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Masspersonal communication has emerged as a compelling alternative persuasive approach in response to the widespread use of social media. It is crucial to comprehend how observing online interpersonal interactions regarding the fear appeal of climate change can foster pro-environmental behaviors among users. This study examines the effects of vicarious message interactivity in promoting actions against climate change and the underlying mechanisms behind this effect. The results of an online experiment conducted in China (N = 236) revealed that psychological reactance and message elaboration mediated the effects of vicarious message interactivity on behavioral intention in a serial indirect effect. In comparison to static fear appeal, interactive fear appeal proves effective in reducing psychological reactance, promoting message elaboration, and ultimately increasing intention to take actions against climate change. Our findings not only contribute to the literature on interactive communication but also provide insights for environmental-health campaigns on social media.
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Mudança Climática , Medo , Comunicação em Saúde , Intenção , Comunicação Persuasiva , Mídias Sociais , Humanos , Masculino , Feminino , China , Mídias Sociais/estatística & dados numéricos , Comunicação em Saúde/métodos , Adulto Jovem , Adulto , Promoção da Saúde/métodosRESUMO
Bacteriophages have been used across various fields, and the utilization of CRISPR/Cas-based genome editing technology can accelerate the research and applications of bacteriophages. However, some bacteriophages can escape from the cleavage of Cas protein, such as Cas9, and decrease the efficiency of genome editing. This study focuses on the bacteriophage T7, which is widely utilized but whose mechanism of evading the cleavage of CRISPR/Cas9 has not been elucidated. First, we test the escape rates of T7 phage at different cleavage sites, ranging from 10 -2 to 10 -5. The sequencing results show that DNA point mutations and microhomology-mediated end joining (MMEJ) at the target sites are the main causes. Next, we indicate the existence of the hotspot DNA region of MMEJ and successfully reduce MMEJ events by designing targeted sites that bypass the hotspot DNA region. Moreover, we also knock out the ATP-dependent DNA ligase 1. 3 gene, which may be involved in the MMEJ event, and the frequency of MMEJ at 4. 3 is reduced from 83% to 18%. Finally, the genome editing efficiency in T7 Δ 1. 3 increases from 20% to 100%. This study reveals the mechanism of T7 phage evasion from the cleavage of CRISPR/Cas9 and demonstrates that the special design of editing sites or the deletion of key gene 1. 3 can reduce MMEJ events and enhance gene editing efficiency. These findings will contribute to advancing CRISPR/Cas-based tools for efficient genome editing in phages and provide a theoretical foundation for the broader application of phages.
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Bacteriófago T7 , Sistemas CRISPR-Cas , Edição de Genes , Edição de Genes/métodos , Bacteriófago T7/genética , DNA Ligases/genética , DNA Ligases/metabolismo , Proteínas Virais/genética , Proteínas Virais/metabolismo , Genoma ViralRESUMO
Harvesting wind energy from the environment and integrating it with the internet of things and artificial intelligence to enable intelligent ocean environment monitoring are effective approach. There are some challenges that limit the performance of wind energy harvesters, such as the larger start-up torque and the narrow operational wind speed range. To address these issues, this paper proposes a wind energy harvesting system with a self-regulation strategy based on piezoelectric and electromagnetic effects to achieve state monitoring for unmanned surface vehicles (USVs). The proposed energy harvesting system comprises eight rotation units with centrifugal adaptation and four piezoelectric units with a magnetic coupling mechanism, which can further reduce the start-up torque and expand the wind speed range. The dynamic model of the energy harvester with the centrifugal effect is explored, and the corresponding structural parameters are analyzed. The simulation and experimental results show that it can obtain a maximum average power of 23.25 mW at a wind speed of 8 m/s. Furthermore, three different magnet configurations are investigated, and the optimal configuration can effectively decrease the resistance torque by 91.25% compared with the traditional mode. A prototype is manufactured, and the test result shows that it can charge a 2200 µF supercapacitor to 6.2 V within 120 s, which indicates that it has a great potential to achieve the self-powered low-power sensors. Finally, a deep learning algorithm is applied to detect the stability of the operation, and the average accuracy reached 95.33%, which validates the feasibility of the state monitoring of USVs.
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The innovation of this study was to develop a novel biodegradable intelligent packaging based on chitosan/fucoidan combined with different amounts (1, 3 and 5 wt% on chitosan basis) of coleus grass (Plectranthus scutellarioides) leaves anthocyanins (CGL) to monitor the spoilage of salmon (Salmo salar L.). The addition of fucoidan improved the barrier and mechanical properties of the chitosan films (CS) due to hydrogen bonds and intermolecular electrostatic interactions. Moreover, the addition of CGL not only improved the physical properties but also improved the biological activity of chitosan/fucoidan film (CF). The DPPH and ABTS radical scavenging activity of CF contained 5 wt% CGL was 1.83 and 1.75 times than CF, respectively. The inhibition zone size of CF films containing 5 wt% CGL (CF-5%CGL) was approximately 2.04 (Escherichia coli) and 2.16 (Staphylococcus aureus) times higher than that of CF. Moreover, CF-CGL displayed obvious color changes in different pH environments and is highly sensitive to ammonia gas. The CF-CGL has visible color changes during the monitoring of salmon spoilage and extended the shelf life of salmon. According to our findings, CF-CGL film might be employed as a possible intelligent packaging material for monitoring and preserving salmon in the future.
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Quitosana , Coleus , Plectranthus , Salmo salar , Animais , Quitosana/química , Antocianinas/química , Embalagem de Alimentos , Poaceae , Concentração de Íons de HidrogênioRESUMO
Active films were developed based on chitosan, esterified chitin nanofibers and rose essential oil (REO). The joint effects of chitin nanofibers and REO on structure and physicochemical properties of chitosan film were investigated. Scanning electron microscopy and Fourier transform infrared spectroscopy showed that the chitin nanofibers and REO had significant effects on the morphology and chemical structure of chitosan composite films. The negatively charged esterified chitin nanofibers formed a compact network structure through intermolecular hydrogen bonding and electrostatic interactions with the positively charged chitosan matrix. Chitin nanofibers and REO synergistically enhanced the water resistance, mechanical properties and UV resistance of chitosan-based films, but the addition of REO increased the oxygen permeability. Furthermore, the addition of REO enhanced the inhibition of ABTS and DPPH free radicals and microorganisms by chitosan-based film. Therefore, chitosan/chitin nanofiber-based active films containing REO as food packaging materials can potentially provide protection to extend food shelf life.
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The aim of this study was to develop a novel active packaging using chitosan (CS) and esterified chitin nanofibers (CF) combined with different contents (1, 2 and 4 wt% on CS basis) of scallion flower extract (SFE) to protect banana samples. The addition of CF significantly improved the barrier and mechanical properties of the CS films (p < 0.05) due to hydrogen bonds and electrostatic interactions. Moreover, the addition of SFE not only improved the physical properties of the CS film but also improved the CS film biological activity. The oxygen barrier property and antibacterial ability of CF-4%SFE were approximately 5.3 and 1.9 times higher than those of the CS film, respectively. In addition, CF-4%SFE had strong DPPH radical scavenging activity (74.8 ± 2.3 %) and ABTS radical scavenging activity (84.06 ± 2.08 %). Fresh-cut bananas stored in CF-4%SFE showed less weight loss, starch loss, color and appearance change than those stored in traditional polyethylene film, which indicated that CF-4%SFE was much better at storing fresh-cut bananas than conventional plastic packaging. For these reasons, CF-SFE films have great potential as a candidate to replace traditional plastic packaging and extend the shelf life of packaged foods.
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Quitosana , Musa , Nanofibras , Quitosana/química , Quitina , Embalagem de Alimentos , Plásticos , FloresRESUMO
Purpose: Applying the parental mediation theory, this study investigates the main effects and interactive effects of three parental social media strategies, ie, active mediation, restrictive mediation, and non-intrusive inspection, on cyberbullying among teenagers. A matched child-parent survey was conducted with 642 secondary-school students aged 13-18 and their parents in China. Results: The results showed that active mediation was negatively associated with both cyberbullying victimization and perpetration. Restrictive mediation was not significantly associated with cyberbullying. Non-intrusive inspection was positively associated with cyberbullying perpetration but not associated with cyberbullying victimization. Moreover, the two-way interaction between active and restrictive mediation as well as the three-way interaction between the three parental mediation strategies significantly affected cyberbullying perpetration and victimization. Specifically, the combination of high-level active mediation and non-intrusive inspection with low-level restrictive mediation was the most effective strategy for preventing cyberbullying. Conclusion: This finding significantly contributes to the parental mediation literature and provide theoretical guidelines for parental intervention to prevent cyberbullying among teenager.
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The objective of this study was to make a film matrix containing chitosan (CS) and guar gum (GG), and to improve the physicochemical properties of the film using watermelon rind extract (WRE) as a cross-linker and active substance for the preservation of fresh-cut bananas. The results of Fourier transform infrared spectroscopy, X-ray diffraction and scanning electron microscopy showed that the WRE and CG matrix formed intermolecular hydrogen bond interactions, which made the structure of the resulting films more compact. With increasing amounts of WRE, the mechanical properties of the films were significantly increased, but the permeability of water vapor and oxygen was significantly decreased (p < 0.05). Notably, when the amount of extract reached 4 wt%, the DPPH radical scavenging activity of the composite film significantly increased to 83.24 %, and the antibacterial activity also reached its highest value. Fresh-cut bananas were stored at room temperature with polyethylene film, CG and CG-WRE. The CG with 4 wt% WRE effectively inhibited the changes in appearance, firmness, weight, color and total soluble solids content of fresh-cut bananas during storage. Therefore, CG-WRE as a novel active food packaging material, has good physicochemical properties and great potential to extend the shelf life of foods.
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Quitosana , Quitosana/química , Embalagem de Alimentos/métodos , Antibacterianos/farmacologia , Permeabilidade , Extratos Vegetais/farmacologia , Extratos Vegetais/químicaRESUMO
Our study analyzes the intention of Chinese health experts (health professionals and medical students) to correct health misinformation in social media. In an experimental 2 × 2 × 2 between-subjects factorial design (n = 415), we manipulated the experts' perception of the threat that health misinformation poses for online users, their self-efficacy with respect to correcting misinformation, and their self-affirmation. To select the potential influence factors, we draw on self-affirmation theory and the extended parallel process model. Results of our experiment revealed that correction intention increases if experts perceive the threat for online users as severe, believe that they are capable of countering the impact of misinformation, and have a high motivation to maintain a positive self-image of caring for others. We discuss the consequences of our findings for motivating experts to help reduce the adverse effects of health misinformation in social media.
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Intenção , Mídias Sociais , Humanos , Comunicação , Motivação , EstudantesRESUMO
Physician-patient conflicts are detrimental to doctor-patient relationship and sustainable healthcare delivery. In China, the status quo of the doctor-patient relationship is in great tension. Based on the uncertainty reduction theory (URT), the present study examined the relationship between patient-centered communication (PCC) and medical conflict, as well as the roles of perceived patients' trust, doctors' empathy, and expertise from physicians' perspectives. In March 2020, 509 physicians in China were recruited to participate in an online survey. The results revealed that PCC was negatively associated with physician-patient conflicts and that patient trust mediated the relationship. Additionally, doctors' empathy moderated PCC on patient trust, while expertise positively predicted physician-patient conflicts. Theoretical and practical implications for improving doctor-patient relationships were discussed.
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Relações Médico-Paciente , Médicos , Comunicação , Humanos , Assistência Centrada no Paciente , ConfiançaRESUMO
Silicone-rubber baby teats used to bottle-feed infants are frequently disinfected by moist heating. However, infant exposure to small microplastics (<10 µm) potentially released from the heated teats by hydrothermal decomposition has not been studied, owing to the limitations of conventional spectroscopy in visualizing microplastic formation and in characterizing the particles at the submicrometre scale. Here both the surfaces of silicone teats subjected to steam disinfection and the wash waters of the steamed teats were analysed using optical-photothermal infrared microspectroscopy. This new technique revealed submicrometre-resolved steam etching on and chemical modification of the teat surface. Numerous flake- or oil-film-shaped micro(nano)plastics (MNPs) (in the size range of 0.6-332 µm) presented in the wash waters, including cyclic and branched polysiloxanes or polyimides, which were generated by the steam-induced degradation of the base polydimethylsiloxane elastomer and the polyamide resin additive. The results indicated that by the age of one year, a baby could ingest >0.66 million elastomer-derived micro-sized plastics (MPs) (roughly 81% in 1.5-10 µm). Global MP emission from teat disinfection may be as high as 5.2 × 1013 particles per year. Our findings highlight an entry route for surface-active silicone-rubber-derived MNPs into both the human body and the environment. The health and environmental risks of the particles are as yet unknown.
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Desinfecção , Microplásticos , Imagem Óptica , Elastômeros de Silicone/química , Espectrofotometria Infravermelho , Vapor , Temperatura , Dimetilpolisiloxanos/química , Humanos , Imidas/química , Lactente , Resinas Sintéticas/químicaRESUMO
To better understand the effect of temperature on the growth and nitrate reductase activity (NRA) of Ulva prolifera and their relationships, the effects of five different temperatures (10, 15, 20, 25, and 30°C) were investigated in a laboratory setup. In this study, an optimization in vitro analysis method for Ulva prolifera NRA was developed. Under different treatments, the NRA, nitrate concentration, pH, the intracellular nitrate and nitrite concentrations, and the POC/PON were evaluated. The results of the in vitro analysis method showed it was optimal for the NRA assay when the extraction time was 6 min, enzymatic reaction time 30 min, volume of phenazine methosulfate (PMS) solution 50 µL, NADH concentration 0.36 mM, and KNO3 concentration 10 mM. The maximal NRA (NRAmax ) appeared on the 2nd day in the 10, 15, and 20°C (low-temperature) groups and on the 1st day in the 25 and 30°C (high-temperature) groups. The algal growth ended earlier at a high temperature, ending after 5 d at 30 and 25°C and 7 d at 20°C and 9 d at 15°C, and the alga at 10°C had been growing during the incubation period. Ulva prolifera cultivated in a range of 10-20°C had a long growth cycle and the NRA decreased with increasing temperature when exceeded 15°C, a positive correlation between algal growth and NRA was observed. This study supports NRA is a suitable proxy of the effects of temperature changes on the ability of Ulva prolifera to uptake and metabolize nitrogen nutrients.
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Ulva , Temperatura Baixa , Nitrato Redutases , Nitratos , TemperaturaRESUMO
OBJECTIVE: PEGylated superparamagnetic iron oxide (SPIO) is the most promising alternatives to gadolinium-based contrast agents (GBCAs) in MRI. This paper is to explore the imaging effects of PEGylated SPIO, which is influenced by particle sizes and surface polyethylene glycol (PEG) coating, using as MRI contrast agents at different magnetic field intensities. METHODS: Firstly, nine PEGylated monocrystalline SPIO nanoparticles with different nanocrystal sizes and different molecular weights PEG coating were prepared, and then physical and biological properties were analyzed. Finally, MRI imaging in vivo was performed to observe the imaging performance. RESULTS: Nine PEGylated monocrystalline SPIO nanoparticles have good relaxivities, serum stability, and biosecurity. At the same time, they show different imaging characteristics at different magnetic field intensities. Eight-nanometer SPIO@PEG5k is an effective T 2 contrast agent at 3.0 T (r 2/r 1 = 14.0), is an ideal T 1-T 2 dual-mode contrast agent at 1.5 T (r 2/r 1 = 6.52), and is also an effective T 1 contrast agent at 0.5 T (r 2/r 1 = 2.49), while 4-nm SPIO@PEG5k is a T 1-T 2 dual-mode contrast agent at 3.0 T (r 2/r 1 = 5.24), and is a useful T 1 contrast agent at 0.5 T (r 2/r 1 = 1.74) and 1.5 T (r 2/r 1 = 2.85). MRI studies in vivo at 3.0 T further confirm that 4-nm SPIO@PEG5k displays excellent T 1-T 2 dual-mode contrast enhancement, whereas 8-nm SPIO@PEG5k only displays T 2 contrast enhancement. CONCLUSION: PEGylated SPIOs with different nanocrystal sizes and PEG coating can be used as T 1, T 2, or T 1-T 2 dual-mode contrast agents to meet the clinical demands of MRI at specific magnetic fields.
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Meios de Contraste/química , Nanopartículas Magnéticas de Óxido de Ferro/química , Imageamento por Ressonância Magnética , Nanocompostos/química , Polietilenoglicóis/química , Animais , Campos Magnéticos , Nanopartículas Magnéticas de Óxido de Ferro/ultraestrutura , Masculino , Camundongos , Nanocompostos/ultraestrutura , Nanopartículas/química , Nanopartículas/ultraestrutura , Tamanho da Partícula , Células RAW 264.7 , Ratos Sprague-Dawley , Soro/metabolismoRESUMO
Background: In recent years, influenza has become a severe disease and pandemic threat. There are more than 290,000 to 650,000 influenza-related deaths globally each year. Influenza vaccination is the best way to prevent influenza and potentially serious influenza-related complications. The current study aims to examine the effectiveness of fear-induced health campaigns on social media in promoting influenza vaccination with the focus on different sources. Methods: A 2 × 3 × 2 (visible source × receiver source × technological source) factorial online experiment was designed to investigate the effectiveness of fear appeal messages offered by different sources on social media. A total of 534 college students were recruited to participate in the experiment. Results: Individuals who receive messages from a verified visible source have greater intention to perform flu vaccination and seek flu-related information than those who acquire messages from an unverified one. Besides, visible source, receiver source, and technological source interact to affect flu-related information seeking. Conclusions: In addition to the message itself, different levels of message sources on social media should be considered for e-health campaign design, especially visible sources.
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Influenza Humana , Medo , Promoção da Saúde , Humanos , Influenza Humana/prevenção & controle , Intenção , VacinaçãoRESUMO
In this communication, a paramagnetic bifunctional manganese(ii) chelate ([Mn(Dopa-EDTA)]2-) containing a catechol group is designed and synthesized. The catechol can bind iron ions on the surface of superparamagnetic iron oxide (SPIO) nanocrystals to form core-shell nanoparticles. Both 4 and 7 nm SPIO@[Mn(Dopa-EDTA)]2- show good water solubility, single-crystal dispersion, and low cytotoxicity. The study of the interplay between the longitudinal and transverse relaxation revealed that 4 nm SPIO@[Mn(Dopa-EDTA)]2- with lower r 2/r 1 = 1.75 at 0.5 T tends to be a perfect T 1 contrast agent while 7 nm SPIO@[Mn(Dopa-EDTA)]2- with a higher r 2/r 1 = 15.0 at 3.0 T tends to be a T 2 contrast agent. Interestingly, 4 nm SPIO@[Mn(Dopa-EDTA)]2- with an intermediate value of r 2/r 1 = 5.26 at 3.0 T could act as T 1-T 2 dual-modal contrast agent. In vivo imaging with the 4 nm SPIO@[Mn(Dopa-EDTA)]2- nanoparticle shows unique imaging features: (1) long-acting vascular imaging and different signal intensity changes between the liver parenchyma and blood vessels with the CEMRA sequence; (2) the synergistic contrast enhancement of hepatic imaging with the T 1WI and T 2WI sequence. In summary, these Fe/Mn hybrid core-shell nanoparticles, with their ease of synthesis, good biocompatibility, and synergistic contrast enhancement ability, may provide a useful method for tissue and vascular MR imaging.
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As a rising star of carbon allotropes, graphynes (GYs) merely consist of sp- and sp2-hybridized carbon atoms, which endow them a large conjugated network and expanded 2D porous structure. With unique topological structure, GYs display unusual semiconducting properties, especially in the aspects of charge mobility and electron transport. Among the members of the GY family, only graphdiyne (GD) can be successfully synthesized in large quantities. The advanced properties of GD make it promising in various applications. Here, the recent progress in the synthesis of GD and GD-based composites is reviewed as well as their applications in photorelated and electrocatalytic applications. It is hoped that this Review will promote the development and applications of carbon chemistry.
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Carbon-based nanocomposites have shown promising results in replacing commercial Pt/C as high-performance, low cost, nonprecious metal-based oxygen reduction reaction (ORR) catalysts. Developing unique nanostructures of active components (e.g., metal oxides) and carbon materials is essential for their application in next generation electrode materials for fuel cells and metal-air batteries. Herein, a general approach for the production of 1D porous nitrogen-doped graphitic carbon fibers embedded with active ORR components, (M/MOx , i.e., metal or metal oxide nanoparticles) using a facile two-step electrospinning and annealing process is reported. Metal nanoparticles/nanoclusters nucleate within the polymer nanofibers and subsequently catalyze graphitization of the surrounding polymer matrix and following oxidation, create an interconnected graphite-metal oxide framework with large pore channels, considerable active sites, and high specific surface area. The metal/metal oxide@N-doped graphitic carbon fibers, especially Co3 O4 , exhibit comparable ORR catalytic activity but superior stability and methanol tolerance versus Pt in alkaline solutions, which can be ascribed to the synergistic chemical coupling effects between Co3 O4 and robust 1D porous structures composed of interconnected N-doped graphitic nanocarbon rings. This finding provides a novel insight into the design of functional electrocatalysts using electrospun carbon nanomaterials for their application in energy storage and conversion fields.
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We report the biological synthesis of titania that is integrated into the silica-based cell walls of a titanium-resistant diatom, Fistulifera solaris. Titania is deposited across the diatom cell walls by simply incubating F. solaris in a culture medium containing a high concentration (2 mM) of a water-soluble organo-titanium compound, titanium(IV) bis(ammonium lactato) dihydroxide (TiBALDH) that would otherwise inhibit the growth of other diatom species. Furthermore, we genetically engineered the interfaces of the diatom cell walls with a titanium-associated peptide, which subsequently increased the Ti/Si atomic ratio by more than 50% (i.e., from 6.2 ± 0.2% to 9.7 ± 0.5%, as identified by inductively coupled plasma-atomic emission spectrometry). The titanium content on the F. solaris silica cell walls is one of the highest reported to date, and comparable to that of chemically synthesized TiO2-silica composites. Subsequent thermal annealing at 500 °C in air converted the cell wall-bound titania to nanocrystalline anatase TiO2, a highly photocatalytically active phase. We propose that incubation of the titanium-resistant F. solaris with TiBALDH as demonstrated in this study could be a promising bioprocess toward the scalable synthesis of TiO2. In addition, the genetic engineering we used to modulate the surface properties of diatom silica cell walls could be extended to synthesize controlled nanomaterials for multiple applications including bioremediation, water purification, and energy conversion/storage.
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The multishelled (Co2/3 Mn1/3 )(Co5/6 Mn1/6 )2O4 hollow microspheres with controllable shell numbers up to septuple shells are synthesized using developed sequential templating method. Exhilaratingly, the septuple-shelled complex metal oxide hollow microsphere is synthesized for the first time by doping Mn into Co3 O4 , leading to the change of crystalline rate of precursor. Used as electrode materials for alkaline rechargeable battery, it shows a remarkable reversible capacity (236.39 mAh g-1 at a current density of 1 A g-1 by three-electrode system and 106.85 mAh g-1 at 0.5 A g-1 in alkaline battery) and excellent cycling performance due to its unique structure.