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Bipyridine‐based covalent organic frameworks (COFs) have emerged as promising contenders for the photocatalytic generation of hydrogen peroxide (H2O2). However, the presence of imine nitrogen alters the mode of H2O2 generation from an efficient one‐step two‐electron (2e−) route to a two‐step 2e− oxygen reduction pathway. In this work, we introduce 3,3′‐bipyridine units into imine‐based COF skeletons, creating a pyridyl‐imine structure with two adjacent nitrogen atoms between the pyridine ring and imine linkage. This unique bipyridine‐like architecture can effectively suppress the two‐step 2e− ORR process at the single imine‐nitrogen site, facilitating a more efficient one‐step 2e− pathway. Consequently, the optimized pyridyl‐imine COF (PyIm‐COF) exhibits a remarkable H2O2 production rate of up to 5850 μmol h−1 g−1, nearly double that of pristine bipyridine COFs. This work provides valuable insight into the rational design of functionalized COFs for enhanced H2O2 production in photocatalysis. [ABSTRACT FROM AUTHOR]

Aims: Pulmonary congestion (PC) expressed by residual lung ultrasound B‐lines (LUS‐BL) could exist in some discharged heart failure (HF) patients, which is a known determinant of poor outcomes. Detection efficacy for PC is suboptimal with widely used imaging modalities, like X‐ray or echocardiography, while lung ultrasound (LUS) can sufficiently detect PC by visualizing LUS‐BL. In this trial, we sought to evaluate the impact LUS‐BL‐guided intensive HF management post‐discharge on outcome of HF patients discharged with residual LUS‐BL up to 1 year after discharge. IMP‐OUTCOME is a prospective, single‐centre, single‐blinded, randomized cohort study, which is designed to investigate if LUS‐BL‐guided intensive HF management post‐discharge in patients with residual LUS‐BL could improve the clinical outcome up to 1 year after discharge or not. Methods and results: After receiving the standardized treatment of HF according to current guidelines, 318 patients with ≥3 LUS‐BL assessed by LUS within 48 h before discharge will be randomly divided into the conventional HF management group and the LUS‐BL‐guided intensive HF management group at 1:1 ratio. Patient‐related basic clinical data including sex, age, blood chemistry, imaging examination, and drug utilization will be obtained and analysed. LUS‐BL will be assessed at 2 month interval post‐discharge in both groups, but LUS‐BL results will be enveloped in the conventional HF management group, and diuretics will be adjusted based on symptom and physical examination results with or without knowing the LUS‐BL results. Echocardiography examination will be performed for all patients at 12 month post‐discharge. The primary endpoint is consisted of the composite of readmission for worsening HF and all‐cause death during follow up as indicated. The secondary endpoints consisted of the change in the New York Heart Association classification, Duke Activity Status Index, N terminal pro brain natriuretic peptide value, malignant arrhythmia event and 6 min walk distance at each designed follow up, echocardiography‐derived left ventricular ejection fraction, and number of LUS‐BL at 12 month post‐discharge. Safety profile will be recorded and managed accordingly for all patients. Conclusions: This trial will explore the impact of LUS‐BL‐guided intensive HF management on the outcome of discharged HF patients with residual LUS‐BL up to 1 year after discharge in the era of sodium‐glucose cotransporter‐2 inhibitors and angiotensin receptor blocker‐neprilysin inhibitor. Trial Registration: ClinicalTrials.gov: NCT05035459 [ABSTRACT FROM AUTHOR]

Background: To investigate the refractive outcomes of second‐eye adjustment (SEA) methods in different intraocular lens (IOL) power calculation formulas for second eye following bilateral sequential cataract surgery. Methods: This retrospective consecutive case‐series study included 234 eyes from 234 patients who underwent bilateral sequential phacoemulsification and implantation of enVista MX60 in a hospital setting. Postoperative refraction outcomes calculated by standard formulas (SRK/T and Barrett Universal II, BUII) with SEA method were compared with those calculated by an artificial intelligence‐based IOL power calculation formula (PEARL DGS) under second eye enhancement (SEE) method. The median absolute error (MedAE), mean absolute error (MAE) and percentage prediction errors (PE) of eyes within ±0.25 diopters (D), ±0.50 D, ±0.75 D and ± 1.00 D were determined. Results: Overall, the improvement in MedAE after SEA was significant for PEARL DGS (p < 0.01), SRK/T (p < 0.001) and BUII (p = 0.031), which increased from 74.36, 71.37, and 77.78% to 83.33, 80.34, and 79.49% of eyes within a PE of ±0.50 D, respectively. For first eyes with a medium axial length (22–26 mm), PEARL DGS with SEE had the lowest MedAE (0.21 D). For a first‐eye MAE over 0.50 D, SEA method led to significant improvement in the second eye (p < 0.01). Interocular axis length differences exceeding 0.3 mm were associated with weaker effects using SEA in the studied formulas (p > 0.05). Conclusions: Either SEA method with SRK/T and BUII formulas or second‐eye enhancement method based on the PEARL DGS formula can improve postoperative refractive outcomes in second eye. [ABSTRACT FROM AUTHOR]

Though perovskite solar cells (PSCs) or modules (PSMs) are being developed at an unprecedented speed, several obstacles remain to their commercialization. One of the difficult problems is the expensive and unstable Au and Ag counter electrode. Therefore, highly effective, stable, and low‐cost counter electrode materials should be explored. Among various counter electrode materials, carbon is one of the most promising substitutes for their rich sources, low cost, outstanding electrochemical performance, and diversified surface functions. This review summarizes recent achievements of carbon counter electrode materials, which included commercial carbon paste, carbon black, graphite, graphene, carbon nanotubes and their synthetic approaches, modifications, and structure‐function relationships. Moreover, large‐scale carbon counter electrode in PSCs or PSMs are specifically discussed. Hopefully, this recapitulative analysis will draw the attention of relevant researchers to re‐understand the importance of counter electrode and clarify what should be noticed to develop qualified counter electrode materials for PSCs or PSMs. [ABSTRACT FROM AUTHOR]

Doping transition metal ions into polyaniline (PANI) as an attractive electrode material have been regarded as one of the crucial factors to improve the capacitive performance and the cycle stability of supercapacitors due to their excellent metal properties and good conductivity. Herein, PANI has been prepared via in situ facile and low‐cost electro‐polymerization method. At a current density of 0.2 A g−1, the supercapacitor using PANI electrode shows the specific capacitances of 203.0 F g−1 in 1 M H2SO4 electrolyte. To further improve the electrochemical activity of PANI electrode, the transition metal ions M2+ (M2+ = Ni2+, Co2+, Mn2+, and Cu2+) have been doped into PANI electrode via the same electro‐polymerization method. And the supercapacitor with the different doped‐PANI electrode generates the specific capacitances of 364.3, 326.1, 258.5, and 250.6 F g−1 respectively from PANI‐Ni2+, PANI‐Co2+, PANI‐Mn2+, and PANI‐Cu2+, which were superior to 79.5%, 60.6%,27.3%, and 23.4% of the pristine PANI based counterpart under the same test conditions and method. The favorable performances make the different doped‐PANI act as a new resource of the high performance electrode materials of supercapacitor. [ABSTRACT FROM AUTHOR]

Sumoylation is one of the key regulatory mechanisms in eukaryotes. Our previous studies reveal that sumoylation plays indispensable roles during lens differentiation (Yan et al. 2010. Proc Natl Acad Sci USA. 107:21034–21039; Gong et al. 2014. Proc Natl Acad Sci USA. 111:5574–5579). Whether sumoylation is implicated in cataractogenesis, a disease largely derived from aging, remains elusive. In the present study, we have examined the changing patterns of the sumoylation ligases and de‐sumoylation enzymes (SENPs) and their substrates including Pax6 and other proteins in cataractous lenses of different age groups from 50 to 90 years old. It is found that compared with normal lenses, sumoylation ligases 1 and 3, de‐sumoylation enzymes SENP3/7/8, and p46 Pax6 are clearly increased. In contrast, Ubc9 is significantly decreased. Among different cataract patients from 50s to 70s, male patients express more sumoylation enzymes and p46 Pax6. Ubc9 and SENP6 display age‐dependent increase. The p46 Pax6 displays age‐dependent decrease in normal lens, remains relatively stable in senile cataracts but becomes di‐sumoylated in complicated cataracts. In contrast, sumoylation of p32 Pax6 is observed in senile cataracts and increases its stability. Treatment of rat lenses with oxidative stress increases Pax6 expression without sumoylation but promotes apoptosis. Thus, our results show that the changing patterns in Ubc9, SENP6, and Pax6 levels can act as molecular markers for senile cataract and the di‐sumoylated p46 Pax6 for complicated cataract. Together, our results reveal the presence of molecular signature for both senile and complicated cataracts. Moreover, our study indicates that sumoylation is implicated in control of aging and cataractogenesis. [ABSTRACT FROM AUTHOR]

Importance: There is no clear consensus on which intraocular lens (IOL) power calculation formula provides the best refractive prediction in the paediatric population. Background: To evaluate the predictability of desired postoperative refractive outcomes by using six IOL formulas in paediatric cataract cases. Design: Retrospective case series. Participants: A total of 377 eyes in 377 paediatric patients (<13 years of age) who received primary IOL implants in the capsular bag. Methods: This study utilized formulas, namely, SRK II, SRK/T, Hoffer Q, Holladay 1, T2 and Super formula. Prediction errors were calculated based on the difference between the postoperative refraction and the refraction predicted by each formula. Main Outcome Measures: The mean prediction error, mean absolute error, median absolute error, percentages of eyes within the prediction errors of ±0.50 D, ±1.00 D and ± 2.00 D. Results: The mean axial length was 22.48 ± 1.91 mm (<22.0 mm for 161 eyes). The average age at surgery was 55.21 ± 28.01 months (<24 months for 37 eyes). The mean prediction error was positive (hyperopic error) with all formulas. Compared to the other IOL power formulas, SRK II showed significantly higher absolute errors (P <.001). Hoffer Q and Holladay 1 generated the least absolute error, followed closely by Super formula. Multiple logistic analyses indicated that age at time of surgery was an independent factor significantly contributing to the refractive surprise using all formulas. Conclusions and Relevance: SRK II was the least predictable formula in this study. HofferQ and Holladay 1 yielded the best predictive values. [ABSTRACT FROM AUTHOR]

In this study, 2D layer‐structured Ti3C2 is synthesized by using an etching method at lower temperature, which is then applied in dye‐sensitized and perovskite solar cells as counter electrode with higher activity compared with conventional TiC particles counter electrode. The dye‐sensitized solar cells fabricated by using a 2D layer‐structured Ti3C2 counter electrode achieves a power conversion efficiency of 9.57 %, much higher than that of the counterpart device fabricated using a TiC particle counter electrode (7.37 %). The excellent activity of the Ti3C2 electrode can be attributed to the superior charge transfer and mass transport properties, owing to the specific 2D layer structure. Moreover, the fabricated 2D layer‐structured Ti3C2 is applied in perovskite solar cells, thereby achieving a power conversion efficiency of 7.78 % without further optimization. Thus, it is a potential candidate for noble metal electrodes. [ABSTRACT FROM AUTHOR]

To increase the competitiveness of quantum-dotsensitized solar cells (QDSCs) among the various photovoltaic devices, it is necessary to develop new counter-electrode (CE) catalysts to replace the unviable Pt CE. Herein, a series of metalsulfide spheres (e.g., FeS2, Co9S8, NiS, CuS, and ZnS) are designed and synthesized as CE catalysts for QDSCs. As inferred from cyclic voltammetry, electrochemical impedance spectroscopy, and Tafel polarization-curve results, except for ZnS, all of the sulfide spheres perform better than Pt toward Sx 2-/S2- redox-couple regeneration, among which, NiS shows the highest catalytic activity, followed by Co9S8, CuS, and FeS2. The power conversion efficiencies of ZnO nanorod-array photoanode-based QDSCs with sulfide-sphere CEs are 2.5 % (NiS), 2.2 % (Co9S8), 1.8 % (CuS), and 0.8 % (FeS2), much higher than that of their Pt CE-based counterparts (0.30 %). [ABSTRACT FROM AUTHOR]

Novel polyaniline (PANI) nanofiber counter electrodes (CEs) modified with different transition metal ions were synthesized and showed remarkable catalytic activity for dye-sensitized solar cells (DSSCs). The PANI nanofiber-transition metal ion electrodes were characterized by using Fourier transform infrared spectroscopy, scanning electron microscopy, current density-voltage curves, energy-dispersive X-ray spectroscopy, cyclic voltammetry, electrochemical impedance spectroscopy, and Tafel polarization plots. The PANI CEs modified with Ni2+ and Co2+ exhibited low charge-transfer and series resistances, which indicate high electrocatalytic activity toward the iodide redox shuttle. In contrast, the PANI CE modified with Mn2+ did not show much difference in its catalytic behavior, whereas the PANI-Cu2+ CE showed reduced electrochemical performance. The photovoltaic performances of the DSSCs based on the PANI-Ni2+ and PANI-Co2+ CEs were evaluated and they were found to exhibit power conversion efficiency of 4.70 and 4.57 %, higher than that of the pristine PANI-CE-based device (3.87 %). These easily fabricated PANI-metal composites with improved electrochemical activities are promising CEs for DSSCs to replace expensive Pt. [ABSTRACT FROM AUTHOR]

Ta ‐ based compounds show Pt ‐ like behavior: Binary tantalum compounds as counter electrodes (CEs) in dye ‐ sENsitized solar cells (DSCs) demonstrate Pt ‐ like electrocatalytic activity and competitive photovoltaic performance, matching the performance of DSCs with Pt CEs. The first ‐ principle dENsity functional theory (DFT) calculations provide a strategy for understanding the relationship betweEN the electronic structure and the catalytic activity of CE catalysts in DSCs. [ABSTRACT FROM AUTHOR]

The article focuses on the dye-sensitized solar cells (DSCs) which features a moderate power conversion efficiency (PCE), low cost and plasticity. It mentions that the introduction of nanocrystalline semiconductor (metal oxide) mesoporous films is the major break through in the development of DSCs. It further mentions that titanium oxide-based DSCs performance level is low due to the fast recombination dynamics, low voltage value and poor adsorption capacity of sensitizer.

Titanium carbide (TiC) has been used as a counter electrode (CE) catalyst in place of Pt for triiodide reduction in dye-sensitized solar cells (DSCs). Its catalytic activity can be comparable to that of Pt. The effect of the thickness of the TiC layer on the performance of the DSCs was investigated by electrochemical impedance spectroscopy (EIS), cyclic voltammetry (CV), and Tafel polarization measurements. We found that as the film thickness increased, the fill factor and short-circuit current density increased, which led to improved power-conversion efficiency. When the TiC film was thicker than 20 μm, however, no significant continuous improvement in the catalytic activity was observed. A high power-conversion efficiency of 6.46 % was obtained for the DSC by using a TiC CE at the optimized film thickness, a value similar to that obtained with a Pt CE. [ABSTRACT FROM AUTHOR]

Low-cost quantum-dot sensitized solar cells (QDSSCs) were fabricated by using the earth-abundant element SnS quantum dot, novel TiC counter electrodes, and the organic disulfide/thiolate (T2/T−) redox couple, and reached an efficiency of 1.03 %. QDSSCs based on I−/I3−, T2/T−, and S2−/S x2− redox couples were assembled to study the role of the redox couples in the regeneration of sensitizers. Charge-extraction results reveal the reasons for the difference in JSC in three QDSSCs based on I−/I3−, T2/T−, and S2−/S x2− redox couples. The catalytic selectivity of TiC and Pt towards T2/T− and I−/I3− redox couples was investigated using Tafel polarization and electrochemical impedance analysis. These results indicated that Pt and TiC show a similar catalytic selectivity for I−/I3−. However, TiC possesses better catalytic activity for T2/T− than for I−/I3−. These results indicate the great potential of transition metal carbide materials and organic redox couples used in QDSSCs. [ABSTRACT FROM AUTHOR]

Developing highly effective and stable counter electrode (CE) materials to replace rare and expensive noble metals for dye‐sensitized and perovskite solar cells (DSC and PSC) is a research hotspot. Carbon materials are identified as the most qualified noble metal‐free CEs for the commercialization of the two photovoltaic devices due to their merits of low cost, excellent activity, and superior stability. Herein, carbonaceous CE materials are reviewed extensively with respect to the two devices. For DSC, a classified discussion according to the morphology is presented because electrode properties are closely related to the specific porosity or nanostructure of carbon materials. The pivotal factors influencing the catalytic behavior of carbon CEs are also discussed. For PSC, an overview of the new carbon CE materials is addressed comprehensively. Moreover, the modification techniques to improve the interfacial contact between the perovskite and carbon layers, aiming to enhance the photovoltaic performance, are also demonstrated. Finally, the development directions, main challenges, and coping approaches with respect to the carbon CE in DSC and PSC are stated. [ABSTRACT FROM AUTHOR]

A composite electrode of poly(3,4‐ethylenedioxythiophene) (PEDOT)@4A‐molecular sieve is synthesized by a simple electrochemical polymerization method for supercapacitor applications. The prepared PEDOT@4A‐molecular sieve composite exhibits excellent capacitive behavior, with high reversibility in the electrochemical window from −0.8 V and 0.2 V. The specific capacitance of the PEDOT@4A‐molecular sieve composite electrode reaches 163.4 F g−1 at 0.25 A g−1, that is much higher than those of the pristine 4A‐molecular sieve (14.8 F g−1) and PEDOT (117.0 F g−1) electrodes at the same conditions. The composite electrode also presents excellent cycle stability, and the specific capacitance retains 82.8% of its initial value after continuous 1000 charge‐discharge cycles. This work indicates that synthesis of a composite electrode is a promising approach for enhancing the electrochemical properties of the supercapacitor electrode due to the synergistic effect. [ABSTRACT FROM AUTHOR]

Oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) are the cornerstones of rechargeable zinc–air batteries (ZABs). The exploration and rational design of high‐performance, durable, and nonprecious metal bifunctional oxygen electrocatalysts is highly desired for the large‐scale application of rechargeable ZABs. Herein, an effective and straightforward coupling approach is developed to fabricate high‐performance bifunctional ORR/OER electrocatalysts based on novel nanostructured amorphous bimetal Fe/Co hydroxide/oxide nanoparticles (10–20 nm) inlaid on multiwalled N‐dopted carbon nanotubes (FeCo‐DHO/NCNTs). Fe/Co nanoparticles achieve a maximum contact area on the NCNTs, effectively facilitating the rapid electron transport and preventing the aggregation of nanoparticles. Consequently, the as‐prepared FeCo‐DHO/NCNTs show a half‐wave potential of 0.86 V for ORR and a low operating potential of 1.55 V at 10 mA cm−2 for OER in 1.0 m KOH, superior to most bifunctional oxygen electrocatalysts reported so far. Moreover, the assembled all‐solid‐state zinc–air batteries with FeCo‐DHO/NCNTs catalyst as the air electrode demonstrate remarkable stability over long‐term cycling and excellent charging–discharging performance, with a low voltage gap (1.085 V at 60 mA cm−2) and high energy efficiency (60% at 10 mA cm−2) under ambient conditions. The bimetal synergetic coupling interaction favours the formation of amorphous Fe/Co double hydroxide/oxide nanoparticles on N‐doped carbon nanotubes, which provides more transportation channels than that of the highly crystalline phase, and consequently greatly facilitates the sluggish oxygen electrochemical reaction kinetics. The assembled zinc–air batteries demonstrate excellent charging–discharging performance and ultra‐long cycling lifetimes. [ABSTRACT FROM AUTHOR]