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Aqueous zinc‐sulfur (Zn‐S) batteries show great potential for unlocking high energy and safety aqueous batteries. Yet, the sluggish kinetic and poor redox reversibility of the sulfur conversion reaction in aqueous solution challenge the development of Zn‐S batteries. Here, we fabricate a high‐performance Zn‐S battery using highly water‐soluble ZnI2 as an effective catalyst. In situ experimental characterizations and theoretical calculations reveal that the strong interaction between I− and the ZnS nanoparticles (discharge product) leads to the atomic rearrangement of ZnS, weakening the Zn‐S bonding, and thus facilitating the electrochemical oxidation reaction of ZnS to S. The aqueous Zn‐S battery exhibited a high energy density of 742 Wh kg(sulfur)−1 at the power density of 210.8 W kg(sulfur)−1 and good cycling stability over 550 cycles. Our findings provide new insights about the iodide catalytic effect for cathode conversion reaction in Zn‐S batteries, which is conducive to promoting the future development of high‐performance aqueous batteries. [ABSTRACT FROM AUTHOR]

Aqueous batteries with high safety and cost efficiency usually employ metallic cations as charge carriers. Recently, ammonium (NH4+) ion batteries using the nonmetal NH4+ as a charge carrier exhibit distinct electrochemical features from conventional aqueous batteries. Herein, the electrochemical performances of a bimetallic hydroxide material are systematically studied with different charge carriers in the electrolytes, including NH4+, as well as the conventional monovalent metallic cations K+ and Na+, respectively. Electrochemical results indicate that the charge storage process using NH4+ as the working ions exhibits a higher discharge plateau, smaller electrochemical polarization, and larger discharge capacity than that using conventional metallic charge carriers. Experimental characterizations and theoretical calculations suggest that the strong interaction between NH4+ and the electrode material, as well as the low NH4+‐ion diffusion barrier lead to these superior electrochemical features. The assembled NH4+‐ion battery exhibits a good energy density of 123 Wh kg(cathode+anode)−1 at the power density of 480 W kg(cathode+anode)−1. These fundamental findings are important for developing good safety, low‐cost, and high‐energy aqueous batteries with sustainable NH4+ charge carriers. [ABSTRACT FROM AUTHOR]

BACKGROUND: Each Grapholita molesta female only copulates once during its lifetime and thus must maintain the viability of stored eupyrene sperm for male reproductive success. The male ejaculate comprises abundant accessory gland proteins produced by the male accessory gland (AG), and many of which are major effectors for sperm storage and maintenance. RESULTS: Here, we reported that an antioxidant protein, peroxiredoxin 1 (GmolPrx1), secreted by the male AG, is essential for protecting eupyrene sperm from oxidative stress and maintaining their quality during storage in the female bursa copulatrix (BC). Our data showed that GmolPrx1 is highly expressed in the AG of sexually mature males. The GmolPrx1 protein is localized to the cytoplasm of AG cells and delivered to the female BC during mating. Knockdown of GmolPrx1 strongly decreased the fertility of mated females. Additionally, we evaluated oxidative status in the spermatophore of females and found that the content of hydrogen peroxide increased significantly after mating with GmolPrx1 knockdown males. Finally, the quality assessment of eupyrene sperm demonstrated that the plasma membrane integrity, acrosome integrity, and DNA integrity were all severely impaired in the spermatophore of females after mating with GmolPrx1 knockdown males, which may contribute to the fertility decline in males. CONCLUSION: Our current data demonstrated that activities of eupyrene sperm stored in females can be significantly impaired by enhanced oxidative stress through knocking down of GmolPrx1 in males. Our finding thus may further lay new foundations for the control of G. molesta through suppressing their populations by manipulating male reproductive genes. © 2023 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Rechargeable aqueous Zn‐VOx batteries are attracting attention in large scale energy storage applications. Yet, the sluggish Zn2+ diffusion kinetics and ambiguous structure–property relationship are always challenging to fulfil the great potential of the batteries. Here we electrodeposit vanadium oxide nanobelts (VO‐E) with highly disordered structure. The electrode achieves high capacities (e.g. ≈5 mAh cm−2, 516 mAh g−1), good rate and cycling performances. Detailed structure analysis indicates VO‐E is composed of integrated amorphous‐crystalline nanoscale domains, forming an efficient heterointerface network in the bulk electrode, which accounts for the good electrochemical properties. Theoretical calculations indicate that the amorphous‐crystalline heterostructure exhibits the favorable cation adsorption and lower ion diffusion energy barriers compared to the amorphous and crystalline counterparts, thus accelerating charge carrier mobility and electrochemical activity of the electrode. [ABSTRACT FROM AUTHOR]

Background: Perimitral atrial tachycardia (PMAT) is the most frequent type of iatrogenic atrial tachycardia (AT) after atrial fibrillation (AF) ablation. Vein of Marshall ethanol infusion (EIVOM) is a promising technique in mitral isthmus (MI) ablation. Methods: A total of 165 patients with PMAT were divided into three groups according to ablation strategies, including RF only group (n = 89), RF‐EIVOM group (initial RF ablation with adjunctive EIVOM, n = 28), and EIVOM‐RF group (first‐step EIVOM with touch‐up RF ablation, n = 48). Acute and follow‐up procedure outcomes were evaluated. Results: PMAT terminated in 89.9%, 89.3%, and 93.7% of patients in RF only, RF‐EIVOM and EIVOM‐RF groups, respectively (p =.715), with complete MI block achieved in 80.9%, 89.3%, and 95.8% of patients (EIVOM‐RF vs. RF only, p =.012). First‐step utilization of EIVOM was associated with a significant shortening of RF ablation time at MI (EIVOM‐RF 2.1 ± 1.3 min, RF only 7.9 ± 5.9 min, RF‐EIVOM 6.8 ± 5.8 min; p <.001) and a decrease in the proportion of patients need ablation within coronary sinus (CS, EIVOM‐RF 14.6%, RF only 61.8%, RF‐EIVOM 64.3%; p <.001). After a mean follow‐up of 12.1 ± 6.2 months, AF/AT recurred in 39 (43.8%), 6 (21.4%), and 12 (25.0%) patients in RF only, RF‐EIVOM, and EIVOM‐RF group (RF‐EIVOM vs. RF only, p =.026; EIVOM‐RF vs. RF only, p =.022). Conclusions: EIVOM was associated with an enhanced acute MI block rate as well as reduced AF/AT recurrence. First‐step utilization of EIVOM promises to significantly simplify the RF ablation process. PMAT is the most common type of iatrogenic AT after AF ablation procedures. EIVOM contributed to a higher acute MI block rate and lower arrhythmia recurrence risk during follow‐up. First‐step utilization of EIVOM significantly reduced the need for radiofrequency ablation at MI and inside CS with the advantage of creating a homogenous, transmural lesion and eliminating epicardial connections. [ABSTRACT FROM AUTHOR]

Ammonium (NH4+) ion as charge carrier is attracting attention in aqueous batteries. Yet, most NH4+ host materials are still limited by the relatively low capacities. Here, we fabricated a manganese phosphate (MP‐20) for NH4+ ion storage. MP‐20 displays a high capacity of 299.6 mAh g−1 at 1 A g−1 in ammonium acetate (NH4Ac) electrolyte, outperforming other reported NH4+ host materials. Spectroscopy studies suggest a new NH4+/H+ co‐insertion mechanism. We surprisingly discover that the NH4Ac electrolyte plays an important role in improving the charge storage capability of the materials. Experimental and computational results indicate acetate ions can form coordination bonds with the Mn atoms, tailoring the electronic structure of the Mn atoms and the surrounding O atoms, and therefore facilitating the NH4+ storage process. Our findings provide a new NH4+ host material and propose the important role of the electrolyte‐electrode coordination effect in aqueous ammonium batteries. [ABSTRACT FROM AUTHOR]

Transition metal layered double hydroxides (LDHs) are widely used as high‐performance cathode materials for aqueous alkaline zinc (Zn) batteries. Yet, the strongly alkaline electrolytes may lead to undesirable rechargeability of the alkaline devices and environmental issues. Herein, as a research prototype, CoNi LDH material is designed with abundant H vacancies using electrochemical methods (denoted as CoNi LDH(v)). As a Zn‐ion battery cathode, CoNi LDH(v) exhibits promising electrochemical performances in mild ZnSO4 electrolyte, such as a good specific capacity of 185 mAh g−1 at the current density of 1.2 A g−1, a high average discharge potential of 1.6 V versus Zn2+/Zn, and a large energy density of 296.2 Wh kg−1 at the power density of 1894 W kg−1, outperforming most of the cathode materials for aqueous Zn‐ion batteries. Experimental and computational results indicate that the introduced H vacancies in the double hydroxide matrix induce the improved electronic conductivity and cation adsorption thermodynamics, endowing the double hydroxides with good electrochemical activity for reversible cation insertion. Structural and spectroscopy studies identify that CoNi LDH(v) experiences reversible H+/Zn2+ co‐intercalation mechanism in an aqueous ZnSO4 electrolyte. As far as it is known, it is the first report on transition‐metal‐based double hydroxides used for mild aqueous Zn‐ion batteries. [ABSTRACT FROM AUTHOR]

BACKGROUND: High temperatures will occur more frequently with global warming, with potential impacts on the efficacy of biological control agents. Heat shock proteins (HSPs) are induced by high temperature, but their possible roles in pest resistance to entomopathogens remain unexplored. We investigated the effects of high temperature (35 °C) on Helicoverpa armigera resistance to H. armigera nucleopolyhedrovirus (HearNPV) and the putative roles of HSPs in this process. RESULTS: Even short periods (24 h) of high temperature (35 °C) reduced mortality in HearNPV‐infected H. armigera larvae. Sustained 35 °C exposure significantly shortened developmental time, and increased fresh weight and locomotor activity in infected larvae. Moreover, high temperature inhibited virus replication and thickened the epidermis of H. armigera, resulting in reduced spread of infection from cadavers. Real‐time polymerase chain reaction (PCR) analysis showed that expression of 11 HSP genes was altered by the 35 °C treatment, and that mostly small heat shock protein (sHSP) genes were up‐regulated, the same sHSPs were induced when larvae were infected with HearNPV. Finally, RNA interference (RNAi) suppression of these sHSPs showed that only Hsp24.91 and Hsp21.8 diminished H. armigera defensive responses to HearNPV infection. CONCLUSION: Even short periods of exposure to high temperature can significantly reduce susceptibility of H. armigera larvae to HearNPV by stimulating the production of sHSPs which enhance immune responses, with important implications for the use of entomopathogens as biological control agents under global warming scenarios. © 2022 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Mn‐based materials for aqueous energy storage are reaching the capacity ceiling due to the limited Mn4+/Mn3+ redox. The disproportionation of Mn3+ often occurs, forming soluble Mn2+ and thus leading to severer capacity decays. Here, an amorphous manganese phosphate material [AMP, Na1.8Mn4O1.4(PO4)3] is fabricated using an electrochemical method for the first time. Benefitting from the open framework and the insoluble nature of Mn2+ in AMP, the Mn3+/Mn2+ and Mn4+/Mn3+ redox couples can participate in the charge storage processes. The AMP electrode shows a high capacity of 253.4 mAh g−1 (912.4 F g−1 or 912.4 C g−1) at the current density 1 A g−1 and good rate capability. Experimental results indicate AMP experiences a mixed charge storage mechanism (i.e., cation intercalation and conversion reactions) in Na2SO4 electrolyte. Besides, electrolyte engineering can effectively prevent the decomposition of AMP during cycling test, achieving capacity retention of 97% in 5000 cycles. Importantly, AMP can accommodate different cations (e.g., Mg2+, Ca2+, etc.), exhibiting great potential for aqueous energy storage. [ABSTRACT FROM AUTHOR]

NH4+ ions as charge carriers show potential for aqueous rechargeable batteries. Studied here for the first time is the NH4+‐storage chemistry using electrodeposited manganese oxide (MnOx). MnOx experiences morphology and phase transformations during charge/discharge in dilute ammonium acetate (NH4Ac) electrolyte. The NH4Ac concentration plays an important role in NH4+ storage for MnOx. The transformed MnOx with a layered structure delivers a high specific capacity (176 mAh g−1) at a current density of 0.5 A g−1, and exhibits good cycling stability over 10 000 cycles in 0.5 M NH4Ac, outperforming the state‐of‐the‐art NH4+ hosting materials. Experimental results suggest a solid‐solution behavior associated with NH4+ migration in layered MnOx. Spectroscopy studies and theoretical calculations show that the reversible NH4+ insertion/deinsertion is accompanied by hydrogen‐bond formation/breaking between NH4+ and the MnOx layers. These findings provide a new prototype (i.e. layered MnOx) for NH4+‐based energy storage and contributes to the fundamental understanding of the NH4+‐storage mechanism for metal oxides. [ABSTRACT FROM AUTHOR]

Conducting polymers (CPs) have been widely studied for electrochemical energy storage. However, the dopants in CPs are often electrochemically inactive, introducing "dead‐weight" to the materials. Moreover, commercial‐level electrode materials with high mass loadings (e.g., >10 mg cm−2) often encounter the problems of inferior electrical and ionic conductivity. Here, a redox‐active poly‐counterion doping concept is proposed to improve the electrochemical performance of CPs with ultra‐high mass loadings. As a study prototype, heptamolybdate anion (Mo7O246−) doped polypyrrole (PPy) is synthesized by electro‐polymerization. A 2 mm thick PPy electrode with mass loading of ≈192 mg cm−2 reaches a record‐high areal capacitance of ≈47 F cm−2, competitive gravimetric capacitance of 235 F g−1, and volumetric capacitance of 235 F cm−3. With poly‐counterion doping, the dopants also undergo redox reactions during charge/discharge processes, providing additional capacitance to the electrode. The interaction between polymer chains and the poly‐counterions enhances the electrical conductivity of CPs. Besides, the poly‐counterions with large steric hindrance could act as structural pillars and endow CPs with open structures for facile ion transport. The concept proposed in this work enriches the electrochemistry of CPs and promotes their practical applications. [ABSTRACT FROM AUTHOR]

Background: Optimal antithrombotic therapy following left atrial appendage closure (LAAC) with the Watchman occluder remains uncertain. This study retrospectively compared clinical outcomes of a 3‐month dual antiplatelet therapy (DAPT group) and a protocol of anticoagulation plus aspirin for 45 days followed by DAPT for 6 months (ACT group) after LAAC with the Watchman device. Methods: Of two Watchman registries (Coburg and Lichtenfels hospitals, Germany), 220 and 304 consecutive patients with successful LAAC were included. Patients in Coburg hospital received DAPT while they received ACT in Lichtenfels. After a 1:1 propensity score matching, 174 (DAPT) versus 174 (ACT) patients were compared by use of the primary efficacy endpoint of thromboembolic events and cardiovascular/unexplained death, the primary safety endpoint of nonprocedural related major bleeding events at follow‐up, and the combined hazard endpoint, a composite of all above‐mentioned hazards. Results: The mean age 77.5 ± 7.2 (DAPT) versus 77.3 ± 7.1 (ACT) years, CHA2DS2‐VASc score 4.6 ± 1.5 versus 4.7 ± 1.6, and HAS‐BLED score 3.3 ± 0.8 versus 3.3 ± 0.8 were similar. After 12 months, the clinical efficacy (13/174, 7.4% [DAPT] vs 11/174, 6.3% [ACT]; hazard ratio [HR], 0.84; 95% confidence interval [CI], 0.38‐1.86; P =.66) and safety (6/174, 3.4% vs 8/174, 4.5%; HR, 0.86; 95% CI, 0.29‐2.56; P =.79) as well as the combined hazard endpoint (18/174, 10.3% vs 18/174, 10.3%; HR,1.01; 95% CI, 0.53‐1.95; P =.97) were comparable. Conclusions: This study suggests comparable efficacy and safety of 3‐month DAPT versus 6 weeks ACT plus aspirin following LAAC with the Watchman. [ABSTRACT FROM AUTHOR]

Various cathode materials have been proposed for high‐performance rechargeable batteries. Vanadyl phosphate is an important member of the polyanion cathode family. VOPO4 has seven known crystal polymorphs with tunneled or layered frameworks, which allow facile cation (de)intercalations. Two‐electron transfer per formula unit can be realized by using VV/VIV and VIV/VIII redox couples. The electrochemical performance is closely related to the structures of VOPO4 and the types of inserted cations. This Review outlines the crystal structures of VOPO4 polymorphs and their lithiated phases. The research progress of vanadyl phosphate cathode materials for different energy storage systems, including lithium‐ion batteries, sodium‐ion batteries, potassium‐ion batteries, multivalent batteries, and supercapacitors, as well as the related mechanism investigations are summarized. It is hoped that this Review will help with future directions of using vanadyl phosphate materials for energy storage. [ABSTRACT FROM AUTHOR]

Introduction: The LAmbre (LifeTech Scientific, Shenzhen, China) is a novel occluder for left atrial appendage closure (LAAC) in patients with atrial fibrillation. This study compares late clinical outcomes of LAmbre and the established Amplatzer devices (Abbott, St Paul, MN). Methods: Between 2012 and 2018, 265 consecutive patients underwent LAAC with LAmbre and Amplatzer devices at a single center. After a 3:1 propensity score matching, 40 (LAmbre) vs 107 (Amplatzer) patients were compared by the primary efficacy endpoint of all‐cause stroke, systemic embolism and cardiovascular/unexplained death, the primary safety endpoint of major periprocedural complications and major bleeding events at follow‐up, and the combined hazard endpoint, a composite of all the above‐mentioned hazards. Results: The mean age 75.6 ± 8.9 (LAmbre) vs 75.5 ± 9.0 (Amplatzer) years, CHA2DS2‐VASc score 4.8 ± 1.7 vs 4.8 ± 1.7 and HAS‐BLED score 3.1 ± 0.9 vs 3.2 ± 0.8 were similar. After 3.6 ± 1.9 vs 2.5 ± 1.4 years, the clinical efficacy (12/146, 8.2% [LAmbre] vs 28/266, 10.5% [Amplatzer]; hazard ratio [HR], 0.73; 95% confidence interval [CI], 0.38‐1.40; P =.34) and safety (5/146, 3.4% vs 14/266, 5.3%; HR, 0.47; 95% CI, 0.14‐1.6; P =.22), as well as the combined hazard endpoint (15/146, 10.3% vs 36/266, 13.6%; HR, 0.67; 95% CI, 0.36‐1.25; P =.21) were comparable. Conclusion: In the presented report, in patients with nonvalvular atrial fibrillation, the LAmbre offered similar long‐term efficacy and safety in comparison to Amplatzer devices. [ABSTRACT FROM AUTHOR]

VOPO4⋅x H2O has been proposed as a cathode for rechargeable aqueous zinc batteries. However, it undergoes significant voltage decay in conventional Zn(OTf)2 electrolyte. Investigations show the decomposition of VOPO4⋅x H2O into VOx in the electrolyte and voltage drops after losing the inductive effect from polyanions.PO43− was thus added to shift the decomposition equilibrium. A high concentration of cheap, highly soluble ZnCl2 salt in the electrolyte further prevents VOPO4⋅x H2O dissolution. The cathode shows stable capacity and voltage retentions in 13 m ZnCl2/0.8 m H3PO4 aqueous electrolyte, in direct contrast to that in Zn(OTf)2 where the decomposition product VOx provides most electrochemical activity over cycling. Sequential H+ and Zn2+ intercalations into the structure are revealed, delivering a high capacity (170 mAh g−1). This work shows the potential issue with polyanion cathodes in zinc batteries and proposes an effective solution using fundamental chemical principles. [ABSTRACT FROM AUTHOR]

Circadian clock genes in peripheral tissues usually play an important role in regulating the circadian rhythms. Light is the most important environmental signal for synchronizing endogenous rhythms with the daily light‐dark cycle, and compound eyes are known as the principal circadian photoreceptor for photic entrainment in most moths. However, there is little evidence for circadian timing in compound eyes. In the current study, we isolated the timeless gene, designated Ha‐tim (GenBank accession number: KM233162), from the cotton bollworm Helicoverpa armigera. Ha‐tim and period (Ha‐per) showed low messenger RNA levels in the compound eyes compared to the other tested adult organs. Ha‐tim and Ha‐per transcript levels were dependent on an endogenous rhythm that fluctuated over a daily cycle in the compound eyes and heads. The cycles of Ha‐tim and Ha‐per transcript levels followed similar time courses, and identical expression patterns of the two genes were observed in the compound eyes and heads. Ha‐tim and Ha‐per were down‐regulated in the compound eyes after light exposure, copulation and starvation. These results indicated that Ha‐tim and Ha‐per transcript levels were regulated by endogenous and exogenous factors. Our study helped to improve our understanding of the circadian clock machinery in compound eyes and other peripheral tissues. [ABSTRACT FROM AUTHOR]

Abstract: Design and synthesis of metal oxide‐based pseudocapacitive materials to simultaneously achieve high mass loading (e.g., up to 10 mg cm−2) and excellent rate capability for electrochemical capacitors is a long‐lasting challenge. These two characteristics are usually mutually exclusive due to the poor ion diffusion kinetics of most metal oxides. Here, a glucose‐assisted hydrothermal method to prepare thick hematite film (>1 µm) with engineerable mesopore size through controlled variation of glucose concentration is demonstrated. The capability of controlling the size of mesopores offers a unique opportunity to investigate for the first time the interplay between mesopore size and electrochemical performance of hematite films. The hematite film with an average mesopore size of 3 nm at an ultrahigh loading of 10 mg cm−2 exhibits an areal capacitance of 1502 mF cm−2 at 1 mA cm−2, and retains 871.2 mF cm−2 at 50 mA cm−2. Such performance, to the best of the authors' knowledge, is at the top of the reported hematite electrodes with comparable or even lower mass loadings. The strategy demonstrated herein may be extended to fabricate diverse types of mesoporous metal oxide architectures with improved ion diffusion kinetics, which is critical for a broad range of devices for energy storage and conversion. [ABSTRACT FROM AUTHOR]

Abstract: Vanadium oxide is a promising pseudocapacitive electrode, but their capacitance, especially at high current densities, requires improvement for practical applications. Herein, a VOx@MoO3 composite electrode is constructed through a facile electrochemical method. Fourier transform infrared spectroscopy and X‐ray photoelectron spectroscopy demonstrate a modification on the chemical environment and electronic structure of VOx upon the effective interaction with the thin layer of MoO3. A careful investigation of the electrochemical impedance spectroscopy data reveals much enhanced power capability of the composite electrode. More charge storage sites will also be created at/near the heterogeneous interface. Due to those synergistic effects, the VOx@MoO3 electrode shows excellent electrochemical performance. It provides a high capacitance of 1980 mF cm−2 at 2 mA cm−2. Even at the high current density of 100 mA cm−2, it still achieves 1166 mF cm−2 capacitance, which doubles the sum of single electrodes. The MoO3 layer also helps to prevent VOx structure deformation, and 94% capacitance retention over 10 000 cycles is obtained for the composite electrode. This work demonstrates an effective strategy to induce interactions between heterogeneous components and enhance the electrochemical performance, which can also be applied to other pseudocapacitive electrode candidates. [ABSTRACT FROM AUTHOR]

Abstract: Electrode materials with low cost, large theoretical capacity, and fast ion/electron transport rate are highly desirable for capacitive applications. Pseudocapacitive iron oxide materials (e. g., Fe2O3, Fe3O4) satisfy the first two aspects, but are electrically/ionically insulating, hindering their practical applications in energy storage. Here, hybrid mesoporous iron oxide (Fe2O3/Fe3O4) materials are integrated with a three‐dimensional electrochemically exfoliated graphite substrate (EG) using an electrodeposition coupled with a post‐chemical transition strategy. The hybrid Fe2O3/Fe3O4 materials on EG exhibit an ultrahigh specific capacitance of 1530 F g−1 at current density of 1 A g−1. This material with such high capacitance ranks on the top of the reported iron oxide materials for capacitive applications. In addition, the assembled device with EG@Fe2O3/Fe3O4 as anode can deliver a high gravimetric energy density of 21.6 Wh kg−1 at a power density of 225 W kg−1, based on the total mass of the two electrodes (including the mass of the current collectors). This system can power various electronic devices, suggesting its great potential for energy storage applications. [ABSTRACT FROM AUTHOR]

The reaction of Cu(NO3)2·3H2O with 2,4′-oxybis(benzoic acid) and 4,4′-bipyridine under hydrothermal conditions produced a new mixed-ligand two-dimensional copper(II) coordination polymer, namely poly[[(μ-4,4′-bipyridine-κ2 N, N′)[μ-2,4′-oxybis(benzoato)-κ4 O2, O2′: O4, O4′]copper(II)] monohydrate], {[Cu(C14H8O5)(C10H8N2)]·H2O} n, which was characterized by elemental analysis, IR spectroscopy, thermogravimetric analysis and single-crystal X-ray diffraction. The X-ray diffraction crystal structure analysis reveals that the CuII ions are connected to form a two-dimensional wave-like network through 4,4′-bipyridine and 2,4′-oxybis(benzoate) ligands. The two-dimensional layers are expanded into a three-dimensional supramolecular structure through intermolecular O-H...O and C-H...O hydrogen bonds. Furthermore, magnetic susceptibility measurements indicate that the complex shows weak antiferromagnetic interactions between adjacent CuII ions. [ABSTRACT FROM AUTHOR]

BACKGROUND Excessive accumulation of oxalate in numerous vegetables adversely affects their quality as food. While it is known that nitrate could effectively stimulate oxalate accumulation in many vegetables, little information is available about the mechanism of nitrate-induced oxalate accumulation. In this study, we examined the association of oxalate synthesis with nitrate uptake and assimilation in two genotypes of spinach ( Spinacia oleracea L.), Heizhenzhu and Weilv. RESULTS Increasing nitrate levels resulted in enhanced synthesis of oxalate, as well as increased root uptake of nitrate and leaf activities of nitrate reductase ( NR) and glutamine synthetase ( GS) for both genotypes. Correlation analysis revealed that oxalate accumulation in spinach leaves was positively related with rate of nitrate uptake by roots, as well as leaf activities of NR and GS. Addition of plasmalemma H+- ATPase inhibitor sodium vanadate ( Na3VO4) significantly decreased leaf oxalate accumulation in both genotypes. Presence of NR or GS inhibitors led to reduction of leaf oxalate contents, GS/ NR activities and decreased nitrate uptake rate. Significantly higher levels of nitrate root uptake, leaf NR and GS activities were observed in the high-oxalate genotype Heizhenzhu than in Weilv. CONCLUSION Oxalate synthesis in leaves of spinach is not only positively associated with root uptake of nitrate, but also with its assimilation within the plants. © 2014 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Polypyrrole (PPy) is a promising pseudocapacitive material for supercapacitor electrodes. However, its poor cycling stability is the major hurdle for its practical applications. Here a two-prong strategy is demonstrated to stabilize PPy film by growing it on a functionalized partial-exfoliated graphite (FEG) substrate and doping it with β-naphthalene sulfonate anions (NS−). The PPy electrode achieves a remarkable capacitance retention rate of 97.5% after cycling between −0.8 and 0 V versus saturated calomel electrode for 10 000 cycles. Moreover, an asymmetric pseudocapacitor using the stabilized PPy film as anode also retains 97% of capacitance after 10 000 cycles, which is the best value reported for PPy-based supercapacitors. The exceptional stability of PPy electrode can be attributed to two factors: 1) the flexible nature of FEG substrate accommodates large volumetric deformation and 2) the presence of immobile NS− dopants suppresses the counterion drain effect during charge-discharge cycling. [ABSTRACT FROM AUTHOR]

To improve the photocatalytic properties of coordination polymers under irradiation in the visible-light region, coordination polymer nanobelts (CPNB) were loaded on functional carbon fiber (FCF) through the use of a simple colloidal blending process. The resulting coordination polymer nanobelt loaded functional carbon fiber composite material (CPNB/FCF) exhibited dramatically improved photocatalytic activity for the degradation of rhodamine B (RhB) under visible-light irradiation. Optical and electrochemical methods illustrated the enhanced photocatalytic activity of CPNB/FCF originated from high separation efficiency of photogenerated electrons and holes on the interface of CPNB and FCF, which was produced by the synergy effect between them. In the composite material, the role of FCF could be described as photosensitizer and good electron transporter. For FCF, the number of functional groups on its surface has a significant influence on the photocatalytic performance of the resulting CPNB/FCF composite material, and an ideal FCF carrier was obtained as a highly efficient CPNB/FCF photocatalyst. CPNB/FCF showed outstanding stability during the degradation of rhodamine B (RhB); thus, the material is suitable for use as a photocatalyst in the treatment of organic dyes in water. [ABSTRACT FROM AUTHOR]

BACKGROUND Quality-associated problems, such as excessive in planta accumulation of oxalate, often arise in soillessly cultivated spinach ( Spinacia oleracea). Maintaining a higher level of ammonium (NH4+) compared to nitrate (NO3−) during the growth period can effectively decrease the oxalate content in hydroponically cultivated vegetables. However, long-term exposure to high concentrations of NH4+ induces toxicity in plants, and thus decreases the biomass production. Short-term application of NH4+ before harvesting in soilless cultivation may provide an alternative strategy to decrease oxalate accumulation in spinach, and minimise the yield reduction caused by NH4+ toxicity. RESULT The plants were pre-cultured in 8 mmol L−1 NO3− nutrient solution. Next, 6 days before harvest, the plants were transferred to a nutrient solution containing 4 mmol L−1 NO3− and 4 mmol L−1 NH4+. This new mix clearly reduced oxalate accumulation, increased levels of several antioxidant compounds, and enhanced antioxidant capacity in the edible parts of spinach plants, but it did not affect biomass production. However, when the 8 mmol L−1 NO3− was shifted to either nitrogen-free, 4 mmol L−1 NH4+ or 8 mmol L−1 NH4+ treatments, although some of the quality indexes were improved, yields were significantly reduced. CONCLUSIONS Short-term alteration of nitrogen supply prior to harvest significantly affects quality and biomass of spinach plants, and we strongly recommend to simultaneously use NO3− and NH4+ in hydroponic cultivation, which improves vegetable quality without decreasing biomass production. © 2013 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

The cotton aphid, Aphis gossypii Glover, is a wing-dimorphic species, which causes globally important agricultural losses. In this present study, we compared the biochemical basis of wing polymorphism in A. gossypii with respect to trade-off of energy resources, including glycogen, trehalose, lipids (total lipid, triglyceride and phospholipid), free fatty acids, and soluble protein between dispersal and reproduction morphs during the wing-bud nymph and adulthood. Total lipid, triglyceride and free fatty acids were significantly higher in winged versus wingless morphs at 12 h of adulthood, the period during which alates are able to fly. By contrast, the wingless morph contained more glycogen than the winged morph from the 4th nymphal stage to adulthood. Trehalose content in the wingless morph was also higher than that in the winged morph during the 3rd and 4th nymphal stages, but vice versa at 12 h of adulthood. Finally, soluble protein content increased from nymphs to adults and was higher during adulthood in aptera versus alate. Whole-body water content in 12-h adults was significantly higher in apterae than that in alatae. These results indicate significant physiological differences between morphs related to specialization for flight. [ABSTRACT FROM AUTHOR]

A retraction of the article "Prospective randomized comparison between upgraded "2C3L" versus PVI approach for catheter ablation of persistent atrial fibrillation: PROMPT-AF trial design" in a 2021 issue is presented.

Keywords: cathode materials; polyanions; rechargeable batteries; supercapacitors; vanadyl phosphate EN cathode materials polyanions rechargeable batteries supercapacitors vanadyl phosphate 1 1 1 07/04/20 20200702 NES 200702 B The vanadyl phosphate materials b have various crystal structures, which allow reversible cation (de)intercalation. Cathode materials, polyanions, rechargeable batteries, supercapacitors, vanadyl phosphate. [Extracted from the article]

Commercial electrodes need high mass loadings to realize superior energy and power densities. However, good electrochemical properties are usually achieved in the electrodes with ultrathin active materials (e.g., <1 mg cm−2). Good performance and high mass loading are often mutually exclusive characteristics. Herein, a unique 3D exfoliated carbon paper (EC) is demonstrated using a facile electrochemical method to support high mass loading MnO2 materials. The 3D‐interconnected graphene/graphite network, highly porous structure, as well as the strong interaction between the active materials and the substrate, allow efficient charge transport in the composite electrode, addressing the traditional limitations in high mass loading electrodes. The deposited MnO2 (mass loading: 9.5–10 mg cm−2) achieves a remarkable capacitive performance with high areal and gravimetric capacitances of 5.1 F cm−2 and 537 F g−1, respectively. A Zn–MnO2 battery is also assembled using MnO2/EC as the cathode. An excellent specific capacity of 368 mAh g−1 is also delivered. This MnO2/EC outperforms most of the reported MnO2‐based electrodes with similar loadings for capacitive and Zn‐ion battery applications, highlighting the great application potential of the 3D carbon paper support in electrochemical energy storage. [ABSTRACT FROM AUTHOR]

Manganese (Mn) oxides are promising cathode materials for rechargeable aqueous Zn‐ion batteries. However, the Mn dissolution in weakly acidic electrolytes always hinders the development of better aqueous Zn–Mn batteries. Herein, a hydroxylated manganese oxide cathode material (H‐MnO2) is fabricated using an electrochemical method for stable aqueous Zn–Mn batteries without relying on the Mn2+ electrolyte additives. The partial hydroxylation of the oxides leads to charge redistribution of the material, changing the reaction thermodynamics and kinetics. Theoretical simulation suggests that the hydroxylation of manganese oxide promotes both Zn2+ adsorption thermodynamics and diffusion kinetics on the surface of H‐MnO2 but weakens the interaction between H+ and the electrode. Therefore, Zn2+ ions can be more reactive with the hydroxylated manganese oxide than H+ ions. Experimental results show that the Zn2+ insertion mechanism dominates the charge storage process of H‐MnO2, and the H+‐induced Mn dissolution reaction is effectively alleviated. Importantly, H‐MnO2 exhibits good cycling stability with 95% capacity retention over 5000 cycles at the current density of 3.8 A g−1 in the ZnSO4 electrolyte, outperforming the state‐of‐the‐art aqueous Zn–Mn batteries, even those with Mn2+ electrolyte additives. The findings provide new insights for designing stable manganese oxide cathodes in aqueous Zn–Mn batteries. [ABSTRACT FROM AUTHOR]