Resistance training enhances the stability of sensorimotor coordination

Strategics for the control of human movement are constrained by the neuroanatomical characteristics of the motor system. In particular, there is evidence that the capacity of muscles for producing force has a strong influence on the stability of coordination in certain movement tasks. In the present experiment, our aim was to determine whether physiological adaptations that cause relatively long-lasting changes in the ability of muscles to produce force can influence the stability of coordination in a systematic manner. We assessed the effects of resistance training on the performance of a difficult coordination task that required participants to synchronize or syncopate movements of their index finger with an auditory metronome. Our results revealed that training that increased isometric finger strength also enhanced the stability of movement coordination. These changes were accompanied by alterations in muscle recruitment patterns. In Particular, the trained muscles were recruited in a more consistent fashion following the programme of resistance training. These results indicate that resistance training produces functional adaptations of the neuroanatomical constraints that underlie the control of voluntary movement.

Let your feet do the walking: constraints on the stability of bipedal coordination

In this paper we consider whether the behaviour of the neural circuitry that controls lower limb movements in humans is shaped primarily by the spatiotemporal characteristics of bipedal gait patterns, or by selective pressures that are sensitive to considerations of balance and energetics. During the course of normal locomotion, the full dynamics of the neural circuitry are masked by the inertial properties of the limbs. In the present study, participants executed bipedal movements in conditions in which their feet were either unloaded or subject to additional inertial loads. Two patterns of rhythmic coordination were examined. In the in-phase mode, participants were required to flex their ankles and extend their ankles in synchrony. In the out-of-phase mode, the participants flexed one ankle while extending the other and vice versa. The frequency of movement was increased systematically throughout each experimental trial. All participants were able to maintain both the in-phase and the out-of-phase mode of coordination, to the point at which they could no longer increase their frequency of movement. Transitions between the two modes were not observed, and the stability of the out-of-phase and in-phase modes of coordination was equivalent at all movement frequencies. These findings indicate that, in humans, the behaviour of the neural circuitry underlying coordinated movements of the lower limbs is not constrained strongly by the spatiotemporal symmetries of bipedal gait patterns.

Mono- and dimethyl-1,2,4-triazolate as ligands for the mercuric ion in the cationic three-dimensional coordination polymer of [Hg-2(Mmt)(Dmt)(2)](NO3)(H2O))

Colourless crystals of [Hg-2(Mmt)(Dmt)(2)](NO3)(H2O) were obtained from a reaction of mercuric nitrate with nionomethyl- and dimethyl-1,2.4-triazolate (Mmt(-) and Dmt(-), respectively). In the crystal structure (monoclinic, C2/c (no. 15), a = 2579.4(4) b = 1231.1(2), c = 1634.8(2) pm, beta = 128.32(1)degrees V = 4073.3(11).10(6).pm(3): Z = 8, R-1 [I-0 > 2 sigma(I-0)]: 0.0355), half of the mercuric ions are essentially two-coordinate (Hg-N: 210-215 pm), the other half are tetrahedrally surrounded by N-donor atoms (Hg-N: 221, 225 pm) of the Mmt(-) and Dmt(-) anions. These three-N ligands construct a three-dimensional framework.

Species distribution and coordination of uranyl chloro complexes in acetonitrile

The complex formation of the uranyl ion, UO22+, with chloride ions in acetonitrile has been investigated by factor analysis of UV-vis absorption and U L-3 edge EXAFS (extended X-ray absorption fine structure) spectra. As a function of increasing [Cl-]/[UO22+] ratio, the five monomeric species [UO2(H2O)(5)](2+), [UO2Cl(H2O)(2)(MeCN)(2)](+), [UO2Cl2(H2O)(MeCN)(2)], [UO2Cl3(MeCN)(2)](-), and [UO2Cl4](2-) have been observed. The distances determined in the first coordination sphere are: U-O-ax = 1.77 angstrom, U-O-H2O = 2.43 angstrom, U-N-MeCN = 2.53 angstrom, and U-Cl = 2.68 angstrom. A crystalline material has been obtained from the intermediate solution with the [Cl-]/[UO22+] ratio of similar to 2, where [UO2Cl2(H2O)(MeCN)(2)] is the dominating species. The crystal structure analysis of this material revealed a tetrameric complex, [(UO2)(4)(mu(2)-Cl)(4)(mu(3)-O)(2)(H2O)(2)(CH3CN)(4)]center dot(CH3CN). The crystal data are: monoclinic, space group P2(1)/n, a 10.6388(5) angstrom, b = 14.8441(5) angstrom, c = 10.8521(5) angstrom, beta = 109.164(5)degrees, and Z = 2. The U(VI) coordination of the solution species [UO2Cl2(H2O)(MeCN)(2)] changes during the crystallization by replacing one MeCN molecule with a bridging mu(3)-O atom in the tetramer.

The Open Method of Coordination on Health Care After the Lisbon Strategy II: Towards a Neoliberal Framing?

This paper undertakes a content analysis of the discourse on the Open Method of Coordination on Health Care (OMC/HC) in order to show how equity and solidarity are increasingly linked to optimisation and, as such, how neoliberalism increasingly frames health care. Some of the side-effects of this reframing for politics are highlighted: legitimating and extending EU governance, reducing the space for oppositional formations and limited citizenship. The analysis begins by interrogating the broader context of the Lisbon Strategy II, after which the techniques of the OMC/HC and its substantive outputs are analysed.

Bimanual coordination in chronic schizophrenia

Anomalies of movement are observed both clinically and experimentally in schizophrenia. While the basal ganglia have been implicated in its pathogenesis, the nature of such involvement is equivocal. The basal ganglia may be involved in bimanual coordination through their input to the supplementary motor area (SMA). While a neglected area of study in schizophrenia. a bimanual movement task may provide a means of assessing the functional integrity of the motor circuit. Twelve patients with chronic schizophrenia and 12 matched control participants performed a bimanual movement task on a set of vertically mounted cranks at different speeds (1 and 2 Hz) and phase relationships. Participants performed in-phase movements (hands separated by 0 degrees) and out-of-phase movements (hands separated by 180 degrees) at both speeds with an external cue on or off. All participants performed the in-phase movements well. irrespective of speed or cueing conditions. Patients with schizophrenia were unable to perform the out-of-phase movements, particularly at the faster speed, reverting instead to the in-phase movement. There was no effect of external cueing on any of the movement conditions. These results suggest a specific problem of bimanual coordination indicative of SMA dysfunction per se and/or faulty callosal integration. A disturbance in the ability to switch attention during the out-of-phase task may also be involved. (C) 2001 Academic Press.

The VLT-FLAMES survey of massive stars: constraints on stellar evolution from the chemical compositions of rapidly rotating Galactic and Magellanic Cloud B-type stars

Aims. We have previously analysed the spectra of 135 early B-type stars in the Large Magellanic Cloud (LMC) and found several groups of stars that have chemical compositions that conflict with the theory of rotational mixing. Here we extend this study to Galactic and Small Magellanic Cloud (SMC) metallicities.

Coordination environment of [UO2Br4](2-) in ionic liquids and crystal structure of [Bmim](2)[UO2Br4]

The complex formed by the reaction of the uranyl ion, UO22+, with bromide ions in the ionic liquids 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([Bmiml[Tf2N]) and methyl-tributylammonium bis(trifluoromethylsulfonyl)imide ([MeBu3N][Tf2N]) has been investigated by UV-Vis and U L-III-edge EXAFS spectroscopy and compared to the crystal structure of [Bmim](2)[UO2Br4]. The solid state reveals a classical tetragonal bipyramid geometry for [UO2Br4](2-) with hydrogen bonds between the Bmim(+) and the coordinated bromides. The UV-Vis spectroscopy reveals the quantitative formation of [UO2Br4](2-) when a stoichiometric amount of bromide ions is added to UO2(CF3SO3)(2) in both Tf2N-based ionic liquids. The absorption spectrum also suggests a D-4h symmetry for [UO2Br4](2-) in ionic liquids, as previously observed for the [UO2Cl4](2-) congener. EXAFS analysis supports this conclusion and demonstrates that the [UO2Br4](2-) coordination polyhedron is maintained in the ionic liquids without any coordinating solvent or water molecules. The mean U-O and U-Br distances in the solutions, determined by EXAFS, are, respectively, 1.766(2) and 2.821(2)angstrom in [Bmim][Tf2N], and, respectively, 1.768(2) and 2.827(2) angstrom, in [MeBu3N][Tf2N]. Similar results are obtained in both ionic liquids indicating no significant influence of the ionic liquid cation either on the complexation reaction or on the structure of the uranyl species. (C) 2009 Elsevier Ltd. All rights reserved.

Artificial gravity reveals that economy of action determines the stability of sensorimotor coordination.

Background
When we move along in time with a piece of music, we synchronise the downward phase of our gesture with the beat. While it is easy to demonstrate this tendency, there is considerable debate as to its neural origins. It may have a structural basis, whereby the gravitational field acts as an orientation reference that biases the formulation of motor commands. Alternatively, it may be functional, and related to the economy with which motion assisted by gravity can be generated by the motor system.
Methodology/Principal Findings
We used a robotic system to generate a mathematical model of the gravitational forces acting upon the hand, and then to reverse the effect of gravity, and invert the weight of the limb. In these circumstances, patterns of coordination in which the upward phase of rhythmic hand movements coincided with the beat of a metronome were more stable than those in which downward movements were made on the beat. When a normal gravitational force was present, movements made down-on-the-beat were more stable than those made up-on-the-beat.
Conclusions/Significance
The ubiquitous tendency to make a downward movement on a musical beat arises not from the perception of gravity, but as a result of the economy of action that derives from its exploitation.

Dissociative Recombination of Protonated Formic Acid: Implications for Molecular Cloud and Cometary Chemistry

At the heavy ion storage ring CRYRING in Stockholm, Sweden, we have investigated the dissociative recombination of DCOOD2+ at low relative kinetic energies, from ~1 meV to 1 eV. The thermal rate coefficient has been found to follow the expression k(T) = 8.43 × 10-7 (T/300)^-0.78 cm3 s-1 for electron temperatures, T, ranging from ~10 to ~1000 K. The branching fractions of the reaction have been studied at ~2 meV relative kinetic energy. It has been found that ~87% of the reactions involve breaking a bond between heavy atoms. In only 13% of the reactions do the heavy atoms remain in the same product fragment. This puts limits on the gas-phase production of formic acid, observed in both molecular clouds and cometary comae. Using the experimental results in chemical models of the dark cloud, TMC-1, and using the latest release of the UMIST Database for Astrochemistry improves the agreement with observations for the abundance of formic acid. Our results also strengthen the assumption that formic acid is a component of cometary ices.

Hierarchical coordination of periodic genes in the cell cycle of Saccharomyces cerevisiae

Background: Gene networks are a representation of molecular interactions among genes or products thereof and, hence, are forming causal networks. Despite intense studies during the last years most investigations focus so far on inferential methods to reconstruct gene networks from experimental data or on their structural properties, e.g., degree distributions. Their structural analysis to gain functional insights into organizational principles of, e.g., pathways remains so far under appreciated.