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The energy and velocity distributions of ideal gas particles were first obtained by Boltzmann and Maxwell in the second half of the nineteenth century. In the case of a finite number of particles, the particle energy distribution was obtained by Boltzmann in 1868. However, it appears that this distribution is not valid for all vessels. A round vessel is a special case due to the additional integral of motion, the conservation of the gas angular momentum. This paper is intended to fill this gap, it provides the exact distribution of particle energy for a classical non-rotating ideal gas of a finite number of colliding particles in a round vessel. This previously unknown distribution was obtained analytically from the first principles, it includes the dependence on all the particle masses. The exact mean energies of gas particles are also found to depend on the system parameters, i.e., the distribution of energy over the degrees of freedom is not uniform. Therefore, the usual ideal gas model allows for the uneven energy partitioning, which we study here both theoretically and in simple numerical experiments.

Myotonic dystrophy type 1 (DM1) is an autosomal dominant muscular dystrophy that results from a CTG expansion (50–4000 copies) in the 3′ UTR of the DMPK gene. The disease is classified into four or five somewhat overlapping forms, which incompletely correlate with expansion size in somatic cells of patients. With rare exception, it is affected mothers who transmit the congenital (CDM1) and most severe form of the disease. Why CDM1 is hardly ever transmitted by fathers remains unknown. One model to explain the almost exclusive transmission of CDM1 by affected mothers suggests a selection against hypermethylated large expansions in the germline of male patients. By assessing DNA methylation upstream to the CTG expansion in motile sperm cells of four DM1 patients, together with availability of human embryonic stem cell (hESCs) lines with paternally inherited hypermethylated expansions, we exclude the possibility that DMPK hypermethylation leads to selection against viable sperm cells (as indicated by motility) in DM1 patients.

Purpose. To establish a liquid chromatography/mass spectrometry method to compare the tissue distribution and metabolism of AN1284 after subcutaneous and oral administration at doses causing maximal reductions in IL-6 in plasma and tissues of mice. Methods. Lipopolysaccharide activated RAW 264.7 macrophages were used to detect the anti-inflammatory activity of AN1284 and its metabolites. Mice were given AN1284 by injection or gavage, 15 min before lipopolysaccharide. The reduction of IL-6 measured after 4h. Results. AN1284 is metabolized to the indole (AN1422), a 7-OH derivative and its glucuronide. AN1422 had weaker anti-inflammatory activity than AN1284 in LPS-activated macrophages and in mice. Maximal reductions in IL-6 in plasma, brain and liver were seen after subcutaneous injection of (0.5 mg/kg). This dose was also most effective in reducing IL-6 in the liver after oral drug administration but 2.5 mg/kg was needed for the same reductions in plasma and brain. Peak concentrations after oral administration of AN1284 (2.5 mg/kg) were 5.5-fold higher in the liver but 7-, 11 and 19-fold lower in plasma, brain and kidneys than after injection of 0.5 mg/kg. Similar concentrations in the liver were achieved by AN1284 (1 mg/kg/day) administered in the drinking fluid, and 2.5 mg/kg/day, via subcutaneously-implanted mini-pumps. Although drug levels were only 12% of the peak seen after acute injection of 0.5 mg/kg, they significantly decreased hepatocellular damage, liver triglycerides and cholesterol in diabetic mice. Conclusion. AN1284 can be given orally to treat chronic liver disease and its preferential concentration in the liver should limit potential adverse effects.

We characterized transcriptional responses of potato plants to multiple abiotic stresses and used this information to identify potential mechanisms through which overexpression of the stress related transcription factor CBF1 from Arabidopsis thaliana (AtCBF1) confers multiple stress tolerance. Most transcriptional changes were specific to each condition, but genes involved in phenyl-propanoid biosynthesis were affected by all abiotic stresses evaluated. Interestingly, over-expression of AtCBF1 in potato plants not only conferred tolerance to low temperatures, as previously reported, but also to high-light conditions at 22 °C, suggesting that it confers multiple stress tolerance by enhancing the ability of plants to cope with an excess of radiant energy. Finally, we found that transcriptional changes triggered by abiotic stress were much larger than those resulting from AtCBF1 over-expression in potato, revealing that overexpression of an heterologous transcription factor causes minor alterations in the plant transcriptome in comparison to transcriptional changes triggered by abiotic stresses. Caracterizamos respuestas transcripcionales de plantas de papa a múltiples estreses abióticos y utilizamos esta información para identificar mecanismos potenciales a través de los cuales la sobreexpresión del factor de transcripción CBF1 relacionado con agobio de Arabidopsis thaliana (AtCBF1) confiere tolerancia múltiple al estrés. La mayoría de los cambios transcripcionales fueron específicos para cada condición, pero se afectaron los genes involucrados en la biosíntesis de fenil-propanoides por todos los estreses abióticos evaluados. Interesantemente, la sobreexpresión del AtCBF1 en plantas de papa no solo confirieron tolerancia a bajas temperaturas, como se ha reportado previamente, sino también a condiciones de alta luminosidad a 22 °C, lo que sugiere múltiple tolerancia al estrés mediante el aumento de la habilidad de las plantas para hacer frente a un exceso de energía radiante. Finalmente, encontramos que los cambios transcripcionales disparados por el agobio abiótico fueron mayores que aquellos que resultaron de la sobreexpresión de AtCBF1 en papa, revelando que la sobreexpresión de un factor heterólogo de transcripción causa alteraciones menores en el transcriptoma de la planta en comparación a cambios transcripcionales disparados por estreses abióticos. Fil: Storani, Leonardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas a la Agricultura. Universidad de Buenos Aires. Facultad de Agronomía. Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas a la Agricultura; Argentina Fil: Hernando, Carlos Esteban. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Bioquímicas de Buenos Aires. Fundación Instituto Leloir. Instituto de Investigaciones Bioquímicas de Buenos Aires; Argentina Fil: Staneloni, Roberto Julio. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Bioquímicas de Buenos Aires. Fundación Instituto Leloir. Instituto de Investigaciones Bioquímicas de Buenos Aires; Argentina Fil: Ploschuk, Edmundo Leonardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas a la Agricultura. Universidad de Buenos Aires. Facultad de Agronomía. Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas a la Agricultura; Argentina Fil: Rugnone, Matias Leandro. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas a la Agricultura. Universidad de Buenos Aires. Facultad de Agronomía. Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas a la Agricultura; Argentina Fil: Striker, Gustavo Gabriel. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas a la Agricultura. Universidad de Buenos Aires. Facultad de Agronomía. Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas a la Agricultura; Argentina Fil: Casal, Jorge Jose. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas a la Agricultura. Universidad de Buenos Aires. Facultad de Agronomía. Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas a la Agricultura; Argentina. Fundación Instituto Leloir; Argentina Fil: Chernomoretz, Ariel. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Bioquímicas de Buenos Aires. Fundación Instituto Leloir. Instituto de Investigaciones Bioquímicas de Buenos Aires; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Física; Argentina Fil: Yanovsky, Marcelo Javier. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas a la Agricultura. Universidad de Buenos Aires. Facultad de Agronomía. Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas a la Agricultura; Argentina. Fundación Instituto Leloir; Argentina

In this article, we study dynamics of adsorbate island formation in a model plasma-condensate system numerically. We derive the generalized reaction-diffusion model for adsorptive multilayer system by taking into account anisotropy in transfer of adatoms between neighbor layers induced by electric field. It will be found that with an increase in the electric field strength, a structural transformation from nano-holes inside adsorbate matrix toward separated nano-sized adsorbate islands on a substrate is realized. Dynamics of adsorbate island sizes and corresponding distributions are analyzed in detail. This study provides an insight into details of self-organization of adatoms into nano-sized adsorbate islands in anisotropic multilayer plasma-condensate systems.

Breathing and vigilance are regulated by pH and CO2 levels in the central nervous system. The hypocretin/orexin (Hcrt/Orx)- and histamine (HA)-containing hypothalamic neurons synergistically control different aspects of the waking state. Acidification inhibits firing of most neurons but these two groups in the caudal hypothalamus are excited by hypercapnia and protons, similar to the chemosensory neurons in the brain stem. Activation of hypothalamic wake-on neurons in response to hypercapnia, seen with the c-Fos assay, is supported by patch-clamp recordings in rodent brain slices: Hcrt/Orx and HA neurons are excited by acidification in the physiological range (pH from 7.4 to 7.0). Multiple molecular mechanisms mediate wake-promoting effects of protons in HA neurons in the tuberomamillary nucleus (TMN): among them are acid-sensing ion channels, Na(+),K(+)-ATPase, group I metabotropic glutamate receptors (mGluRI). HA neurons are remarkably sensitive to the mGluRI agonist DHPG (threshold concentration 0.5 µM) and mGluRI antagonists abolish proton-induced excitation of HA neurons. Hcrt/Orx neurons are excited through block of a potassium conductance and release glutamate with their peptides in TMN. The two hypothalamic nuclei and the serotonergic dorsal raphe cooperate toward CO2/acid-induced arousal. Their interactions and molecular mechanisms of H(+)/CO2-induced activation are relevant for the understanding and treatment of respiratory and metabolic disorders related to sleep-waking such as obstructive sleep apnea and sudden infant death syndrome.

We consider the motion of a composite charged particle in a constant electric field. Using the billiard formalism, we establish exact laws of motion for such a particle with a small number of internal degrees of freedom and propose using a generalized Schwarz principle to straighten trajectories in the field presence. Within the billiard formalism, we obtain regimes of motion of a composite particle with two internal degrees of freedom in a constant field.

Genetic ablation of the histamine producing enzyme histidine decarboxylase (HDC) leads to alteration in exploratory behaviour and hippocampus-dependent learning. We investigated how brain histamine deficiency in HDC knockout mice (HDC KO) affects hippocampal excitability, synaptic plasticity, and the expression of histamine receptors. No significant alterations in: basal synaptic transmission, long-term potentiation (LTP) in the Schaffer collateral synapses, histamine-induced transient changes in the CA1 pyramidal cell excitability, and the expression of H1 and H2 receptor mRNAs were found in hippocampal slices from HDC KO mice. However, when compared to WT mice, HDC KO mice demonstrated: 1. a stronger enhancement of LTP by histamine, 2. a stronger impairment of LTP by ammonia, 3. no long-lasting potentiation of population spikes by histamine, 4. a decreased expression of H3 receptor mRNA, and 5. less potentiation of population spikes by H3 receptor agonism. Parallel measurements in the hypothalamic tuberomamillary nucleus, the origin of neuronal histamine, demonstrated an increased expression of H3 receptors in HDC KO mice without any changes in the spontaneous firing of "histaminergic" neurons without histamine and their responses to the H3 receptor agonist (R)-α-methylhistamine. We conclude that the absence of neuronal histamine results in subtle changes in hippocampal synaptic transmission and plasticity associated with alteration in the expression of H3 receptors.

We discuss the interaction between point vortices and point dipole vortices in two-dimensional ideal hydrodynamics and show that the equations of motion of the interacting point and point dipole vortices are exactly integrable. We find exact solutions for all possible parameter values characterizing the vortices and for arbitrary initial conditions and establish the regimes of vortex motion.

By focusing 40-TW, 30-fs laser pulses to the peak intensity of 1019 W/cm2 onto a supersonic He gas jet, we generate quasi-monoenergetic electron beams for plasma density in the specific range 1.5×1019 cm-3≤ne≤3.5×1019 cm-3. We show that the energy, charge, divergence and pointing stability of the beam can be controlled by changing ne, and that higher electron energies and more stable beams are produced for lower densities. The observed variations are explained physically by the interplay among pump depletion and dephasing between accelerated electrons and plasma wave. Two-dimensional particle-in-cell simulations support the explanation by showing the evolution of the laser pulse in plasma and the specifics of electron injection and acceleration. An optimized quasi-monoenergetic beam of over 300 MeV and 10 mrad angular divergence is demonstrated at a plasma density of ne≃1.5×1019 cm-3.

Some distinctive computer technologies, which lead to multiscale computational experiments and investigations of peculiarities of micromechanical behavior of heterogeneous composite media, taking into consideration of atomic-molecular formations, were discussed. The results calculated by Monte-Carlo approach were considered as a perspective method for description of the important features of atomic and molecular texture and energetics of heterogeneous polymer media. The quantum-mechanical approach was discussed as the method for solutions of top problems of micromechanics of polymer composites, namely, an investigation of the interaction of soot model particle with non-terminated and H-terminated surface with segments of polymer chain with different chemical structures. The parallel technologies of calculations and supercomputer were used. Optimization of viscoelastic behavior of composite media such as rubbers leads to the procedure of identification. Validity of reinforcement effect on the basis of the relaxation properties analysis of materials seems very perspective.

A phase frequency changer (PFC) for quasi-optical transmission line with phase sections made of crystal quartz and polarizers executed on the basis of small-period wire gratings has been considered. The PFC is intended for operation in terahertz (THz) frequency region. It has been examined at the frequency f o= 0.89THz. The influence of the differential phase shift deviation in the sections on the output signal spectrum and the influence of the sections mismatch on the reflection signal spectrum have been considered. In the frequency region ± 10% f o the levels of the spurious spectral components of output signal are less than −40 dB with regard to the level of the useful signal of the shifted frequency. The levels of all spectral components of the reflection signal are less than −60 dB with regard to the level of the useful component of the PFC output signal.

Reproductive processes in plants and animals are usually synchronized with favourable seasons of the year. It has been known for 80 years that organisms anticipate seasonal changes by adjusting developmental programmes in response to daylength. Recent studies indicate that plants perceive daylength through the degree of coincidence of light with the expression of CONSTANS, which encodes a clock-regulated transcription factor that controls the expression of floral-inductive genes in a light-dependent manner.

Several mutants with altered phytochrome A (phyA) signalling have been identified in screenings under continuous far-red light (FR). The latter protocol could preclude the identification of mutants affected in the signalling pathway that operates even under transient phyA activation, compared to the high-irradiance response (HIR) pathway that requires continuous FR. Since some photomorphogenic mutants show shoot-height phenotypes, the screening was conducted on dwarf mutants of Arabidopsis thaliana (L.) Heynh. from the ABRC stocks grown under hourly FR pulses. The dwarf mutant cp3 (compacta 3) showed normal hypocotyl length and folded cotyledons in darkness but enhanced hypocotyl-growth inhibition and cotyledon unfolding under pulsed FR. The HIR and the response mediated by phyB were not affected. Under pulsed FR, seed germination and blocking of greening upon transfer to white light were enhanced in cp3. PHYA levels were normal in cp3. The phenotype under pulsed FR but not the adult phenotype required phyA. We propose that CP3 is involved in the negative regulation of the signalling pathway that saturates with transient activation of phyA.

A series of diastereomeric closo-(η1,2-dicyclopentenyl)rhodacarborane complexes with the agostic C--H...Rh bond were synthesized starting from mono-C-substituted anionic nido-carboranes [nido-7-R-7,8-C2B9H11]–. The resulting diastereomeric mixtures were separated into individual isomers by either crystallization or chromatography. The structures and the stereochemistry of the diastereomeric complexes were studied in detail by 1H and 13C NMR spectroscopy. The relative configurations of two key isomers were established by X-ray diffraction analysis. The mechanism of the stereospecific formation of diastereomeric complexes is discussed.

The reaction of OsCl2(PPh3)3 with [nido-7-R1-8-R2-C2B9H10]K+ produced a series of new exo-nido-osmacarborane complexes exo-nido-5,6,10-[Cl(Ph3P)2Os]-5,6,10-(μ-H)3-10-H-7-R1-8-R2-7,8-C2B9H6 (1: R1 = R2 = H; 2: R1 = R2 = Me; 3: R1 = R2 = PhCH2; 4: R1 + R2 = 1,2-C6H4(CH2)2; 5: R1 = H, R2 = Me) in which the osmium-containing group is linked to the nido-carborane ligand through three two-electron three-center bonds. Compounds 1—5 are formed as mixtures of symmetric (a) and asymmetric (b) isomers; pure symmetric isomers 2a and 4a were isolated by fractional crystallization, and the mixture of isomers 3a, was quantitatively separated into individual compounds 3a and 3b by column chromatography on silica gel. Detailed analysis of the 31P{1H}, 1H, 11B NMR spectra of 1a,b—5a,b and 2D 1H-1H{11B} and 11B{1H}-11B{1H} NMR spectra of 3a and 3b was performed. The structures of isomers 2a and 4a were confirmed by an X-ray diffraction study. According to the NMR and X-ray diffraction data, the isomerism of exo-nido-complexes 1a,b—5a,b is actually the cis—trans-isomerism of ligand arrangement in the octahedral coordination of the Os atom.

The reaction of Ru3(CO)12 with 1,3-diferrocenylprop-2-en-1-one,trans-FcCH=CHCOFc (where Fc is ferrocenyl), in boiling hexane afforded the complex Open image in new window (2c), which was converted into Open image in new window (3c) upon further heating. These complexes gave the complex Open image in new window (4) containing two Cl-bridged oxaruthenacycles upon dissolution in CHCl3 or CH2Cl2. The structures of complexes 3 and 4 were established by X-ray diffraction analysis. According to the data of1H NMR spectroscopy, the Cl-bridged complex exists in solutions as a mixture of isomers along with the monomeric form resulting from the cleavage of the halide bridges. All interconversions of the isomers occur with the participation of the monomeric form.

Reaction of the cluster Os3(μ-CO)(CO)9(μ3-η1:η1:η2-Me3SiC2Me) with HC≡CCOOMe in benzene at 70 °C results in Os3(CO)9{μ3-η1:η1:η2:η2-C(SiMe3)C(Me)C(COOMe)CH× (5), Os3(CO)9{μ3-η1:η1:η2:η2-C(SiMe3)C(Me)C(H)C(COOMe)CH× (6), Os3(CO)9{μ-η1:η1:η4-C(SiMe3)C(Me)C(H)C(COOMe)CH× (7), and Os3(CO)δ{μ3-η1:η1:η4:η1-C(SiMe3)C(Me)C(H)C(COOMe)× complexes (8), containing an osmacyclopentadiene moiety. Complexes5–8 were characterized by1H NMR and IR spectroscopy. The structure of clusters5 and8 was confirmed by X-ray analysis. Complex7 is formed from cluster5 as a result of a new intramolecular rearrangement and complex8 is obtained by decarbonylation of compound6. Complex8 adds PPh3 to give Os3(CO)δ(PPh3){μ-η1:η1:η4-C(SiMe3)C(Me)C(H)C(COOMe)×.

The reaction of MeSiCl3 with 3 equivalents of LiC5H4(CO)2Fe(η1,η5-C5H4)Mn(CO)3 afforded the hexanuclear complex MeSi[η1,η5-C5H4(CO)2Fe(η1,η5-C5H5)Mn(CO)3]3. The structure of the resulting complex was established by1H and13C NMR and IR spectroscopy and by X-ray diffraction analysis.

Ruthenium carbonyl triphenylphosphine complexes Ru2(CO)6−n(PPh3)n{μ-C(CH=CHPh)C(Ph)C(CH=CHPh)C(Ph)} (n=1, 2) were obtained by the reaction of complex Ru2(CO)6{μ-C(CH=CHPh)C(Ph)C(CH=CHPh)C(Ph)} containing the ruthenacyclopentadiene moiety with PPh3 in refluxing toluene. The complexes were characterized by IR and by1H,13C, and31P NMR spectroscopy, and by X-ray analysis. The monophosphine derivative is identical to the complex formed by fragmentation of the Ru3(CO)8(PPh3){μ-C(CH=CHPh)C(Ph)C(CH=CHPh)C(Ph)} cluster and contains the PPh3 ligand at the ruthenium atom of the ruthenacyclopentadiene moiety.

9-(α-Ferrocenylethyl)adenine was prepared by the reaction of adenine with α-hydroxyethylferrocene in a two-phase aqueous-organic medium in the presence of HBF4. The structure of the resulting compound was established by X-ray diffraction analysis.

The behavior of the phosphine-phosphine sulfide complexes of silver, [Ph2P(S)(CH2) n PPh2] m ·AgNO3 (n=2 or 4;m=1 or 2), in pyridine was studied. Dissolution of the 1:1 complexes in pyridine leads to destruction of their dimeric structures Ag2[Ph2P(S)(CH2) n PPh2]2(NO3)2 (A) to form the complexes Agpy +−P(Ph2)(CH2) n Ph2P=S and Agpy +−S=PPh2(CH2) n PPh2. The solid complexes isolated from pyridine restore dimeric structure A. According to the data of X-ray diffraction analysis, the 1:2 complex isolated from pyridine has the structure [S=P(Ph2)(CH2)2(Ph2)P−(NO3)Ag(Py)−P(Ph2) (CH2)2(Ph2)P=S]Py. According to the data of IR spectroscopy, dissolution of this complex in chloroform leads to the formation of the dimeric structure Ag2Ph2P(S)(CH2)2PPh2]4(NO3)2.

The reaction of Os3(μ-Cl)2(CO)10 (1) with Ph2PCH2PPh2 (dppm) in a toluene solution at 65°C results in novel osmium complexes [Os3(μ-Cl)2(CO)9]2(dppm) (2) and [Os3(μ-Cl)2(CO)8]2(dppm)2 (3). Compounds 2 and 3 were characterized by1H and31P NMR, and IR spectroscopy and their structures were established by X-ray analysis. In both compounds, dppm is a bridging ligand between the two cluster units. Molecule3 can be considered as an unusual 12-membered macrocycle containing C, P, Cl, and Os atoms in the ring.

Phytochrome action in fully de-etiolated sunlight-grown potato (Solanum tuberosum L.) was studied by comparing wild-type (WT) plants and transgenic plants with either a sense or an anti-sense phytochrome A (phyA) construction. Radial stem growth, anthocyanin levels, and sucrose-phosphate-synthase activity were directly related to the levels of phyA (severely reduced in transgenics with anti-sense phyA, normal in WT and increased in transgenic with sense phyA). In contrast, longitudinal stem growth was inversely related to the levels of phyA. Phytochrome A influenced stem-extension growth responses to red/far-red ratios perceived by stable phytochrome[s]. First, far-red light reflected by non-shading neighbours promoted stem growth in WT plants but transgenic plants with either increased or reduced phyA levels failed to respond to this light signal. Second, plants with low phyA levels also showed impaired sensitivity to reductions in end-of-day red/far-red ratios. In addition, phyA appears to perceive changes in irradiance reaching the stem: lowering the amount of red plus far-red light reaching the stem promoted stem growth in WT plants. This effect was exaggerated in phyA overexpressors and absent in phyA underexpressors. Thus, phyA is active in fully de-etiolated, sunlight-grown plants.

Reactions of the alkyne cluster Os3(μ-CO)(CO)9(μ3-Me3C2Me) with alkynes Me3SiC≡CR (R=Me, Bun) in refluxing hexane result in the formation of clusters Os3(CO)9{μ3-C(SiMe3)=C(Me)C=C(SiMe3)=C(Me)C=C(SiMe3)R} (2a: R=Me;3a: R=Bun). The dienediyl ligand in these complexes is formed by alkyne-vinylidene coupling, with vinylidene generated in the course of reaction from the alkyne molecule by the acetylene-vinylidene rearrangement involving a 1,2-shift of the Me3Si group. The structure of cluster3a was determined by X-ray structural analysis. The dienediyl ligand is coordinated to three metal atoms of the cluster framework by two π-ethylene bonds with two osmium atoms and two σ-bonds with the third osmium atom with the formation of the osmacyclobutene moiety. The1H and13C NMR study of13CO-enriched samples of clusters2a and3a revealed the stereochemical nonrigidity of these molecules due to the exchange of the hydrocarbon and carbonyl ligands.

The reaction of Ru3(CO)12 with tetramethyltrifluoromethylcyclopentadiene at various ratios of the reagents was studied. Refluxing of Ru3(CO)12 with a sixfold excess of tetramethyltrifluoromethylcyclopentadiene in octane in an inert atmosphere gave a complex, which is, according to X-ray diffraction data, a dimer,trans-[Ru(η5-C5Me4CF3)(CO)2]2. The reaction under the same conditions but starting from Ru3(CO)12 and C5Me4CF3H in 2∶1 molar ratio gave a hexaruthenium cluster [Ru6(μ3-H)(η2-μ4-CO)2(μ-CO)(Co)12(η5-C5Me4CF2)], which was characterized by IR as well as1H,13C, and19F NMR spectroscopy. According to X-ray diffraction data, an Ru4 tetrahedron, in which two edges are bound by additional “briding” Ru atoms, constitutes the frame of this compound. This complex has one (η5-C5Me4CF3) ligand, as well as one (μ3-H) and two (η2-μ4-CO) groups.

The complexation reactions of monoaryl- and diaryl-substituted [2.2]paracyclophanes with (NH3)3Cr(CO)3 have been studied. The aromatic rings of [2.2]paracyclophane are more favorable for coordination than aryl substituents. This leads to the regioselective formation of the corresponding mono- or binuclear tricarbonylchromium complexes. In some cases, the tricarbonylchromium group is coordinated to the aryl ring of the substituent to form (in low yields) the corresponding mononuclear complex or binuclear complexes with both the aromatic ring of paracyclophane and the aryl ring of the substituent involved in coordination. The structure of such complex, namely, [4-(η6-2,4,6-trimethylpheny)-11-16-η6-[2,2]paracyclophane]bis[tricarbonylchromium(0)] was confirmed by X-ray diffraction study.

The testing results of a homodyne 0.195-mm laser interferometer-polarimeter based on quasioptical components are presented. The interferometer-polarimeter matched to the multichannel interferometer of a Tokamak-15 machine admits of simultaneous measurements of the plasma electron density and poloidal magnetic field in one of the seven vertical-probing channels without any disturbance in the others. The achieved responce threshold of the electron density is 3.4·1011 cm−3, the polarization resolution and the phase difference measurement error are no worse than 0,10 and ±40, respectively.

The addition of CCl4 to hex-1-ene and to the methyl ester ofN-(trans-cinnamoyl)-l-proline (2) catalyzed by M3(CO)12 or by the M3(CO)12+DMF system (M=Fe, Ru, Os) was studied. The use of ruthenium and osmium dodecacarbonyls in combination with DMF increases the yields of adducts CCl3CH2CHClC4H9 (4) and PhCHClCH(CCl3)C(O)R′ (3) over those obtained in reactions catalyzed by the same carbonyls without DMF. In addition to adduct3, salts [M(CO3)Cl3]−[Me2NH2]+ were isolated from the products of the reaction between CCl4 and1 in the presence of M3(CO)12+DMF (M=Ru, Os). These salts do not catalyze this reaction and apparently result from chain termination. Experimental results in favor of a coordination mechanism of the addition of CCl4 to olefins in the presence of Ru3(CO)12 and Os3(CO)12 were obtained.

The reaction of (carbamoylmethyl)diphenylphosphine sulfide with AgNO3 yields the polymeric complex [Ag2{Ph2P(S)CH2C(O)NH2}2(NO3)2] n . Its structure was established by X-ray diffraction analysis. The coordination environments about both Ag+ cations are formed by five donor atoms, two of which are bonded to the metal atom substantially more weakly than the remaining three atoms. The compositions of the coordination polyhedra are different: ({AgSO′(C)O(N)O2(N′)} and {AgS′ SO(C)O2(N)}). The coordinated ligands differ in their functions: one ligand chelates the metal cation and its sulfur atom is additionally bonded to the second cation, while the second ligand acts as a bridge between the two different cations. The structure of the complex and the character of the interaction between the ligand and AgNO3 are substantially affected by the network of hydrogen bonds.

(N, N-Diethylthiocarbamoylmethyl)diphenylphosphine sulfide, Ph2P(S)CH2C(S)NEt2, forms a distorted tetragonal bisligand complex [AgL2]NO3 with Ag+. The stability constant of the complex in acetonitrile was estimated by spectrophotometry (logK=3.7).

The interaction of stable 2-RSO2-benzonitrile oxides1a−c (R=Ph, But, or PhMeN) with C60 fullerene proceeds at the double (6,6)-bond of fullerene as the [3+2] cycloaddition to form the corresponding isoxazolines2a−c. The molecular structure of compound2b was established by X-ray structural analysis. The interaction of C60 fullerene with 2-(5-methyl-4-nitrothiophene)carbonitrile sulfide, which was obtained by thermolysis of 5-(5′-methyl-4′-nitro-2′-thienyl)1,3,4-oxathiazol-2-one, affords only unstable products.

Tetraphenylantimony hydrogen phthalate, Ph4SbOC(O)C6H4000H-o, was prepared by the reaction of pentaphenylantimony with phthalic acid. According to the data of X-ray structural analysis, the resulting compound is a trigonal-bipyramidal complex of antimony with three phenyl groups in equatorial positions; the fourth phenyl group and the carboxyl fragment are in axial positions. The CSbO angle is 177.5(1)° the Sb-C(Ph)eq and Sb-C(Ph)ax distances are 2.099(4)-2.177(4) A and 2.129(4) A, respectively. The H atom of the free carboxyl group and the carbonyl O atom of another carboxylate group form an intramolecular hydrogen bond.

Unfilled and carbon black-filled samples of synthetic isoprene- and butadiene-methylstyrenebased rubbers were characterized by precise heat capacity measurements in the temperature interval 4.2–300 K. Both unfilled samples proved to behave in an essentially fracton-like way in the temperature interval 6–30 K. The excess thermodynamic quantities derived from the smoothed data suggested that the thermodynamic state of the elastomeric phase in the filled rubbers was intrinsically unstable.

Diyne FcCmCC.CFc (Fc is ferrocenyl) reacts with Ru3(CO)12 in boiling hexane to yield binuclear complexes Ru2 and Ru2(CO)6(C4Fc2(C=CFc)2C=O) containing ruthenacyclopentadiene and diruthenacycloheptadienone rings, respectively. The isomerism of the complexes is due to the different ways of coupling of the alkyne fragments of the diyne, namely, “head-to-head”, “head-to-tail” or “tail-to-tail”. The reaction of enyne PhC=CCH=CHPh with Ru3(CO)12 under similar conditions gives isomeric binuclear complexes Ru2(CO)6(C4Ph2(CH=CHPh)2) and trinuclear clusters Ru3(CO)6(w-CO)2(C4Ph2(CH=CHPh)2) and Ru3(CO)8(μ3-,η1-η1-η4-η2 C4Ph2(CH=CHPh)2). The structure of the latter was determined by X-ray diffraction analysis. The Ru3 triangle coordinates eight terminal CO groups and the organic ligand resulting from the “head-to-head” dimerization of enyne molecules; the ruthenacyclopentadiene moiety is η4-coordinated to the Ru(CO)2 group, and the third ruthenium atom is η2-bound to one of the PhCH=CH groups.

A novel optically active exo-metallofullerene derivative, η2-C60Pt[(+)-DIOP] (1) (DIOP is 2,3-o,o'-isopropylidene-2,3-dihydroxy-1,4-bis(diphenylphosphinobutane)), is formed as a result of the cleavage of the chelate metallocycle in Pt[(+)-DIOP]2 and the substitution of the bidentate (+)-DIOP ligand with C60. Cluster 1 was also obtained by replacement of the phosphine ligands in η2-C60Pt(PPh3)2 by (+)-DIOP. Compound 1 was identified by its electronic absorption spectra,31P NMR spectra, and the elemental analysis data. A singlecrystal X-ray study of the 1 cyclooctene solvate, η2-C60Pt[(+)-DIOP] C8H14 was performed. Packing of the fullerene cores in a crystal of 1 · C8H 14 corresponds to the diamond structure subjected to the significant orthorhombic distortions.

Os3(μ-CO)(CO)9(μ3-Me3SiC2Me) alkyne complexes react with ferrocenylacetylene in hot benzene to form Os3(CO)9{μ3-η1-η1-η2-η2-C(SiMe3)C(Me)C(H)C(Fe)} and a small amount of the isomeric Os3(CO)9(μ-η1-η1-η4-C(SiMe3)C(Me)C(Fc)C(H)} complex. The structure of the major isomer was confirmed by X-ray structural analysis of the single crystal. Thermolysis of this complex in refluxing benzene affords the Os3(μ-H)(CO)8{μ3-η1-η1-η4-η1-C(SiMe3)C(Me)C(H)(C5H3FeC5H5)} complex with theortho-metallated ferrocene moiety. The spectral characteristics of clusters with the μ3-η1-η1-η2-η2 and μ-η1-η1-η4 coordinations of the metallacyclopentadiene fragment have been established, which made it possible to choose between the alternative modes of bonding of diene with the trimetallic core.