase isoforms by 1 mM ouabain resulted in dissipation of transmembrane Na+ and K+ gradients and differential expression of 994 transcripts, whereas selective inhibition of α3-Na+,K+-ATPase isoform by 100 nM ouabain affected expression of 144 transcripts without any impact on the [Na+]i/[K+]i ratio. The list of genes whose expression was affected by 1 mM ouabain by more than 2-fold was abundant in intermediates of intracellular signaling and transcription regulators, including augmented content of Npas4, Fos, Junb, Atf3, and Klf4 mRNAs, whose upregulated expression was demonstrated in neurons subjected to electrical and glutamatergic stimulation. The role [Na+]i/[K+]i-mediated signaling in transcriptomic changes involved in memory formation and storage should be examined further

Gene transfer using new complexes between cardiolipin-like dicationic lipids and plasmid DNA to tumor cells

The lipid vesicles of bisamphiphiles cardiolipin-like dicationic lipids (CDL) I-IV were studied for creation of lipoplexes with plasmid DNA of different sizes to obtain stable lipoplexes for gene transfer to gene therapy. Lipoplexes' sizes (300±100 nm) and stablity (> 2 hrs) of CDL were sufficient to be used in gene transfer against monolayer and suspension cell cultures. The CDL total cytotoxicity determined by MTT-test was lower compare to lipofectin as a control. Transfection conditions against tumor cells lines were optimized by lipoplexes of CDL and plasmid DNA. The most efficient transfection for lipoplexes CDL-plasmid DNA was at the lipid-DNA (L/D) ratio equal to 5 (for lipofectin, it was 2). For monolayer cell cultures, lipoplexes CDL-I are comparable in terms of transfection efficacy with lipofectin; in the case of suspension culture, their efficiency was lower by one order of magnitude. It permits a usage of lipoplexes suggested as mediators for gene transfer and delivery to human tumor cells