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Nickel‐rich layered oxide, LiNixCoyMnzO2 (NCM, x > 0.8), has emerged as a promising cathode material for lithium‐ion batteries due to its high specific capacity and energy density. However, there remains a challenge regarding NCM degradation during cycling, associated with interfacial side reactions and microcrack formation. Herein, a functional poly(norbornene‐co‐norbornene dicarboxylic acid‐co‐heptafluorobutyl norbornene imide) (PNCI)‐based binder system is introduced, with controlled functionalities and monomer compositions, to preserve the structural integrity of NCM. The PNCI binder system incorporates three different norbornene‐derived monomers with distinct functionalities, allowing for multifunctionality, including electro‐chemo‐mechanical stability, strong adhesion, and dispersibility. By systematically adjusting the molar composition of the PNCI binders, the overall binder characteristics are fine‐tuned, optimizing the adhesion and dispersion of electrode components. The optimized PNCI binder, with desired adhesion strength, surface energy, and polarity, plays a crucial role in facilitating the formation of a uniform electrode structure with a high areal mass loading of NCM, ensuring long‐term cycling stability. This study highlights the significance of striking a balance between functionalities and composition in binder systems to achieve high‐performance NCM cathodes. [ABSTRACT FROM AUTHOR]

A central challenge in practically using high‐capacity silicon (Si) as anode materials for lithium‐ion batteries is alleviating significant volume change of Si during cycling. One key to resolving the failure issues of Si is exploiting carefully designed polymer binders exhibiting mechanical robustness to retain the structural integrity of Si electrodes, while concurrently displaying elasticity and toughness to effectively dissipate external stresses exerted by the volume changes of Si. Herein, a highly elastic and tough polymer binder is proposed by interweaving polyacrylic acid (PAA) with poly(urea‐urethane) (PUU) elastomer for Si anodes. By systematically tuning molecular parameters, including molecular weights of hard/soft segments and structures of hard segment components, it is demonstrated that the mechanical properties of polymer binders, such as elasticity, toughness, and stress relaxation ability, strongly affect the cycling performance of Si electrodes. This study provides new insight into the rational design of polymer binders capable of accommodating the volume changes of Si, primarily by judicious modulation of the mechanical properties of polymer binders. [ABSTRACT FROM AUTHOR]

Extracellular matrix (ECM) proteins containing cell‐attachable Arg‐Gly‐Asp (RGD) sequences exhibit variable bridging and non‐bridging in fibronectin‐collagen and laminin‐collagen complexes that can regulate inflammation, tissue repair, and wound healing. In this study, linking molecule‐mediated conjugation of 1D magnetic nanocylinders (MNCs) to material surfaces pre‐decorated with gold nanospheres (GNSs) is performed, thereby yielding RGD‐coated MNCs (RGD‐MNCs) over RGD‐coated GNSs (RGD‐GNSs) in a non‐bridging state. The RGD‐MNCs are drawn closer to the RGD‐GNSs via magnetic field‐mediated compression of the linking molecules to establish the bridging between them. Relative proportion of the RGD‐MNCs to the RGD‐GNSs is optimized to yield effective remote stimulation of integrin binding to variably bridged RGDs similar to that of invariably bridged RGDs used as a control group. Remote manipulation of the RGD bridging facilitates the attachment structure assembly of macrophages that leads to pro‐healing/anti‐inflammatory phenotype acquisition. In contrast, the non‐bridged RGDs inhibited macrophage attachment that acquired pro‐inflammatory phenotypes. The use of various nanomaterials in constructing heterogeneous RGD‐coated materials can further offer various modes in remote switching of RGD bridging and non‐bridging to understand dynamic integrin‐mediated modulation of macrophages that regulate immunomodulatory responses, such as foreign body responses, tissue repair, and wound healing. [ABSTRACT FROM AUTHOR]

In natural microenvironment, various proteins containing adhesive ligands in fibrous and non‐fibrous structures dynamically couple and decouple to regulate stem cell fate. Herein, materials presenting movably couplable ligands are developed by grafting liganded gold nanoparticles (AuNPs) to a substrate followed by flexibly grafting liganded movable linear nanomaterials (MLNs) to the substrate via a long bendable linker, thereby creating a space between the MLNs and the AuNPs in the decoupled state. Magnetic control of the MLNs decreases this space via the bending of the linker to couple the MLNs to the AuNPs. Remote control of ligand coupling stimulates integrin recruitment to the coupled ligands, thereby non‐toxically facilitating the focal adhesion, mechanosensing, and potential differentiation of stem cells, which is suppressed by ligand decoupling. Versatile tuning of size, aspect ratio, distributions, and ligands of the MLNs can help to decipher dynamic ligand‐coupling‐dependent stem cell fate to advance regenerative therapies. [ABSTRACT FROM AUTHOR]

An effective wound management strategy needs accurate assessment of wound status throughout the whole healing process. This can be achieved by examining molecular biomarkers including proteins, DNAs, and RNAs. However, existing methods for quantifying these biomarkers such as immunohistochemistry and quantitative polymerase chain reaction are usually laborious, resource‐intensive, and disruptive. This article reports the development and utilization of mRNA nanosensors (i.e., NanoFlare) that are topically applied on cutaneous wounds to reveal the healing status through targeted and semi‐quantitative examination of the mRNA biomarkers in skin cells. In 2D and 3D in vitro models, the efficacy and efficiency of these nanosensors are demonstrated in revealing the dynamic changes of mRNA biomarkers for different stages of wound development. In mouse models, this platform permits the tracking and identification of wound healing stages and a normal and diabetic wound healing process by wound healing index in real time. [ABSTRACT FROM AUTHOR]

Aim: This study investigated whether prehospital advanced airway management (AAM) is associated with improved survival of out‐of‐hospital cardiac arrest (OHCA) compared with conventional bag–valve–mask (BVM) ventilation. Methods: We investigated the neurologically favorable survival of adult patients with OHCA who underwent BVM or AAM using the Korean Cardiac Arrest Research Consortium (KoCARC), a multicenter OHCA registry of Korea. The differences in clinical characteristics were adjusted by matching or weighting the clinical propensity for use of AAM or by least absolute shrinkage and selection operator (LASSO). The primary outcome was 30‐day survival with neurologically favorable status defined by cerebral performance category 1 or 2. Results: Of the 9,616 patients enrolled (median age = 71 years; 65% male), there were 6,243 AAM and 3,354 BVM patients. In unadjusted analysis, the 30‐day neurologically favorable survival was lower in the AAM group compared with the BVM group (5.5% vs. 10.0%; hazard ratio [HR] = 1.21, 95% confidence interval [CI] = 1.16 to 1.27; all p < 0.001). In propensity score matching–adjusted analysis, these differences were not found (9.6% vs. 10.0%; HR = 0.98, 95% CI = 0.93 to 1.03, p > 0.05). Inverse probability of treatment weighting‐ and LASSO‐adjusted analyses replicated these results. Conclusions: In this nationwide real‐world data analysis of OHCA, the 30‐day neurologically favorable survival did not differ between prehospital AAM and BVM after adjustment for clinical characteristics. [ABSTRACT FROM AUTHOR]

To utilize thermally activated delayed fluorescence (TADF) technology for future displays, it is necessary to develop host materials which harness the full potential of blue TADF emitters. However, no publication has reported such hosts yet. Although the most popular host for blue TADF, bis[2‐(diphenylphosphino)phenyl]ether oxide (DPEPO) guarantees high‐maximum external quantum efficiency (EQEmax) TADF devices, they exhibit very short operational lifetimes. In contrast, long‐lifespan blue TADF devices employing stable hosts such as 3′,5‐di(9H‐carbazol‐9‐yl)‐[1,1′‐biphenyl]‐3‐carbonitrile (mCBP‐CN) exhibit much lower EQEmax than the DPEPO‐employed devices. Here, an elaborative approach for designing host molecules is suggested to achieve simultaneously stable and efficient blue TADF devices. The approach is based on engineering the molecular geometry, ground‐ and excited‐state dipole moments of host molecules. The engineered hosts significantly enhance delayed fluorescence quantum yields of TADF emitters, as stabilizing the charge‐transfer excited states of the TADF emitters and suppressing exciton quenching, and improve the charge balance. Moreover, they exhibit both photochemical and electrochemical stabilities. The best device employing one of the engineered hosts exhibits 79% increase in EQEmax compared to the mCBP‐CN‐employed device, together with 140% and 92‐fold increases in operational lifetime compared to the respective mCBP‐CN‐ and the DPEPO‐based devices. [ABSTRACT FROM AUTHOR]

We present OH observations made in Amazonas, Brazil during the Green Ocean Amazon campaign (GoAmazon2014/5) from February to March of 2014. The average diurnal variation of OH peaked with a midday (10:00–15:00) average of 1.0 × 106 (±0.6 × 106) molecules cm−3. This was substantially lower than previously reported in other tropical forest photochemical environments (2–5 × 106 molecules cm−3) while the simulated OH reactivity was lower. The observational data set was used to constrain a box model to examine how well current photochemical reaction mechanisms can simulate observed OH. We used one near‐explicit mechanism (MCM v3.3.1) and four condensed mechanisms (i.e., RACM2, MOZART‐T1, CB05, CB6r2) to simulate OH. A total of 14 days of analysis shows that all five chemical mechanisms were able to explain the measured OH within instrumental uncertainty of 40% during the campaign in the Amazonian rainforest environment. Future studies are required using more reliable NOx and VOC measurements to further investigate discrepancies in our understanding of the radical chemistry in the tropical rainforest. Key Points: OH observations with a chemical ionization mass spectrometer during the GoAmazon2014/5 study were lower than some previous studiesBox model simulations of OH were carried out with five different chemical mechanismsObserved and model‐predicted OH concentrations agree to within measurement uncertainty of 40% [ABSTRACT FROM AUTHOR]

Background: Ventricular‐arterial coupling is the ratio of arterial elastance to ventricular end‐systolic elastance. Aims: The objective of this study was to determine the clinical implication of intraoperative ventricular‐arterial coupling derived from the pressure‐area relationship using transesophageal echocardiography. Methods: This retrospective study reviewed the medical records of 72 pediatric patients with ventricular septal defects who underwent corrective surgery with cardiopulmonary bypass. The single‐beat modified method was used to assess ventricular‐arterial coupling. Logistic regression analyses were performed to determine the correlation between ventricular‐arterial coupling and early postoperative outcomes, including the maximum vasoactive‐inotropic score, length of mechanical ventilation, and length of hospital stay. Results: Ventricular‐arterial coupling after cardiopulmonary bypass significantly increased (from 1.0 ± 0.4 to 1.4 ± 0.8, p <.001), indicating a disproportionate increase in the arterial elastance index (from 11.5 ± 5.1 to 19.8 ± 7.5 mmHg/cm2/m2, p <.001) compared with the ventricular end‐systolic elastance index (from 13.0 ± 6.9 to 16.9 ± 9.0 mmHg/cm2/m2, p <.001). Logistic regression analyses revealed that high postoperative ventricular‐arterial coupling was independently associated with higher postoperative maximum vasoactive‐inotropic score (>10; odds ratio [OR], 8.04; 95% confidence interval [CI], 1.38–46.85, p =.020), longer postoperative mechanical ventilation (>15 h; OR: 11.00; 95% CI: 1.26–96.45, p =.030), and longer postoperative hospital stay (>7 days; OR: 2.98; 95% CI: 1.04–8.58, p =.043). Conclusions: Ventricular‐arterial coupling can be easily obtained from the intraoperative transesophageal echocardiography in pediatric patients undergoing ventricular septal defects repair. High postoperative ventricular‐arterial coupling is strongly associated with worse early postoperative outcomes. Ventricular‐arterial coupling shows promise as an intraoperative analysis tool that can provide insight into the impact of interventions on cardiovascular performance and identify potential targets for treatment in this population. [ABSTRACT FROM AUTHOR]

Although the organic light‐emitting diode (OLED) has been successfully commercialized, the development of deep‐blue OLEDs with high efficiency and long lifetime remains a challenge. Here, a novel hyperfluorescent OLED that incorporates the Pt(II) complex (PtON7‐dtb) as a phosphorescent sensitizer and a hydrocarbon‐based and multiple resonance‐based fluorophore as an emitter (TBPDP and ν‐DABNA) in the device emissive layer (EML), is proposed. Such an EML system can promote efficient energy transfer from the triplet excited states of the sensitizer to the singlet excited states of the fluorophore, thus significantly improving the efficiency and lifetime of the device. As a result, a deep‐blue hyperfluorescent OLED using a multiple resonance‐based fluorophore (ν‐DABNA) with Commission Internationale de L'Eclairage chromaticity coordinate y below 0.1 is demonstrated, which attains a narrow full width at half maximum of ≈17 nm, fourfold increased maximum current efficiency of 48.9 cd A−1, and 19‐fold improved half‐lifetime of 253.8 h at 1000 cd m−2 compared to a conventional phosphorescent OLED. The findings can lead to better understanding of the hyperfluorescent OLEDs with high performance. [ABSTRACT FROM AUTHOR]

Novel homoleptic cyclometalated Ir(III) complexes are designed to improve their emission dipole orientations in the emitting layer of blue phosphorescent organic light emitting devices. Biphenyl group is introduced into the imidazole of cyclometalated Ir(III) complexes to simultaneously achieve enhanced efficiency and operation lifetime, resulting in one of the best device performances of single‐stacked organic light emitting diodes with 91% emission dipole orientation, 26.3% maximum external quantum efficiency (maximally calculated as 41%), and 169 h lifetime at 1000 cd m−2 (LT80), color coordinate (0.17, 0.30). To elucidate the physical origin of this significant improvements, the orientational and positional distributions of the homoleptic dopants are analyzed with consideration on intermolecular interactions through atomistic modeling of the emitting layer. With the findings, the phosphorescent dopants could be designed in the future to achieve enhanced performance. [ABSTRACT FROM AUTHOR]

This study concerns the development of a well‐defined synthetic route to obtain lignin‐derived multifunctional graft polymers by simple chemical modification and atom‐transfer radical polymerization. By grafting ion‐conducting and cross‐linkable moieties onto the lignin, star‐shaped functional polymers are prepared. Upon cross‐linking under ultraviolet light irradiation, the resulting polymer network exhibits mechanical stability even at high temperature, whereas the chain mobility is maintained despite the cross‐linked structure. Their use as solid polymer electrolytes (SPEs) and binders for all‐solid‐state lithium metal batteries (LMBs) is also evaluated. The lignin‐derived graft polymers provide a facile ion conduction pathway and also efficiently suppress lithium dendrite growth during cycling, thereby attaining excellent cycling performance for the LMB cell compared to that with a conventional liquid electrolyte–Celgard system. [ABSTRACT FROM AUTHOR]

Bimolecular exciton‐quenching processes such as triplet–triplet annihilation (TTA) and triplet–polaron quenching play a central role in phosphorescent organic light‐emitting diode (PhOLED) device performance and are, therefore, an essential component in computational models. However, the experiments necessary to determine microscopic parameters underlying such processes are complex and the interpretation of their results is not straightforward. Here, a multiscale simulation protocol to treat TTA is presented, in which microscopic parameters are computed with ab initio electronic structure methods. With this protocol, virtual photoluminescence experiments are performed on a prototypical PhOLED emission material consisting of 93 wt% of 4,4ʹ,4ʺ‐tris(N‐carbazolyl)triphenylamine and 7 wt% of the green phosphorescent dye fac‐tris(2‐phenylpyridine)iridium. A phenomenological TTA quenching rate of 8.5 × 10−12 cm3 s−1, independent of illumination intensity, is obtained. This value is comparable to experimental results in the low‐intensity limit but differs from experimental rates at higher intensities. This discrepancy is attributed to the difficulties in accounting for fast bimolecular quenching during exciton generation in the interpretation of experimental data. This protocol may aid in the experimental determination of TTA rates, as well as provide an order‐of‐magnitude estimate for device models containing materials for which no experimental data are available. [ABSTRACT FROM AUTHOR]

Advancement in thin-film transistor (TFT) technologies has extended to applications that can withstand extreme bending or folding. The changes of the performances of amorphous-indium-gallium-zinc-oxide (a-IGZO) TFTs on polyimide substrate after application of extreme mechanical bending strain are studied. The TFT designs include mesh and strip patterned source/drain metal lines as well as strip patterned a-IGZO semiconductor layer. The robustness of the a-IGZO TFTs with the strain of 2.17% corresponding to the radius of 0.32 mm is tested and no crack generation even after 60 000 bending cycles is found. The split of source/drain electrodes and semiconductor layer can improve the mechanical bending stability of the TFTs. This can be possible by using conventional TFT manufacturing process so that this technology can be easily applied to build robust TFT array for foldable displays. [ABSTRACT FROM AUTHOR]

Review: 63 refs. [ABSTRACT FROM AUTHOR]