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Progress toward durable and energy-dense lithium-ion batteries has been hindered by instabilities at electrolyte-electrode interfaces, leading to poor cycling stability, and by safety concerns associated with energy-dense lithium metal anodes. Solid polymeric electrolytes (SPEs) can help mitigate these issues; however, the SPE conductivity is limited by sluggish polymer segmental dynamics. We overcome this limitation via zwitterionic SPEs that self-assemble into superionically conductive domains, permitting decoupling of ion motion and polymer segmental rearrangement. Although crystalline domains are conventionally detrimental to ion conduction in SPEs, we demonstrate that semicrystalline polymer electrolytes with labile ion-ion interactions and tailored ion sizes exhibit excellent lithium conductivity (1.6 mS/cm) and selectivity (t + ≈ 0.6-0.8). This new design paradigm for SPEs allows for simultaneous optimization of previously orthogonal properties, including conductivity, Li selectivity, mechanics, and processability.

Effective differentiation of prochiral carbon-hydrogen (C-H) bonds on a single methylene carbon via asymmetric metal insertion remains a challenge. Here, we report the discovery of chiral acetyl-protected aminoethyl quinoline ligands that enable asymmetric palladium insertion into prochiral C-H bonds on a single methylene carbon center. We apply these palladium complexes to catalytic enantioselective functionalization of β-methylene C-H bonds in aliphatic amides. Using bidentate ligands to accelerate C-H activation of otherwise unreactive monodentate substrates is crucial for outcompeting the background reaction driven by substrate-directed cyclopalladation, thereby avoiding erosion of enantioselectivity. The potential of ligand acceleration in C-H activation is also demonstrated by enantioselective β-C-H arylation of simple carboxylic acids without installing directing groups.

Abstract Background Overweight is always accompanied by hypertriglyceridemia (HTG), but the change in non-fasting triglyceride (TG) concentration in overweight subjects without postprandial hypertriglyceridemia was unknown. Methods Concentrations of serum lipids were measured at 2 and 4 h in matched overweight (OW group, n = 54) and control subjects (CON group, n = 55) after a daily meal. Concentrations of remnant cholesterol and non-HDL cholesterol were calculated according to the formulas. The diagnostic criteria for non-fasting HTG were based on 2 different consensus statement. ROC curve was used to determine the pointcut of postprandial HTG. Results OW group had higher fasting concentrations of RC and non-HDL-C than CON group. Non-fasting concentrations of triglyceride and RC significantly increased in 2 groups while were higher in OW group (p <.05). The proportion of non-fasting HTG increased after a daily meal in OW group was significantly higher than the percentage of fasting HTG (p <.05). There was a significant correlation between the postprandial concentrations of TG and RC. Conclusions Overweight subjects were more likely to develop non-fasting hypertriglyceridemia and higher concentrations of RC and non-HDL-C. Additionally, 2.0 mmol/l at 4 h after breakfast could be a pointcut value to detect changes in lipid profile of Chinese overweight people. Highlights • Overweight subjects were more likely to develop HTG after a Chinese daily diet. • The non-fasting diagnostic accuracy of HTG was compared by different standards. • 2.0 mmol/L could be a better cut-point to diagnose non-fasting TG elevation. • The correlation between levels of TG and RC was highest at 4 h after breakfast. • 4 h after a diet could be an ideal time to detect the levels of non-fasting lipids. [ABSTRACT FROM AUTHOR]

Background: Pulmonary vein isolation (PVI) alone for persistent atrial fibrillation (PersAF) remains controversial. The characteristics of cryoballoon ablation (CBA) to treat PersAF and the blanking period recurrence are underreported., Methods: This study retrospectively analyzed patients with PersAF undergoing second-generation CBA for de novo PVI. The post-procedural efficacy and survival analysis were compared between patients with different PersAF durations. The multivariate Cox regression analysis was used to detect the risk factors for recurrence. Early and long-term recurrence were analyzed relative to each other., Results: A total of 329 patients were enrolled, with a median PersAF duration of 4.0 months (interquartile range: 2.0-12.0 months); 257 patients (78.1%) were male. Kaplan-Meier analysis of freedom from atrial fibrillation recurrence at 12, 24, and 30 months showed 71.0%, 58.5%, and 54.9%, respectively. Early PersAF had a relatively favorable survival rate and a narrow P-wave duration of restoring sinus rhythm compared with that of PersAF lasting more than three months ( P < 0.05). The multivariate Cox regression analysis revealed that PersAF duration and left atrial anteroposterior diameter ≥ 42 mm were the risk factors for atrial fibrillation recurrence after CBA [hazard ratio (HR) = 1.89, 95% CI: 1.01-1.4, P = 0.042; HR = 3.6, 95% CI: 2.4-5.4, P < 0.001, respectively]. The blanking period recurrence predicted the long-term recurrence ( P < 0.0001)., Conclusions: CBA of PersAF had safety and efficacy to reach de novo PVI. The PersAF duration and left atrial size were risk factors for atrial fibrillation recurrence after CBA. Blanking period recurrence was associated with long-term recurrence., (© 2022 JGC All rights reserved; www.jgc301.com.)

The first example of free amine γ-C(sp 3 )-H fluorination is realized using 2-hydroxynicotinaldehyde as the transient directing group. A wide range of cyclohexyl and linear aliphatic amines could be fluorinated selectively at the γ-methyl and methylene positions. Electron withdrawing 3,5-disubstituted pyridone ligands were identified to facilitate this reaction. Computational studies suggest that the turnover determining step is likely the oxidative addition step for methylene fluorination, while it is likely the C-H activation step for methyl fluorination. The explicit participation of Ag results in a lower energetic span for methylene fluorination and a higher energetic span for methyl fluorination, which is consistent with the experimental observation that the addition of silver salt is desirable for methylene but not for methyl fluorination. Kinetic studies on methyl fluorination suggest that the substrate and PdL are involved in the rate-determining step, indicating that the C-H activation step may be partially rate-determining. Importantly, an energetically preferred pathway has identified an interesting pyridone-assisted bimetallic transition state for the oxidative addition step in methylene fluorination, thus uncovering a potential new role of the pyridone ligand.

We report a general protocol for γ-C(sp 3 )-H acyloxylation and alkoxylation of free amines using 2-hydroxynicotinaldehyde as the transient directing group. In the presence of an electrophilic fluorinating bystanding oxidant and acetic acid, a wide range of aliphatic amines could be oxygenated selectively at the γ-methyl positions. A vast variety of aryl, heteroaryl, and aliphatic acids could also be successfully coupled under this C-O bond formation reaction to afford amine containing esters. Switching the nucleophile from acids to alcohols enables alkoxylation of free amines. Importantly, natural products and drug molecules such as ibuprofen, isozepac, fenbufen, and lithocholic acid are all compatible coupling partners. Notably, synthesis of these mono-protected amino alcohols from free amino alcohols using conventional selective protection are not always feasible.

Low-altitude unmanned aerial vehicles (UAV) remote sensing system overcomes the deficiencies of space and aerial remote sensing system in resolution, revisit period, cloud cover and cost, which provides a novel method for ecological research on mesoscale. This study introduced the composition of UAV remote sensing system, reviewed its applications in species, population, community and ecosystem ecology research. Challenges and opportunities of UAV ecology were identified to direct future research. The promising research area of UAV ecology includes the establishment of species morphology and spectral characteristic data base, species automatic identification, the revelation of relationship between spectral index and plant physiological processes, three-dimension monitoring of ecosystem, and the integration of remote sensing data from multi resources and multi scales. With the development of UAV platform, data transformation and sensors, UAV remote sensing technology will have wide application in ecology research.

Pd(II)-catalyzed γ-C(sp 3 )-H arylation of primary amines is realized by using 2-hydroxynicotinaldehyde as a catalytic transient directing group. Importantly, the catalyst and the directing group loading can be lowered to 2% and 4% respectively, thus demonstrating high efficiency of this newly designed transient directing group. Heterocyclic aryl iodides are also compatible with this reaction. Furthermore, swift synthesis of 1,2,3,4-tetrahydronaphthyridine derivatives is accomplished using this reaction.

Achieving selective C-H activation at a single and strategic site in the presence of multiple C-H bonds can provide a powerful and generally useful retrosynthetic disconnection. In this context, a directing group serves as a compass to guide the transition metal to C-H bonds by using distance and geometry as powerful recognition parameters to distinguish between proximal and distal C-H bonds. However, the installation and removal of directing groups is a practical drawback. To improve the utility of this approach, one can seek solutions in three directions: 1) Simplifying the directing group, 2) using common functional groups or protecting groups as directing groups, and 3) attaching the directing group to substrates via a transient covalent bond to render the directing group catalytic. This Review describes the rational development of an extremely simple and yet broadly applicable directing group for Pd(II) , Rh(III) , and Ru(II) catalysts, namely the N-methoxy amide (CONHOMe) moiety. Through collective efforts in the community, a wide range of C-H activation transformations using this type of simple directing group have been developed., (© 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)