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The electrically‐directed, isothermal response of liquid crystal elastomers (LCEs) to an applied electric field is a compelling approach to realize spatially tailorable, sequence‐controllable, and high‐frequency deformation. The electromechanical response is facilitated by coating aligned LCEs with compliant electrodes. Upon application of an electric field, the electrodes attract and generate Maxwell stress. The directional difference in moduli for aligned LCEs produces directional deformation of the material and does not require mechanical bias or framing. Here, LCEs prepared from a newly reported thiol‐ene reaction are explored as DEAs with improved mechanical and dielectric properties. This report details that incorporating a difunctional liquid crystalline monomer composed of allyl ether functional groups reduces Young's modulus, increases the dielectric constant, and improves cyclic recovery compared to an analogous LCE prepared by thiol‐ene polymerization. Electrically‐induced, isothermal deformation of as much as 30% strain is reported. The facile chemistry and enhanced electromechanical response reported here may enable the functional integration of LCEs in applications such as robotics. [ABSTRACT FROM AUTHOR]

Electrochromic devices have seen widespread adoption in the automotive and aerospace industries and are increasingly considered for applications in the built environment, such as smart windows. Here, a distinctive approach is reported to realizing electrochromism in solid, polymeric materials. The optical elements are based on liquid crystalline elastomers (LCEs) that retain the cholesteric phase (CLCEs). By integrating flexible, optically transparent, and conductive electrodes the CLCEs are actuated as dielectric elastomer actuators. Application of an electric field causes a significant change in the reflection wavelength of fully solid CLCE. The electromechanical response (Maxwell stresses) is reversible. Both uniaxial and biaxial prestrain are shown to enhance and differentiate the stimuli‐response in the photonic device. [ABSTRACT FROM AUTHOR]

Objectives: To test whether providing psychological self-help materials would significantly lower the incidence of post-traumatic stress disorder (PTSD) at 6-12 weeks postnatally.Design: Open-label randomised controlled trial, with blinded outcome assessment.Setting: Community midwifery services in two National Health Service (NHS) trusts in the North West.Sample: A cohort of 2419 women receiving normal NHS postnatal care.Methods: Midwives screened women for traumatic birth experience; 678 women who screened positively (28.1%) were randomly allocated to self-help with usual care (n = 336) or to usual care alone (n = 342). The self-help materials were a leaflet and online film designed to prevent the development of PTSD after trauma exposure through explaining how to manage early psychological responses.Main Outcome Measure: The primary outcome was a composite of diagnostic and subdiagnostic PTSD at 6-12 weeks postnatally using the gold-standard Clinician-Administered PTSD Scale (CAPS-5) interview.Results: Of the 678 women correctly randomised plus the nine women randomised in error, 478 (70.5%) were followed up. Diagnostic or subdiagnostic PTSD rates at follow-up did not differ between groups who received self-help (26.7%, 65/243) or usual care alone (26.2%, 64/244) (intention-to-treat analysis: RR 1.02, 95% CI 0.68-1.53). Findings remained consistent in the per-protocol analysis (RR 1.04, 95% CI 0.85-1.27). Women viewed the materials very positively. There were no adverse effects. Health economic micro-costing indicated implementation would be very low cost.Conclusions: Many women experience a traumatic birth and risk developing PTSD, but self-help strategies without professional support are insufficient and should not be routinely introduced.Tweetable Abstract: Self-help information alone does not reduce the number of women developing PTSD after a traumatic childbirth. [ABSTRACT FROM AUTHOR]

Angelman syndrome (AS) is a rare genetic disorder characterized by severe intellectual disability, seizures, lack of speech, and ataxia. The gene responsible for AS was identified as Ube3a and it encodes for E6AP, an E3 ubiquitin ligase. Currently, there is very little known about E6AP's mechanism of action in vivo or how the lack of this protein in neurons may contribute to the AS phenotype. Elucidating the mechanistic action of E6AP would enhance our understanding of AS and drive current research into new avenues that could lead to novel therapeutic approaches that target E6AP's various functions. To facilitate the study of AS, we have generated a novel rat model in which we deleted the rat Ube3a gene using CRISPR. The AS rat phenotypically mirrors human AS with loss of Ube3a expression in the brain and deficits in motor coordination as well as learning and memory. This model offers a new avenue for the study of AS. Autism Res 2020, 13: 397–409. © 2020 International Society for Autism Research,Wiley Periodicals, Inc. Lay Summary: Angelman syndrome (AS) is a rare genetic disorder characterized by severe intellectual disability, seizures, difficulty speaking, and ataxia. The gene responsible for AS was identified as UBE3A, yet very little is known about its function in vivo or how the lack of this protein in neurons may contribute to the AS phenotype. To facilitate the study of AS, we have generated a novel rat model in which we deleted the rat Ube3a gene using CRISPR. The AS rat mirrors human AS with loss of Ube3a expression in the brain and deficits in motor coordination as well as learning and memory. This model offers a new avenue for the study of AS. [ABSTRACT FROM AUTHOR]

Liquid crystal elastomers (LCEs) are anisotropic polymeric materials. When subjected to an applied stress, liquid crystalline (LC) mesogens within the elastomeric polymer network (re)orient to the loading direction. The (re)orientation during deformation results in nonlinear stress‐strain dependence (referred to as soft elasticity). Here, we uniquely explore mechanotropic phase transitions in elastomers with appreciable mesogenic content and compare these responses to LCEs in the polydomain orientation. The isotropic (amorphous) elastomers undergo significant directional orientation upon loading, evident in strong birefringence and x‐ray diffraction. Functionally, the mechanotropic displacement of the elastomers to load is also nonlinear. However, unlike the analogous polydomain LCE compositions examined here, the isotropic elastomers rapidly recover after deformation. The mechanotropic orientation of the mesogens in these materials increase the toughness of these thiol‐ene photopolymers by nearly 1300 % relative to a chemically similar elastomer prepared from wholly isotropic precursors. [ABSTRACT FROM AUTHOR]

The error-related negativity (ERN) is a negative deflection in the event-related potential that occurs approximately 50ms following the commission of an error at fronto-central electrode sites. Previous models suggest dopamine plays a role in the generation of the ERN. We recorded event-related potentials (ERPs) while 279 children aged 5-7 years completed a simple Go/No-Go task; the ERN was examined in relation to the dopamine D2 receptor ( DRD2) and dopamine transporter ( DAT1) genes. Results suggest an additive effect of the DRD2 and DAT1 genotype on ERN magnitude such that children with at least one DRD2 A1 allele and children with at least one DAT1 9 allele have an increased (i.e. more negative) ERN. These results provide further support for the involvement of dopamine in the generation of the ERN. [ABSTRACT FROM AUTHOR]

Bipolar disorder (BPD) is an often devastating illness characterized by extreme mood dysregulation. Although family, twin and adoption studies consistently indicate a strong genetic component, specific genes that contribute to the illness remain unclear. This study gives an overview of linkage studies of BPD, concluding that the regions with the best evidence for linkage include areas on chromosomes 2p, 4p, 4q, 6q, 8q, 11p, 12q, 13q, 16p, 16q, 18p, 18q, 21q, 22q and Xq. Association studies are summarized, which support a possible role for numerous candidate genes in BPD including COMT, DAT, HTR4, DRD4, DRD2, HTR2A, 5-HTT, the G72/ G30 complex, DISC1, P2RX7, MAOA and BDNF. Animal models related to bipolar illness are also reviewed, with special attention paid to those with clear genetic implications. We conclude with suggestions for strategies that may help clarify the genetic bases of this complex illness. [ABSTRACT FROM AUTHOR]

Keywords: 2-photon direct laser write; liquid crystal elastomers; photocationic polymerization In article number 1903761, Timothy J. White and co-workers employ two-photon polymerization to prepare hybrid micro-patterned actuators from liquid crystal elastomers. 2-photon direct laser write, liquid crystal elastomers, photocationic polymerization. [Extracted from the article]

Liquid crystal elastomers (LCEs) are soft materials that undergo large anisotropic shape change in response to stimuli. Rational organization of the local director field can impart spatial control of the strain profile, enabling stretch‐based deformation capable of nearly 20 J kg−1 of output force. LCEs are increasingly being considered in end‐use applications in robotics, therapeutics, and optics. Here, a new synthetic approach is introduced to prepare LCEs composed of main chain mesogens via the cationic photopolymerization of the epoxy liquid crystal monomer (LCM). This examination details the optical, mechanical, and thermal properties of epoxide‐based LCEs as a function of spacer length (3, 6, or 11 carbons). The oxygen insensitivity of the cationic photopolymerization of these monomers makes this approach particularly attractive for implementation with emerging additive manufacturing techniques. This contribution focuses on microstructuring LCEs via 2‐photon direct laser writing (2P‐DLW). A custom heated cell facilitated 2P‐DLW of the aligned LCE epoxy resin melts to fabricate diverse geometric arrays. Enabled by the orthogonality of the reaction chemistry, hybrid and microstructured material compositions are prepared via the encapsulation of LCE epoxy micropatterns with free‐radical polymerization of acrylate‐based LCEs. The distinct thermomechanical response of the hybridized and microstructured LCE composites enables local and spatially controlled actuation. [ABSTRACT FROM AUTHOR]

Keywords: Festigkeit; Flüssigkristalle; Flüssigkristall-Elastomere; Gummielastizität; Photopolymerisation Unter Belastung orientieren sich die Flüssigkristalle mit den aufgebrachten Spannungstensoren neu, was zu einer signifikanten Verfestigung unter Beibehaltung der schnellen elastischen Erholung führt. Festigkeit, Flüssigkristalle, Flüssigkristall-Elastomere, Gummielastizität, Photopolymerisation. [Extracted from the article]

Objectives: To test whether providing psychological self-help materials would significantly lower the incidence of post-traumatic stress disorder (PTSD) at 6-12 weeks postnatally., Design: Open-label randomised controlled trial, with blinded outcome assessment., Setting: Community midwifery services in two National Health Service (NHS) trusts in the North West., Sample: A cohort of 2419 women receiving normal NHS postnatal care., Methods: Midwives screened women for traumatic birth experience; 678 women who screened positively (28.1%) were randomly allocated to self-help with usual care (n = 336) or to usual care alone (n = 342). The self-help materials were a leaflet and online film designed to prevent the development of PTSD after trauma exposure through explaining how to manage early psychological responses., Main Outcome Measure: The primary outcome was a composite of diagnostic and subdiagnostic PTSD at 6-12 weeks postnatally using the gold-standard Clinician-Administered PTSD Scale (CAPS-5) interview., Results: Of the 678 women correctly randomised plus the nine women randomised in error, 478 (70.5%) were followed up. Diagnostic or subdiagnostic PTSD rates at follow-up did not differ between groups who received self-help (26.7%, 65/243) or usual care alone (26.2%, 64/244) (intention-to-treat analysis: RR 1.02, 95% CI 0.68-1.53). Findings remained consistent in the per-protocol analysis (RR 1.04, 95% CI 0.85-1.27). Women viewed the materials very positively. There were no adverse effects. Health economic micro-costing indicated implementation would be very low cost., Conclusions: Many women experience a traumatic birth and risk developing PTSD, but self-help strategies without professional support are insufficient and should not be routinely introduced., Tweetable Abstract: Self-help information alone does not reduce the number of women developing PTSD after a traumatic childbirth., (© 2020 Royal College of Obstetricians and Gynaecologists.)