Simultaneous Coordination Research Articles

Two mixed-ligand cadmium(ii) compounds bearing 5-nitrosopyrimidine and N-donor aromatic blocks: self-assembly generation, structural and topological features, DFT studies, and Hirshfeld surface analysis

Using the mixed-ligand strategy, two novel cadmium(II) coordination compounds, namely, the discrete 0D dimer [Cd2(μ2-H2Vi)4(benzim)2]·2MeOH (1) and the 1D coordination polymer [Cd(μ2-DMV)(DMV)(2-apy)]n (2), were self-assembled in aqueous methanol medium under ambient conditions from the cadmium(II) nitrate–H3Vi/HDMV–benzim/2-apy system {where H3Vi = violuric acid [5-(hydroxyimino)pyrimidine-2,4,6(1H,3H,5H)-trione], benzim = benzimidazole, HDMV = N,N′-dimethylvioluric acid [5-(hydroxyimino)-1,3-dimethylpyrimidine-2,4,6(1H,3H,5H)-trione], and 2-apy = 2-aminopyridine}. Both products were isolated as crystalline solids and were structurally characterized. The violurate ligands adopt a tridentate bridging mode in 1, whereas in 2 simultaneous coordination modes [bis(bidentate) bridging + bidentate] are displayed by dimethylviolurate ligands. The nature of the substituent on the violurate ring and the presence of different N-donor ligands play a role in the generation of distinct products. The crystal structures of 1 and 2 reveal a number of strong intermolecular hydrogen bonds that are responsible for the 0D → 3D (1) or 1D → 2D (2) structure extension, resulting in rather complex H-bonded networks. These networks were topologically classified as underlying nets with the sqc2 and 3,4L18 topologies in 1 and 2, respectively. By means of DFT calculations (BP86-D3/def2-TZVPD), the computation of the energetic features of the different noncovalent interactions, such as lone pair (lp)–π, π–π, and C–H/π, was performed aiming at rationalizing their roles in the crystal packing of 1 and 2. Notably, the lp–π interactions observed in 2 present one of the shortest lp–π distances (2.74 A) reported to date. Hirshfeld surface analysis was also carried out to provide qualitative and quantitative insights into the intermolecular interactions in 1 and 2. Furthermore, luminescence properties of the compounds were investigated.

Markov Stability partitioning shows spectrally dependent community structure amongst thalamocortical neural ensembles

The processing of information through the spatiotemporal coordination of neuronal activity is still poorly understood [1]. Here we analyse local field potential (LFP) signals from multi-electrode recordings in the mouse lateral geniculate nucleus (LGN) and visual cortex (V1), to systematically investigate interactions between neuronal ensembles across the frequency spectrum. Computing mutual information for each pair of electrodes using the k-nearest neighbor method developed by [2], two broad groupings can be discerned among the electrodes (Figure ​(Figure1A).1A). The same partitioning is found as a stable solution when applying the Markov Stability algorithm developed by Billeh et. al. [3], which uses a Markov diffusion process through the dataset to detect stable groupings (Figure 1B/C). Analysing narrowband filtered LFP signals, neuronal groupings were found to change between low (1-40 Hz) and high (>40Hz) frequency bands. One particular neural ensemble was found to participate in different groupings across low and high frequency bands, with differing interaction partners and mechanisms as assessed by phase-phase and phase-amplitude correlation measures, both within and across areas. This frequency-specific interaction pattern may allow for the simultaneous coordination of information transmission across different timescales. Figure 1 A. Mutual Information (MI) between the LFP time-series of each of 32 electrodes within mouse LGN. MI is computed with entropy estimates from k-nearest neighbor distances [2]. The diagonal was excluded from analysis. Two broad groupings can be discerned ...

Crystal structure of cyclo-tris-(μ-3,4,5,6-tetra-fluoro-o-phenyl-ene-κ(2) C (1):C (2))trimercury-tetra-cyano-ethyl-ene (1/1).

The title compound, [Hg3(C6F4)3]·C6N4, contains one mol-ecule of tetra-cyano-ethyl-ene B per one mol-ecule of mercury macrocycle A, i.e., A•B, and crystallizes in the monoclinic space group C2/c. Macrocycle A and mol-ecule B both occupy special positions on a twofold rotation axis and the inversion centre, respectively. The supra-molecular unit [A•B] is built by the simultaneous coordination of one of the nitrile N atoms of B to the three mercury atoms of the macrocycle A. The Hg⋯N distances range from 2.990 (4) to 3.030 (4) Å and are very close to those observed in the related adducts of the macrocycle A with other nitrile derivatives. The mol-ecule of B is almost perpendicular to the mean plane of the macrocycle A at the dihedral angle of 88.20 (5)°. The donor-acceptor Hg⋯N inter-actions do not affect the CN bond lengths [1.136 (6) and 1.140 (6) Å]. The trans nitrile group of B coordinates to another macrocycle A, forming an infinite mixed-stack [A•B]∞ architecture toward [101]. The remaining N atoms of two nitrile groups of B are not engaged in any donor-acceptor inter-actions. In the crystal, the mixed stacks are held together by inter-molecular C-F⋯CN secondary inter-actions [2.846 (5)-2.925 (5) Å].

Optimal coordination of distance and directional overcurrent relays considering different network topologies

Most studies in relay coordination have focused solely on coordination of overcurrent relays while distance relays are used as the main protection of transmission lines. Since, simultaneous coordination of these two types of relays can provide a better protection, in this paper, a new approach is proposed for simultaneous coordination of distance and directional overcurrent relays (D&DOCRs). Also, pursued by most of the previously published studies, the settings of D&DOCRs are usually determined based on a main network topology which may result in mis-coordination of relays when changes occur in the network topology. In the proposed method, in order to have a robust coordination, network topology changes are taken into account in the coordination problem. In the new formulation, coordination constraints for different network topologies are added to those of the main topology. A complex nonlinear optimization problem is derived to find the desirable relay settings. Then, the problem is solved using hybridized Genetic Algorithm (GA) with Linear Programming (LP) method (HGA). The proposed method is evaluated using the IEEE 14-bus test system. According to the results, a feasible and robust solution is obtained for D&DOCRs coordination while all constraints, which are due to different network topologies, are satisfied.

Radical Copolymerization Mediated by Unsaturated Metal Sites in Coordination Nanochannels.

Radical copolymerization of methyl methacrylate (MMA) and styrene was performed in [Tb(1,3,5-benzenetrisbenzoate)]n with coordinatively unsaturated metal sites (UMS) immobilized along the one-dimensional nanochannels. A drastic increase in the proportion of MMA units in the resulting copolymers was obtained compared with that obtained from the corresponding solution polymerization systems. Simultaneous coordination of MMA to the UMS is the key to increasing the MMA proportion during the copolymerization in the nanochannels, which was demonstrated by variable temperature IR measurements and several controlled experiments.

Shared performance targets for the horizontal coordination of public organizations: control theory and departmentalism in the United Kingdom’s Public Service Agreement system

Coordinating organizations horizontally is a longstanding difficulty of public governance, often called departmentalism in central government systems. Several tools for horizontal coordination have previously been analysed but shared performance targets across departments have received relatively little attention. This article develops a control theory of shared performance target systems for horizontal coordination of departments consisting of ‘director’ (shared objective and target setting), ‘detector’ (shared monitoring of progress), and ‘effector’ (shared feedback to promote achievement of targets) components. The theory distinguishes between two kinds of shared targets: those promoting sequential coordination and simultaneous coordination among departments. The expectations of control theory are assessed for the Public Service Agreement (PSA) adopted in the United Kingdom. PSAs enabled a step change increase in discussion of shared policy objectives across departments. However, despite these benefits, the fundamentally separate broader ministerial and departmental accountability structures led to the setting of vague outcome targets, underdeveloped performance reporting, and fragmented delivery arrangements for shared targets. Points for practitioners The findings provide a cautionary tale for policy-makers seeking to implement horizontally shared targets across departmental organizations. The UK Government’s Public Service Agreement (PSA) system reveals that shared target systems for departments supervised by a finance ministry are a useful tool for incentivizing departments to collaborate with other departments in policy discussions and resource allocation. However, it was difficult for departments to set specific cross-cutting targets and to develop practical joint delivery and performance reporting strategies across existing departmental boundaries. The effects of the system were, for the most part, counteracted by departmentally focused resource and accountability structures. In some cases, broader structural reform to reorganize departmental structures to align with the formerly cross-cutting policy challenge was necessary rather than predominantly relying on shared targets to pursue policy goals.

Inhibition during response preparation is sensitive to response complexity.

Motor system excitability is transiently suppressed during the preparation of movement. This preparatory inhibition is hypothesized to facilitate response selection and initiation. Given that demands on selection and initiation processes increase with movement complexity, we hypothesized that complexity would influence preparatory inhibition. To test this hypothesis, we probed corticospinal excitability during a delayed-response task in which participants were cued to prepare right- or left-hand movements of varying complexity. Single-pulse transcranial magnetic stimulation was applied over right primary motor cortex to elicit motor evoked potentials (MEPs) from the first dorsal interosseous (FDI) of the left hand. MEP suppression was greater during the preparation of responses involving coordination of the FDI and adductor digiti minimi relative to easier responses involving only the FDI, independent of which hand was cued to respond. In contrast, this increased inhibition was absent when the complex responses required sequential movements of the two muscles. Moreover, complexity did not influence the level of inhibition when the response hand was fixed for the trial block, regardless of whether the complex responses were performed simultaneously or sequentially. These results suggest that preparatory inhibition contributes to response selection, possibly by suppressing extraneous movements when responses involve the simultaneous coordination of multiple effectors.

Modeling and Measurement of Interpersonal Attraction and Coordination in Charged Social Space-Time

A new interpretation of consciousness proposes that states of the mind and behavior may be treated as containing a net electrochemical charge. In the electrodynamic model, interpersonal interactions would exhibit attraction due to complementarily charged states. While this hypothesis remains to be verified with neuroimaging and other techniques, it is important to consider how psychology would in principle be described using charges in social space time. Extended analysis of data from a recently developed method is used to demonstrate how this would occur during optimally coordinated cognitive behavioral activity, or interpersonal “synchronicity.” In an earlier study, pairs of individuals were asked to converse for an initial period, separate, and return to talk again after making a decision about when they were ready to meet for a second conversation with their partner. In addition to the beneficial effects of mindfulness that optimized subsequent interactions, participants with similar personality traits also appeared to be aligned and returned with greater simultaneous coordination. The interaction of pairs in the study may be considered to resemble coupled particles in an EPR experiment, and is used to show how complementary simultaneous coordination can be understood within the context of “charged social space time.” Synchronistic moments of meeting are treated as coherent charge states that converge under effective conditions after an interval of time. The implication is that interpersonal attraction and bonding may create social structures that are uniquely described by fundamental electrodynamic principles. The nature of consciousness and social behavior may require a model using charge like reactions that progress as a function of biophysical energy, space, and time. Here, a method and principles for the development of a practical model of electrodynamic consciousness is detailed.

Cerebral coherence between communicators marks the emergence of meaning.

How can we understand each other during communicative interactions? An influential suggestion holds that communicators are primed by each other's behaviors, with associative mechanisms automatically coordinating the production of communicative signals and the comprehension of their meanings. An alternative suggestion posits that mutual understanding requires shared conceptualizations of a signal's use, i.e., "conceptual pacts" that are abstracted away from specific experiences. Both accounts predict coherent neural dynamics across communicators, aligned either to the occurrence of a signal or to the dynamics of conceptual pacts. Using coherence spectral-density analysis of cerebral activity simultaneously measured in pairs of communicators, this study shows that establishing mutual understanding of novel signals synchronizes cerebral dynamics across communicators' right temporal lobes. This interpersonal cerebral coherence occurred only within pairs with a shared communicative history, and at temporal scales independent from signals' occurrences. These findings favor the notion that meaning emerges from shared conceptualizations of a signal's use.

Hand-Arm Bimanual Intensive Therapy Including Lower Extremities (HABIT-ILE) for Children with Cerebral Palsy

ABSTRACTHand-arm Bimanual Intensive Therapy and Constrained-Induced Movement Therapy have shown evidence of effectiveness in improvement of upper extremity use in children with unilateral spastic cerebral palsy (CP). The effectiveness of interventions that are based on intensive practice of activities that combine UE and LE functions has not been reported. We propose that bimanual UE activities that simultaneously require trunk and LE postural adaptations uniquely address motor control limitations of children with unilateral spastic CP. The aim of this perspective is to present such an approach Hand Arm Bimanual Intensive Therapy Including Lower Extremities (HABIT-ILE). HABIT-ILE is unique in selection of tasks and activities that require simultaneous control and coordination of UE and LE movements. It is a motor-learning-based approach using problem solving and highly structured practice. During the intervention, activities and tasks are progressively graded toward more complex bimanual coordination for the UE and increasing demands of the LE. HABIT-ILE is provided in small groups for 90 hr using a camp model. Future research (randomized controlled trial) is needed to determine the effectiveness of HABIT-ILE.

Bilateral motor tasks involve more brain regions and higher neural activation than unilateral tasks: an fMRI study.

Movements that involve simultaneous coordination of muscles of the right and left lower limbs form a large part of our daily activities (e.g., standing, rising from a chair). This study used functional magnetic resonance imaging to determine which brain areas are used to control coordinated lower-limb movements, specifically comparing regions that are activated during bilateral exertions to those performed unilaterally. Plantarflexor exertions were produced at a target force level of 15% of the participants' maximum voluntary contraction, in three conditions, with their right (dominant) foot, with their left foot, and with both feet simultaneously. A voxel-wise analysis determined which regions were active in the bilateral, but not in the unilateral conditions. In addition, a region of interest (ROI) approach was used to determine differences in the percent signal change (PSC) between the conditions within motor areas. The voxel-wise analysis showed a large number of regions (cortical, subcortical, and cerebellar) that were active during the bilateral condition, but not during either unilateral condition. The ROI analysis showed several motor regions with higher activation in the bilateral condition than unilateral conditions; further, the magnitude of bilateral PSC was more than the sum of the two unilateral conditions in several of these regions. We postulate that the greater levels of activation during bilateral exertions may arise from interhemispheric inhibition, as well as from the greater need for motor coordination (e.g., synchronizing the two limbs to activate together) and visual processing (e.g., monitoring of two visual stimuli).

Comparison and Assessment of a Multiple Optimal Coordinated Design Based on PSS and the STATCOM Device for Damping Power System Oscillations

The aim of this study is to present a comprehensive comparison and assessment of the damping function improvement for the multiple damping stabilizers using the simultaneously coordinated design based on Power System Stabilizer (PSS) and Static synchronous Compensator (STATCOM). In electrical power system, the STATCOM device is used to support bus voltage by compensating reactive power; it is also capable of enhancing the stability of the power system by the adding a supplementary damping stabilizer to the internal AC or DC voltage control channel of the STATCOM inputs to serve as a Power Oscillation Damping (POD) controller. Simultaneous coordination can be performed in different ways. First, the dual-coordinated design between PSS and STATCOM AC-POD stabilizer or DC-POD stabilizer is used. Then, coordination between the AC and DC STATCOM-based POD stabilizers are arranged in a single STATCOM device without PSS. Second, the coordinated design has been extended to triple multiple stabilizers among PSS, the AC-based POD and the DC-based POD in a Single Machine Infinite Bus (SMIB). The parameters of the multiple stabilizers have been tuned in the coordinated design by using a Chaotic Particle Swarm Optimization (CPSO) algorithm that optimized the given eigenvalue-based objective function. The simulation results show that the dual-coordinated design provide satisfactory damping performance over the individual control responses. Furthermore, the-triple coordinated design has been shown to be more effective in damping oscillations than the dual damping stabilizers.

Essential tensions in infant rearing

Essential tensions in infant rearing

Cooperative Anion Recognition in Copper(II) and Zinc(II) Complexes with a Ditopic Tripodal Ligand Containing a Urea Group

The ability of Cu(II) and Zn(II) complexes of the ditopic receptor H2L [1-(2-((bis(pyridin-2-ylmethyl)amino)methyl)phenyl)-3-(3-nitrophenyl)urea] for anion recognition is reported. In the presence of weakly coordinating anions such as ClO4(-), the urea group binds to the metal ion (Cu(II) or Zn(II)) through one of its nitrogen atoms. The study of the interaction of the metal complexes with a variety of anions in DMSO shows that SO4(2-) and Cl(-) bind to the complexes through a cooperative binding involving simultaneous coordination to the metal ion and different hydrogen-bonding interactions with the urea moiety, depending on the shape and size of the anion. On the contrary, single crystal X-ray diffraction studies show that anions such as NO3(-) and PhCO2(-) form 1:2 complexes (metal/anion) where one of the anions coordinates to the metal center and the second one is involved in hydrogen-bonding interaction with the urea group, which is projected away from the metal ion. Spectrophotometric titrations performed for the Cu(II) complex indicate that this system is able to bind a wide range of anions with an affinity sequence: MeCO2(-) ∼ Cl(-) (log K11 > 7) > NO2(-) > H2PO4(-) ∼ Br(-) > HSO4(-) > NO3(-) (log K11 < 2). In contrast to this, the free ligand gives much weaker interactions with these anions. In the presence of basic anions such as MeCO2(-) or F(-), competitive processes associated with the deprotonation of the coordinated N-H group of the urea moiety take place. Thus, N-coordination of the urea unit to the metal ion increases the acidity of one of its N-H groups. DFT calculations performed in DMSO solution are in agreement with both an anion-hydrogen bonding interaction and an anion-metal ion coordination collaborating in the stabilization of the metal salt complexes with tetrahedral anions.

Simultaneous co-ordination of three cytosine ligands displaying different binding sites around the copper centres

The reaction of copper with 1,10-phenanthroline and cytosine forms a novel polymeric structure with two different cytosine binding modes coordinated to copper centers. Also the polymeric complex has mixed coordination geometry around the metal centers.

From molecules to societies: mechanisms regulating swarming behavior in honey bees (Apis spp.)

Reproduction by colony fission, or swarming, is a spectacular example of a behavior that requires the simultaneous coordination of the activities of thousands of honey bee workers and their queen. The successful execution of this collective phenomenon relies on the appropriate response of individuals in swarms to a myriad of signals that are produced by workers and queens to synchronize their nest exodus, subsequent house hunting, and eventual relocation to a new nest site. In this review, we describe our current understanding of the social factors that trigger swarming in colonies and the nonchemical and chemical signals that mediate a coordinated transition between its stages. We also highlight emerging work on the physiological and genomic mechanisms underpinning swarming behavior. Finally, we discuss the possible evolutionary origins of swarming behavior, through comparisons with related behaviors of migration, overwintering, estivation, and diapause in honey bees and other insects.

A conversation with Thomas Südhof

The simple fact that you can understand the words on this page, and that you might remember any of this interview tomorrow, is thanks to the simultaneous and precise coordination of communication between the billions of neurons in your brain and peripheral nervous system. Herein, the JCI speaks with Thomas Sudhof (Figure ​(Figure1)1) of Stanford University, who has been at the center of unlocking the secrets of neurotransmission. His work over the last 30 years has elucidated much of what we know about the molecular mechanisms of neurotransmission in synaptic signaling. For this body of work, Sudhof has recently shared in the 2013 Nobel Prize in Physiology or Medicine and the 2013 Albert Lasker Basic Medical Research Award. The full interview can be seen on the JCI website, http://www.jci.org/kiosk/cgm.

Ultraschall in der interventionellen Schmerztherapie

Peripheral nerve blocks are currently performed relatively blind even in the most complex anatomical structures and physicians mostly rely on palpable anatomical landmarks on the surface. Ultrasound has become an indispensable part of the modern medical world and has long since found its way into almost all medical professions. More and more this trend also reaches interventional pain physicians as it is possible to accurately target structures, to track the needle course during the intervention and to visualize the spread of the local anesthetic. Another advantage compared to other radiological techniques is the profound radiation safety for patients as well as for personnel performing the intervention. A deep understanding of anatomy and its correlate in ultrasound images is one of the most important requirements for the successful use of these interventional techniques. Moreover, the safe performance of the procedure depends on the simultaneous hand-eye coordination. Nevertheless, despite the euphoria ultrasound technology should only be used in pain management with sufficient indications.

An Approximation Algorithm for the Bipartite Traveling Tournament Problem

The bipartite traveling tournament problem (BTTP) is an NP-complete scheduling problem whose solution is a double round-robin inter-league tournament with minimum total travel distance. The 2n-team BTTP is a variant of the well-known traveling salesman problem (TSP), albeit much harder as it involves the simultaneous coordination of 2n teams playing a sequence of home and away games under fixed constraints, rather than a single entity passing through the locations corresponding to the teams' home venues. As the BTTP requires a distance-optimal schedule linking venues in close proximity, we provide an approximation algorithm for the BTTP based on an approximate solution to the corresponding TSP. We prove that our polynomial-time algorithm generates a 2n-team inter-league tournament schedule whose total distance is at most 1 + 2c/3 + (3 − c)/(3n) times the total distance of the optimal BTTP solution, where c is the approximation factor of the TSP. In practice, the actual approximation factor is far better; we provide a specific example by generating a nearly-optimal inter-league tournament for the 30-team National Basketball Association, with total travel distance just 1.06 times the trivial theoretical lower bound.

Spectrophotometric study of kinetics and associated thermodynamics for the complexation of Pr(III) with l-proline in presence of Zn(II)

The complexation of l-proline with Pr(III) has been studied in presence and absence of Zn(II) in different environments by employing 4f–4f absorption transition spectra. The study was carried out through the computation of various spectral parameters namely energy interaction (Slator–Condon (Fk’s), nephelauxetic effect (β), bonding (b1/2) and percent covalency (δ) parameters) and intensity parameters (oscillator strength and Judd–Ofelt parameters). Pr(III), being a paramagnetic shows characteristic 4f–4f transition bands (3H4→3P2, 3P1, 3P0 and 1D2) in the visible region. The intensities of these bands became more prominent in presence of Zn(II) suggesting the evolvement of Zn(II) towards the complexation of Pr(III) and l-proline. This intensification of bands is visualized to be due to the increased probability of interaction between 4f-orbital of metal ion and ligand. As well as these bands have been found to be highly sensitive to even minor changes in the immediate coordination around Pr(III), occurring as a result of the progress of heterobimetallic complexation of l-proline with Pr(III) and Zn(II). The sensitivities of these bands in terms of oscillator strength have been utilized to monitor the simultaneous coordination of l-proline with Pr(III) and Zn(II). The rate of complexation with respect to 4f–4f transition bands has been determined. The determined activation and thermodynamic parameters corresponding to rate constant were found to be highly favourable for the heterobimetallic complexation of l-proline with Pr(III) and Zn(II).