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Low Li+ transference number in liquid electrolytes can lead to uneven lithium deposition and dendrite growth, reducing coulombic efficiency and cycle life of lithium metal batteries. In this study, metal‐organic frameworks (MOFs) are used as electrolyte modulator to regulate Li+ transport. The ‐NH2 group introduced into MOFs can form hydrogen bonds with anions in the electrolyte, immobilizing these anions and thereby facilitating the migration of cations. As a result, a uniform and dense deposition morphology of lithium was achieved. The Li+ transference number is increased from 0.26 to 0.57. The assembled Li||Li symmetrical cell can stably cycle for over for 900 h with an average overpotential below 20 mV. In addition, the rate performance of the battery can be enhanced. [ABSTRACT FROM AUTHOR]

The electrolyte chemistry is crucially important for promoting the practical application of lithium metal batteries (LMBs). Here, we demonstrate for the first time that 1,3‐dimethylimidazolium dimethyl phosphate (DIDP) and trimethylsilyl trifluoroacetate (TMSF) can undergo in situ transesterification in carbonate electrolyte to generate dimethyl trimethylsilyl phosphate (DTMSP) and 1,3‐dimethylimidazolium trifluoroacetate (DITFA) as multifunctional additives for LMBs. H2O and HF can be removed by the Si−O group in DTMSP to improve the moisture resistance of electrolyte and the stability of cathode. Furthermore, the dissolution of lithium nitrate (LiNO3) in carbonate electrolyte can be promoted by the trifluoroacetate anion (TFA−) in DITFA, thereby optimizing the solvation structure and transport kinetics of Li+. More importantly, both DTMSP and DITFA tend to preferential redox decomposition due to the low lowest unoccupied molecular orbital (LUMO) and high highest occupied molecular orbital (HOMO). Consequently, a thin and robust layer rich in P/N/Si on the cathode and an inorganic‐rich layer (e.g. Li3N/Li3P) on the anode can be constructed and superior electrochemical performances are achieved. This artificial transesterification strategy to introduce favorable additives paves an efficient and ingenious route to high‐performance electrolyte for LMBs. [ABSTRACT FROM AUTHOR]

Owing to their distinctive 1,3‐dipolar structure, the catalytic asymmetric hydrogenation of nitrones to hydroxylamines has been a formidable and longstanding challenge, characterized by intricate enantiocontrol and susceptibility to N−O bond cleavage. In this study, the asymmetric hydrogenation and transfer hydrogenation of nitrones were accomplished with a tethered TsDPEN‐derived cyclopentadienyl rhodium(III) catalyst (TsDPEN: p‐toluenesulfonyl‐1,2‐diphenylethylene‐1,2‐diamine), the reaction proceeds via a novel 7‐membered cyclic transition state, producing chiral hydroxylamines with up to 99 % yield and >99 % ee. The practical viability of this methodology was underscored by gram‐scale catalytic reactions and subsequent transformations. Furthermore, mechanistic investigations and DFT calculations were also conducted to elucidate the origin of enantioselectivity. [ABSTRACT FROM AUTHOR]

The carbonate electrolyte chemistry is a primary determinant for the development of high‐voltage lithium metal batteries (LMBs). Unfortunately, their implementation is greatly plagued by sluggish electrode interfacial dynamics and insufficient electrolyte thermodynamic stability. Herein, lithium trifluoroacetate‐lithium nitrate (LiTFA−LiNO3) dual‐salt additive‐reinforced carbonate electrolyte (LTFAN) is proposed for stabilizing high‐voltage LMBs. We reveal that 1) the in situ generated inorganic‐rich electrode‐electrolyte interphase (EEI) enables rapid interfacial dynamics, 2) TFA− preferentially interacts with moisture over PF6− to strengthen the moisture tolerance of designed electrolyte, and 3) NO3− is found to be noticeably enriched at the cathode interface on charging, thus constructing Li+‐enriched, solvent‐coordinated, thermodynamically favorable electric double layer (EDL). The superior moisture tolerance of LTFAN and the thermodynamically stable EDL constructed at cathode interface play a decisive role in upgrading the compatibility of carbonate electrolyte with high‐voltage cathode. The LMBs with LTFAN realize 4.3 V‐NCM523/4.4 V‐NCM622 superior cycling reversibility and excellent rate capability, which is the leading level of documented records for carbonate electrode. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Transition metal‐catalyzed asymmetric transfer hydrogenation has been proven to be a powerful approach for the synthesis of chiral alcohols. Herein, a highly efficient and enantioselective transfer hydrogenation of dibenzoheptaheterocyclic ketones catalyzed by an arene‐tethered TsDPEN‐based Rh(III) catalyst has been successfully developed, and a variety of dibenzoheptaheterocyclic ketones were reduced by a 1/1 mixture of formic acid and DBU (1,8‐diazabicyclo[5.4.0]undec‐7‐ene) with high yields and enantioselectivities. With this method, the asymmetric reduction of 7,8‐difluorodibenzo[b,e]thiepin‐11(6H)‐one has been realized, providing the key intermediate of baloxavir marboxil with >99% yield and >99% ee at a substrate/catalyst molar ratio of 1000. [ABSTRACT FROM AUTHOR]

Silicon‐based materials have been regarded as the most flourishing anode materials owing to the incomparable specific capacity. However, their commercial application is obstructed by huge volume expansion and particle pulverization, which subsequently lead to the stress concentration and the loss of electrical contact, eventually resulting in poor cycling stability and lousy rate performance. Herein, an ion‐conductive binder with boosted ion‐conductivity is proposed by free radical polymerization between acrylic acid and lithiated 2‐acrylamido‐2‐methyl‐1‐propanesulfonic acid (LiAMPS). With the aid of ample sulfonic acid anionic groups, rapid lithium‐ion diffusion can be achieved to improve the transport kinetics and rate performance. Meanwhile, superior mechanical properties of binder can alleviate the stress concentration to avoid particle pulverization by noncovalent hydrogen bond. The synergistic strategy of constructing lithium‐ion diffusion pathway and alleviating the stress concentration can make a preeminent improvement on Li+ diffusion coefficient and maintain a high structural integrity of electrode. Benefiting from the synergistic effect, the SiOx microparticle anode delivers a high capacity of 587.8 mAh g−1 after 400 cycles at 1C and preeminent rate performance of 648.6 mAh g−1 at 5C. Such a synergistic design strategy endows P(AA‐co‐LiAMPS) binder with a promising potential for high energy density silicon‐based anodes. [ABSTRACT FROM AUTHOR]

The catalytic performance and the stability of the water electrolysis system have perplexed the practical splitting water. Herein, 3D‐printed metallic electrodes with Janus porosity are reported, which can achieve the efficient bubble emission and provide high surface area. After a further one‐step treatment, the catalysts of Ru–Ni(OH)2 and Fe–Ni(OH)2 nanoarrays are in situ grown on the electrodes. Theoretical calculations and systematical experiments confirm the synergistic effect of the gradient morphology and the in situ grown catalysts. The electrolyzer shows unprecedented activity with an overpotential of 98 mV for hydrogen evolution reaction and 343 mV for oxygen evolution reaction at the current density of 500 mA cm−2 and outperformed stability, which can deliver 500 mA cm−2 at the voltage of 1.638 V for 2100 h with no significant decay, far exceedingly most state‐of‐the‐art electrolyzers. This 3D electrode with controllable bubble motions offers a viable solution for future industrial sustainable hydrogen production technology. [ABSTRACT FROM AUTHOR]

Aqueous rechargeable zinc‐ion batteries (ARZBs) are impeded by the mutual problems of unstable cathode, electrolyte parasitic reactions, and dendritic growth of zinc (Zn) anode. Herein, a triple‐functional strategy by introducing the tetramethylene sulfone (TMS) to form a hydrated eutectic electrolyte is reported to ameliorate these issues. The activity of H2O is inhibited by reconstructing hydrogen bonds due to the strong interaction between TMS and H2O. Meanwhile, the preferentially adsorbed TMS on the Zn surface increases the thickness of double electric layer (EDL) structure, which provides a shielding buffer layer to suppress dendrite growth. Interestingly, TMS modulates the primary solvation shell of Zn2+ ultimately to achieve a novel solvent co‐intercalation ((Zn‐TMS)2+) mechanism, and the intercalated TMS works as a "pillar" that provides more zincophilic sites and stabilizes the structure of cathode (NH4V4O10, (NVO)). Consequently, the Zn||NVO battery exhibits a remarkably high specific capacity of 515.6 mAh g−1 at a low current density of 0.2 A g−1 for over 40 days. This multi‐functional electrolytes and solvent co‐intercalation mechanism will significantly propel the practical development of aqueous batteries. [ABSTRACT FROM AUTHOR]

Summary: Resonant converters have been widely applied in many fields, such as electric vehicles, renewable energy sources, and switch‐mode power supply. Conventional resonant converters generally adopt pulse frequency modulation (PFM), which would cause an extremely wide frequency variation range under wide output applications. However, it would lead to high electromagnetic interference (EMI), low utilization of magnetic components, and loss of soft switching features. For catering to wide output range applications, this paper proposes a self‐adaptive narrow frequency range PFM and asymmetrical voltage‐cancelation hybrid modulation strategy to solve the above problem. The advantages of the proposed strategy include (1) narrow frequency variation range; (2) self‐adaptive shift frequency; and (3) full process achievement of zero voltage switch. The modulation strategy and operational principle and performance analysis of the proposed method are given. Eventually, a series resonant converters–based experimental platform was implemented to verify the proposed strategy. [ABSTRACT FROM AUTHOR]

To fulfill the emerging demand for drug therapy, the Y/Tb/Gd ternary layered rare‐earth hydroxide nanocone is developed as a new multifunctional delivery system for one of the most popular drugs, aspirin. Dodecyl sulfate intercalation is firstly used for the drug carrier which can form hollow nanocones and owns low binding energy, leading to the facile synthesis of organic–inorganic hybrid drug delivery system. The aspirin can be loaded rapidly (as short as 5 min) and released continuously (as long as 48 h) by YTG system through anion exchange, which will be favorable for sustained therapy. Meanwhile, the intercalated aspirin can enhance the green light luminescence of Tb3+ with peak position at 543 nm through energy transfer, which can be utilized as fluorescence probe to monitor the drug loading and release process. The magnetization of Gd3+ can also be improved by structural evolution induced by aspirin intercalation, which can be applied as magnetic resonance imaging contrast agent simultaneously. The current research provides a novel pathway for the invention of multifunctional drug delivery system, which hopefully is to be put into service in biomedical fields in the near future. [ABSTRACT FROM AUTHOR]

With ever‐increasing pursuit for high‐value output in recycling spent lithium‐ion batteries (LIBs), traditional recycling methods of cathodes tend to be obsolete because of the complicated procedures. Herein, we first upcycle spent polycrystal LiNi0.88Co0.095Al0.025O2 (S‐NCA) to high value‐added single‐crystalline and Li‐rich cathode materials through a simple but feasible LiOH‐Na2SO4 eutectic molten salt strategy. The in situ X‐ray diffraction technique and a series of paratactic experiments record the evolution process of upcycling and prove that excessive Li occupies the transition metal (TM) layers. Beneficial from the single‐crystalline and Li‐rich nature, the regenerated NCA (R‐NCA) exhibits remarkably enhanced electrochemical performances in terms of long‐term cyclability, high‐rate performance and low polarization. This approach can also be successfully extended to other cathode materials e.g. LiNixCoyMnzO2 (NCM) and mixed spent NCAs with varied degree of Li loss. [ABSTRACT FROM AUTHOR]

With the gradual depletion of traditional zinc resources, the full use of various non‐traditional zinc‐containing resources has received intensive attention. However, the efficient recovery of zinc ions with low concentrations remains challenging. Here efficient and continuous recovery of zinc ions in ammoniacal chloride media by a flat supported liquid membrane system is achieved, using Cyanex923 and TBP mixed extractant as the membrane phase. This article discusses the synergistic effect between Aliquat336, Cyanex923 and TBP, the effects of feed pH, total ammonia concentration, Cl− concentration and temperature on Zn(II) transport. [ABSTRACT FROM AUTHOR]

LiNO3 is an effective additive for improving the performance of Li metal anodes. However, the practical application of LiNO3 is limited due to its poor solubility. Here, a novel electrolyte additive of MgAl layered double hydroxides (LDHs) with open interlayered anionic vacancies is proposed. The electropositive MgAl LDHs promote the spontaneous coordination of NO3− into anionic vacancies of LDH interlayers via memory effect, rehydrating to original NO3−‐MgAl LDHs structure and accelerating LiNO3 dissolution. The reconstructed NO3−‐MgAl LDHs play a crucial role as sustainable nitrate resources, preventing partial NO3− from participating in the Li+ solvent sheath to reduce the solvation binding energy. Moreover, MgAl LDHs absorb the anions due to electrostatic attraction, accounting for more dissociated Li+ and active Li+ migration in carbonate electrolytes. NO3− stored in MgAl LDHs is also preferentially reduced to form Li3N‐rich solid electrolyte interphase (SEI), decreasing the activation energy barrier for Li+ transport and striving to form a uniform Li deposition. The cells assembled with MgAl LDHs and LiNO3 additives deliver high Coulombic efficiency, excellent rate capability, and high capacity retention. This strategy provides new insights into LiNO3‐promotor design and excavates the potential of LDHs materials for Li metal batteries. [ABSTRACT FROM AUTHOR]

The rampant dendrites and hydrogen evolution reaction (HER) resulting from the turbulent interfacial evolution at the anode/electrolyte are the main culprits of short lifespan and low Coulombic efficiency of Zn metal batteries. In this work, a versatile protective coating with excellent zincophilic and amphoteric features is constructed on the surface of Zn metal (ZP@Zn) as dendrite‐free anodes. This kind of protective coating possesses the advantages of reversible proton storage and rapid desolvation kinetics, thereby mitigating the HER and facilitating homogeneous nucleation concomitantly. Furthermore, the space charge polarization effect promotes charge redistribution to achieve uniform Zn deposition. Accordingly, the ZP@Zn symmetric cell manifests excellent reversibility at an ultrahigh cumulative plating capacity of 4700 mAh cm−2 and stable cycling at 80 % depth of discharge (DOD). The ZP@Zn//V6O13 pouch cell also reveals superior cycling stability with a high capacity of 326.6 mAh g−1. [ABSTRACT FROM AUTHOR]

Solid‐state electrolytes hold great promise for lithium‐based batteries with high energy density and safety. Here, novel metal‐organic frameworks (MOFs) based composite membranes were fabricated by a rolling process and subsequently employed as quasi solid‐state electrolytes, exhibiting improved ionic conductivity and Li+ transference number as well as stable electrochemical window. Furthermore, the MOF‐based membranes presented a significant effect in modulating the stripping/plating process of Li and resulted in a dendrite‐free Li deposition. The corresponding LiFePO4|Li batteries were assembled and presented improved rate capability and high Coulombic efficiency, offering a new option for MOF‐based electrolytes. [ABSTRACT FROM AUTHOR]

The lattice‐oxygen‐mediated mechanism is considered as a reasonable mechanism for the electrochemical catalytic oxygen evolution reaction (OER) of NiFe layered double hydroxides (LDHs). A NiFe LDH with distinct lattice contraction and microcrystallization was synthesized via a simple one‐step method using sodium gluconate. The lattice contraction is attributed to the interaction of carbon in sodium gluconate and iron in NiFe LDH. The NiFe LDH with optimized microcrystallization and lattice contraction shows a low overpotential of 217 mV at a current density of 10 mA cm−2 and excellent durability of 20 h at a high current density of 100 mA cm−2. The results revealed that a contractive metal–oxygen bond could boost the intrinsic activity of active sites and the microcrystallization promotes an increase in the number of active sites in terms of unit area. The chemical environment of oxygen elemental characterization and resistance at different chronopotentiometry times confirm that the lattice oxygen element is indeed involved in the process of OER, supporting the lattice‐oxygen‐mediated mechanism of NiFe LDH. Density functional theory calculations reveal that contractive metal–oxygen bonds induced a reduction of the adsorption energy barrier of intermediate products, thus improving the intrinsic catalytic activity. The special characteristics of microcrystallization and lattice contraction of NiFe LDH provide a strategy to improve both the number and the intrinsic activity of active sites in a versatile manner. [ABSTRACT FROM AUTHOR]

Carbonate‐based electrolytes are incompatible with lithium (Li) metal anode because the generated solid electrolyte interphase (SEI) undergoes repeated breakage‐repair, resulting in the accumulation of inactive Li including Li+ compounds and electrically isolated dead Li0 in the SEI. Therefore, exploiting a suitable strategy to construct a stable SEI while efficiently rejuvenating the inactive Li capacity is urgent and more thoughtful than just building a stereotyped SEI layer. Herein, an innovative strategy is proposed of high‐concentration additive (HCA) of LiNO3 inspired by (localized) high‐concentration electrolyte and inactive Li restoration methodology via triiodide/iodide (I3−/I−) redox couple to improve the compatibility of carbonate‐based electrolytes. The HCA of LiNO3 can maintain the cation–anion aggregates solvation structures in the carbonate‐based bulk electrolyte and induce the in situ formation of superior‐ionic‐conductivity NO3−‐derived SEI. Moreover, the reversible I3−/I− redox couple can further optimize the SEI and constantly rejuvenate the inactive Li including solvent/LiNO3‐derived Li2O, a derivative has almost been acquiescent in LiNO3‐additive electrolytes, and dead Li0 into delithiated cathode. Consequently, epitaxy‐like planar Li deposition, better reversibility, and higher capacity retention can be realized and are systematically verified by Li||Cu half cells, full cells with excess/limited Li (N/P ratio = 1.5) and anode‐free lithium metal batteries. [ABSTRACT FROM AUTHOR]

It is widely recognized that SiOx is a feasible anode material for the next generation lithium‐ion batteries because of its high capacity, low cost, environmental friendliness, and abundant available storage. However, the enormous volume expansion and irreversible by‐products during lithiation can result in the rapid capacity degradation and low coulombic efficiency. The commercial binders of carboxymethyl cellulose (CMC) and polyvinylidene difluoride cannot afford the volume change. Herein, a rational crosslinked binder is synthesized through an in situ condensation reaction between CMC and phthalic acid (PA). With rich hydroxyl groups bonded to the homogeneous SiO2 nanodomain, the enormous volume expansion of the SiOx anode can be restricted efficaciously. Therefore, the SiOx@CMC‐PA electrode delivers a reversible specific capacity of 671 mAh g−1 at 500 mA g−1 after 200 cycles and a high average coulombic efficiency of 99.2%, much higher than 226.3 mAh g−1 of SiOx@CMC electrode. It demonstrates that this work offers a cost effective and available strategy to achieve high performance binder for Si‐based anode materials. [ABSTRACT FROM AUTHOR]

In the application of bipolar DC bus configuration in the DC nanogrid, the unbalanced voltage of two outputs in bipolar DC bus, due to the unbalanced conditions of loads and/or energy sources, will cause deterioration of the power quality of the bus and may damage the switch, affecting the stability and safety of the system. In order to solve the problem of unbalanced voltage of two outputs, interleaved series capacitor based dual‐output converter with a high conversion ratio is presented in this paper. By applying negative current mode (NCM) to the main inductor, the character of two‐output self‐balancing and zero voltage switching (ZVS) of all switches for such this topology configuration is achieved. In the NCM mode, the parallel diodes of main switches are not conducted during dead time and guarantee the flowing path to load side. Thus, based on this condition, volt‐second balance of main inductor is obtained to get the character of two‐output self‐balancing. Furthermore, by adopting series capacitor in the proposed topology and based on the charge‐balance of the intermediate block capacitor, inductor current existed in the two phase could be auto‐sharing. Comprehensive operational principle analysis, loss analysis, and efficiency of the proposed converter under different load conditions have been given, and the comparison analysis of three operation modes and selection of negative current mode is clarified. Small signal model of the proposed converter is described to convenient for the controller design. Finally, simulation results and a 20–220 V prototype are built to verify the character analysis of the proposed converter. [ABSTRACT FROM AUTHOR]

Due to the linear coordination nature of gold(I) catalysts, achieving high enantiocontrol in asymmetric gold catalysis is a great challenge. To improve the enantiocontrol of gold catalysis, an ion‐pairing strategy was therefore proposed. A series of bifunctional P,N ligands based on chiral spirocyclic and biaryl scaffolds were synthesized and applied in the gold(I)‐catalyzed desymmetric lactonization of alkynylmalonic acids. A wide range of chiral lactones containing an α‐position quaternary stereocenter were synthesized with high yields, excellent regioselectivity and enantioselectivity under mild reaction conditions. The synthetic utilities of the current reaction were demonstrated by gram‐scale synthesis and transformations of chiral lactones. The origin of enantioselectivity and the role of the alcohol additive were elucidated via control experiments and DFT calculations. [ABSTRACT FROM AUTHOR]

Objectives: Myocardial infarction (MI) commonly occurs in patients with coronary artery disease and have high mortality. Current clinical strategies for MI still limited to reducing the death of myocardial cells but failed to replace these cells. This study aimed to investigate the role of fibroblast growth factor 6 (FGF6) in enhancing the proliferative potential of cardiomyocytes (CMs) after ischemic injury via the Hippo pathway. Materials and Methods: Expression of FGF6 protein was analysed in mice with MI induced by ligation of the left anterior descending coronary artery. Activation of the Hippo pathway and the proliferation potential were examined in ischemic CMs, treated with FGF6 protein or transfected with an adeno‐virus carrying FGF6 sh‐RNA. Immunofluorescence staining and western blotting were performed to assess the relationship between FGF6 and the Hippo pathway. Results: We found that FGF6 expression was significantly increased in the MI mouse model. Knockdown of FGF6 synthesis resulted in poorer heart function after MI. By contrast, treatment with recombinant human FGF6 protein improved heart function, reduced infarct size, and promoted cardiac repair. Additionally, FGF6 restrains the activation of the Hippo pathway and subsequently promotes nuclear accumulation of YAP. This was largely counteracted by treatment with extracellular signal‐regulated kinase 1/2 (ERK1/2) inhibitor U0126. Conclusion: FGF6 inhibits the Hippo pathway via ERK1/2, and facilitates nuclear translocation of YAP, and thereby promotes cardiac repair after MI. [ABSTRACT FROM AUTHOR]

Strategy of anchoring alloy nanoparticles made up of the efficient catalytic element (e.g., Ni, Fe) on dodecyl sulfate (DS‐)‐intercalated NiFe layered double hydroxides (DS‐‐NiFe LDH) obtained by a convenient one‐step hydrothermal coprecipitation method for essentially enhancing oxygen evolution reaction (OER) performance was proposed. The results of structural characterization indicate Pt2FeNi alloy nanoparticles evenly distribute on the surface of DS‐‐NiFe LDH. The sizes of the Pt2FeNi nanoparticles, closely related to their OER performance, could be well‐controlled by adjusting the amount of H2PtCl6 addition. The composite structure of as‐prepared product was stable during processes of synthesis, exfoliation, self‐assembly, and subsequent electrocatalytic OER. Rigorous electrochemical test proving the contributing catalytic active sites was located at the interface between Pt2FeNi and DS‐‐NiFe LDH, and the Ni and Fe were the major active elements while O atoms are adsorption sites. The formation of Pt2FeNi nanoparticles could greatly prompt the reduction of Tafel slope. The best‐performing Pt2FeNi/DS‐‐NiFe LDH with a Pt content of 0.98 wt% achieved low overpotential of 204 mV at 10 mA cm−2 and 262 mV at 50 mA cm−2. This work provides a convenient and effective strategy to create additional active sites for enhancing OER performance of NiFe LDH and make contribution to its wide application. [ABSTRACT FROM AUTHOR]

Converting CO2 into carbon‐based fuels is promising for relieving the greenhouse gas effect and the energy crisis. However, the selectivity and efficiency of current electrocatalysts for CO2 reductions are still not satisfactory. In this paper, the development of machine learning methods in screening CO2 reduction electrocatalysts over the recent years is reviewed. Through high‐throughput calculation of some key descriptors such as adsorption energies, d‐band center, and coordination number by well‐constructed machine learning models, the catalytic activity, optimal composition, active sites, and CO2 reduction reaction pathway over various possible materials can be predicted and understood. Machine learning is now realized as a fast and low‐cost method to effectively explore high performance electrocatalysts for CO2 reduction. [ABSTRACT FROM AUTHOR]

The regulation of lithium plating/stripping behavior is considered to be critical for next-generation safe and high-energy-density lithium metal batteries. Lithium deposition with maximum granular size and minimum microstructural tortuosity can significantly improve the lithium plating/stripping efficiency. Here, a self-assembled organosilane layer with nanopores is constructed on Cu current collector surface via a thiol-Cu reaction. In contrast to typical stacked-particle morphology with small grain size and high specific area in ether electrolyte, dough-like and lateral-growth lithium deposition can be plated on the modified Cu current collector due to the low surface energy of a lithiophilic Si-O-Si membrane. The planar and dense lithium deposition contributes to the stable implementation of up to near 500 cycles in full cells with high-loading LiFePO4 cathode. Anticorrosion in rigorous Cl-ion containing solution can even be achieved due to the corrosive repellency of hydrophobic organosilane. A high Coulombic efficiency (97.12%) is remained after corroding for 300 min. Moreover, the irreversible capacity loss caused by galvanic corrosion, an ignored but crucial aspect, has been significantly suppressed due to the passivation of high-redox-potential Cu by organosilane coating. [ABSTRACT FROM AUTHOR]

Chiral carboxylic acids are important compounds because of their prevalence in pharmaceuticals, natural products and agrochemicals. Asymmetric hydrogenation of α,β‐unsaturated carboxylic acids has been widely recognized as one of the most efficient synthetic approaches to afford such compounds. Although related asymmetric hydrogenation of di‐ and trisubstituted unsaturated acids with noble metals is well established, asymmetric hydrogenation of challenging tetrasubstituted α,β‐unsaturated carboxylic acids is rarely reported. We demonstrate enantioselective hydrogenation of cyclic and acyclic tetrasubstituted α,β‐unsaturated carboxylic acids via cobalt(II) catalysis. This protocol showed broad substrate scope and gave chiral carboxylic acids in good yields with excellent enantiocontrol (up to 98 % yield and 99 % ee). Combined experimental and computational mechanistic studies support a CoII catalytic cycle involving migratory insertion and σ‐bond metathesis processes. DFT calculations reveal that enantioselectivity may originate from the steric effect between the phenyl groups of the ligand and the substrate. [ABSTRACT FROM AUTHOR]

Purpose: Over the last two decades, extended criteria have promoted an increased number of donor livers available for liver transplantation. But posttransplant graft loss is still a major concern. Macrovesicular hepatic steatosis (MHS) is recognized as the most significant prognostic histologic parameter in predicting posttransplant graft loss. We aimed to evaluate the utility of ex vivo volumetric quantitative MRI for quantifying MHS before liver transplantation using proton density fat‐fraction (PDFF‐MRI) histogram analysis. Methods: PDFF‐MRI was performed at 3.0T in 40 livers. We obtained histogram parameters of whole‐liver volume of interest, including the mean, median, 5th, 10th, 25th, 75th, 90th, and 95th percentile PDFF; skewness; kurtosis; entropy; and volume. Results: Livers from 40 cadaveric donors were included, and histologic ex vivo fat quantification was available for 33 livers. Ten livers had MHS and 23 had normal fat content. The MHS group had higher mean, median, 5th, 10th, 25th, 75th, 90th, and 95th percentile PDFF, and entropy than the group with normal fat content (P <.05). Median PDFF had greater area under the curve value than other parameters. Mean PDFF showed an excellent correlation with entropy and a moderate correlation with MHS quantification on histology. Conclusions: Ex vivo volumetric quantitative PDFF‐MRI histogram analysis is a very useful and noninvasive method to detect MHS before liver transplantation. Median PDFF was the best predictor of the presence of MHS. Entropy is a very promising parameter. [ABSTRACT FROM AUTHOR]

Silicon (Si) is regarded as a promising anode material for next‐generation lithium‐ion batteries due to its ultrahigh theoretical capacity. However, the drastic volume change and the continuous solid electrolyte interphase (SEI) formation during the lithiation/delithiation process seriously hinder its practical application as commercial anodes. Herein, macrocyclic beta‐cyclodextrin (β‐CD) has been designed as the diffusion channel for lithium ions at the molecular scale. The diameter of molecular channel is approximately comparable with the solvated lithium ions, which enables the transport of lithium ions and prevents the penetration of solvent molecules. Moreover, the addition of β‐CD changes the formation behavior of SEI layer and stabilizes the Si nanoparticles. The enhanced electrochemical performances in terms of fast kinetics and improved stability have been achieved. The Si anode with the particularly selected lithium‐ion diffusion channel and stabilized SEI layer exhibits a high reversible capability of 2 562 mAh g−1 after 50 cycles at the current density of 500 mA g−1, 1 944 mAh g−1 after 200 cycles at the current density of 1 A g−1, and high rate performance. The novel strategy of molecular channel for lithium‐ion diffusion offers new insights into the design of alloy‐typed anode electrodes with high capacity for lithium‐ion batteries. [ABSTRACT FROM AUTHOR]

The performance of lithium batteries is heavily governed by the transport of ions within the electrolytes. Commercial liquid electrolytes, however, generally exhibit a low lithium‐ion transference number, causing concentration polarization, side reactions, and deteriorated battery performance. Herein, a novel class of electrolyte additives based on particles of metal–organic framework is proposed to immobilize the anions while allowing efficient transport of lithium ions in the electrolytes. The use of such additives effectively increases the lithium‐ion transference number, enhances the rate capability, and prolongs the cycling life, which provides a facile yet effective strategy toward lithium batteries with dramatically improved performances. [ABSTRACT FROM AUTHOR]

Layered metal hydroxides (LMHs) are regarded as a novel and important class of inorganic functional materials. They have unique layered structure and variable chemical compositions that can be readily tuned. In this review, summarized are the recent advances of synthetic routes to the LMHs with designed morphology, composition, and function for electrocatalysis. Versatile products can be readily derived by hybridization, anion‐exchange, surface modification, self‐assembly, etc. More importantly, LMHs can be artificially exfoliated into unilamellar nanosheets with a molecular‐level thickness of about 1 nm versus 2D lateral size in submicrometer or micrometer scale. Molecular‐scale assembly can be then applied to fabricate superlattice‐like composites and functional nanofilms with high quality. The hydroxides can be transformed into oxides, nitrides, or other compounds via different preparation procedures, which can further extend their application prospects. In this regard, the most promising electrocatalysis‐related applications of LMHs and their derivatives are reviewed, such as oxygen evolution reaction, oxygen reduction reaction, hydrogen evolution reaction, CO2 reduction reaction, alcohol or urea electrooxidation, etc. At last, future challenges are also discussed from the aspect of synthesis and application, as well as encouraging advancements are anticipated. [ABSTRACT FROM AUTHOR]

Morphology and composition tuning of layered materials is evaluated to influence their electrochemical performance for energy storage and conversion applications. Layered Co1−xNix hydroxides (x=0, 1/2, 1/3, 1/4, 1) of three different morphologies—nanocones, 2 D nanosheets obtained by the rapid exfoliation of nanoconical counterparts, and 2 D superlattice‐like nanostructures alternately restacked by the oppositely charged hydroxide and graphene oxide (GO) nanosheets—have been systematically investigated for electrocatalytic oxygen oxidation. High activity is obtained with the 2 D Co2/3Ni1/3 hydroxide nanosheets/GO superlattice (Co2/3Ni1/3NS–GO), achieving a current density of 10 mA cm−2 at a low overpotential of 259 mV accompanied by a small Tafel slope of 35.7 mV dec−1, surpassing nanocones and 2 D nanosheets, as well as the congeneric heterostructured Co1−xNix hydroxide nanosheets/GO nanoarchitectures (Co1−xNixNS–GO; x=0, 1/2, 1/4, 1) and the commercial RuO2 electrocatalyst. The outstanding activity of Co2/3Ni1/3NS–GO superlattice uncovers the combined merits of 2 D superlattice‐like structure and composition optimization for electrocatalysis, providing a strategy for developing high‐performance electrochemical materials by rational morphology and composition design. [ABSTRACT FROM AUTHOR]

Catalase is an antioxidative enzyme that converts hydrogen peroxide (H2O2) produced by superoxide dismutase from highly reactive superoxide (O2−) to water and oxygen molecules. Although recent findings demonstrate that catalase, autophagy and the nuclear factor κB (NF-κB) signalling pathway are centrally involved in diabetic cardiomyopathy (DCM), the interplay between the three has not been fully characterized. Thus, the mechanism responsible for catalase-mediated protection against heart injury in diabetic mice was investigated in this study, as well as the role of NF-κB-p65 in the regulation of autophagic flux was investigated in this study. Western blot analysis revealed that catalase inhibited NF-κB activity and decreased LC3-II (microtubule-associated protein 1 light chain 3) and beclin-1 (Atg6) expression. Furthermore, up-regulation of autophagy was detrimental for cardiac function in diabetic mice. Catalase overexpression reduced the level of NF-κB subunit in the nucleus, where it initiates autophagy through activation of the key autophagy gene BECN1. To evaluate the role of the NF-κB pathway in diabetes-induced autophagy, Bay11-7082, an NF-κB inhibitor, was injected into diabetic mice, which suppressed NF-κB and attenuated diabetes-induced autophagy and myocardial apoptosis. In agreement with the in vivo results, Bay11-7082 also inhibited high-glucose-induced activation of NF-κB and the up-regulation of LC3-II and beclin-1 expression in H9c2 cells. In addition, high-glucose-induced activation of autophagic flux and apoptosis were largely attenuated by p65 siRNA, suggesting that catalase ameliorates diabetes-induced autophagy, at least in part by increasing the activity of the NF-κB pathway and p65-mediated transcription of BECN1. [ABSTRACT FROM AUTHOR]

Iron-nitrogen-carbon (Fe-N-C) catalysts are considered as the most promising nonprecious metal catalysts for oxygen reduction reactions (ORRs). Their synthesis generally involves complex pyrolysis reactions at high temperature, making it difficult to optimize their composition, pore structure, and active sites. This study reports a simple synthesis strategy by reacting preformed nitrogen-doped carbon scaffolds with iron pentacarbonyl, a liquid precursor that can effectively form active sites with the nitrogen sites, enabling more effective control of the catalyst. The resultant catalyst possesses a well-defined mesoporous structure, a high surface area, and optimized active sites. The catalysts exhibit high ORR activity comparable to that of Pt/C catalyst (40% Pt loading) in alkaline media, with excellent stability and methanol tolerance. The synthetic strategy can be extended to synthesize other metal-N-C catalysts. [ABSTRACT FROM AUTHOR]

Objective The aim of this study was to investigate the change in myocardial strain in swimming athletes before and after high-intensity exercise using two-dimensional strain echocardiography (2DSE) technology. Methods To assess whether the local and overall myocardial function and myocardial injury are accurately measured using 2DSE technology, 15 swimming athletes were selected as research objects. We applied 2DSE technology to track the 2D ultrasound images of the apical four chambers, the apical two chambers, and the apical long axis before and after high-intensity, increasing-load exercise. We recorded indices such as the left ventricular global strain (GS) and the left ventricular segmental wall longitudinal peak systolic strain (PS) in 18 systoles and analyzed the myocardial strain change before and after exercise. Results After high-intensity exercise, the overall myocardial strain decreased, especially the strain of the posterior wall, posterior divider, lateral wall, lower wall, and the basal and middle segments of the anterior wall. The influence of exercise on myocardial strain was greater on the basal and middle segments than on the apical segment. One-time intensive exercise negatively affected the myocardial muscle. Conclusion Myocardial muscles in the apical segment and the myocardial wall were more sensitive to intensive exercise. The 2DSE technology can precisely position the motion-sensitive areas and help locate myocardial injury. [ABSTRACT FROM AUTHOR]

A novel phosphine-catalyzed [4+1] annulation of maleimides with 4,4-dicyano-2-methylenebut-3-enoates has been developed to afford spirocyclic products, and the maleimides serves as C1 synthons. Moreover, a phosphine-catalyzed formal [3+2] annulation between 4,4-dicyano-2-methylenebut-3-enoates and maleic anhydride has been also achieved, and maleic anhydride behaved as a C3 synthon in the reaction, thus efficiently affording the functionalized cyclopentenones. A stable phosphinium-containing zwitterionic compound is the key reactive intermediate in both annulations and was successfully isolated. Plausible mechanisms have been proposed on the basis of control experiments and deuterium-labeling experiments. [ABSTRACT FROM AUTHOR]

A novel Ru0- and RhI-catalyzed noncarbonylative and carbonylative cycloisomerization of readily available 3-alkynyl imine derivatives has been developed to provide 3,4-fused or nonfused pyrrole derivatives efficiently in moderate to excellent yields. The key steps involve the formation of a ruthenium carbenoid intermediate or a rhodacycle intermediate, respectively. In these reactions, CO can serve as a ligand or a reagent. [ABSTRACT FROM AUTHOR]

Highlights: [•] MicroRNA-202 (miR-202) is downregulated in hepatocellular carcinoma (HCC) cells and tissues. [•] Overexpression of miR-202 in HCC cells suppressed cell proliferation and tumorigenicity, while downregulation of miR-202 enhanced the cells’ proliferative capacity. [•] miR-202 suppresses the expression of LRP6 (low-density lipoprotein receptor-related protein 6) by binding to the 3′-untranslated region (UTR) of its mRNA. [•] Silencing the expression of LRP6 is the essential biological function of miR-202 during HCC cell proliferation. [ABSTRACT FROM AUTHOR]

The reaction of methylenecyclopropanes (MCPs) with tetrahydrofuran (THF) proceed smoothly in the presence of AgOC(O)CF3 and electrophilic halogenation reagents to give the corresponding 4-(3-halobut-3-enyloxy)butyl 2,2,2-trifluoroacetate derivatives in moderate yields through dual cleavage of C-C and C-O bonds under mild conditions. [ABSTRACT FROM AUTHOR]

A novel asymmetric [4+2] annulation of vinyl ketones with oxindole-derived α,β-unsaturated imines has been developed in the presence of a multifunctional thiourea-phosphine catalyst derived from a natural amino acid, providing the first phosphine-catalyzed enantioselective synthesis of 2′,3′-dihydro-1′ H-spiro[indoline-3,4′-pyridin]-2-ones in good yields with excellent stereoselectivities under mild conditions. [ABSTRACT FROM AUTHOR]

We demonstrated that MnFe2 O4 spheres could be successfully prepared in large-scale via a facile solvothermal process. The average size of final products over a wide range from 40 to 420 nm was remarkably influenced by the experimental parameters, such as reaction duration, surfactants, and initial concentration of reagents. The structure, size, morphology, and magnetic properties of final products were characterized by X-ray diffraction, transmission electron microscopy, high-resolution transmission electron microscopy, scanning electron microscopy, and vibrating sample magnetometer. The magnetic properties of final products varied with the change of experimental conditions. Preliminary results revealed that this approach could be successfully extended to the preparation of other ferrite compounds. [ABSTRACT FROM AUTHOR]

Gene expression in chloroplasts is regulated by many nuclear-encoded proteins. In this study, we isolated a rice ( Oryza sativa subsp. japonica) mutant osotp51 with significant reduction in photosystem I (PSI). The osotp51 is extremely sensitive to light and accumulates a higher level of reactive oxygen species. Its leaves are almost albino when grown at 40 μmol photons/m2 per s. However, grown at 4 μmol photons/m2 per s, osotp51 has a similar phenotype to the wild-type. 77K chlorophyll fluorescence analysis showed a blue shift in the highest peak emission from PSI in osotp51. In addition, the level of PSI and PSII dimer is dramatically reduced in osotp51. OSOTP 51 encodes a pentatricopeptide repeats protein, homologous to organelle transcript processing 51 in Arabidopsis. Loss-of-function OSOTP51 affects intron splicing of a number of plastid genes, particularly the ycf3 coding a protein involved in the assembly of PSI complex. OSOTP51 is functionally conserved in higher plants. The mutation of osotp51 indirectly leads to a widespread change in the structure and functions of PSI, results in severe photoinhibition, and finally dies, even when grown under very low light intensity. [ABSTRACT FROM AUTHOR]

The sycamore lace bug, Corythucha ciliata (Say) (Hemiptera: Tingidae), is an invasive exotic pest on Platanus trees in China. This study assessed the thermotolerance of C. ciliata in the laboratory. Detailed experiments were conducted on the effects of high temperature (35, 37, 39, 41, 43, and 45 °C), duration of exposure (0.5, 1, 2, 4, 6, and 8 h), and developmental stage (egg, nymph, and adult) on survival of the bug. Meanwhile, the effects of heat hardening on survival at lethal temperature (exposure to 33, 35, 37, 39, and 41 °C for 1 h prior to transfer to 43 °C for 2 h) were also assessed for nymphs and adults. Survival of eggs, nymphs, and adults was not affected by temperatures between 35 and 39 °C, but declined rapidly with increasing duration of exposure (from 0.5 to 8 h) at temperatures ≥41 °C. The lethal temperature that caused mortality of 50% (Ltemp50) of all developmental stages decreased with increasing duration of exposure from 0.5 to 8 h. The Ltemp50 for nymphs was 44.3, 42.0, and 39.0 °C after 0.5, 2, and 8 h exposure, respectively. Thermotolerance was the highest in eggs, followed by adults and then nymphs. Thermotolerance was slightly greater for adult males than for adult females. The ability of nymphs, females, and males to survive exposure to 43 °C for 2 h significantly increased by heat hardening, i.e., by exposure to a non-lethal high temperature for 1 h; the optimal heat-hardening temperature was 37 °C. The results indicate that survival of C. ciliata at heat-shock temperatures depended on both the temperature and the duration of exposure, and the tolerance to heat shock was enhanced by heat hardening. The thermotolerance of C. ciliata may partially explain why C. ciliata has been rapidly spreading on Platanus trees in southern provinces of China. [ABSTRACT FROM AUTHOR]

Human synuclein family consists of α-, β-, and γ-synucleins. Here, we cloned three genes, sncb, sncga and sncgb from zebrafish. They encode β-, γ1-, and γ2-synucleins, respectively. The zSyn-β, zSyn-γ1, and zSyn-γ2 proteins display 69%, 47%, and 50% identity to human β-synuclein and γ-synuclein, respectively. By reverse transcriptase-polymerase chain reaction, we demonstrated that sncb and sncga mRNA were abundant in brain and eye, while sncgb expression was moderate in brain, kidney, ovary and testis. The 1.8-kb 5′-upstream/promoter region of the sncga gene was sufficient to direct green fluorescent protein (GFP) expression in the central nervous system and cranial ganglions. A transgenic line, Tg( sncga:GFP), was generated and its GFP expression is similar to that of endogenous sncga mRNA. Moreover, this line also labels the habenular complex and the domain of GFP expression is larger in the left than in the right habenula. Thus, this line can be used to study sncga gene regulation and for left-right asymmetry study in zebrafish brain. Developmental Dynamics 238:746-754, 2009. © 2009 Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]