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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]

Three new gold(I) alkynyl complexes (Au-ABTF(0–2)) containing a benzothiazole fluorenyl moiety, with either an organic phosphine or N-heterocyclic carbene as ancillary ligand, have been synthesized and photophysically characterized. All three complexes display highly structured ground-state absorption and luminescence spectra. Dual-luminescence is observed in all three complexes at room temperature in toluene after three freeze–pump–thaw cycles. The phosphine complexes (Au-ABTF(0–1)) exhibit similar photophysics with fluorescent quantum yields ∼0.40, triplet-state quantum yields ∼0.50, and fluorescent lifetimes ∼300 ps. The carbene complex Au-ABTF2 displays different behavior; having a fluorescent quantum yield of 0.23, a triplet-state quantum yield of 0.61, and a fluorescent lifetime near 200 ps, demonstrating that the ancillary ligand alters excited-state dynamics. The compounds exhibit strong (on the order of 105 M−1 cm−1) and positive excited-state absorption in both their singlet and triplet excited states spanning the visible region. Delayed fluorescence resulting from triplet–triplet annihilation is also observed in freeze–pump–thaw deaerated samples of all the complexes in toluene. DFT calculations (both static and time-resolved) agree with the photophysical data where phosphine complexes have slightly larger S1–T2 energy gaps (0.28 eV and 0.26 eV) relative to the carbene complex (0.21 eV). Comparison of the photophysical properties of Au-ABTF(0–2) to previously published dinuclear gold(I) complexes and mononuclear gold(I) aryl complexes bearing the same benzothiazole-2,7-fluorenyl moiety are made. Structure–property relationships regarding ancillary ligand, bridging moiety, and number of metal centers are drawn. [ABSTRACT FROM AUTHOR]

Herein we report three new gold(I) complexes with a benzothiazole-2,7-fluorenyl moiety bound through a gold–carbon σ-bond and either an N-heterocyclic carbene or organophosphine as ancillary ligands. The complexes have been characterized by NMR spectroscopy, X-ray crystallography, high resolution mass spectrometry, elemental analysis, and static and time-resolved optical spectroscopy. These compounds absorb almost strictly in the ultraviolet region and exhibit dual-luminescence following three freeze–pump–thaw cycles in toluene. The selection of the ancillary ligand significantly influences the excited-state dynamics of the complexes. The two phosphine containing complexes have similar fluorescence and phosphorescence quantum yields leading to generation of white light emission. The carbene containing complex exhibits a higher fluorescence quantum yield compared to its phosphorescence quantum yield resulting in a violet emission. Extensive photophysical characterization of these compounds suggests that the phosphine complexes undergo intersystem crossing more efficiently than the carbene complex. This is supported by a three-fold increase in luminescence lifetime, a halving in fluorescence quantum yield, and an increase in intersystem crossing efficiency by 25 percent for the phosphine complexes. Density-functional theory calculations support these observations where the energy gap between the S1 and T2 states for the carbene is roughly twice that of the phosphine complexes. To our knowledge this is the first example of single-component mononuclear gold(I) complexes exhibiting non-excimeric state white light emission, although a similar phenomenon has been realized for gold(III) aryl compounds. Further, the triplet lifetimes of all three complexes are on the order of one ms in freeze–pump–thaw degassed toluene. These molecules also exhibit delayed fluorescence; all of the complexes display diffusion-controlled rate constants for triplet–triplet annihilation. Strong excited-state absorption is observed from the singlet and triplet excited-states in these molecules as well. The singlet states have excited-state extinction coefficients on the order of 1.5 × 105 M−1 cm−1 and the triplet states have excited-state extinction coefficients on the order of 1.0 × 105 M−1 cm−1. [ABSTRACT FROM AUTHOR]

Introduction Catheter-associated urinary tract infections (CAUTI) adversely affect more than 30% of patients in critical care hospital settings. Considered one of the most prevalent of nosocomial infections, CAUTI are linked to extended hospital stays, rising health care costs, and increased morbidity and mortality. CAUTI are attributed to prolonged catheter use, contaminated catheter insertion, and improper care and maintenance. Adhering to infection control guidelines is essential in preventing CAUTI in healthcare institutions. To illustrate, nearly 380,000 CAUTIs could be prevented and 9,000 lives saved, annually, with the prevention of CAUTI (Centers for Disease Control and Prevention, 2019). Methods Over the last nine months, our burn team has been working to reduce the CAUTI Standardized Infection Ratio (SIR) and Standardized Utilization Ratio (SUR) in the Burn Center. Efforts to facilitate this reduction include the education of nurses and providers on the indications for placement, replacement, and removal of indwelling urinary catheters. We also developed and assigned a PowerPoint presentation and post-assessment to staff members to educate and measure their understanding of the proper care for patients with urinary catheters in place. The hospital facility's protocol was revised to reflect the specific needs and alternatives for urinary catheters in our burn patient population. The new burn specific protocol now serves as a guideline for the multidisciplinary team during daily rounds to reduce the risk of CAUTI in the Burn Center. Charge Nurses continue regular audits. Results The SIR benchmark for 2019 was 0.774. The SIR for the Burn Center in the third quarter of 2019 was incalculable because the predicted number was less than one. The SIR for the fourth quarter of 2019 was 0.913. The SUR benchmark for 2019 was 1. The SUR for the Burn Center in the third and fourth quarters of 2019 were 1.035 and 1.150, respectively. This data indicated the need for a comprehensive plan for improvement. Following the implementation of our team's comprehensive improvement plan, the SIR and number of infections for the first quarter of 2020 was zero, which is below the SIR benchmark 0.727 for 2020. The improvement plan we instituted also reduced the SUR to 0.897 for the first quarter of 2020, compared to the benchmark of one for 2020. The SUR rate for the second quarter was 1.118. Conclusions Instituting this simple nurse-driven protocol has resulted in a noteworthy improvement in patient outcomes. Achieving benchmark goals remains a significant priority to our burn center team as we continue to see the progress and health benefits of fostering the safest care environment for our patients, while remaining financially responsible to our institution. [ABSTRACT FROM AUTHOR]

In an effort to probe the influence of structural isomerism on the excited-state properties of a naphthalene-based donor-acceptor (D-A) system, four 1-naphthalenecarbonitrile compounds with amine substituents in the 2-, 3-, and 4-positions were synthesized and their photophysical properties were examined. Specifically, the molecules 2-dimethylamino-1-naphthalenecarbonitrile ( 2DA ), 2-(1-piperidinyl)-1-naphthalenecarbonitrile ( 2P ), 3-dimethylamino-1-naphthalenecarbonitrile ( 3DA ), and 4-(1-piperidinyl)-1-naphthalenecarbonitrile ( 4P ) were studied. The substitution position of the amine donor has a significant impact on both the ground-state absorption and excited-state properties of the complexes in toluene solution. The energy, band shape, and extinction coefficient of the ground-state absorption spectra are highly dependent on the substitution position of the amine donor. All of the derivatives exhibit fluorescence at room temperature. The fluorescence observed from 2DA, 2P, and 3DA demonstrates a vibronic structure with all three molecules possessing Stokes shifts on the order of 40 nm, whereas the fluorescence observed from 4P is broad and has a Stokes shift 2 times greater than the other derivatives. The fluorescence lifetimes, fluorescence quantum yields, and intersystem crossing quantum yields vary greatly with the substitution position of the amine donor. 2DA and 2P display intermediate fluorescence lifetimes (2.7 ns) and fluorescence quantum yields (0.20) while possessing the greatest intersystem quantum yield (0.80). 3DA has a much greater fluorescence lifetime (16.9 ns) and fluorescence quantum yield (0.82) at the expense of the intersystem crossing quantum yield (0.12). 4P has the shortest lifetime (0.53 ns), with the lowest fluorescence and intersystem crossing quantum yields (<0.05). The singlet-triplet energy gaps are nearly identical for 2DA, 2P, and 3DA with values on the order of 0.70 eV. This singlet-triplet gap is larger in 4P, with a calculated value of 0.94 eV. The triplet-triplet absorption spectra of 2DA, 2P, and 3DA are similar. Broad peaks in the UV and visible regions with maxima around 330 and 500 nm characterize all three spectra. The triplet excited-state extinction coefficient values for 3DA were found to be 1.5 times larger than those in 2DA and 2P. The triplet-triplet absorption spectrum of 4P is markedly different from the triplet-triplet absorption spectra of the other derivatives. The spectrum is broad, with the four local maxima observed at 374, 445, 624, and 774 nm. All four molecules display delayed fluorescence and laser-power-dependent triplet excited-state decay kinetics, indicating the involvement of triplet-triplet annihilation in the deactivation of the triplet excited states. Both the intrinsic triplet lifetimes and triplet-triplet annihilation rate constants were determined. These values are similar for all of the derivatives with triplet lifetimes on the order of 100 μs and diffusion-controlled rates of triplet-triplet annihilation.