Antiferromagnetic spin-coupling between MnII and amminium radical cation ligands: models for coordination polymer magnets

One and two electron oxidation of the manganese(II) complex [L2Mn(hfac)2] {L = 4'',4'''-di-tert-butyl-2',2'',2'''trimethoxy-{4-(4'-diphenylaminophenyl)pyridine} were studied by ultra violet/ visible/ near infra red spectroscopy, cyclic voltammetry and magnetometry. A one-electron oxidation converts the triarylamine ligand to its radical cation and gives a complex in which the antiferromagnetic coupling between the spin on the ligand and that on the metal J/kb is -1.5 K. In a dilute frozen matrix and at low temperature this behaves as an S = 2 system. A two electron oxidation gives [L2Mn(hfac)2]2.+ which at low enough temperatures behaves as an S = 3/2 system but the spin-coupling between the metal and the ligand is weaker (J/kb = -0.3 K). The weakness of these spin-couplings mean that MnII/amminium radical cation complexes are not promising systems on which to base coordination polymer magnets. The equivalent copper(II) complex [L2Cu(hfac)2] was also investigated but this decomposes when an attempt is made to oxidise the ligand to its amminium radical cation

Prediction of the functional properties of ceramic materials from composition using artificial neural networks

We describe the development of artificial neural networks (ANN) for the prediction of the properties of ceramic materials. The ceramics studied here include polycrystalline, inorganic, non-metallic materials and are investigated on the basis of their dielectric and ionic properties. Dielectric materials are of interest in telecommunication applications where they are used in tuning and filtering equipment. Ionic and mixed conductors are the subjects of a concerted effort in the search for new materials that can be incorporated into efficient, clean electrochemical devices of interest in energy production and greenhouse gas reduction applications. Multi-layer perceptron ANNs are trained using the back-propagation algorithm and utilise data obtained from the literature to learn composition-property relationships between the inputs and outputs of the system. The trained networks use compositional information to predict the relative permittivity and oxygen diffusion properties of ceramic materials. The results show that ANNs are able to produce accurate predictions of the properties of these ceramic materials which can be used to develop materials suitable for use in telecommunication and energy production applications

An exploration of UK Paramedics' experiences of Cardiopulmonary resuscitation induced consciousness

Introduction: Consciousness may occur during cardiopulmonary resuscitation despite the absence of a palpable pulse. This phenomenon, known as CPR-Induced Consciousness (CPR-IC) was first described over three decades ago and there has been an increase in case reports describing CPR-IC. However, there remains limited evidence in relation to the incidence of CPR-IC and to practitioners’ experiences of CPR-IC. Methods: A mixed methods, cross-sectional survey of paramedics who were registered with the Health and Care Professions Council (HCPC) and working in the United Kingdom (UK) at the time of the survey. Participants who had experienced CPR-IC were asked to provide details about the number of episodes, a description of how consciousness was manifested, and whether or not it interfered with resuscitation. Results: 293 eligible participants completed the study and 167 (57%) said that they had witnessed CPR-IC. Of those, over 56% reported that they had experienced it on at least two occasions. CPR-IC was deemed to interfere with resuscitation in nearly 50% of first experiences but this fell to around 31% by the third experience. The most common reasons for CPR-IC to interfere with resuscitation were; patient resisting clinical interventions, increased rhythm and pulse checks, distress, confusion and reluctance to perform CPR. Conclusions: The prevalence of CPR-IC in our study was similar to earlier studies; however, unlike the other studies, we did not define what constituted interfering CPR-IC. Our findings suggest that interference may be related as much to the exposure of the clinician to CPR-IC as to any specific characteristic of the phenomenon itself

Awareness of CPR-Induced Consciousness by UK Paramedics

Objectives: Guidelines for the management of hospital cardiac arrest advocate minimally interrupted chest compressions in order to maintain cerebral perfusion pressures and improve the likelihood of a positive outcome. One condition that may lead to interruptions in the delivery of chest compressions is Cardiopulmonary Resuscitation Induced Consciousness (CPR-IC). This study investigates the understanding that UK paramedics have of CPR-IC and how they came by their knowledge. Methods: This study was a cross-sectional survey of paramedics who were registered with the Health and Care Professions Council (HCPC) and practising in the United Kingdom (UK) at the time of the survey. Participants completed an online survey; the first two sections are reported here. Section one asked for demographic data pertinent to the study outcomes and section two asked participants to explain what they understood about CPR-IC and the source of their information. Results: 293 eligible participants completed the survey. Most had over 5-years’ experience as a paramedic and declared no specialist clinical role. Over 50% of respondents said that they had heard of CPR-IC prior to the study and the majority of those provided an explanation that demonstrated some understanding when compared with the definition used by the study team. Over 40% of respondents became aware of CPR-IC having witnessed it in clinical practice. Conclusion: Nearly half of the study population were not aware of CPR-IC and few have had formal training on the phenomenon. There is a clear need for further education on CPR-IC in order for paramedics to better manage CPR-IC when presented with it in practice

People can identify the likely owner of heartbeats by looking at individuals' faces

For more than a century it has been proposed that visceral and vasomotor changes inside the body influence and reflect our experience of the world. For instance, cardiac rhythms (heartbeats and consequent heart rate) reflect psychophysiological processes that underlie our cognition and affective experience. Yet, considering that we usually infer what others do and feel through vision, whether people can identify the most likely owner of a given bodily rhythm by looking at someone's face remains unknown. To address this, we developed a novel two-alternative forced-choice task in which 120 participants watched videos showing two people side by side and visual feedback from one of the individuals' heartbeats in the centre. Participants' task was to select the owner of the depicted heartbeats. Across five experiments, one replication, and supplementary analyses, the results show that: i) humans can judge the most likely owner of a given sequence of heartbeats significantly above chance levels, ii) that performance in such a task decreases when the visual properties of the faces are altered (inverted, masked, static), and iii) that the difference between the heart rates of the individuals portrayed in our 2AFC task seems to contribute to participants' responses. While we did not disambiguate the type of information used by the participants (e.g., knowledge about appearance and health, visual cues from heartbeats), the current work represents the first step to investigate the possible ability to infer or perceive others' cardiac rhythms. Overall, our novel observations and easily adaptable paradigm may generate hypotheses worth examining in the study of human and social cognition

High-frequency peripheral vibration decreases completion time on a number of motor tasks.

A recent theoretical account of motor control proposes that modulation of afferent information plays a role in affecting how readily we can move. Increasing the estimate of uncertainty surrounding the afferent input is a necessary step in being able to move. It has been proposed that an inability to modulate the gain of this sensory information underlies the cardinal symptoms of Parkinson's disease (PD). We aimed to test this theory by modulating the uncertainty of the proprioceptive signal using high-frequency peripheral vibration, to determine the subsequent effect on motor performance. We investigated if this peripheral stimulus might modulate oscillatory activity over the sensorimotor cortex in order to understand the mechanism by which peripheral vibration can change motor performance. We found that 80 Hz peripheral vibration applied to the right wrist of a total of 54 healthy human participants reproducibly improved performance across four separate randomised experiments on a number of motor control tasks (nine-hole peg task, box and block test, reaction time task and finger tapping). Improved performance on all motor tasks (except the amplitude of finger tapping) was also seen for a sample of 18PD patients ON medication. EEG data investigating the effect of vibration on oscillatory activity revealed a significant decrease in beta power (15-30 Hz) over the contralateral sensorimotor cortex at the onset and offset of 80 Hz vibration. This finding is consistent with a novel theoretical account of motor initiation, namely that modulating uncertainty of the proprioceptive afferent signal improves motor performance potentially by gating the incoming sensory signal and allowing for top-down proprioceptive predictions

Relationship between Activity in Human Primary Motor Cortex during Action Observation and the Mirror Neuron System

The attenuation of the beta cortical oscillations during action observation has been interpreted as evidence of a mirror neuron system (MNS) in humans. Here we investigated the modulation of beta cortical oscillations with the viewpoint of an observed action. We asked subjects to observe videos of an actor making a variety of arm movements. We show that when subjects were observing arm movements there was a significant modulation of beta oscillations overlying left and right sensorimotor cortices. This pattern of attenuation was driven by the side of the screen on which the observed movement occurred and not by the hand that was observed moving. These results are discussed in terms of the firing patterns of mirror neurons in F5 which have been reported to have similar properties

Social immunity of the family: parental contributions to a public good modulated by brood size.

Social immunity refers to any immune defence that benefits others, besides the individual that mounts the response. Since contributions to social immunity are known to be personally costly, they are contributions to a public good. However, individuals vary in their contributions to this public good and it is unclear why. Here we investigate whether they are responding to contributions made by others with experiments on burying beetle (Nicrophorus vespilloides) families. In this species, females, males and larvae each contribute to social immunity through the application of antimicrobial exudates upon the carrion breeding resource. We show experimentally that mothers reduce their contributions to social immunity when raising large broods, and test two contrasting hypotheses to explain why. Either mothers are treating social immunity as a public good, investing less in social immunity when their offspring collectively contribute more, or mothers are trading off investment in social immunity with investment in parental care. Overall, our experiments yield no evidence to support the existence of a trade-off between social immunity and other parental care traits: we found no evidence of a trade-off in terms of time allocated to each activity, nor did the relationship between social immunity and brood size change with female condition. Instead, and consistent with predictions from models of public goods games, we found that higher quality mothers contributed more to social immunity. Therefore our results suggest that mothers are playing a public goods game with their offspring to determine their personal contribution to the defence of the carrion breeding resource.AD was supported by NERC grant NE/H019731/1 to RMK. ODeG was supported by the Cambridge Trust and the Mexican Council for Science and Technology (CONACyT). RMK was supported in part by ERC Consolidators grant 310785 BALDWINIAN_BEETLES. SCC was supported by a NERC fellowship (NE/H014225/2), CER was supported by a Department for Employment and Learning PhD studentship. We thank A. Backhouse for help in maintaining the burying beetle population. We thank two anonymous reviewers for helpful comments on the manuscript.This is the final version of the article. It was first available from Springer via http://dx.doi.org/10.1007/s10682-015-9806-

Insight into structure: function relationships in a molecular spin-crossover crystal, from a related weakly cooperative compound

This is a repository copy of Insight into structure: function relationships in a molecular spin-crossover crystal, from a related weakly cooperative compound. White Rose Research Online URL for this paper: http://eprints.whiterose.ac.uk/83008/ Version: Accepted Version Article: Elhaïk, J, Kilner, C and Halcrow, MA (2014) Insight into structure: function relationships in a molecular spin-crossover crystal, from a related weakly cooperative compound. European Journal of Inorganic Chemistry, 2014 (26). 4250 -4253. ISSN 14344250 -4253. ISSN -1948 https://doi.org/10.1002/ejic.201402623 [email protected] https://eprints.whiterose.ac.uk/ Reuse Unless indicated otherwise, fulltext items are protected by copyright with all rights reserved. The copyright exception in section 29 of the Copyright, Designs and Patents Act 1988 allows the making of a single copy solely for the purpose of non-commercial research or private study within the limits of fair dealing. The publisher or other rights-holder may allow further reproduction and re-use of this version -refer to the White Rose Research Online record for this item. Where records identify the publisher as the copyright holder, users can verify any specific terms of use on the publisher's website. Takedown If you consider content in White Rose Research Online to be in breach of UK law, please notify us by emailing [email protected] including the URL of the record and the reason for the withdrawal request. Insight into Compound Jérôme Elhaïk, [a] Colin A. Kilner, [a] and Malcolm A. Halcrow* [a] Abstract: The ClO4 − salt of [FeL2] 2+ (L = 2,6-bis(3-methylpyrazol-1-yl)pyridine) undergoes very gradual thermal spin-crossover centered just below room temperature. In contrast, the BF4 − salt of the same complex exhibits an abrupt and structured spin-transition at lower temperature, with a complicated structural chemistry. The difference can be attributed to a much larger change in molecular structure between the spin states of the complex in the more cooperative BF4 − salt, leading to an increased kinetic barrier for their interconversion. Consistent with that suggestion, the high-spin and low-spin structures of weakly cooperative [FeL2][ClO4]2 are almost superimposable. The continuing interest in thermally and optically switchable spin-crossover (SCO) materials [9] Its thermal spin-transition takes place in two steps, via a re-entrant symmetry-breaking transition to an intermediate crystal phase, with a tripled unit cell containing a mixture of high-spin and low-spin sites. The first of these steps occurs abruptly with hysteresis, but at a temperature that varies according to the water content of the sample (x). In contrast the second step is kinetically slow, and is only achieved when the sample is poised at 100 K for 1.5 hrs. [10] Its excited spin-state trapping (LIESST [11] ) behavior is also unique, in that its thermodynamic high low spin transition and kinetically controlled high low spin-state relaxation exhibit different profiles and are effectively decoupled from each other. [12] Although unexceptional in itself, 1[ClO4]2 provides useful insight into the structural origin of the unusual behavior of the BF4 − salt by providing a rare comparison between strongly and weakly cooperative spin-crossover materials based on the same complex molecule. At 300 K, MT for 1[ClO4]2 is 2.4 cm 3 mol -1 K, lower than expected for a high-spin iron(II) complex with this ligand type (3.4-3.6 cm 3 mol -1 K)